UPDATE: Update release to 0.6.0 (#463)

Should we have a single version number at the root?

Cargo.lock

@@ -414,7 +414,7 @@ dependencies = [
 
 [[package]]
 name = "ironcalc"
-version = "0.5.0"
+version = "0.6.0"
 dependencies = [
  "bitcode",
  "chrono",
@@ -430,7 +430,7 @@ dependencies = [
 
 [[package]]
 name = "ironcalc_base"
-version = "0.5.0"
+version = "0.6.0"
 dependencies = [
  "bitcode",
  "chrono",
@@ -447,7 +447,7 @@ dependencies = [
 
 [[package]]
 name = "ironcalc_nodejs"
-version = "0.5.0"
+version = "0.6.0"
 dependencies = [
  "ironcalc",
  "napi",
@@ -782,7 +782,7 @@ dependencies = [
 
 [[package]]
 name = "pyroncalc"
-version = "0.5.7"
+version = "0.6.0"
 dependencies = [
  "bitcode",
  "ironcalc",
@@ -1075,7 +1075,7 @@ checksum = "9c8d87e72b64a3b4db28d11ce29237c246188f4f51057d65a7eab63b7987e423"
 
 [[package]]
 name = "wasm"
-version = "0.5.0"
+version = "0.6.0"
 dependencies = [
  "ironcalc_base",
  "serde",

Dockerfile

@@ -0,0 +1,93 @@
+FROM rust:latest AS builder
+
+WORKDIR /app
+COPY . .
+
+# Tools + wasm toolchain + Node via nvm
+RUN apt-get update && apt-get install -y --no-install-recommends \
+      bash curl ca-certificates make \
+    && rustup target add wasm32-unknown-unknown \
+    && cargo install wasm-pack \
+    && bash -lc "curl -fsSL https://raw.githubusercontent.com/nvm-sh/nvm/v0.40.3/install.sh | bash -" \
+    && bash -lc '\
+         export NVM_DIR="$HOME/.nvm" && \
+         source "$NVM_DIR/nvm.sh" && \
+         nvm install 22 && nvm alias default 22 && \
+         nroot="$NVM_DIR/versions/node/$(nvm version default)/bin" && \
+         ln -sf "$nroot/node" /usr/local/bin/node && \
+         ln -sf "$nroot/npm"  /usr/local/bin/npm  && \
+         ln -sf "$nroot/npx"  /usr/local/bin/npx \
+       ' \
+    && npm install typescript \
+    && rm -rf /var/lib/apt/lists/*
+
+# build the server
+RUN cargo build --release --manifest-path webapp/app.ironcalc.com/server/Cargo.toml
+
+# build the wasm
+RUN make -C bindings/wasm
+
+# build the widget
+WORKDIR /app/webapp/IronCalc
+RUN npm install && npm run build
+
+# build the frontend app
+WORKDIR /app/webapp/app.ironcalc.com/frontend
+RUN npm install && npm run build
+
+# build the xlsx_2_icalc binary (we don't need the release version here)
+WORKDIR /app/xlsx
+RUN cargo build
+
+WORKDIR /app
+# copy the artifacts to a dist/ directory
+RUN mkdir dist
+RUN mkdir dist/frontend
+RUN cp -r webapp/app.ironcalc.com/frontend/dist/* dist/frontend/
+RUN mkdir dist/server
+RUN cp webapp/app.ironcalc.com/server/target/release/ironcalc_server dist/server/
+RUN cp webapp/app.ironcalc.com/server/Rocket.toml dist/server/
+RUN cp webapp/app.ironcalc.com/server/ironcalc.sqlite dist/server/
+
+# Create ic files in docs
+RUN mkdir -p dist/frontend/models
+
+# Loop over all xlsx files in xlsx/tests/docs & templates and convert them to .ic
+RUN bash -lc 'set -euo pipefail; \
+  mkdir -p dist/frontend/models; \
+  shopt -s nullglob; \
+  for xlsx_file in xlsx/tests/docs/*.xlsx; do \
+    base_name="${xlsx_file##*/}"; base_name="${base_name%.xlsx}"; \
+    ./target/debug/xlsx_2_icalc "$xlsx_file" "dist/frontend/models/${base_name}.ic"; \
+  done; \
+  for xlsx_file in xlsx/tests/templates/*.xlsx; do \
+    base_name="${xlsx_file##*/}"; base_name="${base_name%.xlsx}"; \
+    ./target/debug/xlsx_2_icalc "$xlsx_file" "dist/frontend/models/${base_name}.ic"; \
+  done'
+
+# ---------- server runtime ----------
+FROM debian:bookworm-slim AS server-runtime
+RUN apt-get update && apt-get install -y --no-install-recommends ca-certificates && \
+    rm -rf /var/lib/apt/lists/*
+WORKDIR /app
+# Copy EVERYTHING you put in dist/server (binary + Rocket.toml + DB)
+COPY --from=builder /app/dist/server/ ./
+# Make sure Rocket binds to the container IP; explicitly point to the config file
+ENV ROCKET_ADDRESS=0.0.0.0 \
+    ROCKET_PORT=8000 \
+    ROCKET_CONFIG=/app/Rocket.toml
+EXPOSE 8000
+# Run from /app so relative paths in Rocket.toml/DB work
+CMD ["./ironcalc_server"]
+
+# ---------- caddy runtime (serves frontend + reverse-proxy /api) ----------
+FROM caddy:latest AS caddy-runtime
+
+WORKDIR /srv
+
+# Copy the frontend build output to /srv
+COPY --from=builder /app/dist/frontend/ /srv/
+
+# Copy the Caddyfile
+COPY --from=builder /app/webapp/app.ironcalc.com/Caddyfile.compose /etc/caddy/Caddyfile
+

README.md

@@ -31,7 +31,17 @@ This repository contains the main engine and the xlsx reader and writer.
 
 Programmed in Rust, you will be able to use it from a variety of programming languages like Python, JavaScript (wasm), nodejs and possibly R, Julia or Go.
 
-We will build different _skins_: in the terminal, as a desktop application or use it in you own web application.
+We will build different _skins_: in the terminal, as a desktop application or use it in your own web application.
+
+# Docker
+
+If you have docker installed just run:
+
+```bash
+docker compose up --build
+```
+
+head over to <http://localhost:2080> to test the application.
 
 # Building
 

base/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "ironcalc_base"
-version = "0.5.0"
+version = "0.6.0"
 authors = ["Nicolás Hatcher <nicolas@theuniverse.today>"]
 edition = "2021"
 homepage = "https://www.ironcalc.com"

base/src/expressions/parser/static_analysis.rs

@@ -341,7 +341,8 @@ fn static_analysis_offset(args: &[Node]) -> StaticResult {
         }
         _ => return StaticResult::Unknown,
     };
-    StaticResult::Unknown
+    // Both height and width are explicitly 1, so OFFSET will return a single cell
+    StaticResult::Scalar
 }
 
 // fn static_analysis_choose(_args: &[Node]) -> StaticResult {
@@ -575,6 +576,37 @@ fn args_signature_xnpv(arg_count: usize) -> Vec<Signature> {
     }
 }
 
+// NETWORKDAYS(start_date, end_date, [holidays])
+// Parameters: start_date (scalar), end_date (scalar), holidays (optional vector)
+fn args_signature_networkdays(arg_count: usize) -> Vec<Signature> {
+    if arg_count == 2 {
+        vec![Signature::Scalar, Signature::Scalar]
+    } else if arg_count == 3 {
+        vec![Signature::Scalar, Signature::Scalar, Signature::Vector]
+    } else {
+        vec![Signature::Error; arg_count]
+    }
+}
+
+// NETWORKDAYS.INTL(start_date, end_date, [weekend], [holidays])
+// Parameters: start_date (scalar), end_date (scalar), weekend (optional scalar), holidays (optional vector)
+fn args_signature_networkdays_intl(arg_count: usize) -> Vec<Signature> {
+    if arg_count == 2 {
+        vec![Signature::Scalar, Signature::Scalar]
+    } else if arg_count == 3 {
+        vec![Signature::Scalar, Signature::Scalar, Signature::Scalar]
+    } else if arg_count == 4 {
+        vec![
+            Signature::Scalar,
+            Signature::Scalar,
+            Signature::Scalar,
+            Signature::Vector,
+        ]
+    } else {
+        vec![Signature::Error; arg_count]
+    }
+}
+
 // FIXME: This is terrible duplications of efforts. We use the signature in at least three different places:
 // 1. When computing the function
 // 2. Checking the arguments to see if we need to insert the implicit intersection operator
@@ -690,13 +722,28 @@ fn get_function_args_signature(kind: &Function, arg_count: usize) -> Vec<Signatu
         Function::Maxifs => vec![Signature::Vector; arg_count],
         Function::Minifs => vec![Signature::Vector; arg_count],
         Function::Date => args_signature_scalars(arg_count, 3, 0),
+        Function::Datedif => args_signature_scalars(arg_count, 3, 0),
+        Function::Datevalue => args_signature_scalars(arg_count, 1, 0),
         Function::Day => args_signature_scalars(arg_count, 1, 0),
         Function::Edate => args_signature_scalars(arg_count, 2, 0),
         Function::Eomonth => args_signature_scalars(arg_count, 2, 0),
         Function::Month => args_signature_scalars(arg_count, 1, 0),
+        Function::Time => args_signature_scalars(arg_count, 3, 0),
+        Function::Timevalue => args_signature_scalars(arg_count, 1, 0),
+        Function::Hour => args_signature_scalars(arg_count, 1, 0),
+        Function::Minute => args_signature_scalars(arg_count, 1, 0),
+        Function::Second => args_signature_scalars(arg_count, 1, 0),
         Function::Now => args_signature_no_args(arg_count),
         Function::Today => args_signature_no_args(arg_count),
         Function::Year => args_signature_scalars(arg_count, 1, 0),
+        Function::Days => args_signature_scalars(arg_count, 2, 0),
+        Function::Days360 => args_signature_scalars(arg_count, 2, 1),
+        Function::Weekday => args_signature_scalars(arg_count, 1, 1),
+        Function::Weeknum => args_signature_scalars(arg_count, 1, 1),
+        Function::Workday => args_signature_scalars(arg_count, 2, 1),
+        Function::WorkdayIntl => args_signature_scalars(arg_count, 2, 2),
+        Function::Yearfrac => args_signature_scalars(arg_count, 2, 1),
+        Function::Isoweeknum => args_signature_scalars(arg_count, 1, 0),
         Function::Cumipmt => args_signature_scalars(arg_count, 6, 0),
         Function::Cumprinc => args_signature_scalars(arg_count, 6, 0),
         Function::Db => args_signature_scalars(arg_count, 4, 1),
@@ -785,6 +832,8 @@ fn get_function_args_signature(kind: &Function, arg_count: usize) -> Vec<Signatu
         Function::Formulatext => args_signature_scalars(arg_count, 1, 0),
         Function::Unicode => args_signature_scalars(arg_count, 1, 0),
         Function::Geomean => vec![Signature::Vector; arg_count],
+        Function::Networkdays => args_signature_networkdays(arg_count),
+        Function::NetworkdaysIntl => args_signature_networkdays_intl(arg_count),
     }
 }
 
@@ -896,12 +945,27 @@ fn static_analysis_on_function(kind: &Function, args: &[Node]) -> StaticResult {
         Function::Maxifs => not_implemented(args),
         Function::Minifs => not_implemented(args),
         Function::Date => not_implemented(args),
+        Function::Datedif => not_implemented(args),
+        Function::Datevalue => not_implemented(args),
         Function::Day => not_implemented(args),
         Function::Edate => not_implemented(args),
         Function::Month => not_implemented(args),
+        Function::Time => not_implemented(args),
+        Function::Timevalue => not_implemented(args),
+        Function::Hour => not_implemented(args),
+        Function::Minute => not_implemented(args),
+        Function::Second => not_implemented(args),
         Function::Now => not_implemented(args),
         Function::Today => not_implemented(args),
         Function::Year => not_implemented(args),
+        Function::Days => not_implemented(args),
+        Function::Days360 => not_implemented(args),
+        Function::Weekday => not_implemented(args),
+        Function::Weeknum => not_implemented(args),
+        Function::Workday => not_implemented(args),
+        Function::WorkdayIntl => not_implemented(args),
+        Function::Yearfrac => not_implemented(args),
+        Function::Isoweeknum => not_implemented(args),
         Function::Cumipmt => not_implemented(args),
         Function::Cumprinc => not_implemented(args),
         Function::Db => not_implemented(args),
@@ -990,5 +1054,7 @@ fn static_analysis_on_function(kind: &Function, args: &[Node]) -> StaticResult {
         Function::Eomonth => scalar_arguments(args),
         Function::Formulatext => not_implemented(args),
         Function::Geomean => not_implemented(args),
+        Function::Networkdays => not_implemented(args),
+        Function::NetworkdaysIntl => not_implemented(args),
     }
 }

base/src/formatter/dates.rs

@@ -8,6 +8,8 @@ use crate::constants::EXCEL_DATE_BASE;
 use crate::constants::MAXIMUM_DATE_SERIAL_NUMBER;
 use crate::constants::MINIMUM_DATE_SERIAL_NUMBER;
 
+pub const DATE_OUT_OF_RANGE_MESSAGE: &str = "Out of range parameters for date";
+
 #[inline]
 fn convert_to_serial_number(date: NaiveDate) -> i32 {
     date.num_days_from_ce() - EXCEL_DATE_BASE
@@ -37,7 +39,7 @@ pub fn from_excel_date(days: i64) -> Result<NaiveDate, String> {
 pub fn date_to_serial_number(day: u32, month: u32, year: i32) -> Result<i32, String> {
     match NaiveDate::from_ymd_opt(year, month, day) {
         Some(native_date) => Ok(convert_to_serial_number(native_date)),
-        None => Err("Out of range parameters for date".to_string()),
+        None => Err(DATE_OUT_OF_RANGE_MESSAGE.to_string()),
     }
 }
 
@@ -55,7 +57,7 @@ pub fn permissive_date_to_serial_number(day: i32, month: i32, year: i32) -> Resu
         return Ok(MINIMUM_DATE_SERIAL_NUMBER);
     }
     let Some(mut date) = NaiveDate::from_ymd_opt(year, 1, 1) else {
-        return Err("Out of range parameters for date".to_string());
+        return Err(DATE_OUT_OF_RANGE_MESSAGE.to_string());
     };
 
     // One thing to note for example is that even if you started with a year out of range
@@ -68,7 +70,7 @@ pub fn permissive_date_to_serial_number(day: i32, month: i32, year: i32) -> Resu
     // As a result, we have to run range checks as we parse the date from the biggest unit to the
     // smallest unit.
     if !is_date_within_range(date) {
-        return Err("Out of range parameters for date".to_string());
+        return Err(DATE_OUT_OF_RANGE_MESSAGE.to_string());
     }
 
     date = {
@@ -80,7 +82,7 @@ pub fn permissive_date_to_serial_number(day: i32, month: i32, year: i32) -> Resu
             date = date + Months::new(abs_month);
         }
         if !is_date_within_range(date) {
-            return Err("Out of range parameters for date".to_string());
+            return Err(DATE_OUT_OF_RANGE_MESSAGE.to_string());
         }
         date
     };
@@ -94,7 +96,7 @@ pub fn permissive_date_to_serial_number(day: i32, month: i32, year: i32) -> Resu
             date = date + Days::new(abs_day);
         }
         if !is_date_within_range(date) {
-            return Err("Out of range parameters for date".to_string());
+            return Err(DATE_OUT_OF_RANGE_MESSAGE.to_string());
         }
         date
     };

base/src/functions/mod.rs

@@ -148,13 +148,30 @@ pub enum Function {
 
     // Date and time
     Date,
+    Datedif,
+    Datevalue,
     Day,
     Edate,
     Eomonth,
     Month,
+    Time,
+    Timevalue,
+    Hour,
+    Minute,
+    Second,
     Now,
     Today,
     Year,
+    Networkdays,
+    NetworkdaysIntl,
+    Days,
+    Days360,
+    Weekday,
+    Weeknum,
+    Workday,
+    WorkdayIntl,
+    Yearfrac,
+    Isoweeknum,
 
     // Financial
     Cumipmt,
@@ -253,7 +270,7 @@ pub enum Function {
 }
 
 impl Function {
-    pub fn into_iter() -> IntoIter<Function, 198> {
+    pub fn into_iter() -> IntoIter<Function, 215> {
         [
             Function::And,
             Function::False,
@@ -362,9 +379,26 @@ impl Function {
             Function::Month,
             Function::Eomonth,
             Function::Date,
+            Function::Datedif,
+            Function::Datevalue,
             Function::Edate,
+            Function::Networkdays,
+            Function::NetworkdaysIntl,
+            Function::Time,
+            Function::Timevalue,
+            Function::Hour,
+            Function::Minute,
+            Function::Second,
             Function::Today,
             Function::Now,
+            Function::Days,
+            Function::Days360,
+            Function::Weekday,
+            Function::Weeknum,
+            Function::Workday,
+            Function::WorkdayIntl,
+            Function::Yearfrac,
+            Function::Isoweeknum,
             Function::Pmt,
             Function::Pv,
             Function::Rate,
@@ -494,6 +528,7 @@ impl Function {
             Function::Isformula => "_xlfn.ISFORMULA".to_string(),
             Function::Sheet => "_xlfn.SHEET".to_string(),
             Function::Formulatext => "_xlfn.FORMULATEXT".to_string(),
+            Function::Isoweeknum => "_xlfn.ISOWEEKNUM".to_string(),
             _ => self.to_string(),
         }
     }
@@ -631,9 +666,26 @@ impl Function {
             "EOMONTH" => Some(Function::Eomonth),
             "MONTH" => Some(Function::Month),
             "DATE" => Some(Function::Date),
+            "DATEDIF" => Some(Function::Datedif),
+            "DATEVALUE" => Some(Function::Datevalue),
             "EDATE" => Some(Function::Edate),
+            "NETWORKDAYS" => Some(Function::Networkdays),
+            "NETWORKDAYS.INTL" => Some(Function::NetworkdaysIntl),
+            "TIME" => Some(Function::Time),
+            "TIMEVALUE" => Some(Function::Timevalue),
+            "HOUR" => Some(Function::Hour),
+            "MINUTE" => Some(Function::Minute),
+            "SECOND" => Some(Function::Second),
             "TODAY" => Some(Function::Today),
             "NOW" => Some(Function::Now),
+            "DAYS" | "_XLFN.DAYS" => Some(Function::Days),
+            "DAYS360" => Some(Function::Days360),
+            "WEEKDAY" => Some(Function::Weekday),
+            "WEEKNUM" => Some(Function::Weeknum),
+            "WORKDAY" => Some(Function::Workday),
+            "WORKDAY.INTL" => Some(Function::WorkdayIntl),
+            "YEARFRAC" => Some(Function::Yearfrac),
+            "ISOWEEKNUM" | "_XLFN.ISOWEEKNUM" => Some(Function::Isoweeknum),
             // Financial
             "PMT" => Some(Function::Pmt),
             "PV" => Some(Function::Pv),
@@ -841,9 +893,26 @@ impl fmt::Display for Function {
             Function::Month => write!(f, "MONTH"),
             Function::Eomonth => write!(f, "EOMONTH"),
             Function::Date => write!(f, "DATE"),
+            Function::Datedif => write!(f, "DATEDIF"),
+            Function::Datevalue => write!(f, "DATEVALUE"),
             Function::Edate => write!(f, "EDATE"),
+            Function::Networkdays => write!(f, "NETWORKDAYS"),
+            Function::NetworkdaysIntl => write!(f, "NETWORKDAYS.INTL"),
+            Function::Time => write!(f, "TIME"),
+            Function::Timevalue => write!(f, "TIMEVALUE"),
+            Function::Hour => write!(f, "HOUR"),
+            Function::Minute => write!(f, "MINUTE"),
+            Function::Second => write!(f, "SECOND"),
             Function::Today => write!(f, "TODAY"),
             Function::Now => write!(f, "NOW"),
+            Function::Days => write!(f, "DAYS"),
+            Function::Days360 => write!(f, "DAYS360"),
+            Function::Weekday => write!(f, "WEEKDAY"),
+            Function::Weeknum => write!(f, "WEEKNUM"),
+            Function::Workday => write!(f, "WORKDAY"),
+            Function::WorkdayIntl => write!(f, "WORKDAY.INTL"),
+            Function::Yearfrac => write!(f, "YEARFRAC"),
+            Function::Isoweeknum => write!(f, "ISOWEEKNUM"),
             Function::Pmt => write!(f, "PMT"),
             Function::Pv => write!(f, "PV"),
             Function::Rate => write!(f, "RATE"),
@@ -1082,9 +1151,26 @@ impl Model {
             Function::Eomonth => self.fn_eomonth(args, cell),
             Function::Month => self.fn_month(args, cell),
             Function::Date => self.fn_date(args, cell),
+            Function::Datedif => self.fn_datedif(args, cell),
+            Function::Datevalue => self.fn_datevalue(args, cell),
             Function::Edate => self.fn_edate(args, cell),
+            Function::Networkdays => self.fn_networkdays(args, cell),
+            Function::NetworkdaysIntl => self.fn_networkdays_intl(args, cell),
+            Function::Time => self.fn_time(args, cell),
+            Function::Timevalue => self.fn_timevalue(args, cell),
+            Function::Hour => self.fn_hour(args, cell),
+            Function::Minute => self.fn_minute(args, cell),
+            Function::Second => self.fn_second(args, cell),
             Function::Today => self.fn_today(args, cell),
             Function::Now => self.fn_now(args, cell),
+            Function::Days => self.fn_days(args, cell),
+            Function::Days360 => self.fn_days360(args, cell),
+            Function::Weekday => self.fn_weekday(args, cell),
+            Function::Weeknum => self.fn_weeknum(args, cell),
+            Function::Workday => self.fn_workday(args, cell),
+            Function::WorkdayIntl => self.fn_workday_intl(args, cell),
+            Function::Yearfrac => self.fn_yearfrac(args, cell),
+            Function::Isoweeknum => self.fn_isoweeknum(args, cell),
             // Financial
             Function::Pmt => self.fn_pmt(args, cell),
             Function::Pv => self.fn_pv(args, cell),

base/src/test/mod.rs

@@ -7,6 +7,8 @@ mod test_column_width;
 mod test_criteria;
 mod test_currency;
 mod test_date_and_time;
+mod test_datedif_leap_month_end;
+mod test_days360_month_end;
 mod test_error_propagation;
 mod test_fn_average;
 mod test_fn_averageifs;
@@ -27,6 +29,7 @@ mod test_fn_sum;
 mod test_fn_sumifs;
 mod test_fn_textbefore;
 mod test_fn_textjoin;
+mod test_fn_time;
 mod test_fn_unicode;
 mod test_frozen_rows_columns;
 mod test_general;
@@ -43,8 +46,11 @@ mod test_sheets;
 mod test_styles;
 mod test_trigonometric;
 mod test_true_false;
+mod test_weekday_return_types;
+mod test_weeknum_return_types;
 mod test_workbook;
 mod test_worksheet;
+mod test_yearfrac_basis;
 pub(crate) mod util;
 
 mod engineering;
@@ -65,6 +71,7 @@ mod test_issue_155;
 mod test_ln;
 mod test_log;
 mod test_log10;
+mod test_networkdays;
 mod test_percentage;
 mod test_set_functions_error_handling;
 mod test_today;

base/src/test/test_date_and_time.rs

@@ -6,6 +6,11 @@
 /// We can also enter examples that illustrate/document a part of the function
 use crate::{cell::CellValue, test::util::new_empty_model};
 
