Manga Bookshelf: Track Volumes and Search Before Purchase

§Verification Before Purchase and Defining Registration Units

This digital bookshelf tool helps prevent accidentally buying manga volumes you already own. When browsing in a bookstore, it is common to forget whether you have a specific volume. This browser tool lets you maintain a localized record of your collection and search it before making a purchase.

The core rule is that each record represents exactly one volume. It is not designed to store a series as a single entry by updating one number for the latest volume. If you own volumes 1, 2, and 3, you must create three separate records. This allows tracking irregular collections, like missing a middle volume.

You input the title, volume number, optional author, and optional cover. There is no bulk registration; you must register each volume one by one.

Data is stored exclusively in the browser's IndexedDB on the specific device you use. The code utilizes the Dexie library to manage the BookshelfDatabase, which should not be confused with the simpler LocalStorage API. There is no account system or cloud server. Without automatic synchronization, you must use the exact device you carry to the store.

Before buying, search for the title. If the volume appears, it serves as a reference, though it does not guarantee actual ownership due to potential unrecorded differences like different editions. If it does not appear, it does not definitively mean you do not own it, as there could be missing entries or typos. The tool's reliability depends entirely on your consistent manual registration of new purchases.

§Manual Registration and Updating Records

Click the + button to open the form. Enter a series title and a whole volume number from 1 to 999. You can also enter an author and add a cover. The title and author fields each allow up to 120 characters in both languages. The English version allows duplicate entries, so check your bookshelf for the same title and volume before saving.

The tool cannot automatically categorize physical versus digital copies, or standard versus special editions. You must create your own naming rules. If you own volume 1 physically and volume 2 digitally, append terms like "(Digital)" to the title. Registering them under identical base titles makes distinguishing formats impossible later.

If you find a typo in a title or an incorrect volume, you cannot directly edit the record. The tool lacks an editing interface for modifying specific fields. To fix a mistake, you must delete the flawed record completely and register it again.

Before deleting via the details screen, manually note down the current details. Because there is no undo function, a confirmation dialog will appear to ensure you want to proceed. Once confirmed and deleted, data is instantly removed from the database. Open the new registration form, input the corrected details, and submit to restore it.

§ISBN Assistance and External Communication

To fill in the title, author, or cover from a lookup, enter a valid ISBN-13. The tool checks the check digit before starting the search. You can still register the volume manually if the lookup returns no result.

When you manually trigger an ISBN search, the tool initiates external communication. It first queries the "openBD" API, which covers Japanese publications. If no data is found, it communicates with the "Google Books API" as a fallback. During this process, the ISBN code you entered, along with standard connection data like your IP address, is transmitted over the internet to the openBD and Google servers. Fetching the cover image also involves communicating with image hosting servers.

Importantly, the tool does not send your entire bookshelf inventory or collection history to these external APIs. The data used for the query is the single ISBN, though communication metadata like IP addresses is also transmitted.

An ISBN fetch might fail for many reasons. While various factors are involved, failure is not strictly determined by a specific type of book or publication status. Your device might simply be offline. Temporary server outages can also cause failures. The tool cannot diagnose the exact cause. In these instances, you must manually type all information.

§Pre-Purchase Search and Determining Missing Volumes

The bookshelf provides bookshelf (grouped by series with spine-like ascending volumes) and grid views to help visually confirm your collection. As your records grow, finding a book manually becomes difficult, so a text search feature is available. This search filters the local database by matching your input against saved series titles and author names.

The search uses simple partial match logic. Typing "Fantasy" displays any record containing that word in the title or author fields. This filters the records loaded from IndexedDB using JavaScript to perform a partial match on titles and authors by converting to lowercase. It does not execute a database query for every search, separating the initial display communication from local filtering. There are no advanced filters like genre tags or release date sorting.

This independent record system requires specific habits to identify missing volumes. If you own volumes 1, 2, 4, and 5, your bookshelf displays exactly those four records. When searching the title at a store, the visual absence of volume 3 is your indicator that you do not own it. The tool lacks an automated feature to alert you.

For series using non-numeric formats like "Upper Volume," you can type these descriptions into the title while using numbers in the volume field for sorting. If you share a collection with a roommate, you must manually register their books on your device.

§Storage Scope, Manual Backups, and Browser Limitations

The tool stores all registered manga records in the browser's "IndexedDB," a client-side storage area. This data is strictly confined to the specific browser on the specific device used for registration. Data entered on Safari on a phone will not appear on Chrome on the same phone. The English and Japanese versions operate on the same origin and share the exact same database. Switching the language changes the interface reading the local data; it does not sync to a different device.

Because data relies entirely on browser storage, permanent retention is never guaranteed. Clearing this site's IndexedDB data will erase your records. Furthermore, data retention is never guaranteed due to potential device or browser failures, private browsing modes, or storage capacity limits. Note that this uses IndexedDB, not the LocalStorage API.

Crucially, this tool lacks automatic cloud backups and does not support exporting data to CSV or JSON files. There is no built-in restoration mechanism if the database is cleared. Therefore, to maintain a permanent inventory of a large collection, you must manually create a backup using a spreadsheet or physical notebook.

§Fetch Failures, Missing Data, and Manual Covers

Even when communication with openBD or Google Books succeeds, the retrieved data may be incomplete. The external database might provide a title but lack an author or cover image. Frequently, it returns the title and volume combined as a single string. The tool attempts to parse this text to separate the numeric volume. If the text contains unusual numbering, this parsing may fail, leaving the volume field blank or the title cluttered.

When missing data occurs, you must rely on manual input. Review the fetched information and use your keyboard to fill missing fields or correct titles before saving. If a fetched title does not match your naming rules, edit it manually to maintain consistency in your grid.

You can add a custom cover image to improve visual identification by uploading a file or using your device's camera. Using the camera for cover files is separate from the camera used for ISBN barcodes (which requires the BarcodeDetector API and browser permissions). A lack of BarcodeDetector support does not necessarily prevent capturing a cover image file.

The tool provides basic image adjustments. You can drag the image to reposition it and use a slider to adjust the zoom scale. Adjustments are made using a slider and dragging; pinch-to-zoom is not implemented. Manage image rights responsibly on your devices, as downloads are not unconditionally guaranteed to be legal.

§Operational Cases and Frequently Asked Questions

We outline features omitted from this tool and address common questions. It excludes complex functionalities of library software.

There are no statistical graphs or indicators for whether a series is completed, although the number of volumes per series group is displayed on the screen. It does not track release dates, send notifications, or offer custom tags.

Here are specific FAQs regarding the tool:

"Q: If I buy a new phone, what happens to my data?"

A: Data is stored entirely within the old device's browser, and the tool itself lacks an automatic sync or standard transfer function. Opening the URL on a new phone will not sync your data. You may need to manually re-register your collection, as we have not verified whether standard OS-level device migration features can successfully recover browser databases.

"Q: I cleared my browser data. Can I restore my records?"

A: No. The tool lacks backup features. There is no mechanism to retrieve lost records. You must re-enter everything.

"Q: Why does the cover image not appear when I enter an ISBN?"

A: This could be due to communication issues, the external database lacking the image, or a retrieval processing failure. You can manually provide your own image file.

"Q: Can I register without using a camera?"

A: Yes, you can manually input the information without a camera.

References

These primary sources relate to the display and communication mechanisms used by the tool, but they do not guarantee complete specification compliance.