UPDATE: Dump of initial files

base/src/workbook.rs

@@ -0,0 +1,30 @@
+use std::vec::Vec;
+
+use crate::types::*;
+
+impl Workbook {
+    pub fn get_worksheet_names(&self) -> Vec<String> {
+        self.worksheets
+            .iter()
+            .map(|worksheet| worksheet.get_name())
+            .collect()
+    }
+    pub fn get_worksheet_ids(&self) -> Vec<u32> {
+        self.worksheets
+            .iter()
+            .map(|worksheet| worksheet.get_sheet_id())
+            .collect()
+    }
+
+    pub fn worksheet(&self, worksheet_index: u32) -> Result<&Worksheet, String> {
+        self.worksheets
+            .get(worksheet_index as usize)
+            .ok_or_else(|| "Invalid sheet index".to_string())
+    }
+
+    pub fn worksheet_mut(&mut self, worksheet_index: u32) -> Result<&mut Worksheet, String> {
+        self.worksheets
+            .get_mut(worksheet_index as usize)
+            .ok_or_else(|| "Invalid sheet index".to_string())
+    }
+}