+// Excel uses a serial date system where Jan 1, 1900 = 1 (though it treats 1900 as a leap year)
+// Most test dates are documented inline, but we define boundary values here:
+const EXCEL_MAX_DATE: f64 = 2958465.0; // Dec 31, 9999 - used in boundary tests
+const EXCEL_INVALID_DATE: f64 = 2958466.0; // One day past max - used in error tests
+
 #[test]
 fn test_fn_date_arguments() {
     let mut model = new_empty_model();
@@ -216,3 +221,382 @@ fn test_date_early_dates() {
         Ok(CellValue::Number(61.0))
     );
 }
+#[test]
+fn test_days_function() {
+    let mut model = new_empty_model();
+
+    // Basic functionality
+    model._set("A1", "=DAYS(44570,44561)");
+    model._set("A2", "=DAYS(44561,44570)"); // Reversed order
+    model._set("A3", "=DAYS(44561,44561)");
+
+    // Edge cases
+    model._set("A4", "=DAYS(1,2)"); // Early dates
+    model._set(
+        "A5",
+        &format!("=DAYS({},{})", EXCEL_MAX_DATE, EXCEL_MAX_DATE - 1.0),
+    ); // Near max date
+
+    // Error cases - wrong argument count
+    model._set("A6", "=DAYS()");
+    model._set("A7", "=DAYS(44561)");
+    model._set("A8", "=DAYS(44561,44570,1)");
+
+    // Error cases - invalid dates
+    model._set("A9", "=DAYS(-1,44561)");
+    model._set("A10", &format!("=DAYS(44561,{EXCEL_INVALID_DATE})"));
+
+    model.evaluate();
+
+    assert_eq!(model._get_text("A1"), *"9");
+    assert_eq!(model._get_text("A2"), *"-9");
+    assert_eq!(model._get_text("A3"), *"0");
+    assert_eq!(model._get_text("A4"), *"-1"); // DAYS(1,2) = 1-2 = -1
+    assert_eq!(model._get_text("A5"), *"1");
+    assert_eq!(model._get_text("A6"), *"#ERROR!");
+    assert_eq!(model._get_text("A7"), *"#ERROR!");
+    assert_eq!(model._get_text("A8"), *"#ERROR!");
+    assert_eq!(model._get_text("A9"), *"#NUM!");
+    assert_eq!(model._get_text("A10"), *"#NUM!");
+}
+
+#[test]
+fn test_days360_function() {
+    let mut model = new_empty_model();
+
+    // Basic functionality with different basis values
+    model._set("A1", "=DAYS360(44196,44560)"); // Default basis (US 30/360)
+    model._set("A2", "=DAYS360(44196,44560,FALSE)"); // US 30/360 explicitly
+    model._set("A3", "=DAYS360(44196,44560,TRUE)"); // European 30/360
+
+    // Same date
+    model._set("A4", "=DAYS360(44561,44561)");
+    model._set("A5", "=DAYS360(44561,44561,TRUE)");
+
+    // Reverse order (negative result)
+    model._set("A6", "=DAYS360(44560,44196)");
+    model._set("A7", "=DAYS360(44560,44196,TRUE)");
+
+    // Edge cases
+    model._set("A8", "=DAYS360(1,2)");
+    model._set("A9", "=DAYS360(1,2,FALSE)");
+
+    // Error cases - wrong argument count
+    model._set("A10", "=DAYS360()");
+    model._set("A11", "=DAYS360(44561)");
+    model._set("A12", "=DAYS360(44561,44570,TRUE,1)");
+
+    // Error cases - invalid dates
+    model._set("A13", "=DAYS360(-1,44561)");
+    model._set("A14", &format!("=DAYS360(44561,{EXCEL_INVALID_DATE})"));
+
+    model.evaluate();
+
+    assert_eq!(model._get_text("A1"), *"360");
+    assert_eq!(model._get_text("A2"), *"360");
+    assert_eq!(model._get_text("A3"), *"360");
+    assert_eq!(model._get_text("A4"), *"0");
+    assert_eq!(model._get_text("A5"), *"0");
+    assert_eq!(model._get_text("A6"), *"-360");
+    assert_eq!(model._get_text("A7"), *"-360");
+    assert_eq!(model._get_text("A8"), *"1");
+    assert_eq!(model._get_text("A9"), *"1");
+    assert_eq!(model._get_text("A10"), *"#ERROR!");
+    assert_eq!(model._get_text("A11"), *"#ERROR!");
+    assert_eq!(model._get_text("A12"), *"#ERROR!");
+    assert_eq!(model._get_text("A13"), *"#NUM!");
+    assert_eq!(model._get_text("A14"), *"#NUM!");
+}
+
+#[test]
+fn test_weekday_function() {
+    let mut model = new_empty_model();
+
+    // Test return_type parameter variations with one known date (Friday 44561)
+    model._set("A1", "=WEEKDAY(44561)"); // Default: Sun=1, Fri=6
+    model._set("A2", "=WEEKDAY(44561,2)"); // Mon=1, Fri=5
+    model._set("A3", "=WEEKDAY(44561,3)"); // Mon=0, Fri=4
+
+    // Test boundary days (Sun/Mon) to verify return_type logic
+    model._set("A4", "=WEEKDAY(44556,1)"); // Sunday: should be 1
+    model._set("A5", "=WEEKDAY(44556,2)"); // Sunday: should be 7
+    model._set("A6", "=WEEKDAY(44557,2)"); // Monday: should be 1
+
+    // Error cases
+    model._set("A7", "=WEEKDAY()"); // Wrong arg count
+    model._set("A8", "=WEEKDAY(44561,0)"); // Invalid return_type
+    model._set("A9", "=WEEKDAY(-1)"); // Invalid date
+
+    model.evaluate();
+
+    // Core functionality
+    assert_eq!(model._get_text("A1"), *"6"); // Friday default
+    assert_eq!(model._get_text("A2"), *"5"); // Friday Mon=1
+    assert_eq!(model._get_text("A3"), *"4"); // Friday Mon=0
+
+    // Boundary verification
+    assert_eq!(model._get_text("A4"), *"1"); // Sunday Sun=1
+    assert_eq!(model._get_text("A5"), *"7"); // Sunday Mon=1
+    assert_eq!(model._get_text("A6"), *"1"); // Monday Mon=1
+
+    // Error cases
+    assert_eq!(model._get_text("A7"), *"#ERROR!");
+    assert_eq!(model._get_text("A8"), *"#VALUE!");
+    assert_eq!(model._get_text("A9"), *"#NUM!");
+}
+
+#[test]
+fn test_weeknum_function() {
+    let mut model = new_empty_model();
+
+    // Test different return_type values (1=week starts Sunday, 2=week starts Monday)
+    model._set("A1", "=WEEKNUM(44561)"); // Default return_type=1
+    model._set("A2", "=WEEKNUM(44561,1)"); // Sunday start
+    model._set("A3", "=WEEKNUM(44561,2)"); // Monday start
+
+    // Test year boundaries
+    model._set("A4", "=WEEKNUM(43831,1)"); // Jan 1, 2020 (Wednesday)
+    model._set("A5", "=WEEKNUM(43831,2)"); // Jan 1, 2020 (Wednesday)
+    model._set("A6", "=WEEKNUM(44196,1)"); // Dec 31, 2020 (Thursday)
+    model._set("A7", "=WEEKNUM(44196,2)"); // Dec 31, 2020 (Thursday)
+
+    // Test first and last weeks of year
+    model._set("A8", "=WEEKNUM(44197,1)"); // Jan 1, 2021 (Friday)
+    model._set("A9", "=WEEKNUM(44197,2)"); // Jan 1, 2021 (Friday)
+    model._set("A10", "=WEEKNUM(44561,1)"); // Dec 31, 2021 (Friday)
+    model._set("A11", "=WEEKNUM(44561,2)"); // Dec 31, 2021 (Friday)
+
+    // Error cases - wrong argument count
+    model._set("A12", "=WEEKNUM()");
+    model._set("A13", "=WEEKNUM(44561,1,1)");
+
+    // Error cases - invalid return_type
+    model._set("A14", "=WEEKNUM(44561,0)");
+    model._set("A15", "=WEEKNUM(44561,3)");
+    model._set("A16", "=WEEKNUM(44561,-1)");
+
+    // Error cases - invalid dates
+    model._set("A17", "=WEEKNUM(-1)");
+    model._set("A18", &format!("=WEEKNUM({EXCEL_INVALID_DATE})"));
+
+    model.evaluate();
+
+    // Basic functionality
+    assert_eq!(model._get_text("A1"), *"53"); // Week 53
+    assert_eq!(model._get_text("A2"), *"53"); // Week 53 (Sunday start)
+    assert_eq!(model._get_text("A3"), *"53"); // Week 53 (Monday start)
+
+    // Year boundary tests
+    assert_eq!(model._get_text("A4"), *"1"); // Jan 1, 2020 (Sunday start)
+    assert_eq!(model._get_text("A5"), *"1"); // Jan 1, 2020 (Monday start)
+    assert_eq!(model._get_text("A6"), *"53"); // Dec 31, 2020 (Sunday start)
+    assert_eq!(model._get_text("A7"), *"53"); // Dec 31, 2020 (Monday start)
+
+    // 2021 tests
+    assert_eq!(model._get_text("A8"), *"1"); // Jan 1, 2021 (Sunday start)
+    assert_eq!(model._get_text("A9"), *"1"); // Jan 1, 2021 (Monday start)
+    assert_eq!(model._get_text("A10"), *"53"); // Dec 31, 2021 (Sunday start)
+    assert_eq!(model._get_text("A11"), *"53"); // Dec 31, 2021 (Monday start)
+
+    // Error cases
+    assert_eq!(model._get_text("A12"), *"#ERROR!");
+    assert_eq!(model._get_text("A13"), *"#ERROR!");
+    assert_eq!(model._get_text("A14"), *"#VALUE!");
+    assert_eq!(model._get_text("A15"), *"#VALUE!");
+    assert_eq!(model._get_text("A16"), *"#VALUE!");
+    assert_eq!(model._get_text("A17"), *"#NUM!");
+    assert_eq!(model._get_text("A18"), *"#NUM!");
+}
+
+#[test]
+fn test_workday_function() {
+    let mut model = new_empty_model();
+
+    // Basic functionality
+    model._set("A1", "=WORKDAY(44560,1)");
+    model._set("A2", "=WORKDAY(44561,-1)");
+    model._set("A3", "=WORKDAY(44561,0)");
+    model._set("A4", "=WORKDAY(44560,5)");
+
+    // Test with holidays
+    model._set("B1", "44561");
+    model._set("A5", "=WORKDAY(44560,1,B1)"); // Should skip the holiday
+    model._set("B2", "44562");
+    model._set("B3", "44563");
+    model._set("A6", "=WORKDAY(44560,3,B1:B3)"); // Multiple holidays
+
+    // Test starting on weekend
+    model._set("A7", "=WORKDAY(44562,1)"); // Saturday start
+    model._set("A8", "=WORKDAY(44563,1)"); // Sunday start
+
+    // Test negative workdays
+    model._set("A9", "=WORKDAY(44565,-3)"); // Go backwards 3 days
+    model._set("A10", "=WORKDAY(44565,-5,B1:B3)"); // Backwards with holidays
+
+    // Edge cases
+    model._set("A11", "=WORKDAY(1,1)"); // Early date
+    model._set("A12", "=WORKDAY(100000,10)"); // Large numbers
+
+    // Error cases - wrong argument count
+    model._set("A13", "=WORKDAY()");
+    model._set("A14", "=WORKDAY(44560)");
+    model._set("A15", "=WORKDAY(44560,1,B1,B2)");
+
+    // Error cases - invalid dates
+    model._set("A16", "=WORKDAY(-1,1)");
+    model._set("A17", &format!("=WORKDAY({EXCEL_INVALID_DATE},1)"));
+
+    // Error cases - invalid holiday dates
+    model._set("B4", "-1");
+    model._set("A18", "=WORKDAY(44560,1,B4)");
+
+    model.evaluate();
+
+    // Basic functionality
+    assert_eq!(model._get_text("A1"), *"44561"); // 1 day forward
+    assert_eq!(model._get_text("A2"), *"44560"); // 1 day backward
+    assert_eq!(model._get_text("A3"), *"44561"); // 0 days
+    assert_eq!(model._get_text("A4"), *"44567"); // 5 days forward
+
+    // With holidays
+    assert_eq!(model._get_text("A5"), *"44564"); // Skip holiday, go to Monday
+    assert_eq!(model._get_text("A6"), *"44566"); // Skip multiple holidays
+
+    // Weekend starts
+    assert_eq!(model._get_text("A7"), *"44564"); // From Saturday
+    assert_eq!(model._get_text("A8"), *"44564"); // From Sunday
+
+    // Negative workdays
+    assert_eq!(model._get_text("A9"), *"44560"); // 3 days back
+    assert_eq!(model._get_text("A10"), *"44557"); // 5 days back with holidays
+
+    // Edge cases
+    assert_eq!(model._get_text("A11"), *"2"); // Early date
+    assert_eq!(model._get_text("A12"), *"100014"); // Large numbers
+
+    // Error cases
+    assert_eq!(model._get_text("A13"), *"#ERROR!");
+    assert_eq!(model._get_text("A14"), *"#ERROR!");
+    assert_eq!(model._get_text("A15"), *"#ERROR!");
+    assert_eq!(model._get_text("A16"), *"#NUM!");
+    assert_eq!(model._get_text("A17"), *"#NUM!");
+    assert_eq!(model._get_text("A18"), *"#NUM!"); // Invalid holiday
+}
+
+#[test]
+fn test_workday_intl_function() {
+    let mut model = new_empty_model();
+
+    // Test key weekend mask types
+    model._set("A1", "=WORKDAY.INTL(44560,1,1)"); // Numeric: standard (Sat-Sun)
+    model._set("A2", "=WORKDAY.INTL(44560,1,2)"); // Numeric: Sun-Mon
+    model._set("A3", "=WORKDAY.INTL(44560,1,\"0000001\")"); // String: Sunday only
+    model._set("A4", "=WORKDAY.INTL(44560,1,\"1100000\")"); // String: Mon-Tue
+
+    // Test with holidays
+    model._set("B1", "44561");
+    model._set("A5", "=WORKDAY.INTL(44560,2,1,B1)"); // Standard + holiday
+    model._set("A6", "=WORKDAY.INTL(44560,2,7,B1)"); // Fri-Sat + holiday
+
+    // Basic edge cases
+    model._set("A7", "=WORKDAY.INTL(44561,0,1)"); // Zero days
+    model._set("A8", "=WORKDAY.INTL(44565,-1,1)"); // Negative days
+
+    // Error cases
+    model._set("A9", "=WORKDAY.INTL()"); // Wrong arg count
+    model._set("A10", "=WORKDAY.INTL(44560,1,0)"); // Invalid weekend mask
+    model._set("A11", "=WORKDAY.INTL(44560,1,\"123\")"); // Invalid string mask
+    model._set("A12", "=WORKDAY.INTL(-1,1,1)"); // Invalid date
+
+    model.evaluate();
+
+    // Weekend mask functionality
+    assert_eq!(model._get_text("A1"), *"44561"); // Standard weekend
+    assert_eq!(model._get_text("A2"), *"44561"); // Sun-Mon weekend
+    assert_eq!(model._get_text("A3"), *"44561"); // Sunday only
+    assert_eq!(model._get_text("A4"), *"44561"); // Mon-Tue weekend
+
+    // With holidays
+    assert_eq!(model._get_text("A5"), *"44565"); // Skip holiday + standard weekend
+    assert_eq!(model._get_text("A6"), *"44564"); // Skip holiday + Fri-Sat weekend
+
+    // Edge cases
+    assert_eq!(model._get_text("A7"), *"44561"); // Zero days
+    assert_eq!(model._get_text("A8"), *"44564"); // Negative days
+
+    // Error cases
+    assert_eq!(model._get_text("A9"), *"#ERROR!");
+    assert_eq!(model._get_text("A10"), *"#NUM!");
+    assert_eq!(model._get_text("A11"), *"#VALUE!");
+    assert_eq!(model._get_text("A12"), *"#NUM!");
+}
+
+#[test]
+fn test_yearfrac_function() {
+    let mut model = new_empty_model();
+
+    // Test key basis values (not exhaustive - just verify parameter works)
+    model._set("A1", "=YEARFRAC(44561,44926)"); // Default (30/360)
+    model._set("A2", "=YEARFRAC(44561,44926,1)"); // Actual/actual
+    model._set("A3", "=YEARFRAC(44561,44926,4)"); // European 30/360
+
+    // Edge cases
+    model._set("A4", "=YEARFRAC(44561,44561,1)"); // Same date = 0
+    model._set("A5", "=YEARFRAC(44926,44561,1)"); // Reverse = negative
+    model._set("A6", "=YEARFRAC(44197,44562,1)"); // Exact year (2021)
+
+    // Error cases
+    model._set("A7", "=YEARFRAC()"); // Wrong arg count
+    model._set("A8", "=YEARFRAC(44561,44926,5)"); // Invalid basis
+    model._set("A9", "=YEARFRAC(-1,44926,1)"); // Invalid date
+
+    model.evaluate();
+
+    // Basic functionality (approximate values expected)
+    assert_eq!(model._get_text("A1"), *"1"); // About 1 year
+    assert_eq!(model._get_text("A2"), *"1"); // About 1 year
+    assert_eq!(model._get_text("A3"), *"1"); // About 1 year
+
+    // Edge cases
+    assert_eq!(model._get_text("A4"), *"0"); // Same date
+    assert_eq!(model._get_text("A5"), *"-1"); // Negative
+    assert_eq!(model._get_text("A6"), *"1"); // Exact year
+
+    // Error cases
+    assert_eq!(model._get_text("A7"), *"#ERROR!");
+    assert_eq!(model._get_text("A8"), *"#NUM!"); // Invalid basis should return #NUM!
+    assert_eq!(model._get_text("A9"), *"#NUM!");
+}
+
+#[test]
+fn test_isoweeknum_function() {
+    let mut model = new_empty_model();
+
+    // Basic functionality
+    model._set("A1", "=ISOWEEKNUM(44563)"); // Mid-week date
+    model._set("A2", "=ISOWEEKNUM(44561)"); // Year-end date
+
+    // Key ISO week boundaries (just critical cases)
+    model._set("A3", "=ISOWEEKNUM(44197)"); // Jan 1, 2021 (Fri) -> Week 53 of 2020
+    model._set("A4", "=ISOWEEKNUM(44200)"); // Jan 4, 2021 (Mon) -> Week 1 of 2021
+    model._set("A5", "=ISOWEEKNUM(44564)"); // Jan 3, 2022 (Mon) -> Week 1 of 2022
+
+    // Error cases
+    model._set("A6", "=ISOWEEKNUM()"); // Wrong arg count
+    model._set("A7", "=ISOWEEKNUM(-1)"); // Invalid date
+
+    model.evaluate();
+
+    // Basic functionality
+    assert_eq!(model._get_text("A1"), *"52");
+    assert_eq!(model._get_text("A2"), *"52");
+
+    // ISO week boundaries
+    assert_eq!(model._get_text("A3"), *"53"); // Week 53 of previous year
+    assert_eq!(model._get_text("A4"), *"1"); // Week 1 of current year
+    assert_eq!(model._get_text("A5"), *"1"); // Week 1 of next year
+
+    // Error cases
+    assert_eq!(model._get_text("A6"), *"#ERROR!");
+    assert_eq!(model._get_text("A7"), *"#NUM!");
+}

base/src/test/test_datedif_leap_month_end.rs

@@ -0,0 +1,33 @@
+use crate::test::util::new_empty_model;
+
+#[test]
+fn test_datedif_yd_leap_year_edge_cases() {
+    let mut model = new_empty_model();
+
+    // 29 Feb 2020 → 28 Feb 2021   (should be 0 days)
+    model._set("A1", "=DATEDIF(\"29/2/2020\", \"28/2/2021\", \"YD\")");
+
+    // 29 Feb 2020 → 1 Mar 2021    (should be 1 day)
+    model._set("A2", "=DATEDIF(\"29/2/2020\", \"2021-03-01\", \"YD\")");
+
+    model.evaluate();
+
+    assert_eq!(model._get_text("A1"), *"0");
+    assert_eq!(model._get_text("A2"), *"1");
+}
+
+#[test]
+fn test_datedif_md_month_end_edge_cases() {
+    let mut model = new_empty_model();
+
+    // 31 Jan 2021 → 28 Feb 2021 (non-leap) => 28
+    model._set("B1", "=DATEDIF(\"31/1/2021\", \"28/2/2021\", \"MD\")");
+
+    // 31 Jan 2020 → 29 Feb 2020 (leap) => 29
+    model._set("B2", "=DATEDIF(\"31/1/2020\", \"29/2/2020\", \"MD\")");
+
+    model.evaluate();
+
+    assert_eq!(model._get_text("B1"), *"28");
+    assert_eq!(model._get_text("B2"), *"29");
+}

