feat: add support for loading custom themes from files (#2218)

* feat: add support for loading custom themes from files

---------

Co-authored-by: jeffvli <jeffvictorli@gmail.com>

src/preload/custom-themes.ts

@@ -0,0 +1,42 @@
+import { ipcRenderer } from 'electron';
+
+export interface CustomTheme {
+    app?: Record<string, unknown>;
+    colors?: Record<string, unknown>;
+    error?: string;
+    extends?: string;
+    filename: string;
+    id: string;
+    label: string;
+    mantineOverride?: Record<string, unknown>;
+    mode: 'dark' | 'light';
+    stylesheetContents?: string[];
+    warnings?: string[];
+}
+
+const get = async (): Promise<CustomTheme[]> => {
+    return ipcRenderer.invoke('custom-themes-get');
+};
+
+const reload = async (): Promise<CustomTheme[]> => {
+    return ipcRenderer.invoke('custom-themes-reload');
+};
+
+const openFolder = async (): Promise<boolean> => {
+    return ipcRenderer.invoke('custom-themes-open-folder');
+};
+
+const onUpdate = (cb: (themes: CustomTheme[]) => void) => {
+    const listener = (_event: Electron.IpcRendererEvent, themes: CustomTheme[]) => cb(themes);
+    ipcRenderer.on('custom-themes-updated', listener);
+    return () => ipcRenderer.removeListener('custom-themes-updated', listener);
+};
+
+export const customThemes = {
+    get,
+    onUpdate,
+    openFolder,
+    reload,
+};
+
+export type CustomThemes = typeof customThemes;

src/preload/index.ts

@@ -2,6 +2,7 @@ import { contextBridge, webUtils } from 'electron';
 
 import { autodiscover } from './autodiscover';
 import { browser } from './browser';
+import { customThemes } from './custom-themes';
 import { discordRpc } from './discord-rpc';
 import { ipc } from './ipc';
 import { localSettings } from './local-settings';
@@ -16,6 +17,7 @@ import { visualizer } from './visualizer';
 const api = {
     autodiscover,
     browser,
+    customThemes,
     discordRpc,
     getPathForFile: webUtils.getPathForFile,
     ipc,