138 lines
4.1 KiB
Rust
138 lines
4.1 KiB
Rust
use crate::types::BorderItem;
|
|
|
|
fn parse_color(s: &str) -> Option<(u8, u8, u8)> {
|
|
let s = s.trim_start_matches('#');
|
|
match s.len() {
|
|
6 => {
|
|
let r = u8::from_str_radix(&s[0..2], 16).ok()?;
|
|
let g = u8::from_str_radix(&s[2..4], 16).ok()?;
|
|
let b = u8::from_str_radix(&s[4..6], 16).ok()?;
|
|
Some((r, g, b))
|
|
}
|
|
3 => {
|
|
let r = u8::from_str_radix(&s[0..1], 16).ok()?;
|
|
let g = u8::from_str_radix(&s[1..2], 16).ok()?;
|
|
let b = u8::from_str_radix(&s[2..3], 16).ok()?;
|
|
// Expand single hex digits to full bytes
|
|
Some((r * 17, g * 17, b * 17))
|
|
}
|
|
_ => None,
|
|
}
|
|
}
|
|
|
|
fn compute_luminance(r: u8, g: u8, b: u8) -> f64 {
|
|
// Normalize RGB values to [0, 1]
|
|
let r = r as f64 / 255.0;
|
|
let g = g as f64 / 255.0;
|
|
let b = b as f64 / 255.0;
|
|
// Calculate luminance using the Rec. 601 formula
|
|
0.299 * r + 0.587 * g + 0.114 * b
|
|
}
|
|
|
|
fn is_max_color(a: &str, b: &str) -> bool {
|
|
let (ar, ag, ab) = match parse_color(a) {
|
|
Some(rgb) => rgb,
|
|
None => return false, // Invalid color format for 'a'
|
|
};
|
|
|
|
let (br, bg, bb) = match parse_color(b) {
|
|
Some(rgb) => rgb,
|
|
None => return false, // Invalid color format for 'b'
|
|
};
|
|
|
|
let luminance_a = compute_luminance(ar, ag, ab);
|
|
let luminance_b = compute_luminance(br, bg, bb);
|
|
|
|
// 'b' is heavier if its luminance is less than 'a's luminance
|
|
luminance_b < luminance_a
|
|
}
|
|
|
|
/// Is border b "heavier" than a?
|
|
pub(crate) fn is_max_border(a: Option<&BorderItem>, b: Option<&BorderItem>) -> bool {
|
|
match (a, b) {
|
|
(_, None) => false,
|
|
(None, Some(_)) => true,
|
|
(Some(item_a), Some(item_b)) => {
|
|
if item_a.style < item_b.style {
|
|
return true;
|
|
} else if item_a.style > item_b.style {
|
|
return false;
|
|
}
|
|
match (&item_a.color, &item_b.color) {
|
|
(_, None) => false,
|
|
(None, Some(_)) => true,
|
|
(Some(color_a), Some(color_b)) => is_max_color(color_a, color_b),
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
#[cfg(test)]
|
|
mod tests {
|
|
use super::*;
|
|
use crate::types::BorderStyle;
|
|
|
|
#[test]
|
|
fn compare_borders() {
|
|
let b = BorderItem {
|
|
style: BorderStyle::Thin,
|
|
color: Some("#FFF".to_string()),
|
|
};
|
|
// Some border *always* beats no border
|
|
assert!(is_max_border(None, Some(&b)));
|
|
|
|
// No border is beaten by some border
|
|
assert!(!is_max_border(Some(&b), None));
|
|
}
|
|
|
|
#[test]
|
|
fn basic_colors() {
|
|
// Black vs White
|
|
assert!(is_max_color("#FFFFFF", "#000000"));
|
|
assert!(!is_max_color("#000000", "#FFFFFF"));
|
|
|
|
// Red vs Dark Red
|
|
assert!(is_max_color("#FF0000", "#800000"));
|
|
assert!(!is_max_color("#800000", "#FF0000"));
|
|
|
|
// Green vs Dark Green
|
|
assert!(is_max_color("#00FF00", "#008000"));
|
|
assert!(!is_max_color("#008000", "#00FF00"));
|
|
|
|
// Blue vs Dark Blue
|
|
assert!(is_max_color("#0000FF", "#000080"));
|
|
assert!(!is_max_color("#000080", "#0000FF"));
|
|
}
|
|
|
|
#[test]
|
|
fn same_color() {
|
|
// Comparing the same color should return false
|
|
assert!(!is_max_color("#123456", "#123456"));
|
|
}
|
|
|
|
#[test]
|
|
fn edge_cases() {
|
|
// Colors with minimal luminance difference
|
|
assert!(!is_max_color("#000000", "#010101"));
|
|
assert!(!is_max_color("#FEFEFE", "#FFFFFF"));
|
|
assert!(!is_max_color("#7F7F7F", "#808080"));
|
|
}
|
|
|
|
#[test]
|
|
fn luminance_ordering() {
|
|
// Colors with known luminance differences
|
|
assert!(is_max_color("#CCCCCC", "#333333")); // Light gray vs Day
|
|
assert!(is_max_color("#FFFF00", "#808000")); // Yellow ve
|
|
assert!(is_max_color("#FF00FF", "#800080")); // Magenta vle
|
|
}
|
|
|
|
#[test]
|
|
fn borderline_cases() {
|
|
// Testing colors with equal luminance
|
|
assert!(!is_max_color("#777777", "#777777"));
|
|
|
|
// Testing black against near-black
|
|
assert!(!is_max_color("#000000", "#010000"));
|
|
}
|
|
}
|