base/src/test/test_days360_month_end.rs

@@ -0,0 +1,43 @@
+use crate::test::util::new_empty_model;
+
+#[test]
+fn test_days360_month_end_us() {
+    let mut model = new_empty_model();
+
+    // 31 Jan 2021 -> 28 Feb 2021 (non-leap)
+    model._set("A1", "=DAYS360(DATE(2021,1,31),DATE(2021,2,28))");
+
+    // 31 Jan 2020 -> 28 Feb 2020 (leap year – not last day of Feb)
+    model._set("A2", "=DAYS360(DATE(2020,1,31),DATE(2020,2,28))");
+
+    // 28 Feb 2020 -> 31 Mar 2020 (leap year span crossing month ends)
+    model._set("A3", "=DAYS360(DATE(2020,2,28),DATE(2020,3,31))");
+
+    // 30 Apr 2021 -> 31 May 2021 (end-of-month adjustment rule)
+    model._set("A4", "=DAYS360(DATE(2021,4,30),DATE(2021,5,31))");
+
+    model.evaluate();
+
+    assert_eq!(model._get_text("A1"), *"30");
+    assert_eq!(model._get_text("A2"), *"28");
+    assert_eq!(model._get_text("A3"), *"33");
+    assert_eq!(model._get_text("A4"), *"30");
+}
+
+#[test]
+fn test_days360_month_end_european() {
+    let mut model = new_empty_model();
+
+    // European basis = TRUE (or 1)
+    model._set("B1", "=DAYS360(DATE(2021,1,31),DATE(2021,2,28),TRUE)");
+
+    model._set("B2", "=DAYS360(DATE(2020,1,31),DATE(2020,2,29),TRUE)");
+
+    model._set("B3", "=DAYS360(DATE(2021,8,31),DATE(2021,9,30),TRUE)");
+
+    model.evaluate();
+
+    assert_eq!(model._get_text("B1"), *"28");
+    assert_eq!(model._get_text("B2"), *"29");
+    assert_eq!(model._get_text("B3"), *"30");
+}

base/src/test/test_fn_datevalue_datedif.rs

@@ -0,0 +1,182 @@
+#![allow(clippy::unwrap_used)]
+
+use crate::test::util::new_empty_model;
+use crate::types::Cell;
+
+// Helper to evaluate a formula and return the formatted text
+fn eval_formula(formula: &str) -> String {
+    let mut model = new_empty_model();
+    model._set("A1", formula);
+    model.evaluate();
+    model._get_text("A1")
+}
+
+// Helper that evaluates a formula and returns the raw value of A1 as a Result<f64, String>
+fn eval_formula_raw_number(formula: &str) -> Result<f64, String> {
+    let mut model = new_empty_model();
+    model._set("A1", formula);
+    model.evaluate();
+    match model._get_cell("A1") {
+        Cell::NumberCell { v, .. } => Ok(*v),
+        Cell::BooleanCell { v, .. } => Ok(if *v { 1.0 } else { 0.0 }),
+        Cell::ErrorCell { ei, .. } => Err(format!("{}", ei)),
+        _ => Err(model._get_text("A1")),
+    }
+}
+
+#[test]
+fn test_datevalue_basic_numeric() {
+    // DATEVALUE should return the serial number representing the date, **not** a formatted date
+    assert_eq!(
+        eval_formula_raw_number("=DATEVALUE(\"2/1/2023\")").unwrap(),
+        44958.0
+    );
+}
+
+#[test]
+fn test_datevalue_mmdd_with_leading_zero() {
+    assert_eq!(
+        eval_formula_raw_number("=DATEVALUE(\"02/01/2023\")").unwrap(),
+        44958.0
+    ); // 1-Feb-2023
+}
+
+#[test]
+fn test_datevalue_iso() {
+    assert_eq!(
+        eval_formula_raw_number("=DATEVALUE(\"2023-01-02\")").unwrap(),
+        44928.0
+    );
+}
+
+#[test]
+fn test_datevalue_month_name() {
+    assert_eq!(
+        eval_formula_raw_number("=DATEVALUE(\"2-Jan-23\")").unwrap(),
+        44928.0
+    );
+}
+
+#[test]
+fn test_datevalue_ambiguous_ddmm() {
+    // 01/02/2023 interpreted as MM/DD -> 2-Jan-2023
+    assert_eq!(
+        eval_formula_raw_number("=DATEVALUE(\"01/02/2023\")").unwrap(),
+        44929.0
+    );
+}
+
+#[test]
+fn test_datevalue_ddmm_unambiguous() {
+    // 15/01/2023 should be 15-Jan-2023 since 15 cannot be month
+    assert_eq!(
+        eval_formula_raw_number("=DATEVALUE(\"15/01/2023\")").unwrap(),
+        44941.0
+    );
+}
+
+#[test]
+fn test_datevalue_leap_day() {
+    assert_eq!(
+        eval_formula_raw_number("=DATEVALUE(\"29/02/2020\")").unwrap(),
+        43890.0
+    );
+}
+
+#[test]
+fn test_datevalue_year_first_text_month() {
+    assert_eq!(
+        eval_formula_raw_number("=DATEVALUE(\"2023/Jan/15\")").unwrap(),
+        44941.0
+    );
+}
+
+#[test]
+fn test_datevalue_mmdd_with_day_gt_12() {
+    assert_eq!(
+        eval_formula_raw_number("=DATEVALUE(\"6/15/2021\")").unwrap(),
+        44373.0
+    );
+}
+
+#[test]
+fn test_datevalue_error_conditions() {
+    let cases = [
+        "=DATEVALUE(\"31/04/2023\")",   // invalid day (Apr has 30 days)
+        "=DATEVALUE(\"13/13/2023\")",   // invalid month
+        "=DATEVALUE(\"not a date\")",   // non-date text
+    ];
+    for formula in cases {
+        let result = eval_formula(formula);
+        assert_eq!(result, *"#VALUE!", "Expected #VALUE! for {}", formula);
+    }
+}
+
+// Helper to set and evaluate a single DATEDIF call
+fn eval_datedif(unit: &str) -> String {
+    let mut model = new_empty_model();
+    let formula = format!("=DATEDIF(\"2020-01-01\", \"2021-06-15\", \"{}\")", unit);
+    model._set("A1", &formula);
+    model.evaluate();
+    model._get_text("A1")
+}
+
+#[test]
+fn test_datedif_y() {
+    assert_eq!(eval_datedif("Y"), *"1");
+}
+
+#[test]
+fn test_datedif_m() {
+    assert_eq!(eval_datedif("M"), *"17");
+}
+
+#[test]
+fn test_datedif_d() {
+    assert_eq!(eval_datedif("D"), *"531");
+}
+
+#[test]
+fn test_datedif_ym() {
+    assert_eq!(eval_datedif("YM"), *"5");
+}
+
+#[test]
+fn test_datedif_yd() {
+    assert_eq!(eval_datedif("YD"), *"165");
+}
+
+#[test]
+fn test_datedif_md() {
+    assert_eq!(eval_datedif("MD"), *"14");
+}
+
+#[test]
+fn test_datedif_edge_and_error_cases() {
+    let mut model = new_empty_model();
+    // Leap-year spanning
+    model._set("A1", "=DATEDIF(\"28/2/2020\", \"1/3/2020\", \"D\")");
+    // End date before start date => #NUM!
+    model._set("A2", "=DATEDIF(\"1/2/2021\", \"1/1/2021\", \"D\")");
+    // Invalid unit => #VALUE!
+    model._set("A3", "=DATEDIF(\"1/1/2020\", \"1/1/2021\", \"Z\")");
+    model.evaluate();
+
+    assert_eq!(model._get_text("A1"), *"2");
+    assert_eq!(model._get_text("A2"), *"#NUM!");
+    assert_eq!(model._get_text("A3"), *"#VALUE!");
+}
+
+#[test]
+fn test_datedif_mixed_case_unit() {
+    assert_eq!(eval_datedif("yD"), *"165"); // mixed-case should work
+}
+
+#[test]
+fn test_datedif_error_propagation() {
+    // Invalid date in arguments should propagate #VALUE!
+    let mut model = new_empty_model();
+    model._set("A1", "=DATEDIF(\"bad\", \"bad\", \"Y\")");
+    model.evaluate();
+    assert_eq!(model._get_text("A1"), *"#VALUE!");
+}

