feat: select directory to save last book cover image (#2521)

apps/readest-app/src/app/reader/hooks/useAutoSaveBookCover.ts

@@ -1,11 +1,14 @@
 import { useCallback, useEffect } from 'react';
 import { useEnv } from '@/context/EnvContext';
+import { useTranslation } from '@/hooks/useTranslation';
 import { useBookDataStore } from '@/store/bookDataStore';
 import { useSettingsStore } from '@/store/settingsStore';
 import { throttle } from '@/utils/throttle';
 import { getCoverFilename } from '@/utils/book';
+import { eventDispatcher } from '@/utils/event';
 
 export const useBookCoverAutoSave = (bookKey: string) => {
+  const _ = useTranslation();
   const { envConfig, appService } = useEnv();
 
   // eslint-disable-next-line react-hooks/exhaustive-deps
@@ -17,15 +20,31 @@ export const useBookCoverAutoSave = (bookKey: string) => {
           const bookData = useBookDataStore.getState().getBookData(bookKey);
           const book = bookData?.book;
           const savedBookHash = settings.savedBookCoverForLockScreen;
+          const savedCoverPath = settings.savedBookCoverForLockScreenPath;
           if (appService && book && savedBookHash && savedBookHash !== book?.hash) {
             const coverPath = await appService.resolveFilePath(getCoverFilename(book), 'Books');
             try {
-              await appService.copyFile(coverPath, 'last-book-cover.png', 'Images');
+              const lastCoverFilename = 'last-book-cover.png';
+              const builtinImagesPath = await appService.resolveFilePath('', 'Images');
+              if (!savedCoverPath || savedCoverPath === builtinImagesPath) {
+                await appService.copyFile(coverPath, lastCoverFilename, 'Images');
+              } else {
+                await appService.copyFile(
+                  coverPath,
+                  `${savedCoverPath}/${lastCoverFilename}`,
+                  'None',
+                );
+              }
               settings.savedBookCoverForLockScreen = book.hash;
               useSettingsStore.getState().setSettings(settings);
               useSettingsStore.getState().saveSettings(envConfig, settings);
             } catch (error) {
-              console.error('Failed to auto-save book cover for lock screen:', error);
+              eventDispatcher.dispatch('toast', {
+                type: 'error',
+                message: _('Failed to auto-save book cover for lock screen: {{error}}', {
+                  error: error instanceof Error ? error.message : String(error),
+                }),
+              });
             }
           }
         }, 5000);