change getContrastColor -> invertColor while improving implementation…

… and writing new tests

site/docs/api-reference/invertColor.md

@@ -0,0 +1,7 @@
+---
+sidebar_position: 2
+tags:
+  - validation
+---
+
+# invertColor

site/docs/api-reference/isEmpty.md

@@ -1,5 +1,5 @@
 ---
-sidebar_position: 2
+sidebar_position: 3
 tags:
   - validation
 ---

site/docs/api-reference/isNil.md

@@ -1,5 +1,5 @@
 ---
-sidebar_position: 3
+sidebar_position: 4
 tags:
   - validation
 ---

site/docs/api-reference/omit.md

@@ -1,5 +1,5 @@
 ---
-sidebar_position: 4
+sidebar_position: 5
 tags:
   - object
 ---

site/docs/api-reference/pick.md

@@ -1,5 +1,5 @@
 ---
-sidebar_position: 5
+sidebar_position: 6
 tags:
   - object
 ---

site/docs/api-reference/uniq.md

@@ -1,5 +1,5 @@
 ---
-sidebar_position: 6
+sidebar_position: 7
 tags:
   - array
 ---

src/invertColor/index.ts

@@ -0,0 +1 @@
+export * from './invertColor';

src/invertColor/invertColor.test.ts

@@ -0,0 +1,39 @@
+import { describe, it, expect } from 'vitest';
+import { invertColor } from './invertColor';
+
+describe('invertColor()', () => {
+  describe('when the color is provided as a string', () => {
+    it('should invert the color to the expected value', () => {
+      expect(invertColor('#000000')).toBe('#FFFFFF');
+      expect(invertColor('#FFFFFF')).toBe('#000000');
+      expect(invertColor('#0E0099')).toBe('#F1FF66');
+      expect(invertColor('#00FF00')).toBe('#FF00FF');
+      expect(invertColor('#FF0100')).toBe('#00FEFF');
+    });
+  });
+
+  describe('when the color is provided as an RGB array', () => {
+    it('should invert the color to the expected value', () => {
+      expect(invertColor([0, 0, 0])).toBe('#FFFFFF');
+      expect(invertColor([255, 255, 255])).toBe('#000000');
+      expect(invertColor([121, 52, 38])).toBe('#86CBD9');
+    });
+  });
+
+  describe('when the color is provided as a string and the bw option is true', () => {
+    it('should return black for light colors and white for dark colors', () => {
+      expect(invertColor('#000000', { bw: true })).toBe('#FFFFFF');
+      expect(invertColor('FFFFFF', { bw: true })).toBe('#000000');
+      expect(invertColor('#400B06', { bw: true })).toBe('#FFFFFF');
+      expect(invertColor('C1EC00', { bw: true })).toBe('#000000');
+      expect(invertColor('#005856', { bw: true })).toBe('#FFFFFF');
+    });
+  });
+
+  describe('when the color is provided as an RGB array and the bw option is true', () => {
+    it('should return black for light colors and white for dark colors', () => {
+      expect(invertColor([0, 0, 0], { bw: true })).toBe('#FFFFFF');
+      expect(invertColor([255, 255, 255], { bw: true })).toBe('#000000');
+    });
+  });
+});

src/invertColor/invertColor.ts

@@ -0,0 +1,56 @@
+/**
+ * @name invertColor
+ * @description - Inverts the color by converting it to its complementary color.
+ *
+ * If the color is provided as a string, it should be in hexadecimal format (#RRGGBB).
+ * If the color is provided as an RGB array, it should be in the format [R, G, B].
+ * @param color - The color to invert.
+ * @param options.bw - If true, returns black (#000000) for light colors and white (#FFFFFF) for dark colors.
+ * @returns The inverted color in hexadecimal format (#RRGGBB).
+ */
+
+export type RGB = [red: number, green: number, blue: number];
+
+export function invertColor(color: string | RGB, options?: { bw: boolean }) {
+  let r, g, b;
+
+  if (typeof color === 'string') {
+    let hex = color;
+
+    if (hex.indexOf('#') === 0) {
+      hex = color.slice(1);
+    }
+    // convert 3-digit hex to 6-digits.
+    if (hex.length === 3) {
+      hex = hex[0] + hex[0] + hex[1] + hex[1] + hex[2] + hex[2];
+    }
+    if (hex.length !== 6) {
+      throw new Error('Invalid HEX color.');
+    }
+
+    r = parseInt(hex.substring(0, 2), 16);
+    g = parseInt(hex.substring(2, 4), 16);
+    b = parseInt(hex.substring(4, 6), 16);
+  } else {
+    r = color[0] as number;
+    g = color[1] as number;
+    b = color[2] as number;
+  }
+
+  if (options?.bw) {
+    // https://stackoverflow.com/a/3943023/112731
+    return r * 0.299 + g * 0.587 + b * 0.114 > 186 ? '#000000' : '#FFFFFF';
+  }
+
+  r = (255 - r).toString(16).toUpperCase();
+  g = (255 - g).toString(16).toUpperCase();
+  b = (255 - b).toString(16).toUpperCase();
+
+  return '#' + _padZero(r) + _padZero(g) + _padZero(b);
+}
+
+function _padZero(str: string, len: number = 2) {
+  len = len || 2;
+  const zeros = new Array(len).join('0');
+  return (zeros + str).slice(-len);
+}

src/main.d.ts

@@ -1,7 +1,7 @@
 export type RGB = [red: number, green: number, blue: number];
-export declare function getContrastColor(color: string | RGB, options?: {
-    returnAs: 'text' | 'hex' | 'rgb';
-}): number[] | "black" | "white" | "#000" | "#fff";
+export declare function invertColor(color: string | RGB, options?: {
+    bw: boolean;
+}): string;
 export declare function isEmpty(value: string | object | unknown[] | Set<unknown> | Map<unknown, unknown>): boolean;
 export declare function isNil(value: unknown): boolean;
 export declare function omit(object: Record<string, unknown>, properties: string | string[]): {

src/main.ts

@@ -1,4 +1,4 @@
-export * from './getContrastColor';
+export * from './invertColor';
 export * from './isEmpty';
 export * from './isNil';
 export * from './omit';