base/src/test/test_fn_time.rs

@@ -0,0 +1,520 @@
+#![allow(clippy::unwrap_used)]
+
+use crate::test::util::new_empty_model;
+
+// Helper constants for common time values with detailed documentation
+const MIDNIGHT: &str = "0"; // 00:00:00 = 0/24 = 0
+const NOON: &str = "0.5"; // 12:00:00 = 12/24 = 0.5
+const TIME_14_30: &str = "0.604166667"; // 14:30:00 = 14.5/24 ≈ 0.604166667
+const TIME_14_30_45: &str = "0.6046875"; // 14:30:45 = 14.5125/24 = 0.6046875
+const TIME_14_30_59: &str = "0.604849537"; // 14:30:59 (from floored fractional inputs)
+const TIME_23_59_59: &str = "0.999988426"; // 23:59:59 = 23.99972.../24 ≈ 0.999988426
+
+// Excel documentation test values with explanations
+const TIME_2_24_AM: &str = "0.1"; // 2:24 AM = 2.4/24 = 0.1
+const TIME_2_PM: &str = "0.583333333"; // 2:00 PM = 14/24 ≈ 0.583333333
+const TIME_6_45_PM: &str = "0.78125"; // 6:45 PM = 18.75/24 = 0.78125
+const TIME_6_35_AM: &str = "0.274305556"; // 6:35 AM = 6.583333.../24 ≈ 0.274305556
+const TIME_2_30_AM: &str = "0.104166667"; // 2:30 AM = 2.5/24 ≈ 0.104166667
+const TIME_1_AM: &str = "0.041666667"; // 1:00 AM = 1/24 ≈ 0.041666667
+const TIME_9_PM: &str = "0.875"; // 9:00 PM = 21/24 = 0.875
+const TIME_2_AM: &str = "0.083333333"; // 2:00 AM = 2/24 ≈ 0.083333333
+                                       // Additional helper: 1-second past midnight (00:00:01)
+const TIME_00_00_01: &str = "0.000011574"; // 1 second = 1/86400 ≈ 0.000011574
+
+/// Helper function to set up and evaluate a model with time expressions
+fn test_time_expressions(expressions: &[(&str, &str)]) -> crate::model::Model {
+    let mut model = new_empty_model();
+    for (cell, formula) in expressions {
+        model._set(cell, formula);
+    }
+    model.evaluate();
+    model
+}
+
+/// Helper function to test component extraction for a given time value
+/// Returns (hour, minute, second) as strings
+fn test_component_extraction(time_value: &str) -> (String, String, String) {
+    let model = test_time_expressions(&[
+        ("A1", &format!("=HOUR({time_value})")),
+        ("B1", &format!("=MINUTE({time_value})")),
+        ("C1", &format!("=SECOND({time_value})")),
+    ]);
+    (
+        model._get_text("A1").to_string(),
+        model._get_text("B1").to_string(),
+        model._get_text("C1").to_string(),
+    )
+}
+
+#[test]
+fn test_excel_timevalue_compatibility() {
+    // Test cases based on Excel's official documentation and examples
+    let model = test_time_expressions(&[
+        // Excel documentation examples
+        ("A1", "=TIMEVALUE(\"2:24 AM\")"), // Should be 0.1
+        ("A2", "=TIMEVALUE(\"2 PM\")"),    // Should be 0.583333... (14/24)
+        ("A3", "=TIMEVALUE(\"6:45 PM\")"), // Should be 0.78125 (18.75/24)
+        ("A4", "=TIMEVALUE(\"18:45\")"),   // Same as above, 24-hour format
+        // Date-time format (date should be ignored)
+        ("B1", "=TIMEVALUE(\"22-Aug-2011 6:35 AM\")"), // Should be ~0.2743
+        ("B2", "=TIMEVALUE(\"2023-01-01 14:30:00\")"), // Should be 0.604166667
+        // Edge cases that Excel should support
+        ("C1", "=TIMEVALUE(\"12:00 AM\")"),    // Midnight: 0
+        ("C2", "=TIMEVALUE(\"12:00 PM\")"),    // Noon: 0.5
+        ("C3", "=TIMEVALUE(\"11:59:59 PM\")"), // Almost midnight: 0.999988426
+        // Single digit variations
+        ("D1", "=TIMEVALUE(\"1 AM\")"),  // 1:00 AM
+        ("D2", "=TIMEVALUE(\"9 PM\")"),  // 9:00 PM
+        ("D3", "=TIMEVALUE(\"12 AM\")"), // Midnight
+        ("D4", "=TIMEVALUE(\"12 PM\")"), // Noon
+    ]);
+
+    // Excel documentation examples - verify exact values
+    assert_eq!(model._get_text("A1"), *TIME_2_24_AM); // 2:24 AM
+    assert_eq!(model._get_text("A2"), *TIME_2_PM); // 2 PM = 14:00
+    assert_eq!(model._get_text("A3"), *TIME_6_45_PM); // 6:45 PM = 18:45
+    assert_eq!(model._get_text("A4"), *TIME_6_45_PM); // 18:45 (24-hour)
+
+    // Date-time formats (date ignored, extract time only)
+    assert_eq!(model._get_text("B1"), *TIME_6_35_AM); // 6:35 AM ≈ 0.2743
+    assert_eq!(model._get_text("B2"), *TIME_14_30); // 14:30:00
+
+    // Edge cases
+    assert_eq!(model._get_text("C1"), *MIDNIGHT); // 12:00 AM = 00:00
+    assert_eq!(model._get_text("C2"), *NOON); // 12:00 PM = 12:00
+    assert_eq!(model._get_text("C3"), *TIME_23_59_59); // 11:59:59 PM
+
+    // Single digit hours
+    assert_eq!(model._get_text("D1"), *TIME_1_AM); // 1:00 AM
+    assert_eq!(model._get_text("D2"), *TIME_9_PM); // 9:00 PM = 21:00
+    assert_eq!(model._get_text("D3"), *MIDNIGHT); // 12 AM = 00:00
+    assert_eq!(model._get_text("D4"), *NOON); // 12 PM = 12:00
+}
+
+#[test]
+fn test_time_function_basic_cases() {
+    let model = test_time_expressions(&[
+        ("A1", "=TIME(0,0,0)"),    // Midnight
+        ("A2", "=TIME(12,0,0)"),   // Noon
+        ("A3", "=TIME(14,30,0)"),  // 2:30 PM
+        ("A4", "=TIME(23,59,59)"), // Max time
+    ]);
+
+    assert_eq!(model._get_text("A1"), *MIDNIGHT);
+    assert_eq!(model._get_text("A2"), *NOON);
+    assert_eq!(model._get_text("A3"), *TIME_14_30);
+    assert_eq!(model._get_text("A4"), *TIME_23_59_59);
+}
+
+#[test]
+fn test_time_function_normalization() {
+    let model = test_time_expressions(&[
+        ("A1", "=TIME(25,0,0)"),         // Hours > 24 wrap around
+        ("A2", "=TIME(48,0,0)"),         // 48 hours = 0 (2 full days)
+        ("A3", "=TIME(0,90,0)"),         // 90 minutes = 1.5 hours
+        ("A4", "=TIME(0,0,90)"),         // 90 seconds = 1.5 minutes
+        ("A5", "=TIME(14.9,30.9,59.9)"), // Fractional inputs floored to 14:30:59
+    ]);
+
+    assert_eq!(model._get_text("A1"), *TIME_1_AM); // 1:00:00
+    assert_eq!(model._get_text("A2"), *MIDNIGHT); // 0:00:00
+    assert_eq!(model._get_text("A3"), *"0.0625"); // 1:30:00
+    assert_eq!(model._get_text("A4"), *"0.001041667"); // 0:01:30
+    assert_eq!(model._get_text("A5"), *TIME_14_30_59); // 14:30:59 (floored)
+}
+
+#[test]
+fn test_time_function_precision_edge_cases() {
+    let model = test_time_expressions(&[
+        // High precision fractional seconds
+        ("A1", "=TIME(14,30,45.999)"), // Fractional seconds should be floored
+        ("A2", "=SECOND(TIME(14,30,45.999))"), // Should extract 45, not 46
+        // Very large normalization values
+        ("B1", "=TIME(999,999,999)"), // Extreme normalization test
+        ("B2", "=HOUR(999.5)"),       // Multiple days, extract hour from fractional part
+        ("B3", "=MINUTE(999.75)"),    // Multiple days, extract minute
+        // Boundary conditions at rollover points
+        ("C1", "=TIME(24,60,60)"), // Should normalize to next day (00:01:00)
+        ("C2", "=HOUR(0.999999999)"), // Almost 24 hours should be 23
+        ("C3", "=MINUTE(0.999999999)"), // Almost 24 hours, extract minutes
+        ("C4", "=SECOND(0.999999999)"), // Almost 24 hours, extract seconds
+        // Precision at boundaries
+        ("D1", "=TIME(23,59,59.999)"), // Very close to midnight
+        ("D2", "=TIME(0,0,0.001)"),    // Just after midnight
+    ]);
+
+    // Fractional seconds are floored
+    assert_eq!(model._get_text("A2"), *"45"); // 45.999 floored to 45
+
+    // Multiple days should work with rem_euclid
+    assert_eq!(model._get_text("B2"), *"12"); // 999.5 days, hour = 12 (noon)
+
+    // Boundary normalization
+    assert_eq!(model._get_text("C1"), *"0.042361111"); // 24:60:60 = 01:01:00 (normalized)
+    assert_eq!(model._get_text("C2"), *"23"); // Almost 24 hours = 23:xx:xx
+
+    // High precision should be handled correctly
+    let result_d1 = model._get_text("D1").parse::<f64>().unwrap();
+    assert!(result_d1 < 1.0 && result_d1 > 0.999); // Very close to but less than 1.0
+}
+
+#[test]
+fn test_time_function_errors() {
+    let model = test_time_expressions(&[
+        ("A1", "=TIME()"),          // Wrong arg count
+        ("A2", "=TIME(12)"),        // Wrong arg count
+        ("A3", "=TIME(12,30,0,0)"), // Wrong arg count
+        ("B1", "=TIME(-1,0,0)"),    // Negative hour
+        ("B2", "=TIME(0,-1,0)"),    // Negative minute
+        ("B3", "=TIME(0,0,-1)"),    // Negative second
+    ]);
+
+    // Wrong argument count
+    assert_eq!(model._get_text("A1"), *"#ERROR!");
+    assert_eq!(model._get_text("A2"), *"#ERROR!");
+    assert_eq!(model._get_text("A3"), *"#ERROR!");
+
+    // Negative values should return #NUM! error
+    assert_eq!(model._get_text("B1"), *"#NUM!");
+    assert_eq!(model._get_text("B2"), *"#NUM!");
+    assert_eq!(model._get_text("B3"), *"#NUM!");
+}
+
+#[test]
+fn test_timevalue_function_formats() {
+    let model = test_time_expressions(&[
+        // Basic formats
+        ("A1", "=TIMEVALUE(\"14:30\")"),
+        ("A2", "=TIMEVALUE(\"14:30:45\")"),
+        ("A3", "=TIMEVALUE(\"00:00:00\")"),
+        // AM/PM formats
+        ("B1", "=TIMEVALUE(\"2:30 PM\")"),
+        ("B2", "=TIMEVALUE(\"2:30 AM\")"),
+        ("B3", "=TIMEVALUE(\"12:00 PM\")"), // Noon
+        ("B4", "=TIMEVALUE(\"12:00 AM\")"), // Midnight
+        // Single hour with AM/PM (now supported!)
+        ("B5", "=TIMEVALUE(\"2 PM\")"),
+        ("B6", "=TIMEVALUE(\"2 AM\")"),
+        // Date-time formats (extract time only)
+        ("C1", "=TIMEVALUE(\"2023-01-01 14:30:00\")"),
+        ("C2", "=TIMEVALUE(\"2023-01-01T14:30:00\")"),
+        // Whitespace handling
+        ("D1", "=TIMEVALUE(\" 14:30 \")"),
+    ]);
+
+    // Basic formats
+    assert_eq!(model._get_text("A1"), *TIME_14_30);
+    assert_eq!(model._get_text("A2"), *TIME_14_30_45);
+    assert_eq!(model._get_text("A3"), *MIDNIGHT);
+
+    // AM/PM formats
+    assert_eq!(model._get_text("B1"), *TIME_14_30); // 2:30 PM = 14:30
+    assert_eq!(model._get_text("B2"), *TIME_2_30_AM); // 2:30 AM
+    assert_eq!(model._get_text("B3"), *NOON); // 12:00 PM = noon
+    assert_eq!(model._get_text("B4"), *MIDNIGHT); // 12:00 AM = midnight
+
+    // Single hour AM/PM formats (now supported!)
+    assert_eq!(model._get_text("B5"), *TIME_2_PM); // 2 PM = 14:00
+    assert_eq!(model._get_text("B6"), *TIME_2_AM); // 2 AM = 02:00
+
+    // Date-time formats
+    assert_eq!(model._get_text("C1"), *TIME_14_30);
+    assert_eq!(model._get_text("C2"), *TIME_14_30);
+
+    // Whitespace
+    assert_eq!(model._get_text("D1"), *TIME_14_30);
+}
+
+#[test]
+fn test_timevalue_function_errors() {
+    let model = test_time_expressions(&[
+        ("A1", "=TIMEVALUE()"),                 // Wrong arg count
+        ("A2", "=TIMEVALUE(\"14:30\", \"x\")"), // Wrong arg count
+        ("B1", "=TIMEVALUE(\"invalid\")"),      // Invalid format
+        ("B2", "=TIMEVALUE(\"25:00\")"),        // Invalid hour
+        ("B3", "=TIMEVALUE(\"14:70\")"),        // Invalid minute
+        ("B4", "=TIMEVALUE(\"\")"),             // Empty string
+        ("B5", "=TIMEVALUE(\"2PM\")"),          // Missing space (still unsupported)
+    ]);
+
+    // Wrong argument count should return #ERROR!
+    assert_eq!(model._get_text("A1"), *"#ERROR!");
+    assert_eq!(model._get_text("A2"), *"#ERROR!");
+
+    // Invalid formats should return #VALUE!
+    assert_eq!(model._get_text("B1"), *"#VALUE!");
+    assert_eq!(model._get_text("B2"), *"#VALUE!");
+    assert_eq!(model._get_text("B3"), *"#VALUE!");
+    assert_eq!(model._get_text("B4"), *"#VALUE!");
+    assert_eq!(model._get_text("B5"), *"#VALUE!"); // "2PM" no space - not supported
+}
+
+#[test]
+fn test_time_component_extraction_comprehensive() {
+    // Test component extraction using helper function for consistency
+
+    // Test basic time values
+    let test_cases = [
+        (MIDNIGHT, ("0", "0", "0")),         // 00:00:00
+        (NOON, ("12", "0", "0")),            // 12:00:00
+        (TIME_14_30, ("14", "30", "0")),     // 14:30:00
+        (TIME_23_59_59, ("23", "59", "59")), // 23:59:59
+    ];
+
+    for (time_value, expected) in test_cases {
+        let (hour, minute, second) = test_component_extraction(time_value);
+        assert_eq!(hour, expected.0, "Hour mismatch for {time_value}");
+        assert_eq!(minute, expected.1, "Minute mismatch for {time_value}");
+        assert_eq!(second, expected.2, "Second mismatch for {time_value}");
+    }
+
+    // Test multiple days (extract from fractional part)
+    let (hour, minute, second) = test_component_extraction("1.5"); // Day 2, 12:00
+    assert_eq!(
+        (hour, minute, second),
+        ("12".to_string(), "0".to_string(), "0".to_string())
+    );
+
+    let (hour, minute, second) = test_component_extraction("100.604166667"); // Day 101, 14:30
+    assert_eq!(
+        (hour, minute, second),
+        ("14".to_string(), "30".to_string(), "0".to_string())
+    );
+
+    // Test precision at boundaries
+    let (hour, _, _) = test_component_extraction("0.041666666"); // Just under 1:00 AM
+    assert_eq!(hour, "0");
+
+    let (hour, _, _) = test_component_extraction("0.041666667"); // Exactly 1:00 AM
+    assert_eq!(hour, "1");
+
+    let (hour, _, _) = test_component_extraction("0.041666668"); // Just over 1:00 AM
+    assert_eq!(hour, "1");
+
+    // Test very large day values
+    let (hour, minute, second) = test_component_extraction("1000000.25"); // Million days + 6 hours
+    assert_eq!(
+        (hour, minute, second),
+        ("6".to_string(), "0".to_string(), "0".to_string())
+    );
+}
+
+#[test]
+fn test_time_component_function_errors() {
+    let model = test_time_expressions(&[
+        // Wrong argument counts
+        ("A1", "=HOUR()"),       // No arguments
+        ("A2", "=MINUTE()"),     // No arguments
+        ("A3", "=SECOND()"),     // No arguments
+        ("A4", "=HOUR(1, 2)"),   // Too many arguments
+        ("A5", "=MINUTE(1, 2)"), // Too many arguments
+        ("A6", "=SECOND(1, 2)"), // Too many arguments
+        // Negative values should return #NUM!
+        ("B1", "=HOUR(-0.5)"),        // Negative value
+        ("B2", "=MINUTE(-1)"),        // Negative value
+        ("B3", "=SECOND(-1)"),        // Negative value
+        ("B4", "=HOUR(-0.000001)"),   // Slightly negative
+        ("B5", "=MINUTE(-0.000001)"), // Slightly negative
+        ("B6", "=SECOND(-0.000001)"), // Slightly negative
+    ]);
+
+    // Wrong argument count should return #ERROR!
+    assert_eq!(model._get_text("A1"), *"#ERROR!");
+    assert_eq!(model._get_text("A2"), *"#ERROR!");
+    assert_eq!(model._get_text("A3"), *"#ERROR!");
+    assert_eq!(model._get_text("A4"), *"#ERROR!");
+    assert_eq!(model._get_text("A5"), *"#ERROR!");
+    assert_eq!(model._get_text("A6"), *"#ERROR!");
+
+    // Negative values should return #NUM!
+    assert_eq!(model._get_text("B1"), *"#NUM!");
+    assert_eq!(model._get_text("B2"), *"#NUM!");
+    assert_eq!(model._get_text("B3"), *"#NUM!");
+    assert_eq!(model._get_text("B4"), *"#NUM!");
+    assert_eq!(model._get_text("B5"), *"#NUM!");
+    assert_eq!(model._get_text("B6"), *"#NUM!");
+}
+
+#[test]
+fn test_time_functions_integration() {
+    // Test how TIME, TIMEVALUE and component extraction functions work together
+    let model = test_time_expressions(&[
+        // Create times with both functions
+        ("A1", "=TIME(14,30,45)"),
+        ("A2", "=TIMEVALUE(\"14:30:45\")"),
+        // Extract components from TIME function results
+        ("B1", "=HOUR(A1)"),
+        ("B2", "=MINUTE(A1)"),
+        ("B3", "=SECOND(A1)"),
+        // Extract components from TIMEVALUE function results
+        ("C1", "=HOUR(A2)"),
+        ("C2", "=MINUTE(A2)"),
+        ("C3", "=SECOND(A2)"),
+        // Test additional TIME variations
+        ("D1", "=TIME(14,0,0)"), // 14:00:00
+        ("E1", "=HOUR(D1)"),     // Extract hour from 14:00:00
+        ("E2", "=MINUTE(D1)"),   // Extract minute from 14:00:00
+        ("E3", "=SECOND(D1)"),   // Extract second from 14:00:00
+    ]);
+
+    // TIME and TIMEVALUE should produce equivalent results
+    assert_eq!(model._get_text("A1"), model._get_text("A2"));
+
+    // Extracting components should work consistently
+    assert_eq!(model._get_text("B1"), *"14");
+    assert_eq!(model._get_text("B2"), *"30");
+    assert_eq!(model._get_text("B3"), *"45");
+    assert_eq!(model._get_text("C1"), *"14");
+    assert_eq!(model._get_text("C2"), *"30");
+    assert_eq!(model._get_text("C3"), *"45");
+
+    // Components from TIME(14,0,0)
+    assert_eq!(model._get_text("E1"), *"14");
+    assert_eq!(model._get_text("E2"), *"0");
+    assert_eq!(model._get_text("E3"), *"0");
+}
+
+#[test]
+fn test_time_function_extreme_values() {
+    // Test missing edge cases: very large fractional inputs
+    let model = test_time_expressions(&[
+        // Extremely large fractional values to TIME function
+        ("A1", "=TIME(999999.9, 999999.9, 999999.9)"), // Very large fractional inputs
+        ("A2", "=TIME(1e6, 1e6, 1e6)"),                // Scientific notation inputs
+        ("A3", "=TIME(0.000001, 0.000001, 0.000001)"), // Very small fractional inputs
+        // Large day values for component extraction (stress test)
+        ("B1", "=HOUR(999999.999)"), // Almost a million days
+        ("B2", "=MINUTE(999999.999)"),
+        ("B3", "=SECOND(999999.999)"),
+        // Edge case: exactly 1.0 (should be midnight of next day)
+        ("C1", "=HOUR(1.0)"),
+        ("C2", "=MINUTE(1.0)"),
+        ("C3", "=SECOND(1.0)"),
+        // Very high precision values
+        ("D1", "=HOUR(0.999999999999)"), // Almost exactly 24:00:00
+        ("D2", "=MINUTE(0.999999999999)"),
+        ("D3", "=SECOND(0.999999999999)"),
+    ]);
+
+    // Large fractional inputs should be floored and normalized
+    let result_a1 = model._get_text("A1").parse::<f64>().unwrap();
+    assert!(
+        (0.0..1.0).contains(&result_a1),
+        "Result should be valid time fraction"
+    );
+
+    // Component extraction should work with very large values
+    let hour_b1 = model._get_text("B1").parse::<i32>().unwrap();
+    assert!((0..=23).contains(&hour_b1), "Hour should be 0-23");
+
+    // Exactly 1.0 should be midnight (start of next day)
+    assert_eq!(model._get_text("C1"), *"0");
+    assert_eq!(model._get_text("C2"), *"0");
+    assert_eq!(model._get_text("C3"), *"0");
+
+    // Very high precision should still extract valid components
+    let hour_d1 = model._get_text("D1").parse::<i32>().unwrap();
+    assert!((0..=23).contains(&hour_d1), "Hour should be 0-23");
+}
+
+#[test]
+fn test_timevalue_malformed_but_parseable() {
+    // Test missing edge case: malformed but potentially parseable strings
+    let model = test_time_expressions(&[
+        // Test various malformed but potentially parseable time strings
+        ("A1", "=TIMEVALUE(\"14:30:00.123\")"), // Milliseconds (might be truncated)
+        ("A2", "=TIMEVALUE(\"14:30:00.999\")"), // High precision milliseconds
+        ("A3", "=TIMEVALUE(\"02:30:00\")"),     // Leading zero hours
+        ("A4", "=TIMEVALUE(\"2:05:00\")"),      // Single digit hour, zero-padded minute
+        // Boundary cases for AM/PM parsing
+        ("B1", "=TIMEVALUE(\"11:59:59 PM\")"), // Just before midnight
+        ("B2", "=TIMEVALUE(\"12:00:01 AM\")"), // Just after midnight
+        ("B3", "=TIMEVALUE(\"12:00:01 PM\")"), // Just after noon
+        ("B4", "=TIMEVALUE(\"11:59:59 AM\")"), // Just before noon
+        // Test various date-time combinations
+        ("C1", "=TIMEVALUE(\"2023-12-31T23:59:59\")"), // ISO format at year end
+        ("C2", "=TIMEVALUE(\"2023-01-01 00:00:01\")"), // New year, just after midnight
+        // Test potential edge cases that might still be parseable
+        ("D1", "=TIMEVALUE(\"24:00:00\")"), // Should error (invalid hour)
+        ("D2", "=TIMEVALUE(\"23:60:00\")"), // Should error (invalid minute)
+        ("D3", "=TIMEVALUE(\"23:59:60\")"), // Should error (invalid second)
+    ]);
+
+    // Milliseconds are not supported, should return a #VALUE! error like Excel
+    assert_eq!(model._get_text("A1"), *"#VALUE!");
+    assert_eq!(model._get_text("A2"), *"#VALUE!");
+
+    // Leading zeros should work fine
+    assert_eq!(model._get_text("A3"), *TIME_2_30_AM); // 02:30:00 should parse as 2:30:00
+
+    // AM/PM boundary cases should work
+    let result_b1 = model._get_text("B1").parse::<f64>().unwrap();
+    assert!(
+        result_b1 > 0.99 && result_b1 < 1.0,
+        "11:59:59 PM should be very close to 1.0"
+    );
+
+    let result_b2 = model._get_text("B2").parse::<f64>().unwrap();
+    assert!(
+        result_b2 > 0.0 && result_b2 < 0.01,
+        "12:00:01 AM should be very close to 0.0"
+    );
+
+    // ISO 8601 format with "T" separator should be parsed correctly
+    assert_eq!(model._get_text("C1"), *TIME_23_59_59); // 23:59:59 → almost midnight
+    assert_eq!(model._get_text("C2"), *TIME_00_00_01); // 00:00:01 → one second past midnight
+
+    // Time parser normalizes edge cases to midnight (Excel compatibility)
+    assert_eq!(model._get_text("D1"), *"0"); // 24:00:00 = midnight of next day
+    assert_eq!(model._get_text("D2"), *"0"); // 23:60:00 normalizes to 24:00:00 = midnight
+    assert_eq!(model._get_text("D3"), *"0"); // 23:59:60 normalizes to 24:00:00 = midnight
+}
+
+#[test]
+fn test_performance_stress_with_extreme_values() {
+    // Test performance/stress cases with extreme values
+    let model = test_time_expressions(&[
+        // Very large numbers that should still work
+        ("A1", "=TIME(2147483647, 0, 0)"), // Max i32 hours
+        ("A2", "=TIME(0, 2147483647, 0)"), // Max i32 minutes
+        ("A3", "=TIME(0, 0, 2147483647)"), // Max i32 seconds
+        // Component extraction with extreme day values
+        ("B1", "=HOUR(1e15)"), // Very large day number
+        ("B2", "=MINUTE(1e15)"),
+        ("B3", "=SECOND(1e15)"),
+        // Edge of floating point precision
+        ("C1", "=HOUR(1.7976931348623157e+308)"), // Near max f64
+        ("C2", "=HOUR(2.2250738585072014e-308)"), // Near min positive f64
+        // Multiple TIME function calls with large values
+        ("D1", "=TIME(1000000, 1000000, 1000000)"), // Large normalized values
+        ("D2", "=HOUR(D1)"),                        // Extract from large TIME result
+        ("D3", "=MINUTE(D1)"),
+        ("D4", "=SECOND(D1)"),
+    ]);
+
+    // All results should be valid (not errors) even with extreme inputs
+    for cell in ["A1", "A2", "A3", "B1", "B2", "B3", "D1", "D2", "D3", "D4"] {
+        let result = model._get_text(cell);
+        assert!(
+            result != *"#ERROR!" && result != *"#NUM!" && result != *"#VALUE!",
+            "Cell {cell} should not error with extreme values: {result}",
+        );
+    }
+
+    // Results should be mathematically valid
+    let hour_b1 = model._get_text("B1").parse::<i32>().unwrap();
+    let minute_b2 = model._get_text("B2").parse::<i32>().unwrap();
+    let second_b3 = model._get_text("B3").parse::<i32>().unwrap();
+
+    assert!((0..=23).contains(&hour_b1));
+    assert!((0..=59).contains(&minute_b2));
+    assert!((0..=59).contains(&second_b3));
+
+    // TIME function results should be valid time fractions
+    let time_d1 = model._get_text("D1").parse::<f64>().unwrap();
+    assert!(
+        (0.0..1.0).contains(&time_d1),
+        "TIME result should be valid fraction"
+    );
+}

base/src/test/test_networkdays.rs

@@ -0,0 +1,347 @@
+#![allow(clippy::unwrap_used)]
+
+use crate::test::util::new_empty_model;
+
+// Test data: Jan 1-10, 2023 week
+const JAN_1_2023: i32 = 44927; // Sunday
+const JAN_2_2023: i32 = 44928; // Monday
+const JAN_6_2023: i32 = 44932; // Friday
+const JAN_9_2023: i32 = 44935; // Monday
+const JAN_10_2023: i32 = 44936; // Tuesday
+
+#[test]
+fn networkdays_calculates_weekdays_excluding_weekends() {
+    let mut model = new_empty_model();
+
+    model._set("A1", &format!("=NETWORKDAYS({JAN_1_2023},{JAN_10_2023})"));
+    model.evaluate();
+
+    assert_eq!(
+        model._get_text("A1"),
+        "7",
+        "Should count 7 weekdays in 10-day span"
+    );
+}
+
+#[test]
+fn networkdays_handles_reverse_date_order() {
+    let mut model = new_empty_model();
+
+    model._set("A1", &format!("=NETWORKDAYS({JAN_10_2023},{JAN_1_2023})"));
+    model.evaluate();
+
+    assert_eq!(
+        model._get_text("A1"),
+        "-7",
+        "Reversed dates should return negative count"
+    );
+}
+
+#[test]
+fn networkdays_excludes_holidays_from_weekdays() {
+    let mut model = new_empty_model();
+
+    model._set(
+        "A1",
+        &format!("=NETWORKDAYS({JAN_1_2023},{JAN_10_2023},{JAN_9_2023})"),
+    );
+    model.evaluate();
+
+    assert_eq!(
+        model._get_text("A1"),
+        "6",
+        "Should exclude Monday holiday from 7 weekdays"
+    );
+}
+
+#[test]
+fn networkdays_handles_same_start_end_date() {
+    let mut model = new_empty_model();
+
+    model._set("A1", &format!("=NETWORKDAYS({JAN_9_2023},{JAN_9_2023})"));
+    model.evaluate();
+
+    assert_eq!(
+        model._get_text("A1"),
+        "1",
+        "Same weekday date should count as 1 workday"
+    );
+}
+
+#[test]
+fn networkdays_accepts_holiday_ranges() {
+    let mut model = new_empty_model();
+
+    model._set("B1", &JAN_2_2023.to_string());
+    model._set("B2", &JAN_6_2023.to_string());
+    model._set(
+        "A1",
+        &format!("=NETWORKDAYS({JAN_1_2023},{JAN_10_2023},B1:B2)"),
+    );
+    model.evaluate();
+
+    assert_eq!(
+        model._get_text("A1"),
+        "5",
+        "Should exclude 2 holidays from 7 weekdays"
+    );
+}
+
+#[test]
+fn networkdays_intl_uses_standard_weekend_by_default() {
+    let mut model = new_empty_model();
+
+    model._set(
+        "A1",
+        &format!("=NETWORKDAYS.INTL({JAN_1_2023},{JAN_10_2023})"),
+    );
+    model.evaluate();
+
+    assert_eq!(
+        model._get_text("A1"),
+        "7",
+        "Default should be Saturday-Sunday weekend"
+    );
+}
+
+#[test]
+fn networkdays_intl_supports_numeric_weekend_patterns() {
+    let mut model = new_empty_model();
+
+    // Pattern 2 = Sunday-Monday weekend
+    model._set(
+        "A1",
+        &format!("=NETWORKDAYS.INTL({JAN_1_2023},{JAN_10_2023},2)"),
+    );
+    model.evaluate();
+
+    assert_eq!(
+        model._get_text("A1"),
+        "6",
+        "Sunday-Monday weekend should give 6 workdays"
+    );
+}
+
+#[test]
+fn networkdays_intl_supports_single_day_weekends() {
+    let mut model = new_empty_model();
+
+    // Pattern 11 = Sunday only weekend
+    model._set(
+        "A1",
+        &format!("=NETWORKDAYS.INTL({JAN_1_2023},{JAN_10_2023},11)"),
+    );
+    model.evaluate();
+
+    assert_eq!(
+        model._get_text("A1"),
+        "8",
+        "Sunday-only weekend should give 8 workdays"
+    );
+}
+
+#[test]
+fn networkdays_intl_supports_string_weekend_patterns() {
+    let mut model = new_empty_model();
+
+    // "0000110" = Friday-Saturday weekend
+    model._set(
+        "A1",
+        &format!("=NETWORKDAYS.INTL({JAN_1_2023},{JAN_10_2023},\"0000110\")"),
+    );
+    model.evaluate();
+
+    assert_eq!(
+        model._get_text("A1"),
+        "8",
+        "Friday-Saturday weekend should give 8 workdays"
+    );
+}
+
+#[test]
+fn networkdays_intl_no_weekends_counts_all_days() {
+    let mut model = new_empty_model();
+
+    model._set(
+        "A1",
+        &format!("=NETWORKDAYS.INTL({JAN_1_2023},{JAN_10_2023},\"0000000\")"),
+    );
+    model.evaluate();
+
+    assert_eq!(
+        model._get_text("A1"),
+        "10",
+        "No weekends should count all 10 days"
+    );
+}
+
+#[test]
+fn networkdays_intl_combines_custom_weekends_with_holidays() {
+    let mut model = new_empty_model();
+
+    model._set(
+        "A1",
+        &format!("=NETWORKDAYS.INTL({JAN_1_2023},{JAN_10_2023},\"0000110\",{JAN_9_2023})"),
+    );
+    model.evaluate();
+
+    assert_eq!(
+        model._get_text("A1"),
+        "7",
+        "Should exclude both weekend and holiday"
+    );
+}
+
+#[test]
+fn networkdays_validates_argument_count() {
+    let mut model = new_empty_model();
+
+    model._set("A1", "=NETWORKDAYS()");
+    model._set("A2", "=NETWORKDAYS(1,2,3,4)");
+    model._set("A3", "=NETWORKDAYS.INTL()");
+    model._set("A4", "=NETWORKDAYS.INTL(1,2,3,4,5)");
+
+    model.evaluate();
+
+    assert_eq!(model._get_text("A1"), "#ERROR!");
+    assert_eq!(model._get_text("A2"), "#ERROR!");
+    assert_eq!(model._get_text("A3"), "#ERROR!");
+    assert_eq!(model._get_text("A4"), "#ERROR!");
+}
+
+#[test]
+fn networkdays_rejects_invalid_dates() {
+    let mut model = new_empty_model();
+
+    model._set("A1", "=NETWORKDAYS(-1,100)");
+    model._set("A2", "=NETWORKDAYS(1,3000000)");
+    model._set("A3", "=NETWORKDAYS(\"text\",100)");
+
+    model.evaluate();
+
+    assert_eq!(model._get_text("A1"), "#NUM!");
+    assert_eq!(model._get_text("A2"), "#NUM!");
+    assert_eq!(model._get_text("A3"), "#VALUE!");
+}
+
+#[test]
+fn networkdays_intl_rejects_invalid_weekend_patterns() {
+    let mut model = new_empty_model();
+
+    model._set("A1", "=NETWORKDAYS.INTL(1,10,99)");
+    model._set("A2", "=NETWORKDAYS.INTL(1,10,\"111110\")");
+    model._set("A3", "=NETWORKDAYS.INTL(1,10,\"11111000\")");
+    model._set("A4", "=NETWORKDAYS.INTL(1,10,\"1111102\")");
+
+    model.evaluate();
+
+    assert_eq!(model._get_text("A1"), "#NUM!");
+    assert_eq!(model._get_text("A2"), "#VALUE!");
+    assert_eq!(model._get_text("A3"), "#VALUE!");
+    assert_eq!(model._get_text("A4"), "#VALUE!");
+}
+
+#[test]
+fn networkdays_rejects_invalid_holidays() {
+    let mut model = new_empty_model();
+
+    model._set("B1", "invalid");
+    model._set(
+        "A1",
+        &format!("=NETWORKDAYS({JAN_1_2023},{JAN_10_2023},B1)"),
+    );
+    model._set(
+        "A2",
+        &format!("=NETWORKDAYS({JAN_1_2023},{JAN_10_2023},-1)"),
+    );
+
+    model.evaluate();
+
+    assert_eq!(
+        model._get_text("A1"),
+        "#VALUE!",
+        "Should reject non-numeric holidays"
+    );
+    assert_eq!(
+        model._get_text("A2"),
+        "#NUM!",
+        "Should reject out-of-range holidays"
+    );
+}
+
+#[test]
+fn networkdays_handles_weekend_only_periods() {
+    let mut model = new_empty_model();
+
+    let saturday = JAN_1_2023 - 1;
+    model._set("A1", &format!("=NETWORKDAYS({saturday},{JAN_1_2023})"));
+    model.evaluate();
+
+    assert_eq!(
+        model._get_text("A1"),
+        "0",
+        "Weekend-only period should count 0 workdays"
+    );
+}
+
+#[test]
+fn networkdays_ignores_holidays_outside_date_range() {
+    let mut model = new_empty_model();
+
+    let future_holiday = JAN_10_2023 + 100;
+    model._set(
+        "A1",
+        &format!("=NETWORKDAYS({JAN_1_2023},{JAN_10_2023},{future_holiday})"),
+    );
+    model.evaluate();
+
+    assert_eq!(
+        model._get_text("A1"),
+        "7",
+        "Out-of-range holidays should be ignored"
+    );
+}
+
+#[test]
+fn networkdays_handles_empty_holiday_ranges() {
+    let mut model = new_empty_model();
+
+    model._set(
+        "A1",
+        &format!("=NETWORKDAYS({JAN_1_2023},{JAN_10_2023},B1:B3)"),
+    );
+    model.evaluate();
+
+    assert_eq!(
+        model._get_text("A1"),
+        "7",
+        "Empty holiday range should be treated as no holidays"
+    );
+}
+
+#[test]
+fn networkdays_handles_minimum_valid_dates() {
+    let mut model = new_empty_model();
+
+    model._set("A1", "=NETWORKDAYS(1,7)");
+    model.evaluate();
+
+    assert_eq!(
+        model._get_text("A1"),
+        "5",
+        "Should handle earliest Excel dates correctly"
+    );
+}
+
+#[test]
+fn networkdays_handles_large_date_ranges_efficiently() {
+    let mut model = new_empty_model();
+
+    model._set("A1", "=NETWORKDAYS(1,365)");
+    model.evaluate();
+
+    assert!(
+        !model._get_text("A1").starts_with('#'),
+        "Large ranges should not error"
+    );
+}

