utils/tailwind.ts: Tailwind/SoapboxConfig conversion functions

app/soapbox/types/colors.ts

@@ -6,5 +6,5 @@ export type TailwindColorObject = {
 };
 
 export type TailwindColorPalette = {
-  [key: string]: TailwindColorObject,
+  [key: string]: TailwindColorObject | string,
 }

app/soapbox/utils/tailwind.ts

@@ -0,0 +1,44 @@
+import { Map as ImmutableMap, fromJS } from 'immutable';
+
+import tintify from 'soapbox/utils/colors';
+
+import type { TailwindColorPalette } from 'soapbox/types/colors';
+
+type SoapboxConfig = ImmutableMap<string, any>;
+type SoapboxColors = ImmutableMap<string, any>;
+
+/** Check if the value is a valid hex color */
+const isHex = (value: any): boolean => /^#([0-9A-F]{3}){1,2}$/i.test(value);
+
+/** Expand hex colors into tints */
+export const expandPalette = (palette: TailwindColorPalette): TailwindColorPalette => {
+  // Generate palette only for present colors
+  return Object.entries(palette).reduce((result: TailwindColorPalette, colorData) => {
+    const [colorName, color] = colorData;
+
+    // Conditionally handle hex color and Tailwind color object
+    if (typeof color === 'string' && isHex(color)) {
+      result[colorName] = tintify(color);
+    } else if (typeof color === 'object') {
+      result[colorName] = color;
+    }
+
+    return result;
+  }, {});
+};
+
+/** Build a color object from legacy colors */
+export const fromLegacyColors = (soapboxConfig: SoapboxConfig): TailwindColorPalette => {
+  return expandPalette({
+    primary: soapboxConfig.get('brandColor'),
+    accent: soapboxConfig.get('accentColor'),
+  });
+};
+
+/** Convert Soapbox Config into Tailwind colors */
+export const toTailwind = (soapboxConfig: SoapboxConfig): SoapboxColors => {
+  const colors: SoapboxColors = ImmutableMap(soapboxConfig.get('colors'));
+  const legacyColors: SoapboxColors = ImmutableMap(fromJS(fromLegacyColors(soapboxConfig)));
+
+  return legacyColors.mergeDeep(colors);
+};