feat: add color class

packages/shared/src/color.js

@@ -0,0 +1,85 @@
+const FACTOR = 0.7;
+
+export class Color {
+  #value;
+
+  constructor(red, green, blue) {
+    if (green === undefined && blue === undefined) {
+      if (typeof red === 'string') {
+        this.#value = parseInt(red, 16);
+        return;
+      }
+
+      this.#value = Number(red);
+      return;
+    }
+
+    this.#value =
+      ((red & 0xff) << 16) | ((green & 0xff) << 8) | ((blue & 0xff) << 0);
+  }
+
+  get rgb() {
+    return this.#value;
+  }
+
+  get red() {
+    return (this.rgb >> 16) & 0xff;
+  }
+
+  get green() {
+    return (this.rgb >> 8) & 0xff;
+  }
+
+  get blue() {
+    return (this.rgb >> 0) & 0xff;
+  }
+
+  brighter(factor = FACTOR) {
+    if (Number.isNaN(this.rgb)) {
+      return new Color();
+    }
+
+    let red = this.red;
+    let green = this.green;
+    let blue = this.blue;
+
+    const inverse = Math.floor(1 / (1 - factor));
+    if (red === 0 && green === 0 && blue === 0) {
+      return new Color(inverse, inverse, inverse);
+    }
+
+    if (red > 0 && red < inverse) red = inverse;
+    if (green > 0 && green < inverse) green = inverse;
+    if (blue > 0 && blue < inverse) blue = inverse;
+
+    return new Color(
+      Math.min(Math.floor(red / FACTOR), 255),
+      Math.min(Math.floor(green / FACTOR), 255),
+      Math.min(Math.floor(blue / FACTOR), 255),
+    );
+  }
+
+  darker(factor = FACTOR) {
+    if (Number.isNaN(this.rgb)) {
+      return new Color();
+    }
+
+    return new Color(
+      Math.max(Math.floor(this.red * factor), 0),
+      Math.max(Math.floor(this.green * factor), 0),
+      Math.max(Math.floor(this.blue * factor), 0),
+    );
+  }
+
+  valueOf() {
+    return this.rgb;
+  }
+
+  toString() {
+    if (Number.isNaN(this.rgb)) {
+      return 'Invalid Color';
+    }
+
+    return this.rgb.toString(16).padStart(6, '0');
+  }
+}

packages/shared/src/index.js

@@ -1,4 +1,5 @@
 export * from './clock.js';
+export * from './color.js';
 export * from './configurable-responses.js';
 export * from './duration.js';
 export * from './logging.js';

packages/shared/test/color.test.js

@@ -0,0 +1,59 @@
+import { describe, expect, test } from '@jest/globals';
+
+import { Color } from '../src';
+
+describe('Color', () => {
+  test('Creates a color instance from RGB values', () => {
+    const color = new Color(14, 83, 255);
+
+    expect(color.rgb).toEqual(0x0e53ff);
+    expect(color.red).toEqual(14);
+    expect(color.green).toEqual(83);
+    expect(color.blue).toEqual(255);
+    expect(color.valueOf()).toEqual(0x0e53ff);
+    expect(color.toString()).toEqual('0e53ff');
+  });
+
+  test('Creates a color instance from RGB value', () => {
+    const color = new Color(0x0e53ff);
+
+    expect(color.valueOf()).toEqual(0x0e53ff);
+  });
+
+  test('Creates a color instance from RGB string', () => {
+    const color = new Color('0e53ff');
+
+    expect(color.valueOf()).toEqual(0x0e53ff);
+  });
+
+  test('Creates invalid color', () => {
+    const color = new Color();
+
+    expect(color.valueOf()).toEqual(Number.NaN);
+    expect(color.toString()).toEqual('Invalid Color');
+  });
+
+  test('Returns darker color', () => {
+    const color = new Color('0e53ff');
+
+    const newColor = color.darker();
+
+    expect(newColor.toString()).toEqual('093ab2');
+  });
+
+  test('Returns brighter color', () => {
+    const color = new Color('093ab2');
+
+    const newColor = color.brighter();
+
+    expect(newColor.toString()).toEqual('0c52fe');
+  });
+
+  test('Returns grey when color is black', () => {
+    const color = new Color('000000');
+
+    const newColor = color.brighter();
+
+    expect(newColor.toString()).toEqual('030303');
+  });
+});