base/src/test/test_weekday_return_types.rs

@@ -0,0 +1,26 @@
+use crate::test::util::new_empty_model;
+
+#[test]
+fn test_weekday_return_types_11_to_17() {
+    let mut model = new_empty_model();
+
+    // Test date: 44561 corresponds to a Friday (2021-12-31). We verify the
+    // numeric result for each custom week start defined by return_type 11-17.
+    model._set("A1", "=WEEKDAY(44561,11)"); // Monday start
+    model._set("A2", "=WEEKDAY(44561,12)"); // Tuesday start
+    model._set("A3", "=WEEKDAY(44561,13)"); // Wednesday start
+    model._set("A4", "=WEEKDAY(44561,14)"); // Thursday start
+    model._set("A5", "=WEEKDAY(44561,15)"); // Friday start
+    model._set("A6", "=WEEKDAY(44561,16)"); // Saturday start
+    model._set("A7", "=WEEKDAY(44561,17)"); // Sunday start
+
+    model.evaluate();
+
+    assert_eq!(model._get_text("A1"), *"5"); // Mon=1 .. Sun=7 ⇒ Fri=5
+    assert_eq!(model._get_text("A2"), *"4"); // Tue start ⇒ Fri=4
+    assert_eq!(model._get_text("A3"), *"3"); // Wed start ⇒ Fri=3
+    assert_eq!(model._get_text("A4"), *"2"); // Thu start ⇒ Fri=2
+    assert_eq!(model._get_text("A5"), *"1"); // Fri start ⇒ Fri=1
+    assert_eq!(model._get_text("A6"), *"7"); // Sat start ⇒ Fri=7
+    assert_eq!(model._get_text("A7"), *"6"); // Sun start ⇒ Fri=6
+}

base/src/test/test_weeknum_return_types.rs

@@ -0,0 +1,31 @@
+use crate::test::util::new_empty_model;
+
+#[test]
+fn test_weeknum_return_types_11_to_17_and_21() {
+    let mut model = new_empty_model();
+
+    // Date 44561 -> 2021-12-31 (Friday). Previously verified as week 53 (Sunday/Monday start).
+    // We verify that custom week-start codes 11-17 all map to week 53 and ISO variant (21) maps to 52.
+    let formulas = [
+        ("A1", "=WEEKNUM(44561,11)"),
+        ("A2", "=WEEKNUM(44561,12)"),
+        ("A3", "=WEEKNUM(44561,13)"),
+        ("A4", "=WEEKNUM(44561,14)"),
+        ("A5", "=WEEKNUM(44561,15)"),
+        ("A6", "=WEEKNUM(44561,16)"),
+        ("A7", "=WEEKNUM(44561,17)"),
+        ("A8", "=WEEKNUM(44561,21)"), // ISO week numbering
+    ];
+    for (cell, formula) in formulas {
+        model._set(cell, formula);
+    }
+
+    model.evaluate();
+
+    // All 11-17 variations should yield 53
+    for cell in ["A1", "A2", "A3", "A4", "A5", "A6", "A7"] {
+        assert_eq!(model._get_text(cell), *"53", "{cell} should be 53");
+    }
+    // ISO week (return_type 21)
+    assert_eq!(model._get_text("A8"), *"52");
+}

base/src/test/test_yearfrac_basis.rs

@@ -0,0 +1,60 @@
+#![allow(clippy::panic)]
+use crate::{cell::CellValue, test::util::new_empty_model};
+
+#[test]
+fn test_yearfrac_basis_2_actual_360() {
+    let mut model = new_empty_model();
+
+    // Non-leap span of exactly 360 days should result in 1.0
+    model._set("A1", "=YEARFRAC(44561,44921,2)");
+
+    // Leap-year span of 366 days: Jan 1 2020 → Jan 1 2021
+    model._set("A2", "=YEARFRAC(43831,44197,2)");
+
+    // Reverse order should yield negative value
+    model._set("A3", "=YEARFRAC(44921,44561,2)");
+
+    model.evaluate();
+
+    // 360/360
+    assert_eq!(model._get_text("A1"), *"1");
+
+    // 366/360 ≈ 1.0166666667 (tolerance 1e-10)
+    if let Ok(CellValue::Number(v)) = model.get_cell_value_by_ref("Sheet1!A2") {
+        assert!((v - 1.016_666_666_7).abs() < 1e-10);
+    } else {
+        panic!("Expected numeric value in A2");
+    }
+
+    // Negative symmetric of A1
+    assert_eq!(model._get_text("A3"), *"-1");
+}
+
+#[test]
+fn test_yearfrac_basis_3_actual_365() {
+    let mut model = new_empty_model();
+
+    // Non-leap span of exactly 365 days should result in 1.0
+    model._set("B1", "=YEARFRAC(44561,44926,3)");
+
+    // Leap-year span of 366 days
+    model._set("B2", "=YEARFRAC(43831,44197,3)");
+
+    // Same date should be 0
+    model._set("B3", "=YEARFRAC(44561,44561,3)");
+
+    model.evaluate();
+
+    // 365/365
+    assert_eq!(model._get_text("B1"), *"1");
+
+    // 366/365 ≈ 1.002739726 (tolerance 1e-10)
+    if let Ok(CellValue::Number(v)) = model.get_cell_value_by_ref("Sheet1!B2") {
+        assert!((v - 1.002_739_726).abs() < 1e-10);
+    } else {
+        panic!("Expected numeric value in B2");
+    }
+
+    // Same date
+    assert_eq!(model._get_text("B3"), *"0");
+}

base/src/test/user_model/test_clear_cells.rs

@@ -89,3 +89,67 @@ fn clear_all_empty_cell() {
     model.undo().unwrap();
     assert_eq!(model.get_formatted_cell_value(0, 1, 1), Ok("".to_string()));
 }
+
+#[test]
+fn issue_454() {
+    let mut model = UserModel::new_empty("model", "en", "UTC").unwrap();
+    model
+        .set_user_input(
+            0,
+            1,
+            1,
+            "Le presbytère n'a rien perdu de son charme, ni le jardin de son éclat.",
+        )
+        .unwrap();
+    model.set_user_input(0, 1, 2, "=ISTEXT(A1)").unwrap();
+    assert_eq!(
+        model.get_formatted_cell_value(0, 1, 2),
+        Ok("TRUE".to_string())
+    );
+    model
+        .range_clear_contents(&Area {
+            sheet: 0,
+            row: 1,
+            column: 1,
+            width: 1,
+            height: 1,
+        })
+        .unwrap();
+    assert_eq!(
+        model.get_formatted_cell_value(0, 1, 2),
+        Ok("FALSE".to_string())
+    );
+    model.undo().unwrap();
+}
+
+#[test]
+fn issue_454b() {
+    let mut model = UserModel::new_empty("model", "en", "UTC").unwrap();
+    model
+        .set_user_input(
+            0,
+            1,
+            1,
+            "Le presbytère n'a rien perdu de son charme, ni le jardin de son éclat.",
+        )
+        .unwrap();
+    model.set_user_input(0, 1, 2, "=ISTEXT(A1)").unwrap();
+    assert_eq!(
+        model.get_formatted_cell_value(0, 1, 2),
+        Ok("TRUE".to_string())
+    );
+    model
+        .range_clear_all(&Area {
+            sheet: 0,
+            row: 1,
+            column: 1,
+            width: 1,
+            height: 1,
+        })
+        .unwrap();
+    assert_eq!(
+        model.get_formatted_cell_value(0, 1, 2),
+        Ok("FALSE".to_string())
+    );
+    model.undo().unwrap();
+}

base/src/user_model/common.rs

@@ -627,6 +627,7 @@ impl UserModel {
             }
         }
         self.push_diff_list(diff_list);
+        self.evaluate_if_not_paused();
         Ok(())
     }
 
@@ -656,6 +657,7 @@ impl UserModel {
             }
         }
         self.push_diff_list(diff_list);
+        self.evaluate_if_not_paused();
         Ok(())
     }
 

bindings/nodejs/Cargo.toml

@@ -1,7 +1,7 @@
 [package]
 edition = "2021"
 name = "ironcalc_nodejs"
-version = "0.5.0"
+version = "0.6.0"
 
 [lib]
 crate-type = ["cdylib"]
@@ -10,7 +10,7 @@ crate-type = ["cdylib"]
 # Default enable napi4 feature, see https://nodejs.org/api/n-api.html#node-api-version-matrix
 napi = { version = "2.12.2", default-features = false, features = ["napi4", "serde-json"] }
 napi-derive = "2.12.2"
-ironcalc = { path = "../../xlsx", version = "0.5.0" }
+ironcalc = { path = "../../xlsx", version = "0.6.0" }
 serde = { version = "1.0", features = ["derive"] }
 
 [build-dependencies]

bindings/python/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "pyroncalc"
-version = "0.5.7"
+version = "0.6.0"
 edition = "2021"
 
 
@@ -12,7 +12,7 @@ crate-type = ["cdylib"]
 [dependencies]
 serde = { version = "1.0", features = ["derive"] }
 serde_json = "1.0"
-xlsx = { package= "ironcalc", path = "../../xlsx", version = "0.5.0" }
+xlsx = { package= "ironcalc", path = "../../xlsx", version = "0.6.0" }
 pyo3 = { version = "0.25", features = ["extension-module"] }
 bitcode = "0.6.3"
 

bindings/python/pyproject.toml

@@ -1,6 +1,6 @@
 [project]
 name = "ironcalc"
-version = "0.5.7"
+version = "0.6.0"
 description = "Create, edit and evaluate Excel spreadsheets"
 requires-python = ">=3.10"
 keywords = [

bindings/wasm/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "wasm"
-version = "0.5.0"
+version = "0.6.0"
 authors = ["Nicolas Hatcher <nicolas@theuniverse.today>"]
 description = "IronCalc Web bindings"
 license = "MIT/Apache-2.0"
@@ -14,7 +14,7 @@ crate-type = ["cdylib"]
 # Uses `../ironcalc/base` when used locally, and uses
 # the inicated version from crates.io when published.
 # https://doc.rust-lang.org/cargo/reference/specifying-dependencies.html#multiple-locations
-ironcalc_base = { path = "../../base", version = "0.5", features = ["use_regex_lite"] }
+ironcalc_base = { path = "../../base", version = "0.6", features = ["use_regex_lite"] }
 serde = { version = "1.0", features = ["derive"] }
 wasm-bindgen = "0.2.100"
 serde-wasm-bindgen = "0.4"

docker-compose.yml

@@ -0,0 +1,12 @@
+services:
+  server:
+    build:
+      context: .
+      target: server-runtime
+
+  caddy:
+    build:
+      context: .
+      target: caddy-runtime
+    ports:
+      - "2080:2080"

docs/src/functions/date-and-time.md

@@ -12,27 +12,27 @@ You can track the progress in this [GitHub issue](https://github.com/ironcalc/Ir
 | Function         | Status                                         | Documentation |
 | ---------------- | ---------------------------------------------- | ------------- |
 | DATE             | <Badge type="tip" text="Available" />          | –             |
-| DATEDIF          | <Badge type="info" text="Not implemented yet" /> | –             |
+| DATEDIF          | <Badge type="tip" text="Available" />          | [DATEDIF](date_and_time/datedif) |
-| DATEVALUE        | <Badge type="info" text="Not implemented yet" /> | –             |
+| DATEVALUE        | <Badge type="tip" text="Available" />          | [DATEVALUE](date_and_time/datevalue) |
 | DAY              | <Badge type="tip" text="Available" />          | [DAY](date_and_time/day) |
-| DAYS             | <Badge type="info" text="Not implemented yet" /> | –             |
+| DAYS             | <Badge type="tip" text="Available" />          | –             |
-| DAYS360          | <Badge type="info" text="Not implemented yet" /> | –             |
+| DAYS360          | <Badge type="tip" text="Available" />          | –             |
 | EDATE            | <Badge type="tip" text="Available" />          | –             |
 | EOMONTH          | <Badge type="tip" text="Available" />          | –             |
-| HOUR             | <Badge type="info" text="Not implemented yet" /> | –             |
+| HOUR             | <Badge type="tip" text="Available" />          | [HOUR](date_and_time/hour) |
-| ISOWEEKNUM       | <Badge type="info" text="Not implemented yet" /> | –             |
+| ISOWEEKNUM       | <Badge type="tip" text="Available" />          | –             |
-| MINUTE           | <Badge type="info" text="Not implemented yet" /> | –             |
+| MINUTE           | <Badge type="tip" text="Available" />          | [MINUTE](date_and_time/minute) |
 | MONTH            | <Badge type="tip" text="Available" />          | [MONTH](date_and_time/month) |
-| NETWORKDAYS      | <Badge type="info" text="Not implemented yet" /> | –             |
+| NETWORKDAYS      | <Badge type="tip" text="Available" />          | [NETWORKDAYS](date_and_time/networkdays) |
-| NETWORKDAYS.INTL | <Badge type="info" text="Not implemented yet" /> | –             |
+| NETWORKDAYS.INTL | <Badge type="tip" text="Available" />          | [NETWORKDAYS.INTL](date_and_time/networkdays.intl) |
 | NOW              | <Badge type="tip" text="Available" />          | –             |
-| SECOND           | <Badge type="info" text="Not implemented yet" /> | –             |
+| SECOND           | <Badge type="tip" text="Available" />          | [SECOND](date_and_time/second) |
-| TIME             | <Badge type="info" text="Not implemented yet" /> | –             |
+| TIME             | <Badge type="tip" text="Available" />          | [TIME](date_and_time/time) |
-| TIMEVALUE        | <Badge type="info" text="Not implemented yet" /> | –             |
+| TIMEVALUE        | <Badge type="tip" text="Available" />          | [TIMEVALUE](date_and_time/timevalue) |
 | TODAY            | <Badge type="tip" text="Available" />          | –             |
-| WEEKDAY          | <Badge type="info" text="Not implemented yet" /> | –             |
+| WEEKDAY          | <Badge type="tip" text="Available" />          | –             |
-| WEEKNUM          | <Badge type="info" text="Not implemented yet" /> | –             |
+| WEEKNUM          | <Badge type="tip" text="Available" />          | –             |
-| WORKDAY          | <Badge type="info" text="Not implemented yet" /> | –             |
+| WORKDAY          | <Badge type="tip" text="Available" />          | –             |
-| WORKDAY.INTL     | <Badge type="info" text="Not implemented yet" /> | –             |
+| WORKDAY.INTL     | <Badge type="tip" text="Available" />          | –             |
 | YEAR             | <Badge type="tip" text="Available" />          | [YEAR](date_and_time/year) |
-| YEARFRAC         | <Badge type="info" text="Not implemented yet" /> | –             |
+| YEARFRAC         | <Badge type="tip" text="Available" />          | –             |

docs/src/functions/date_and_time/datedif.md

@@ -7,6 +7,5 @@ lang: en-US
 # DATEDIF
 
 ::: warning
-🚧 This function is not yet available in IronCalc.
+🚧 This function is implemented but currently lacks detailed documentation. For guidance, you may refer to the equivalent functionality in [Microsoft Excel documentation](https://support.microsoft.com/en-us/office/excel-functions-by-category-5f91f4e9-7b42-46d2-9bd1-63f26a86c0eb).
-[Follow development here](https://github.com/ironcalc/IronCalc/labels/Functions)
 :::

docs/src/functions/date_and_time/datevalue.md

@@ -7,6 +7,5 @@ lang: en-US
 # DATEVALUE
 
 ::: warning
-🚧 This function is not yet available in IronCalc.
+🚧 This function is implemented but currently lacks detailed documentation. For guidance, you may refer to the equivalent functionality in [Microsoft Excel documentation](https://support.microsoft.com/en-us/office/excel-functions-by-category-5f91f4e9-7b42-46d2-9bd1-63f26a86c0eb).
-[Follow development here](https://github.com/ironcalc/IronCalc/labels/Functions)
 :::

docs/src/functions/date_and_time/days.md

@@ -7,6 +7,5 @@ lang: en-US
 # DAYS
 
 ::: warning
-🚧 This function is not yet available in IronCalc.
+🚧 This function is implemented but currently lacks detailed documentation. For guidance, you may refer to the equivalent functionality in [Microsoft Excel documentation](https://support.microsoft.com/en-us/office/excel-functions-by-category-5f91f4e9-7b42-46d2-9bd1-63f26a86c0eb).
-[Follow development here](https://github.com/ironcalc/IronCalc/labels/Functions)
 :::

docs/src/functions/date_and_time/days360.md

@@ -7,6 +7,5 @@ lang: en-US
 # DAYS360
 
 ::: warning
-🚧 This function is not yet available in IronCalc.
+🚧 This function is implemented but currently lacks detailed documentation. For guidance, you may refer to the equivalent functionality in [Microsoft Excel documentation](https://support.microsoft.com/en-us/office/excel-functions-by-category-5f91f4e9-7b42-46d2-9bd1-63f26a86c0eb).
-[Follow development here](https://github.com/ironcalc/IronCalc/labels/Functions)
 :::

docs/src/functions/date_and_time/hour.md

@@ -7,6 +7,6 @@ lang: en-US
 # HOUR
 
 ::: warning
-🚧 This function is not yet available in IronCalc.
+**Note:** This draft page is under construction 🚧
-[Follow development here](https://github.com/ironcalc/IronCalc/labels/Functions)
+The HOUR function is implemented and available in IronCalc.
 :::

docs/src/functions/date_and_time/isoweeknum.md

@@ -7,6 +7,5 @@ lang: en-US
 # ISOWEEKNUM
 
 ::: warning
-🚧 This function is not yet available in IronCalc.
+🚧 This function is implemented but currently lacks detailed documentation. For guidance, you may refer to the equivalent functionality in [Microsoft Excel documentation](https://support.microsoft.com/en-us/office/excel-functions-by-category-5f91f4e9-7b42-46d2-9bd1-63f26a86c0eb).
-[Follow development here](https://github.com/ironcalc/IronCalc/labels/Functions)
 :::

docs/src/functions/date_and_time/minute.md

@@ -7,6 +7,6 @@ lang: en-US
 # MINUTE
 
 ::: warning
-🚧 This function is not yet available in IronCalc.
+**Note:** This draft page is under construction 🚧
-[Follow development here](https://github.com/ironcalc/IronCalc/labels/Functions)
+The MINUTE function is implemented and available in IronCalc.
 :::

