Allow users to select multiple books (e.g., individual mp3 files improperly imported as separate books) and "Merge" them into a single book. This involves moving all files to a single folder and updating the database to reflect a single library item containing all files.
- **Validation**: Ensure user has update/delete permissions. Check all items belong to the same library and are books.
- **Primary Item Selection**: Use the first selected item as the "primary" item (the one that will act as the container).
- **Target Folder**: Determine the target folder path.
- If the primary item is already in a suitable folder (e.g. `Author/Title`), use it.
- If the items are in the root or disorganized, create a new folder based on the primary item's metadata (Author/Title).
- **File Operations**:
- Iterate through all _other_ selected items.
- Move their media files (audio, ebook, cover) to the target folder.
- Handle filename collisions (append counter if needed).
- Update `LibraryItem` entries? No, we will rescind the primary item.
- **Database Updates**:
- Delete the _other_`LibraryItem` records from the database.
- Trigger a rescan of the primary item's folder to pick up the new files and update tracks/chapters.
- Clean up empty source folders of the moved items.
#### [MODIFY] `server/routers/ApiRouter.js`
- Add `POST /items/batch/merge` route mapped to `LibraryItemController.batchMerge`.
### Frontend
#### [MODIFY] `client/components/app/Appbar.vue`
- Update `contextMenuItems` computed property.
- Add "Merge" option when:
- User has update/delete permissions.
- Library is a "book" library.
- Multiple items are selected (`selectedMediaItems.length > 1`).
- Implement `batchMerge()` method to call the API.
- Add confirmation dialog explaining what will happen.
## Verification Plan
### Manual Verification
1.**Setup**:
- Add multiple individual mp3 files to the root of a library (or separate folders) so they show up as separate books.
- Ensure they have some metadata (Title/Author) or add it manually.
2.**Execution**:
- Go to the library in the web UI.
- Select the multiple "books" (mp3 files).
- Click the Multi-select "x items selected" bar if not already open (it opens automatically on selection).
- Click the Context Menu (3 dots) or find the "Merge" button (to be added).
- Select "Merge".
- Confirm the dialog.
3.**Result Validation**:
- Verify that the separate books disappear.
- Verify that one single book remains.
- Open the remaining book and check "Files" tab. It should contain all the mp3 files.
- Check the filesystem: Ensure all mp3 files are now in the same folder.
- Check metadata: Ensure the book plays correctly.
## Walkthrough
# Merge Books Feature Walkthrough
I have implemented the "Merge Books" feature, which allows users to combine multiple library items (specifically books) into a single library item. This is particularly useful for fixing issues where individual audio files were imported as separate books.
✔ should merge two file-based items into a new folder
1 passing (113ms)
```
### Manual Verification Steps
1.**Identify Split Books**: Find a set of books in your library that should be a single book (e.g., "Chapter 1", "Chapter 2" showing as separate books).
2.**Select Books**: Enable multi-select and click on the books you want to merge.
3.**Click Merge**: In the top URI bar, click the menu button (3 dots) and select **Merge**.
4.**Confirm**: Accept the confirmation dialog ("Are you sure you want to merge...").
5.**Verify**:
- The separate books should disappear.
- A single book should remain (based on the first selected book).
- Open the book and check the "Files" tab. It should contain all the audio files.
- Play the book to ensure tracks are ordered and playable.
