Change --no-color argument into --color always|ansi|never (#491)

* Change `--no-color` argument into `--color always|ansi|never`

When `ansi` is chosen, this calculates the closes distance between the
RGB color and one of the 8 basic ANSI colors, with the assumption that

* black = `#000000`
* red = `#FF0000`
* etc.

Cargo.toml

@@ -9,7 +9,7 @@ serde_json = "1"
 
 [workspace.package]
 description = "Get the language distribution stats of your repository"
-version = "0.11.5"
+version = "0.12.0"
 edition = "2021"
 repository = "https://github.com/spenserblack/gengo"
 readme = "README.md"

gengo-bin/Cargo.toml

@@ -22,7 +22,7 @@ color = ["gengo/owo-colors", "owo-colors"]
 
 [dependencies]
 clap = { version = "4", features = ["derive", "wrap_help"] }
-gengo = { path = "../gengo", version = "0.11", default-features = false }
+gengo = { path = "../gengo", version = "0.12", default-features = false }
 indexmap.workspace = true
 owo-colors = { workspace = true, optional = true }
 serde_json.workspace = true

gengo-bin/src/cli.rs

@@ -39,10 +39,10 @@ pub struct CLI {
     /// formats always include detailed statistics.
     #[arg(short = 'b', long)]
     breakdown: bool,
-    /// Force the output to not have colors.
+    /// Control when colors are displayed.
     #[cfg(feature = "color")]
-    #[arg(long)]
-    no_color: bool,
+    #[arg(long, default_value = "always")]
+    color: ColorControl,
     /// The format to use for output.
     #[arg(short = 'F', long, default_value = "pretty")]
     format: Format,
@@ -67,6 +67,17 @@ enum Commands {
     },
 }
 
+#[cfg(feature = "color")]
+#[derive(ValueEnum, Debug, Clone)]
+enum ColorControl {
+    /// Always use colors.
+    Always,
+    /// Use only the 8 ANSI colors.
+    Ansi,
+    /// Disable colors.
+    Never,
+}
+
 #[derive(ValueEnum, Debug, Clone)]
 enum Format {
     /// Output for humans.
@@ -194,28 +205,63 @@ impl CLI {
 
     #[cfg(feature = "color")]
     fn colorize(&self, s: &str, color: owo_colors::Rgb) -> String {
-        use owo_colors::{OwoColorize, Rgb};
+        use owo_colors::{AnsiColors::*, OwoColorize, Rgb};
+        use ColorControl::*;
 
-        if self.no_color {
-            return String::from(s);
+        match self.color {
+            Never => String::from(s),
+            Always => {
+                let fg = if Self::is_bright(color.0, color.1, color.2) {
+                    Rgb(0, 0, 0)
+                } else {
+                    Rgb(0xFF, 0xFF, 0xFF)
+                };
+                s.on_color(color).color(fg).to_string()
+            }
+            Ansi => {
+                let (bg, (r, g, b)) = Self::closest_color(color);
+                let fg = if Self::is_bright(r, g, b) {
+                    Black
+                } else {
+                    White
+                };
+                s.on_color(bg).color(fg).to_string()
+            }
         }
+    }
 
+    #[cfg(feature = "color")]
+    fn is_bright(r: u8, g: u8, b: u8) -> bool {
         // NOTE Adapted from https://css-tricks.com/converting-color-spaces-in-javascript/#aa-rgb-to-hsl
-        let r = color.0;
-        let g = color.1;
-        let b = color.2;
         let min: u16 = [r, g, b].into_iter().min().unwrap().into();
         let max: u16 = [r, g, b].into_iter().max().unwrap().into();
         let lightness = (max + min) / 2;
-        let bright = lightness > 0x7F;
+        lightness > 0x7F
+    }
 
-        let line = s.on_color(color);
-        let fg = if bright {
-            Rgb(0, 0, 0)
-        } else {
-            Rgb(0xFF, 0xFF, 0xFF)
-        };
-        line.color(fg).to_string()
+    #[cfg(feature = "color")]
+    fn closest_color(rgb: owo_colors::Rgb) -> (owo_colors::AnsiColors, (u8, u8, u8)) {
+        use owo_colors::AnsiColors::*;
+        // NOTE Gets the closest color by Euclidean distance
+        [
+            (Black, (0u8, 0u8, 0u8)),
+            (Red, (0xFF, 0, 0)),
+            (Yellow, (0xFF, 0xFF, 0)),
+            (Blue, (0, 0, 0xFF)),
+            (Magenta, (0xFF, 0, 0xFF)),
+            (Cyan, (0, 0xFF, 0xFF)),
+            (White, (0xFF, 0xFF, 0xFF)),
+        ]
+        .into_iter()
+        .min_by_key(|(_, (r, g, b))| {
+            // NOTE As a shortcut we'll just skip the square root step
+            [(r, rgb.0), (g, rgb.1), (b, rgb.2)]
+                .into_iter()
+                .map(|(p1, p2)| u32::from(p1.abs_diff(p2)))
+                .map(|diff| diff * diff)
+                .sum::<u32>()
+        })
+        .unwrap()
     }
 
     #[cfg(not(feature = "color"))]

gengo-bin/tests/snapshots/test_cli__color_breakdown_javascript_repo.snap

@@ -14,5 +14,3 @@ expression: stdout
 
 TypeScript
   src/bin.ts
-
-

gengo-bin/tests/snapshots/test_cli__color_javascript_repo.snap

@@ -5,4 +5,3 @@ expression: stdout
  40.79% 62      Plain Text
  40.79% 62      TypeScript
  18.42% 28      JavaScript
-

samples-test/Cargo.toml

@@ -10,4 +10,4 @@ license.workspace = true
 keywords.workspace = true
 
 [dependencies]
-gengo = { path = "../gengo", version = "0.11", default-features = false }
+gengo = { path = "../gengo", version = "0.12", default-features = false }