docs/src/functions/date_and_time/networkdays.intl.md

@@ -4,9 +4,73 @@ outline: deep
 lang: en-US
 ---
 
-# NETWORKDAYS.INTL
+# NETWORKDAYS.INTL function
 
 ::: warning
-🚧 This function is not yet available in IronCalc.
+**Note:** This draft page is under construction 🚧
-[Follow development here](https://github.com/ironcalc/IronCalc/labels/Functions)
 :::
+
+## Overview
+NETWORKDAYS.INTL is a function of the Date and Time category that calculates the number of working days between two dates, with customizable weekend definitions and optionally specified holidays.
+
+## Usage
+
+### Syntax
+**NETWORKDAYS.INTL(<span title="Number" style="color:#1E88E5">start_date</span>, <span title="Number" style="color:#1E88E5">end_date</span>, [<span title="Number or String" style="color:#4CAF50">weekend</span>], [<span title="Array" style="color:#E91E63">holidays</span>]) => <span title="Number" style="color:#1E88E5">workdays</span>**
+
+### Argument descriptions
+* *start_date* ([number](/features/value-types#numbers), required). The start date expressed as a [serial number](/features/serial-numbers.md).
+* *end_date* ([number](/features/value-types#numbers), required). The end date expressed as a [serial number](/features/serial-numbers.md).
+* *weekend* ([number](/features/value-types#numbers) or [string](/features/value-types#strings), optional). Defines which days are considered weekends. Default is 1 (Saturday-Sunday).
+* *holidays* ([array](/features/value-types#arrays) or [range](/features/ranges), optional). A list of dates to exclude from the calculation, expressed as serial numbers.
+
+### Weekend parameter options
+The _weekend_ parameter can be specified in two ways:
+
+**Numeric codes:**
+- 1 (default): Saturday and Sunday
+- 2: Sunday and Monday
+- 3: Monday and Tuesday
+- 4: Tuesday and Wednesday
+- 5: Wednesday and Thursday
+- 6: Thursday and Friday
+- 7: Friday and Saturday
+- 11: Sunday only
+- 12: Monday only
+- 13: Tuesday only
+- 14: Wednesday only
+- 15: Thursday only
+- 16: Friday only
+- 17: Saturday only
+
+**String pattern:** A 7-character string of "0" and "1" where "1" indicates a weekend day. The string represents Monday through Sunday. For example, "0000011" means Saturday and Sunday are weekends.
+
+### Additional guidance
+- If the supplied _start_date_ and _end_date_ arguments have fractional parts, NETWORKDAYS.INTL uses their [floor values](https://en.wikipedia.org/wiki/Floor_and_ceiling_functions).
+- If _start_date_ is later than _end_date_, the function returns a negative number.
+- Empty cells in the _holidays_ array are ignored.
+- The calculation includes both the start and end dates if they are workdays.
+
+### Returned value
+NETWORKDAYS.INTL returns a [number](/features/value-types#numbers) representing the count of working days between the two dates.
+
+### Error conditions
+* In common with many other IronCalc functions, NETWORKDAYS.INTL propagates errors that are found in its arguments.
+* If fewer than 2 or more than 4 arguments are supplied, then NETWORKDAYS.INTL returns the [`#ERROR!`](/features/error-types.md#error) error.
+* If the *start_date* or *end_date* arguments are not (or cannot be converted to) [numbers](/features/value-types#numbers), then NETWORKDAYS.INTL returns the [`#VALUE!`](/features/error-types.md#value) error.
+* If the *start_date* or *end_date* values are outside the valid date range, then NETWORKDAYS.INTL returns the [`#NUM!`](/features/error-types.md#num) error.
+* If the *weekend* parameter is an invalid numeric code or an improperly formatted string, then NETWORKDAYS.INTL returns the [`#NUM!`](/features/error-types.md#num) or [`#VALUE!`](/features/error-types.md#value) error.
+* If the *holidays* array contains non-numeric values, then NETWORKDAYS.INTL returns the [`#VALUE!`](/features/error-types.md#value) error.
+
+<!--@include: ../markdown-snippets/error-type-details.txt-->
+
+## Details
+IronCalc utilizes Rust's [chrono](https://docs.rs/chrono/latest/chrono/) crate to implement the NETWORKDAYS.INTL function. This function provides more flexibility than NETWORKDAYS by allowing custom weekend definitions.
+
+## Examples
+[See some examples in IronCalc](https://app.ironcalc.com/?example=networkdays-intl).
+
+## Links
+* See also IronCalc's [NETWORKDAYS](/functions/date_and_time/networkdays.md) function for the basic version with fixed weekends.
+* Visit Microsoft Excel's [NETWORKDAYS.INTL function](https://support.microsoft.com/en-us/office/networkdays-intl-function-a9b26239-4f20-46a1-9ab8-4e925bfd5e28) page.
+* Both [Google Sheets](https://support.google.com/docs/answer/3093019) and [LibreOffice Calc](https://wiki.documentfoundation.org/Documentation/Calc_Functions/NETWORKDAYS.INTL) provide versions of the NETWORKDAYS.INTL function.

docs/src/functions/date_and_time/networkdays.md

@@ -4,9 +4,51 @@ outline: deep
 lang: en-US
 ---
 
-# NETWORKDAYS
+# NETWORKDAYS function
 
 ::: warning
-🚧 This function is not yet available in IronCalc.
+**Note:** This draft page is under construction 🚧
-[Follow development here](https://github.com/ironcalc/IronCalc/labels/Functions)
 :::
+
+## Overview
+NETWORKDAYS is a function of the Date and Time category that calculates the number of working days between two dates, excluding weekends (Saturday and Sunday by default) and optionally specified holidays.
+
+## Usage
+
+### Syntax
+**NETWORKDAYS(<span title="Number" style="color:#1E88E5">start_date</span>, <span title="Number" style="color:#1E88E5">end_date</span>, [<span title="Array" style="color:#E91E63">holidays</span>]) => <span title="Number" style="color:#1E88E5">workdays</span>**
+
+### Argument descriptions
+* *start_date* ([number](/features/value-types#numbers), required). The start date expressed as a [serial number](/features/serial-numbers.md).
+* *end_date* ([number](/features/value-types#numbers), required). The end date expressed as a [serial number](/features/serial-numbers.md).
+* *holidays* ([array](/features/value-types#arrays) or [range](/features/ranges), optional). A list of dates to exclude from the calculation, expressed as serial numbers.
+
+### Additional guidance
+- If the supplied _start_date_ and _end_date_ arguments have fractional parts, NETWORKDAYS uses their [floor values](https://en.wikipedia.org/wiki/Floor_and_ceiling_functions).
+- If _start_date_ is later than _end_date_, the function returns a negative number.
+- Weekend days are Saturday and Sunday by default. Use [NETWORKDAYS.INTL](networkdays.intl) for custom weekend definitions.
+- Empty cells in the _holidays_ array are ignored.
+- The calculation includes both the start and end dates if they are workdays.
+
+### Returned value
+NETWORKDAYS returns a [number](/features/value-types#numbers) representing the count of working days between the two dates.
+
+### Error conditions
+* In common with many other IronCalc functions, NETWORKDAYS propagates errors that are found in its arguments.
+* If fewer than 2 or more than 3 arguments are supplied, then NETWORKDAYS returns the [`#ERROR!`](/features/error-types.md#error) error.
+* If the *start_date* or *end_date* arguments are not (or cannot be converted to) [numbers](/features/value-types#numbers), then NETWORKDAYS returns the [`#VALUE!`](/features/error-types.md#value) error.
+* If the *start_date* or *end_date* values are outside the valid date range, then NETWORKDAYS returns the [`#NUM!`](/features/error-types.md#num) error.
+* If the *holidays* array contains non-numeric values, then NETWORKDAYS returns the [`#VALUE!`](/features/error-types.md#value) error.
+
+<!--@include: ../markdown-snippets/error-type-details.txt-->
+
+## Details
+IronCalc utilizes Rust's [chrono](https://docs.rs/chrono/latest/chrono/) crate to implement the NETWORKDAYS function. The function treats Saturday and Sunday as weekend days.
+
+## Examples
+[See some examples in IronCalc](https://app.ironcalc.com/?example=networkdays).
+
+## Links
+* See also IronCalc's [NETWORKDAYS.INTL](/functions/date_and_time/networkdays.intl.md) function for custom weekend definitions.
+* Visit Microsoft Excel's [NETWORKDAYS function](https://support.microsoft.com/en-us/office/networkdays-function-48e717bf-a7a3-495f-969e-5005e3eb18e7) page.
+* Both [Google Sheets](https://support.google.com/docs/answer/3093018) and [LibreOffice Calc](https://wiki.documentfoundation.org/Documentation/Calc_Functions/NETWORKDAYS) provide versions of the NETWORKDAYS function.

docs/src/functions/date_and_time/second.md

@@ -7,6 +7,6 @@ lang: en-US
 # SECOND
 
 ::: warning
-🚧 This function is not yet available in IronCalc.
+**Note:** This draft page is under construction 🚧
-[Follow development here](https://github.com/ironcalc/IronCalc/labels/Functions)
+The SECOND function is implemented and available in IronCalc.
 :::

docs/src/functions/date_and_time/time.md

@@ -7,6 +7,6 @@ lang: en-US
 # TIME
 
 ::: warning
-🚧 This function is not yet available in IronCalc.
+**Note:** This draft page is under construction 🚧
-[Follow development here](https://github.com/ironcalc/IronCalc/labels/Functions)
+The TIME function is implemented and available in IronCalc.
 :::

docs/src/functions/date_and_time/timevalue.md

@@ -7,6 +7,6 @@ lang: en-US
 # TIMEVALUE
 
 ::: warning
-🚧 This function is not yet available in IronCalc.
+**Note:** This draft page is under construction 🚧
-[Follow development here](https://github.com/ironcalc/IronCalc/labels/Functions)
+The TIMEVALUE function is implemented and available in IronCalc.
 :::

docs/src/functions/date_and_time/weekday.md

@@ -7,6 +7,5 @@ lang: en-US
 # WEEKDAY
 
 ::: warning
-🚧 This function is not yet available in IronCalc.
+🚧 This function is implemented but currently lacks detailed documentation. For guidance, you may refer to the equivalent functionality in [Microsoft Excel documentation](https://support.microsoft.com/en-us/office/excel-functions-by-category-5f91f4e9-7b42-46d2-9bd1-63f26a86c0eb).
-[Follow development here](https://github.com/ironcalc/IronCalc/labels/Functions)
 :::

docs/src/functions/date_and_time/weeknum.md

@@ -7,6 +7,5 @@ lang: en-US
 # WEEKNUM
 
 ::: warning
-🚧 This function is not yet available in IronCalc.
+🚧 This function is implemented but currently lacks detailed documentation. For guidance, you may refer to the equivalent functionality in [Microsoft Excel documentation](https://support.microsoft.com/en-us/office/excel-functions-by-category-5f91f4e9-7b42-46d2-9bd1-63f26a86c0eb).
-[Follow development here](https://github.com/ironcalc/IronCalc/labels/Functions)
 :::

docs/src/functions/date_and_time/workday.intl.md

@@ -7,6 +7,5 @@ lang: en-US
 # WORKDAY.INTL
 
 ::: warning
-🚧 This function is not yet available in IronCalc.
+🚧 This function is implemented but currently lacks detailed documentation. For guidance, you may refer to the equivalent functionality in [Microsoft Excel documentation](https://support.microsoft.com/en-us/office/excel-functions-by-category-5f91f4e9-7b42-46d2-9bd1-63f26a86c0eb).
-[Follow development here](https://github.com/ironcalc/IronCalc/labels/Functions)
 :::

docs/src/functions/date_and_time/workday.md

@@ -7,6 +7,5 @@ lang: en-US
 # WORKDAY
 
 ::: warning
-🚧 This function is not yet available in IronCalc.
+🚧 This function is implemented but currently lacks detailed documentation. For guidance, you may refer to the equivalent functionality in [Microsoft Excel documentation](https://support.microsoft.com/en-us/office/excel-functions-by-category-5f91f4e9-7b42-46d2-9bd1-63f26a86c0eb).
-[Follow development here](https://github.com/ironcalc/IronCalc/labels/Functions)
 :::

docs/src/functions/date_and_time/yearfrac.md

@@ -7,6 +7,5 @@ lang: en-US
 # YEARFRAC
 
 ::: warning
-🚧 This function is not yet available in IronCalc.
+🚧 This function is implemented but currently lacks detailed documentation. For guidance, you may refer to the equivalent functionality in [Microsoft Excel documentation](https://support.microsoft.com/en-us/office/excel-functions-by-category-5f91f4e9-7b42-46d2-9bd1-63f26a86c0eb).
-[Follow development here](https://github.com/ironcalc/IronCalc/labels/Functions)
 :::

docs/src/web-application/managing-workbooks.md

@@ -0,0 +1,18 @@
+---
+layout: doc
+outline: deep
+lang: en-US
+---
+
+# Managing Workbooks
+
+All your created sheets can be accessed from the **Workbook Sidebar**. To display it, click the button in the top-left corner of the window. From there, you can:
+
+- View all existing workbooks, ordered by date (today, last 30 days, and older)
+- Create new blank workbooks
+- Download the existing workbook as .xlsx
+- Pin workbooks to the top of the list
+- Duplicate workbooks
+- Delete workbooks
+
+This helps you keep your workbooks organized and makes sharing simple and straightforward.

docs/src/web-application/sharing-files.md

@@ -26,12 +26,3 @@ IronCalc makes it easy to share your files with others. Follow these steps to sh
 
 - **Changes in the Shared Version**:  
   Any modifications made in the shared sheet (even if it’s an existing sheet) will **not** overwrite or affect the original sheet.
-
-## Managing Sheets
-
-All your created sheets can be accessed from the **"File"** section in the top-left corner of the window. From here, you can:
-
-- View all existing sheets.
-- Delete sheets as needed.
-
-This helps you keep your files organized and makes sharing simple and straightforward.

webapp/IronCalc/src/components/FormatMenu/FormatMenu.tsx

@@ -1,8 +1,9 @@
 import { Menu, MenuItem, styled } from "@mui/material";
+import { Check } from "lucide-react";
 import { type ComponentProps, useCallback, useRef, useState } from "react";
 import { useTranslation } from "react-i18next";
 import FormatPicker from "./FormatPicker";
-import { NumberFormats } from "./formatUtil";
+import { KNOWN_FORMATS, NumberFormats } from "./formatUtil";
 
 type FormatMenuProps = {
   children: React.ReactNode;
@@ -26,6 +27,8 @@ const FormatMenu = (properties: FormatMenuProps) => {
     [properties.onChange],
   );
 
+  const isCustomFormat = !KNOWN_FORMATS.has(properties.numFmt);
+
   return (
     <>
       <ChildrenWrapper
@@ -48,11 +51,17 @@ const FormatMenu = (properties: FormatMenuProps) => {
         }}
       >
         <MenuItemWrapper onClick={(): void => onSelect(NumberFormats.AUTO)}>
-          <MenuItemText>{t("toolbar.format_menu.auto")}</MenuItemText>
+          <MenuItemText>
+            <CheckIcon $active={properties.numFmt === NumberFormats.AUTO} />
+            {t("toolbar.format_menu.auto")}
+          </MenuItemText>
         </MenuItemWrapper>
         <MenuDivider />
         <MenuItemWrapper onClick={(): void => onSelect(NumberFormats.NUMBER)}>
-          <MenuItemText>{t("toolbar.format_menu.number")}</MenuItemText>
+          <MenuItemText>
+            <CheckIcon $active={properties.numFmt === NumberFormats.NUMBER} />
+            {t("toolbar.format_menu.number")}
+          </MenuItemText>
           <MenuItemExample>
             {t("toolbar.format_menu.number_example")}
           </MenuItemExample>
@@ -60,7 +69,12 @@ const FormatMenu = (properties: FormatMenuProps) => {
         <MenuItemWrapper
           onClick={(): void => onSelect(NumberFormats.PERCENTAGE)}
         >
-          <MenuItemText>{t("toolbar.format_menu.percentage")}</MenuItemText>
+          <MenuItemText>
+            <CheckIcon
+              $active={properties.numFmt === NumberFormats.PERCENTAGE}
+            />
+            {t("toolbar.format_menu.percentage")}
+          </MenuItemText>
           <MenuItemExample>
             {t("toolbar.format_menu.percentage_example")}
           </MenuItemExample>
@@ -70,7 +84,12 @@ const FormatMenu = (properties: FormatMenuProps) => {
         <MenuItemWrapper
           onClick={(): void => onSelect(NumberFormats.CURRENCY_EUR)}
         >
-          <MenuItemText>{t("toolbar.format_menu.currency_eur")}</MenuItemText>
+          <MenuItemText>
+            <CheckIcon
+              $active={properties.numFmt === NumberFormats.CURRENCY_EUR}
+            />
+            {t("toolbar.format_menu.currency_eur")}
+          </MenuItemText>
           <MenuItemExample>
             {t("toolbar.format_menu.currency_eur_example")}
           </MenuItemExample>
@@ -78,7 +97,12 @@ const FormatMenu = (properties: FormatMenuProps) => {
         <MenuItemWrapper
           onClick={(): void => onSelect(NumberFormats.CURRENCY_USD)}
         >
-          <MenuItemText>{t("toolbar.format_menu.currency_usd")}</MenuItemText>
+          <MenuItemText>
+            <CheckIcon
+              $active={properties.numFmt === NumberFormats.CURRENCY_USD}
+            />
+            {t("toolbar.format_menu.currency_usd")}
+          </MenuItemText>
           <MenuItemExample>
             {t("toolbar.format_menu.currency_usd_example")}
           </MenuItemExample>
@@ -86,7 +110,12 @@ const FormatMenu = (properties: FormatMenuProps) => {
         <MenuItemWrapper
           onClick={(): void => onSelect(NumberFormats.CURRENCY_GBP)}
         >
-          <MenuItemText>{t("toolbar.format_menu.currency_gbp")}</MenuItemText>
+          <MenuItemText>
+            <CheckIcon
+              $active={properties.numFmt === NumberFormats.CURRENCY_GBP}
+            />
+            {t("toolbar.format_menu.currency_gbp")}
+          </MenuItemText>
           <MenuItemExample>
             {t("toolbar.format_menu.currency_gbp_example")}
           </MenuItemExample>
@@ -96,7 +125,12 @@ const FormatMenu = (properties: FormatMenuProps) => {
         <MenuItemWrapper
           onClick={(): void => onSelect(NumberFormats.DATE_SHORT)}
         >
-          <MenuItemText>{t("toolbar.format_menu.date_short")}</MenuItemText>
+          <MenuItemText>
+            <CheckIcon
+              $active={properties.numFmt === NumberFormats.DATE_SHORT}
+            />
+            {t("toolbar.format_menu.date_short")}
+          </MenuItemText>
           <MenuItemExample>
             {t("toolbar.format_menu.date_short_example")}
           </MenuItemExample>
@@ -104,7 +138,12 @@ const FormatMenu = (properties: FormatMenuProps) => {
         <MenuItemWrapper
           onClick={(): void => onSelect(NumberFormats.DATE_LONG)}
         >
-          <MenuItemText>{t("toolbar.format_menu.date_long")}</MenuItemText>
+          <MenuItemText>
+            <CheckIcon
+              $active={properties.numFmt === NumberFormats.DATE_LONG}
+            />
+            {t("toolbar.format_menu.date_long")}
+          </MenuItemText>
           <MenuItemExample>
             {t("toolbar.format_menu.date_long_example")}
           </MenuItemExample>
@@ -112,7 +151,10 @@ const FormatMenu = (properties: FormatMenuProps) => {
 
         <MenuDivider />
         <MenuItemWrapper onClick={(): void => setPickerOpen(true)}>
-          <MenuItemText>{t("toolbar.format_menu.custom")}</MenuItemText>
+          <MenuItemText>
+            <CheckIcon $active={isCustomFormat} />
+            {t("toolbar.format_menu.custom")}
+          </MenuItemText>
         </MenuItemWrapper>
       </StyledMenu>
       <FormatPicker
@@ -139,6 +181,7 @@ const StyledMenu = styled(Menu)`
 
 const MenuItemWrapper = styled(MenuItem)`
   display: flex;
+  align-items: center;
   justify-content: space-between;
   font-size: 12px;
   width: calc(100% - 8px);
@@ -161,8 +204,18 @@ const MenuDivider = styled("div")`
   border-top: 1px solid #eeeeee;
 `;
 
+const CheckIcon = styled(Check)<{ $active: boolean }>`
+  width: 16px;
+  height: 16px;
+  color: ${(props) => (props.$active ? "currentColor" : "transparent")};
+  margin-right: 8px;
+  flex-shrink: 0;
+`;
+
 const MenuItemText = styled("div")`
   color: #000;
+  display: flex;
+  align-items: center;
 `;
 
 const MenuItemExample = styled("div")`

webapp/IronCalc/src/components/FormatMenu/formatUtil.ts

@@ -42,3 +42,5 @@ export enum NumberFormats {
   PERCENTAGE = "0.00%",
   NUMBER = "#,##0.00",
 }
+
+export const KNOWN_FORMATS = new Set<string>(Object.values(NumberFormats));

webapp/app.ironcalc.com/Caddyfile.compose

@@ -0,0 +1,17 @@
+:2080 {
+  log {
+    output stdout
+    level INFO
+  }
+
+  @api path /api/*
+  handle @api {
+    reverse_proxy server:8000
+  }
+
+  handle {
+    root * /srv
+    try_files {path} /index.html
+    file_server
+  }
+}

webapp/app.ironcalc.com/frontend/src/App.tsx

@@ -2,6 +2,7 @@ import "./App.css";
 import styled from "@emotion/styled";
 import { useEffect, useState } from "react";
 import { FileBar } from "./components/FileBar";
+import LeftDrawer from "./components/LeftDrawer/LeftDrawer";
 import WelcomeDialog from "./components/WelcomeDialog/WelcomeDialog";
 import {
   get_documentation_model,
@@ -10,6 +11,7 @@ import {
 } from "./components/rpc";
 import {
   createNewModel,
+  deleteModelByUuid,
   deleteSelectedModel,
   isStorageEmpty,
   loadSelectedModelFromStorage,
@@ -27,6 +29,8 @@ function App() {
   const [model, setModel] = useState<Model | null>(null);
   const [showWelcomeDialog, setShowWelcomeDialog] = useState(false);
   const [isTemplatesDialogOpen, setTemplatesDialogOpen] = useState(false);
+  const [isDrawerOpen, setIsDrawerOpen] = useState(false);
+  const [localStorageId, setLocalStorageId] = useState<number>(1);
 
   useEffect(() => {
     async function start() {
@@ -88,11 +92,50 @@ function App() {
     }
   }, 1000);
 
+  // Handlers for model changes that also update our models state
+  const handleNewModel = () => {
+    const newModel = createNewModel();
+    setModel(newModel);
+  };
+
+  const handleSetModel = (uuid: string) => {
+    const newModel = selectModelFromStorage(uuid);
+    if (newModel) {
+      setModel(newModel);
+    }
+  };
+
+  const handleDeleteModel = () => {
+    const newModel = deleteSelectedModel();
+    if (newModel) {
+      setModel(newModel);
+    }
+  };
+
+  const handleDeleteModelByUuid = (uuid: string) => {
+    const newModel = deleteModelByUuid(uuid);
+    if (newModel) {
+      setModel(newModel);
+    }
+  };
+
   // We could use context for model, but the problem is that it should initialized to null.
   // Passing the property down makes sure it is always defined.
 
