Complete Phase C (custom commands & yt-dlp updater) and Phase D (library, UX & notifications)

Phase C had been implemented in the working tree but never committed:
named custom-command templates (CRUD + per-download override), command
preview, and the in-app yt-dlp self-updater.

Phase D adds: history search/kind-filter/multi-select/bulk-delete/
re-download; native OS notifications on completion/failure; a private/
incognito download mode that skips history; settings+template backup/
restore via JSON; and a persistent error log surfaced as a Diagnostics
report in Settings.

See ROADMAP.md for the full per-item breakdown.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/main/index.ts

@@ -5,16 +5,21 @@ import {
   IpcChannels,
   type StartDownloadOptions,
   type Settings,
-  type HistoryEntry
+  type HistoryEntry,
+  type CommandTemplate,
+  type YtdlpUpdateChannel
 } from '@shared/ipc'
-import { getYtdlpVersion } from './ytdlp'
+import { getYtdlpVersion, updateYtdlp } from './ytdlp'
 import { probeMedia } from './probe'
-import { startDownload, cancelDownload } from './download'
+import { startDownload, cancelDownload, previewCommand } from './download'
 import { getSettings, setSettings } from './settings'
-import { listHistory, addHistory, removeHistory, clearHistory } from './history'
+import { listHistory, addHistory, removeHistory, removeManyHistory, clearHistory } from './history'
+import { listTemplates, saveTemplate, removeTemplate } from './templates'
 import { setupPortableData } from './portable'
 import { safeOpenPath, safeShowInFolder } from './reveal'
 import { openCookieLoginWindow, getCookiesStatus, clearCookies } from './cookies'
+import { listErrorLog, addErrorLog, clearErrorLog } from './errorlog'
+import { exportBackup, importBackup } from './backup'
 
 // Force software compositing (GPU acceleration off). On this dev machine's old GeForce
 // GT 625 — and plausibly on the old / locked-down public PCs this app targets —
@@ -86,9 +91,21 @@ function registerIpcHandlers(): void {
 
   ipcMain.handle(IpcChannels.probe, (_e, url: string) => probeMedia(url))
 
-  ipcMain.handle(IpcChannels.downloadStart, (e, opts: StartDownloadOptions) =>
-    startDownload(e.sender, opts)
-  )
+  ipcMain.handle(IpcChannels.downloadStart, (e, opts: StartDownloadOptions) => {
+    const result = startDownload(e.sender, opts)
+    // Pre-spawn failures (missing yt-dlp.exe, bad URL, duplicate id) never reach
+    // download.ts's own close/error handlers, so log them here instead.
+    if (!result.ok) {
+      addErrorLog({
+        id: opts.id,
+        url: opts.url,
+        kind: opts.kind,
+        error: result.error ?? 'Unknown error',
+        occurredAt: Date.now()
+      })
+    }
+    return result
+  })
   ipcMain.handle(IpcChannels.downloadCancel, (_e, id: string) => cancelDownload(id))
 
   ipcMain.handle(IpcChannels.defaultFolder, () => app.getPath('downloads'))
@@ -121,11 +138,37 @@ function registerIpcHandlers(): void {
   ipcMain.handle(IpcChannels.historyList, () => listHistory())
   ipcMain.handle(IpcChannels.historyAdd, (_e, entry: HistoryEntry) => addHistory(entry))
   ipcMain.handle(IpcChannels.historyRemove, (_e, id: string) => removeHistory(id))
+  ipcMain.handle(IpcChannels.historyRemoveMany, (_e, ids: string[]) => removeManyHistory(ids))
   ipcMain.handle(IpcChannels.historyClear, () => clearHistory())
 
   ipcMain.handle(IpcChannels.cookiesLogin, (_e, url: string) => openCookieLoginWindow(url))
   ipcMain.handle(IpcChannels.cookiesStatus, () => getCookiesStatus())
   ipcMain.handle(IpcChannels.cookiesClear, () => clearCookies())
+
+  ipcMain.handle(IpcChannels.templatesList, () => listTemplates())
+  ipcMain.handle(IpcChannels.templatesSave, (_e, template: CommandTemplate) => saveTemplate(template))
+  ipcMain.handle(IpcChannels.templatesRemove, (_e, id: string) => removeTemplate(id))
+
+  ipcMain.handle(IpcChannels.commandPreview, (_e, opts: StartDownloadOptions) =>
+    previewCommand(opts)
+  )
+
+  ipcMain.handle(IpcChannels.ytdlpUpdate, (_e, channel: YtdlpUpdateChannel) => updateYtdlp(channel))
+
+  ipcMain.handle(IpcChannels.errorLogList, () => listErrorLog())
+  ipcMain.handle(IpcChannels.errorLogClear, () => clearErrorLog())
+
+  ipcMain.handle(IpcChannels.backupExport, (e) =>
+    exportBackup(BrowserWindow.fromWebContents(e.sender) ?? undefined)
+  )
+  ipcMain.handle(IpcChannels.backupImport, async (e) => {
+    const win = BrowserWindow.fromWebContents(e.sender) ?? undefined
+    const result = await importBackup(win)
+    // A restored backup may have changed the theme; keep the native window
+    // background in sync the same way settingsSet does.
+    if (result.ok) win?.setBackgroundColor(THEME_BACKGROUND[getSettings().theme])
+    return result
+  })
 }
 
 app.whenReady().then(() => {