   return (
     <Wrapper>
+      <LeftDrawer
+        open={isDrawerOpen}
+        onClose={() => setIsDrawerOpen(false)}
+        newModel={handleNewModel}
+        setModel={handleSetModel}
+        onDelete={handleDeleteModelByUuid}
+        localStorageId={localStorageId}
+      />
+      <MainContent isDrawerOpen={isDrawerOpen}>
+        {isDrawerOpen && (
+          <MobileOverlay onClick={() => setIsDrawerOpen(false)} />
+        )}
         <FileBar
           model={model}
           onModelUpload={async (arrayBuffer: ArrayBuffer, fileName: string) => {
@@ -104,27 +147,18 @@ function App() {
 
             setModel(newModel);
           }}
-        newModel={() => {
+          newModel={handleNewModel}
-          const createdModel = createNewModel();
-          setModel(createdModel);
-        }}
           newModelFromTemplate={() => {
             setTemplatesDialogOpen(true);
           }}
-        setModel={(uuid: string) => {
+          setModel={handleSetModel}
-          const newModel = selectModelFromStorage(uuid);
+          onDelete={handleDeleteModel}
-          if (newModel) {
+          isDrawerOpen={isDrawerOpen}
-            setModel(newModel);
+          setIsDrawerOpen={setIsDrawerOpen}
-          }
+          setLocalStorageId={setLocalStorageId}
-        }}
-        onDelete={() => {
-          const newModel = deleteSelectedModel();
-          if (newModel) {
-            setModel(newModel);
-          }
-        }}
         />
         <IronCalc model={model} />
+      </MainContent>
       {showWelcomeDialog && (
         <WelcomeDialog
           onClose={() => {
@@ -175,13 +209,40 @@ function App() {
 }
 
 const Wrapper = styled("div")`
-  margin: 0px;
+  display: flex;
-  padding: 0px;
   width: 100%;
   height: 100%;
+  position: relative;
+  overflow: hidden;
+`;
+
+const DRAWER_WIDTH = 264;
+const MIN_MAIN_CONTENT_WIDTH_FOR_MOBILE = 440;
+
+const MainContent = styled("div")<{ isDrawerOpen: boolean }>`
+  margin-left: ${({ isDrawerOpen }) => (isDrawerOpen ? "0px" : `-${DRAWER_WIDTH}px`)};
+  width: ${({ isDrawerOpen }) => (isDrawerOpen ? `calc(100% - ${DRAWER_WIDTH}px)` : "100%")};
   display: flex;
   flex-direction: column;
+  position: relative;
+  @media (max-width: ${MIN_MAIN_CONTENT_WIDTH_FOR_MOBILE}px) {
+    ${({ isDrawerOpen }) => isDrawerOpen && `min-width: ${MIN_MAIN_CONTENT_WIDTH_FOR_MOBILE}px;`}
+  }
+`;
+
+const MobileOverlay = styled("div")`
   position: absolute;
+  top: 0;
+  left: 0;
+  right: 0;
+  bottom: 0;
+  background-color: rgba(255, 255, 255, 0.8);
+  z-index: 1;
+  cursor: pointer;
+
+  @media (min-width: ${MIN_MAIN_CONTENT_WIDTH_FOR_MOBILE + 1}px) {
+    display: none;
+  }
 `;
 
 const Loading = styled("div")`

webapp/app.ironcalc.com/frontend/src/components/DeleteWorkbookDialog.tsx

@@ -12,19 +12,9 @@ function DeleteWorkbookDialog(properties: DeleteWorkbookDialogProperties) {
   const deleteButtonRef = useRef<HTMLButtonElement>(null);
 
   useEffect(() => {
-    const root = document.getElementById("root");
-    if (root) {
-      root.style.filter = "blur(2px)";
-    }
     if (deleteButtonRef.current) {
       deleteButtonRef.current.focus();
     }
-    return () => {
-      const root = document.getElementById("root");
-      if (root) {
-        root.style.filter = "none";
-      }
-    };
   }, []);
 
   return (

webapp/app.ironcalc.com/frontend/src/components/FileBar.tsx

@@ -1,6 +1,7 @@
 import styled from "@emotion/styled";
 import type { Model } from "@ironcalc/workbook";
-import { IronCalcIcon, IronCalcLogo } from "@ironcalc/workbook";
+import { IconButton, Tooltip } from "@mui/material";
+import { PanelLeftClose, PanelLeftOpen } from "lucide-react";
 import { useLayoutEffect, useRef, useState } from "react";
 import { FileMenu } from "./FileMenu";
 import { HelpMenu } from "./HelpMenu";
@@ -31,6 +32,9 @@ export function FileBar(properties: {
   setModel: (key: string) => void;
   onModelUpload: (blob: ArrayBuffer, fileName: string) => Promise<void>;
   onDelete: () => void;
+  isDrawerOpen: boolean;
+  setIsDrawerOpen: (open: boolean) => void;
+  setLocalStorageId: (updater: (id: number) => number) => void;
 }) {
   const [isDialogOpen, setIsDialogOpen] = useState(false);
   const spacerRef = useRef<HTMLDivElement>(null);
@@ -48,9 +52,29 @@ export function FileBar(properties: {
 
   return (
     <FileBarWrapper>
-      <StyledDesktopLogo />
+      <Tooltip
-      <StyledIronCalcIcon />
+        title="Toggle sidebar"
-      <Divider />
+        slotProps={{
+          popper: {
+            modifiers: [
+              {
+                name: "offset",
+                options: {
+                  offset: [0, -8],
+                },
+              },
+            ],
+          },
+        }}
+      >
+        <DrawerButton
+          onClick={() => properties.setIsDrawerOpen(!properties.isDrawerOpen)}
+          disableRipple
+        >
+          {properties.isDrawerOpen ? <PanelLeftClose /> : <PanelLeftOpen />}
+        </DrawerButton>
+      </Tooltip>
+      {width > 440 && (
         <FileMenu
           newModel={properties.newModel}
           newModelFromTemplate={properties.newModelFromTemplate}
@@ -64,13 +88,15 @@ export function FileBar(properties: {
           }}
           onDelete={properties.onDelete}
         />
-      <HelpMenu />
+      )}
+      {width > 440 && <HelpMenu />}
       <WorkbookTitleWrapper>
         <WorkbookTitle
           name={properties.model.getName()}
           onNameChange={(name) => {
             properties.model.setName(name);
             updateNameSelectedWorkbook(properties.model, name);
+            properties.setLocalStorageId((id) => id + 1);
           }}
           maxWidth={maxTitleWidth}
         />
@@ -103,35 +129,38 @@ const Spacer = styled("div")`
   flex-grow: 1;
 `;
 
-const StyledDesktopLogo = styled(IronCalcLogo)`
+// const DrawerButton = styled(IconButton)<{ $isDrawerOpen: boolean }>`
-  width: 120px;
+// cursor: ${(props) => (props.$isDrawerOpen ? "w-resize" : "e-resize")};
-  margin-left: 12px;
+const DrawerButton = styled(IconButton)`
-  @media (max-width: 769px) {
+  margin-left: 8px;
-    display: none;
+  height: 32px;
-  }
+  width: 32px;
-`;
+  padding: 8px;
+  border-radius: 4px;
 
-const StyledIronCalcIcon = styled(IronCalcIcon)`
+  svg {
-  width: 36px;
+    stroke-width: 2px;
-  margin-left: 10px;
+    stroke: #757575;
-  @media (min-width: 769px) {
+    width: 16px;
-    display: none;
+    height: 16px;
+  }
+  &:hover {
+    background-color: #f2f2f2;
+  }
+  &:active {
+    background-color: #e0e0e0;
   }
-`;
-
-const Divider = styled("div")`
-  margin: 0px 8px 0px 16px;
-  height: 12px;
-  border-left: 1px solid #e0e0e0;
 `;
 
 // The container must be relative positioned so we can position the title absolutely
 const FileBarWrapper = styled("div")`
   position: relative;
   height: 60px;
+  min-height: 60px;
   width: 100%;
   background: #fff;
   display: flex;
+  gap: 2px;
   align-items: center;
   border-bottom: 1px solid #e0e0e0;
   justify-content: space-between;

webapp/app.ironcalc.com/frontend/src/components/FileMenu.tsx

@@ -1,6 +1,6 @@
 import styled from "@emotion/styled";
 import { Menu, MenuItem, Modal } from "@mui/material";
-import { Check, FileDown, FileUp, Plus, Table2, Trash2 } from "lucide-react";
+import { FileDown, FileUp, Plus, Table2, Trash2 } from "lucide-react";
 import { useRef, useState } from "react";
 import DeleteWorkbookDialog from "./DeleteWorkbookDialog";
 import UploadFileDialog from "./UploadFileDialog";
@@ -19,40 +19,8 @@ export function FileMenu(props: {
   const [isImportMenuOpen, setImportMenuOpen] = useState(false);
   const anchorElement = useRef<HTMLButtonElement>(null);
   const models = getModelsMetadata();
-  const uuids = Object.keys(models);
   const selectedUuid = getSelectedUuid();
   const [isDeleteDialogOpen, setDeleteDialogOpen] = useState(false);
-  const elements = [];
-  for (const uuid of uuids) {
-    elements.push(
-      <MenuItemWrapper
-        key={uuid}
-        onClick={() => {
-          props.setModel(uuid);
-          setMenuOpen(false);
-        }}
-      >
-        <CheckIndicator>
-          {uuid === selectedUuid ? (
-            <StyledIcon>
-              <Check />
-            </StyledIcon>
-          ) : (
-            ""
-          )}
-        </CheckIndicator>
-        <MenuItemText
-          style={{
-            maxWidth: "240px",
-            overflow: "hidden",
-            textOverflow: "ellipsis",
-          }}
-        >
-          {models[uuid]}
-        </MenuItemText>
-      </MenuItemWrapper>,
-    );
-  }
 
   return (
     <>
@@ -90,10 +58,8 @@ export function FileMenu(props: {
             setMenuOpen(false);
           }}
         >
-          <StyledIcon>
           <Plus />
-          </StyledIcon>
+          New blank workbook
-          <MenuItemText>New blank workbook</MenuItemText>
         </MenuItemWrapper>
         <MenuItemWrapper
           onClick={() => {
@@ -101,10 +67,8 @@ export function FileMenu(props: {
             setMenuOpen(false);
           }}
         >
-          <StyledIcon>
           <Table2 />
-          </StyledIcon>
+          New from template
-          <MenuItemText>New from template</MenuItemText>
         </MenuItemWrapper>
         <MenuItemWrapper
           onClick={() => {
@@ -112,31 +76,23 @@ export function FileMenu(props: {
             setMenuOpen(false);
           }}
         >
-          <StyledIcon>
           <FileUp />
-          </StyledIcon>
+          Import
-          <MenuItemText>Import</MenuItemText>
         </MenuItemWrapper>
         <MenuDivider />
         <MenuItemWrapper onClick={props.onDownload}>
-          <StyledIcon>
           <FileDown />
-          </StyledIcon>
+          Download (.xlsx)
-          <MenuItemText>Download (.xlsx)</MenuItemText>
         </MenuItemWrapper>
-        <MenuItemWrapper
+        <DeleteButton
           onClick={() => {
             setDeleteDialogOpen(true);
             setMenuOpen(false);
           }}
         >
-          <StyledIcon>
           <Trash2 />
-          </StyledIcon>
+          Delete workbook
-          <MenuItemText>Delete workbook</MenuItemText>
+        </DeleteButton>
-        </MenuItemWrapper>
-        <MenuDivider />
-        {elements}
       </Menu>
       <Modal
         open={isImportMenuOpen}
@@ -162,25 +118,14 @@ export function FileMenu(props: {
         <DeleteWorkbookDialog
           onClose={() => setDeleteDialogOpen(false)}
           onConfirm={props.onDelete}
-          workbookName={selectedUuid ? models[selectedUuid] : ""}
+          workbookName={selectedUuid ? models[selectedUuid].name : ""}
         />
       </Modal>
     </>
   );
 }
 
-const StyledIcon = styled.div`
+export const MenuDivider = styled.div`
-  display: flex;
-  align-items: center;
-  svg {
-    width: 16px;
-    height: 100%;
-    color: #757575;
-    padding-right: 10px;
-  }
-`;
-
-const MenuDivider = styled.div`
   width: 100%;
   margin: auto;
   margin-top: 4px;
@@ -188,12 +133,7 @@ const MenuDivider = styled.div`
   border-top: 1px solid #eeeeee;
 `;
 
-const MenuItemText = styled.div`
+export const MenuItemWrapper = styled(MenuItem)`
-  color: #000;
-  font-size: 12px;
-`;
-
-const MenuItemWrapper = styled(MenuItem)`
   display: flex;
   justify-content: flex-start;
   font-size: 14px;
@@ -203,6 +143,14 @@ const MenuItemWrapper = styled(MenuItem)`
   border-radius: 4px;
   padding: 8px;
   height: 32px;
+  color: #000;
+  font-size: 12px;
+  gap: 8px;
+  svg {
+    width: 16px;
+    height: 100%;
+    color: #757575;
+  }
 `;
 
 const FileMenuWrapper = styled.button<{ $isActive: boolean }>`
@@ -215,14 +163,20 @@ const FileMenuWrapper = styled.button<{ $isActive: boolean }>`
   cursor: pointer;
   background-color: ${(props) => (props.$isActive ? "#e6e6e6" : "transparent")};
   border: none;
-  background: none;
   &:hover {
     background-color: #f2f2f2;
   }
 `;
 
-const CheckIndicator = styled.span`
+export const DeleteButton = styled(MenuItemWrapper)`
-  display: flex;
+  color: #EB5757;
-  justify-content: center;
+  svg {
-  min-width: 26px;
+    color: #EB5757;
+  }
+  &:hover {
+    background-color: #EB57571A;
+  }
+  &:active {
+    background-color: #EB57571A;
+  }
 `;

webapp/app.ironcalc.com/frontend/src/components/HelpMenu.tsx

@@ -1,7 +1,8 @@
 import styled from "@emotion/styled";
-import { Menu, MenuItem } from "@mui/material";
+import { Menu } from "@mui/material";
 import { BookOpen, Keyboard } from "lucide-react";
 import { useRef, useState } from "react";
+import { MenuItemWrapper } from "./FileMenu";
 
 export function HelpMenu() {
   const [isMenuOpen, setMenuOpen] = useState(false);
@@ -61,10 +62,8 @@ export function HelpMenu() {
             );
           }}
         >
-          <StyledIcon>
           <BookOpen />
-          </StyledIcon>
+          Documentation
-          <MenuItemText>Documentation</MenuItemText>
         </MenuItemWrapper>
         <MenuItemWrapper
           onClick={() => {
@@ -76,10 +75,8 @@ export function HelpMenu() {
             );
           }}
         >
-          <StyledIcon>
           <Keyboard />
-          </StyledIcon>
+          Keyboard Shortcuts
-          <MenuItemText>Keyboard Shortcuts</MenuItemText>
         </MenuItemWrapper>
       </Menu>
     </div>
@@ -96,37 +93,7 @@ const HelpButton = styled.button<{ $isActive?: boolean }>`
   cursor: pointer;
   background-color: ${(props) => (props.$isActive ? "#e6e6e6" : "transparent")};
   border: none;
-  background: none;
   &:hover {
     background-color: #f2f2f2;
   }
 `;
-
-const MenuItemWrapper = styled(MenuItem)`
-  display: flex;
-  align-items: center;
-  justify-content: flex-start;
-  font-size: 14px;
-  width: calc(100% - 8px);
-  min-width: 172px;
-  margin: 0px 4px;
-  border-radius: 4px;
-  padding: 8px;
-  height: 32px;
-`;
-
-const StyledIcon = styled.div`
-  display: flex;
-  align-items: center;
-  svg {
-    width: 16px;
-    height: 100%;
-    color: #757575;
-    padding-right: 10px;
-  }
-`;
-
-const MenuItemText = styled.div`
-  color: #000;
-  font-size: 12px;
-`;

webapp/app.ironcalc.com/frontend/src/components/LeftDrawer/DrawerContent.tsx

@@ -0,0 +1,29 @@
+import styled from "@emotion/styled";
+import WorkbookList from "./WorkbookList";
+
+interface DrawerContentProps {
+  setModel: (key: string) => void;
+  onDelete: (uuid: string) => void;
+}
+
+function DrawerContent(props: DrawerContentProps) {
+  const { setModel, onDelete } = props;
+
+  return (
+    <ContentContainer>
+      <WorkbookList setModel={setModel} onDelete={onDelete} />
+    </ContentContainer>
+  );
+}
+
+const ContentContainer = styled("div")`
+  display: flex;
+  flex-direction: column;
+  gap: 4px;
+  padding: 16px 12px;
+  height: 100%;
+  overflow: scroll;
+  font-size: 12px;
+`;
+
+export default DrawerContent;

webapp/app.ironcalc.com/frontend/src/components/LeftDrawer/DrawerFooter.tsx

@@ -0,0 +1,71 @@
+import styled from "@emotion/styled";
+import { BookOpen } from "lucide-react";
+
+function DrawerFooter() {
+  return (
+    <StyledDrawerFooter>
+      <FooterLink
+        href="https://docs.ironcalc.com/"
+        target="_blank"
+        rel="noopener noreferrer"
+      >
+        <OpenBookIcon>
+          <BookOpen />
+        </OpenBookIcon>
+        <FooterLinkText>Documentation</FooterLinkText>
+      </FooterLink>
+    </StyledDrawerFooter>
+  );
+}
+
+const StyledDrawerFooter = styled("div")`
+  display: flex;
+  align-items: center;
+  padding: 12px;
+  justify-content: space-between;
+  max-height: 60px;
+  height: 60px;
+  border-top: 1px solid #e0e0e0;
+  box-sizing: border-box;
+`;
+
+const FooterLink = styled("a")`
+  display: flex;
+  gap: 8px;
+  justify-content: flex-start;
+  font-size: 14px;
+  width: 100%;
+  min-width: 172px;
+  border-radius: 8px;
+  padding: 8px 4px 8px 8px;
+  transition: gap 0.5s;
+  background-color: transparent;
+  color: #000;
+  text-decoration: none;
+  align-items: center;
+
+  &:hover {
+    background-color: #e0e0e0 !important;
+  }
+`;
+
+const OpenBookIcon = styled("div")`
+  height: 16px;
+  width: 16px;
+  svg {
+    height: 16px;
+    width: 16px;
+    stroke: #9e9e9e;
+  }
+`;
+
+const FooterLinkText = styled("div")`
+  color: #000;
+  font-size: 12px;
+  width: 100%;
+  max-width: 240px;
+  overflow: hidden;
+  text-overflow: ellipsis;
+`;
+
+export default DrawerFooter;

webapp/app.ironcalc.com/frontend/src/components/LeftDrawer/DrawerHeader.tsx

@@ -0,0 +1,98 @@
+import styled from "@emotion/styled";
+import { IronCalcIconWhite as IronCalcIcon } from "@ironcalc/workbook";
+import { IconButton, Tooltip } from "@mui/material";
+import { Plus } from "lucide-react";
+import { DialogHeaderLogoWrapper } from "../WelcomeDialog/WelcomeDialog";
+
+interface DrawerHeaderProps {
+  onNewModel: () => void;
+}
+
+function DrawerHeader({ onNewModel }: DrawerHeaderProps) {
+  return (
+    <HeaderContainer>
+      <LogoWrapper>
+        <Logo>
+          <IronCalcIcon />
+        </Logo>
+        <Title>IronCalc</Title>
+      </LogoWrapper>
+      <Tooltip
+        title="New workbook"
+        slotProps={{
+          popper: {
+            modifiers: [
+              {
+                name: "offset",
+                options: {
+                  offset: [0, -8],
+                },
+              },
+            ],
+          },
+        }}
+      >
+        <AddButton onClick={onNewModel}>
+          <PlusIcon />
+        </AddButton>
+      </Tooltip>
+    </HeaderContainer>
+  );
+}
+
+const HeaderContainer = styled("div")`
+  display: flex;
+  align-items: center;
+  padding: 12px 8px 12px 16px;
+  justify-content: space-between;
+  max-height: 60px;
+  min-height: 60px;
+  box-sizing: border-box;
+  box-shadow: 0 1px 0 0 #e0e0e0;
+`;
+
+const LogoWrapper = styled("div")`
+  display: flex;
+  align-items: center;
+  gap: 8px;
+
+`;
+
+const Title = styled("h1")`
+  font-size: 14px;
+  font-weight: 600;
+`;
+
+const Logo = styled(DialogHeaderLogoWrapper)`
+  transform: none;
+  margin-bottom: 0px;
+  padding: 6px;
+`;
+
+const AddButton = styled(IconButton)`
+  margin-left: 8px;
+  height: 32px;
+  width: 32px;
+  padding: 8px;
+  border-radius: 4px;
+
+  svg {
+    stroke-width: 2px;
+    stroke: #757575;
+    width: 16px;
+    height: 16px;
+  }
+  &:hover {
+    background-color: #E0E0E0;
+  }
+  &:active {
+    background-color: #BDBDBD;
+  }
+`;
+
+const PlusIcon = styled(Plus)`
+  width: 16px;
+  height: 16px;
+`;
+
+export default DrawerHeader;

webapp/app.ironcalc.com/frontend/src/components/LeftDrawer/LeftDrawer.tsx

@@ -0,0 +1,53 @@
+import styled from "@emotion/styled";
+import { Drawer } from "@mui/material";
+import DrawerContent from "./DrawerContent";
+import DrawerFooter from "./DrawerFooter";
+import DrawerHeader from "./DrawerHeader";
+
+interface LeftDrawerProps {
+  open: boolean;
+  onClose: () => void;
+  newModel: () => void;
+  setModel: (key: string) => void;
+  onDelete: (uuid: string) => void;
+  localStorageId: number;
+}
+
+function LeftDrawer({
+  open,
+  onClose,
+  newModel,
+  setModel,
+  onDelete,
+}: LeftDrawerProps) {
+  return (
+    <DrawerWrapper
+      variant="persistent"
+      anchor="left"
+      open={open}
+      onClose={onClose}
+      transitionDuration={0}
+    >
+      <DrawerHeader onNewModel={newModel} />
+      <DrawerContent setModel={setModel} onDelete={onDelete} />
+
+      <DrawerFooter />
+    </DrawerWrapper>
+  );
+}
+
+const DrawerWrapper = styled(Drawer)`
+  width: 264px;
+  height: 100%;
+  flex-shrink: 0;
+  font-family: "Inter", sans-serif;
+
+  .MuiDrawer-paper {
+    width: 264px;
+    background-color: #f5f5f5;
+    overflow: hidden;
+    border-right: 1px solid #e0e0e0;
+  }
+`;
+
+export default LeftDrawer;

webapp/app.ironcalc.com/frontend/src/components/LeftDrawer/WorkbookList.tsx

@@ -0,0 +1,426 @@
+import styled from "@emotion/styled";
+import { Menu, MenuItem, Modal } from "@mui/material";
+import {
+  Copy,
+  EllipsisVertical,
+  FileDown,
+  Pin,
+  PinOff,
+  Table2,
+  Trash2,
+} from "lucide-react";
+import type React from "react";
+import { useEffect, useState } from "react";
+import DeleteWorkbookDialog from "../DeleteWorkbookDialog";
+import { DeleteButton, MenuDivider, MenuItemWrapper } from "../FileMenu";
+import { downloadModel } from "../rpc";
+import {
+  duplicateModel,
+  getModelsMetadata,
+  getSelectedUuid,
+  isWorkbookPinned,
+  selectModelFromStorage,
+  togglePinWorkbook,
+} from "../storage";
+
+interface WorkbookListProps {
+  setModel: (key: string) => void;
+  onDelete: (uuid: string) => void;
+}
+
+function WorkbookList({ setModel, onDelete }: WorkbookListProps) {
+  const [menuAnchorEl, setMenuAnchorEl] = useState<null | HTMLElement>(null);
+  const [selectedWorkbookUuid, setSelectedWorkbookUuid] = useState<
+    string | null
+  >(null);
+  const [isDeleteDialogOpen, setIsDeleteDialogOpen] = useState(false);
+  const [workbookToDelete, setWorkbookToDelete] = useState<string | null>(null);
+  const [intendedSelection, setIntendedSelection] = useState<string | null>(
+    null,
+  );
+
+  const selectedUuid = getSelectedUuid();
+
+  // Clear intended selection when selectedUuid changes from outside
+  useEffect(() => {
+    if (intendedSelection && selectedUuid === intendedSelection) {
+      setIntendedSelection(null);
+    }
+  }, [selectedUuid, intendedSelection]);
+
+  const handleMenuOpen = (
+    event: React.MouseEvent<HTMLButtonElement>,
+    uuid: string,
+  ) => {
+    console.log("Menu open", uuid);
+    event.stopPropagation();
+    setSelectedWorkbookUuid(uuid);
+    setMenuAnchorEl(event.currentTarget);
+    setIntendedSelection(uuid);
+    setModel(uuid);
+  };
+
+  const handleMenuClose = () => {
+    console.log(
+      "Menu closing, selectedWorkbookUuid:",
+      selectedWorkbookUuid,
+      "intendedSelection:",
+      intendedSelection,
+    );
+    setMenuAnchorEl(null);
+    // If we have an intended selection, make sure it's still selected
+    if (intendedSelection && intendedSelection !== selectedUuid) {
+      console.log("Re-selecting intended workbook:", intendedSelection);
+      setModel(intendedSelection);
+    }
+    // Don't reset selectedWorkbookUuid here - we want to keep track of which workbook was selected
+    // The selectedWorkbookUuid will be used for download/delete operations
+  };
+
+  const handleDeleteClick = (uuid: string) => {
+    console.log("Delete workbook:", uuid);
+    setWorkbookToDelete(uuid);
+    setIsDeleteDialogOpen(true);
+    setIntendedSelection(null);
+    handleMenuClose();
+  };
+
+  const handleDeleteConfirm = () => {
+    if (workbookToDelete) {
+      onDelete(workbookToDelete);
+      setWorkbookToDelete(null);
+    }
+    setIsDeleteDialogOpen(false);
+  };
+
+  const handleDeleteCancel = () => {
+    setWorkbookToDelete(null);
+    setIsDeleteDialogOpen(false);
+  };
+
+  const handleDownload = async (uuid: string) => {
+    try {
+      const model = selectModelFromStorage(uuid);
+      if (model) {
+        const bytes = model.toBytes();
+        const fileName = model.getName();
+        await downloadModel(bytes, fileName);
+      }
+    } catch (error) {
+      console.error("Failed to download workbook:", error);
+    }
+  };
+
+  const handlePinToggle = (uuid: string) => {
+    togglePinWorkbook(uuid);
+    setIntendedSelection(null);
+    handleMenuClose();
+  };
+
+  const handleDuplicate = (uuid: string) => {
+    const duplicatedModel = duplicateModel(uuid);
+    if (duplicatedModel) {
+      setIntendedSelection(null);
+      handleMenuClose();
+    }
+  };
+
+  // Group workbooks by pinned status and creation date
+  const groupWorkbooks = () => {
+    const now = Date.now();
+    const millisecondsInDay = 24 * 60 * 60 * 1000;
+    const millisecondsIn30Days = 30 * millisecondsInDay;
+
+    const pinnedModels = [];
+    const modelsCreatedToday = [];
+    const modelsCreatedThisMonth = [];
+    const olderModels = [];
+    const modelsMetadata = getModelsMetadata();
+
+    for (const uuid in modelsMetadata) {
+      const createdAt = modelsMetadata[uuid].createdAt;
+      const age = now - createdAt;
+
+      if (modelsMetadata[uuid].pinned) {
+        pinnedModels.push(uuid);
+      } else if (age < millisecondsInDay) {
+        modelsCreatedToday.push(uuid);
+      } else if (age < millisecondsIn30Days) {
+        modelsCreatedThisMonth.push(uuid);
+      } else {
+        olderModels.push(uuid);
+      }
+    }
+
+    // Sort each group by creation timestamp (newest first)
+    const sortByNewest = (uuids: string[]) =>
+      uuids.sort(
+        (a, b) => modelsMetadata[b].createdAt - modelsMetadata[a].createdAt,
+      );
+
+    return {
+      pinnedModels: sortByNewest(pinnedModels),
+      modelsCreatedToday: sortByNewest(modelsCreatedToday),
+      modelsCreatedThisMonth: sortByNewest(modelsCreatedThisMonth),
+      olderModels: sortByNewest(olderModels),
+    };
+  };
+
+  const {
+    pinnedModels,
+    modelsCreatedToday,
+    modelsCreatedThisMonth,
+    olderModels,
+  } = groupWorkbooks();
+
+  const renderWorkbookItem = (uuid: string) => {
+    const isMenuOpen = menuAnchorEl !== null && selectedWorkbookUuid === uuid;
+    const isAnyMenuOpen = menuAnchorEl !== null;
+    const models = getModelsMetadata();
+    return (
+      <WorkbookListItem
+        key={uuid}
+        onClick={() => {
+          // Prevent clicking on list items when any menu is open
+          if (isAnyMenuOpen) {
+            return;
+          }
+          setModel(uuid);
+        }}
+        selected={uuid === selectedUuid}
+        disableRipple
+        style={{ pointerEvents: isAnyMenuOpen ? "none" : "auto" }}
+      >
+        <StorageIndicator>
+          <Table2 />
+        </StorageIndicator>
+        <WorkbookListText>{models[uuid].name}</WorkbookListText>
+        <EllipsisButton
+          onClick={(e) => handleMenuOpen(e, uuid)}
+          isOpen={isMenuOpen}
+          onMouseDown={(e) => e.stopPropagation()}
+          style={{ pointerEvents: "auto" }}
+        >
+          <EllipsisVertical />
+        </EllipsisButton>
+      </WorkbookListItem>
+    );
+  };
+
+  const renderSection = (title: string, uuids: string[]) => {
+    if (uuids.length === 0) return null;
+
+    return (
+      <SectionContainer key={title}>
+        <SectionTitle>
+          {title === "Pinned" && <Pin />}
+          {title}
+        </SectionTitle>
+        {uuids.map(renderWorkbookItem)}
+      </SectionContainer>
+    );
+  };
+
+  const models = getModelsMetadata();
+
+  return (
+    <>
+      {renderSection("Pinned", pinnedModels)}
+      {renderSection("Today", modelsCreatedToday)}
+      {renderSection("Last 30 Days", modelsCreatedThisMonth)}
+      {renderSection("Older", olderModels)}
+
+      <StyledMenu
+        anchorEl={menuAnchorEl}
+        open={Boolean(menuAnchorEl)}
+        onClose={handleMenuClose}
+        MenuListProps={{
+          dense: true,
+        }}
+        anchorOrigin={{
+          vertical: "bottom",
+          horizontal: "right",
+        }}
+        transformOrigin={{
+          vertical: "top",
+          horizontal: "right",
+        }}
+      >
+        <MenuItemWrapper
+          onClick={() => {
+            console.log(
+              "Download clicked, selectedWorkbookUuid:",
+              selectedWorkbookUuid,
+            );
+            if (selectedWorkbookUuid) {
+              handleDownload(selectedWorkbookUuid);
+            }
+            setIntendedSelection(null);
+            handleMenuClose();
+          }}
+          disableRipple
+        >
+          <FileDown />
+          Download (.xlsx)
+        </MenuItemWrapper>
+        <MenuItemWrapper
+          onClick={() => {
+            if (selectedWorkbookUuid) {
+              handlePinToggle(selectedWorkbookUuid);
+            }
+          }}
+          disableRipple
+        >
+          {selectedWorkbookUuid && isWorkbookPinned(selectedWorkbookUuid) ? (
+            <PinOff />
+          ) : (
+            <Pin />
+          )}
+          {selectedWorkbookUuid && isWorkbookPinned(selectedWorkbookUuid)
+            ? "Unpin"
+            : "Pin"}
+        </MenuItemWrapper>
+        <MenuItemWrapper
+          onClick={() => {
+            if (selectedWorkbookUuid) {
+              handleDuplicate(selectedWorkbookUuid);
+            }
+          }}
+          disableRipple
+        >
+          <Copy />
+          Duplicate
+        </MenuItemWrapper>
+        <MenuDivider />
+        <DeleteButton
+          selected={false}
+          onClick={() => {
+            if (selectedWorkbookUuid) {
+              handleDeleteClick(selectedWorkbookUuid);
+            }
+          }}
+          disableRipple
+        >
+          <Trash2 size={16} />
+          Delete workbook
+        </DeleteButton>
+      </StyledMenu>
+
+      <Modal
+        open={isDeleteDialogOpen}
+        onClose={handleDeleteCancel}
+        aria-labelledby="delete-dialog-title"
+        aria-describedby="delete-dialog-description"
+      >
+        <DeleteWorkbookDialog
+          onClose={handleDeleteCancel}
+          onConfirm={handleDeleteConfirm}
+          workbookName={workbookToDelete ? models[workbookToDelete].name : ""}
+        />
+      </Modal>
+    </>
+  );
+}
+
+const StorageIndicator = styled("div")`
+  height: 16px;
+  width: 16px;
+  svg {
+    height: 16px;
+    width: 16px;
+    stroke: #9e9e9e;
+  }
+`;
+
+const EllipsisButton = styled("button")<{ isOpen: boolean }>`
+  background: none;
+  border: none;
+  cursor: pointer;
+  display: flex;
+  align-items: center;
+  justify-content: center;
+  padding: 4px;
+  height: 24px;
+  width: ${({ isOpen }) => (isOpen ? "24px" : "0px")};
+  border-radius: 4px;
+  color: #333333;
+  stroke-width: 2px;
+  background-color: ${({ isOpen }) => (isOpen ? "#E0E0E0" : "none")};
+  opacity: ${({ isOpen }) => (isOpen ? "1" : "0")};
+  &:hover {
+    background: #BDBDBD;
+    opacity: 1;
+  }
+  &:active {
+    background: #bdbdbd;
+    opacity: 1;
+  }
+`;
+
+const WorkbookListItem = styled(MenuItem)<{ selected: boolean }>`
+  display: flex;
+  gap: 8px;
+  justify-content: flex-start;
+  font-size: 14px;
+  width: 100%;
+  min-width: 172px;
+  border-radius: 8px;
+  padding: 8px 4px 8px 8px;
+  height: 32px;
+  min-height: 32px;
+  transition: gap 0.5s;
+  background-color: ${({ selected }) =>
+    selected ? "#e0e0e0 !important" : "transparent"};
+
+  &:hover {
+    background-color: #e0e0e0;
+    button {
+      opacity: 1;
+      min-width: 24px;
+    }
+  }
+`;
+
+const WorkbookListText = styled("div")`
+  color: #000;
+  font-size: 12px;
+  width: 100%;
+  max-width: 240px;
+  overflow: hidden;
+  text-overflow: ellipsis;
+`;
+
+const StyledMenu = styled(Menu)`
+  .MuiPaper-root {
+    border-radius: 8px;
+    padding: 4px 0px;
+    box-shadow: 0px 2px 4px rgba(0, 0, 0, 0.01);
+  },
+  .MuiList-root {
+    padding: 0;
+  },
+`;
+
+const SectionContainer = styled("div")`
+  margin-bottom: 16px;
+  display: flex;
+  flex-direction: column;
+  gap: 2px;
+`;
+
+const SectionTitle = styled("div")`
+  display: flex;
+  align-items: center;
+  gap: 4px;
+  font-weight: 400;
+  color: #9e9e9e;
+  margin-bottom: 8px;
+  padding: 0px 8px;
+  font-size: 12px;
+  svg {
+    width: 12px;
+    height: 12px;
+  }
+`;
+
+export default WorkbookList;

webapp/app.ironcalc.com/frontend/src/components/ShareButton.tsx

@@ -5,8 +5,8 @@ export function ShareButton(properties: { onClick: () => void }) {
   const { onClick } = properties;
   return (
     <Wrapper onClick={onClick} onKeyDown={() => {}}>
-      <Share2 style={{ width: "16px", height: "16px", marginRight: "10px" }} />
+      <ShareIcon />
-      <span>Share</span>
+      <ShareText>Share</ShareText>
     </Wrapper>
   );
 }
@@ -23,8 +23,24 @@ const Wrapper = styled("div")`
   display: flex;
   align-items: center;
   font-family: "Inter";
-  font-size: 14px;
+  font-size: 12px;
   &:hover {
     background: #d68742;
   }
 `;
+
+const ShareIcon = styled(Share2)`
+  width: 16px;
+  height: 16px;
+  margin-right: 10px;
+  
+  @media (max-width: 440px) {
+    margin-right: 0px;
+  }
+`;
+
+const ShareText = styled.span`
+  @media (max-width: 440px) {
+    display: none;
+  }
+`;

webapp/app.ironcalc.com/frontend/src/components/WelcomeDialog/WelcomeDialog.tsx

@@ -106,7 +106,7 @@ const DialogHeaderTitleSubtitle = styled("span")`
   color: #757575;
 `;
 
-const DialogHeaderLogoWrapper = styled("div")`
+export const DialogHeaderLogoWrapper = styled("div")`
   display: flex;
   flex-direction: row;
   align-items: center;

webapp/app.ironcalc.com/frontend/src/components/WorkbookTitle.tsx

@@ -72,10 +72,10 @@ export function WorkbookTitle(properties: {
 }
 
 const Container = styled("div")`
-  text-align: center;
+  text-align: left;
-  padding: 8px;
+  padding: 6px 4px;
   font-size: 14px;
-  font-weight: 700;
+  font-weight: 600;
   font-family: Inter;
 `;
 
@@ -108,7 +108,7 @@ const TitleInput = styled("input")`
     background-color: #f2f2f2;
   }
   &:focus {
-    border: 1px solid grey;
+    outline: 1px solid grey;
   }
   font-weight: inherit;
   font-family: inherit;

webapp/app.ironcalc.com/frontend/src/components/storage.ts

@@ -3,7 +3,10 @@ import { base64ToBytes, bytesToBase64 } from "./util";
 
 const MAX_WORKBOOKS = 50;
 
-type ModelsMetadata = Record<string, string>;
+type ModelsMetadata = Record<
+  string,
+  { name: string; createdAt: number; pinned?: boolean }
+>;
 
 export function updateNameSelectedWorkbook(model: Model, newName: string) {
   const uuid = localStorage.getItem("selected");
@@ -12,7 +15,11 @@ export function updateNameSelectedWorkbook(model: Model, newName: string) {
     if (modelsJson) {
       try {
         const models = JSON.parse(modelsJson);
-        models[uuid] = newName;
+        if (models[uuid]) {
+          models[uuid].name = newName;
+        } else {
+          models[uuid] = { name: newName, createdAt: Date.now() };
+        }
         localStorage.setItem("models", JSON.stringify(models));
       } catch (e) {
         console.warn("Failed saving new name");
@@ -28,7 +35,26 @@ export function getModelsMetadata(): ModelsMetadata {
   if (!modelsJson) {
     modelsJson = "{}";
   }
-  return JSON.parse(modelsJson);
+  const models = JSON.parse(modelsJson);
+
+  // Migrate old format to new format
+  const migratedModels: ModelsMetadata = {};
+  for (const [uuid, value] of Object.entries(models)) {
+    if (typeof value === "string") {
+      // Old format: just the name string
+      migratedModels[uuid] = { name: value, createdAt: Date.now() };
+    } else if (typeof value === "object" && value !== null && "name" in value) {
+      // New format: object with name and createdAt
+      migratedModels[uuid] = value as { name: string; createdAt: number };
+    }
+  }
+
+  // Save migrated data back to localStorage
+  if (JSON.stringify(models) !== JSON.stringify(migratedModels)) {
+    localStorage.setItem("models", JSON.stringify(migratedModels));
+  }
+
+  return migratedModels;
 }
 
 // Pick a different name Workbook{N} where N = 1, 2, 3
@@ -48,14 +74,14 @@ function getNewName(existingNames: string[]): string {
 
 export function createNewModel(): Model {
   const models = getModelsMetadata();
-  const name = getNewName(Object.values(models));
+  const name = getNewName(Object.values(models).map((m) => m.name));
 
   const model = new Model(name, "en", "UTC");
   const uuid = crypto.randomUUID();
   localStorage.setItem("selected", uuid);
   localStorage.setItem(uuid, bytesToBase64(model.toBytes()));
 
-  models[uuid] = name;
+  models[uuid] = { name, createdAt: Date.now() };
   localStorage.setItem("models", JSON.stringify(models));
   return model;
 }
@@ -103,7 +129,7 @@ export function saveModelToStorage(model: Model) {
     modelsJson = "{}";
   }
   const models = JSON.parse(modelsJson);
-  models[uuid] = model.getName();
+  models[uuid] = { name: model.getName(), createdAt: Date.now() };
   localStorage.setItem("models", JSON.stringify(models));
 }
 
@@ -135,3 +161,79 @@ export function deleteSelectedModel(): Model | null {
   }
   return selectModelFromStorage(uuids[0]);
 }
+
+export function deleteModelByUuid(uuid: string): Model | null {
+  localStorage.removeItem(uuid);
+  const metadata = getModelsMetadata();
+  delete metadata[uuid];
+  localStorage.setItem("models", JSON.stringify(metadata));
+
+  // If this was the selected model, we need to select a different one
+  const selectedUuid = localStorage.getItem("selected");
+  if (selectedUuid === uuid) {
+    const uuids = Object.keys(metadata);
+    if (uuids.length === 0) {
+      return createNewModel();
+    }
+    // Find the newest workbook by creation timestamp
+    const newestUuid = uuids.reduce((newest, current) => {
+      const newestTime = metadata[newest]?.createdAt || 0;
+      const currentTime = metadata[current]?.createdAt || 0;
+      return currentTime > newestTime ? current : newest;
+    });
+    return selectModelFromStorage(newestUuid);
+  }
+
+  // If it wasn't the selected model, return the currently selected model
+  if (selectedUuid) {
+    const modelBytesString = localStorage.getItem(selectedUuid);
+    if (modelBytesString) {
+      return Model.from_bytes(base64ToBytes(modelBytesString));
+    }
+  }
+
+  // Fallback to creating a new model if no valid selected model
+  return createNewModel();
+}
+
+export function togglePinWorkbook(uuid: string): void {
+  const metadata = getModelsMetadata();
+  if (metadata[uuid]) {
+    metadata[uuid].pinned = !metadata[uuid].pinned;
+    localStorage.setItem("models", JSON.stringify(metadata));
+  }
+}
+
+export function isWorkbookPinned(uuid: string): boolean {
+  const metadata = getModelsMetadata();
+  return metadata[uuid]?.pinned || false;
+}
+
+export function duplicateModel(uuid: string): Model | null {
+  const originalModel = selectModelFromStorage(uuid);
+  if (!originalModel) return null;
+
+  const duplicatedModel = Model.from_bytes(originalModel.toBytes());
+  const models = getModelsMetadata();
+  const originalName = models[uuid]?.name || "Workbook";
+  const existingNames = Object.values(models).map((m) => m.name);
+
+  // Find next available number
+  let counter = 1;
+  let newName = `${originalName} (${counter})`;
+  while (existingNames.includes(newName)) {
+    counter++;
+    newName = `${originalName} (${counter})`;
+  }
+
+  duplicatedModel.setName(newName);
+
+  const newUuid = crypto.randomUUID();
+  localStorage.setItem("selected", newUuid);
+  localStorage.setItem(newUuid, bytesToBase64(duplicatedModel.toBytes()));
+
+  models[newUuid] = { name: newName, createdAt: Date.now() };
+  localStorage.setItem("models", JSON.stringify(models));
+
+  return duplicatedModel;
+}

xlsx/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "ironcalc"
-version = "0.5.0"
+version = "0.6.0"
 authors = ["Nicolás Hatcher <nicolas@theuniverse.today>"]
 edition = "2021"
 homepage = "https://www.ironcalc.com"
@@ -20,7 +20,7 @@ thiserror = "1.0"
 # Uses `../base` when used locally, and uses
 # the inicated version from crates.io when published.
 # https://doc.rust-lang.org/cargo/reference/specifying-dependencies.html#multiple-locations
-ironcalc_base = { path = "../base", version = "0.5" }
+ironcalc_base = { path = "../base", version = "0.6" }
 itertools = "0.12"
 chrono = "0.4"
 bitcode = "0.6.0"