Add ASIN/ISBN fields to library and improve matching

Introduces `asin` and `isbn` fields to the PlexLibrary schema and database, with migration and indexing for fast lookups. Updates scan and recently-added processors to persist ASIN/ISBN from both Plex and Audiobookshelf backends. Enhances matching logic to prioritize exact ASIN matches using the new fields, improving match accuracy for Audiobookshelf users. Also includes minor improvements: fixes cover art handling for cached thumbnails, adds download URL validation in Prowlarr and qBittorrent integrations, and updates documentation to reflect these changes.

src/lib/utils/audiobook-matcher.ts

@@ -84,6 +84,8 @@ export async function findPlexMatch(
       plexGuid: true,
       title: true,
       author: true,
+      asin: true,    // Include ASIN field for direct matching
+      isbn: true,    // Include ISBN field for additional matching
     },
     take: 20,
   });
@@ -109,10 +111,27 @@ export async function findPlexMatch(
     return null;
   }
 
-  // PRIORITY 1: Check for EXACT ASIN match in plexGuid
+  // PRIORITY 1a: Check for EXACT ASIN match in dedicated field (works for all backends)
+  for (const plexBook of plexBooks) {
+    if (plexBook.asin && plexBook.asin.toLowerCase() === audiobook.asin.toLowerCase()) {
+      matchResult.matchType = 'asin_exact_field';
+      matchResult.matched = true;
+      matchResult.result = {
+        plexGuid: plexBook.plexGuid,
+        plexTitle: plexBook.title,
+        plexAuthor: plexBook.author,
+        asin: plexBook.asin,
+        confidence: 100,
+      };
+      if (DEBUG_ENABLED) console.log(JSON.stringify({ MATCHER: matchResult }));
+      return plexBook;
+    }
+  }
+
+  // PRIORITY 1b: Check for ASIN in plexGuid (backward compatibility for Plex)
   for (const plexBook of plexBooks) {
     if (plexBook.plexGuid && plexBook.plexGuid.includes(audiobook.asin)) {
-      matchResult.matchType = 'asin_exact';
+      matchResult.matchType = 'asin_exact_guid';
       matchResult.matched = true;
       matchResult.result = {
         plexGuid: plexBook.plexGuid,
@@ -125,10 +144,20 @@ export async function findPlexMatch(
     }
   }
 
-  // FILTER OUT candidates with wrong ASINs in plexGuid
+  // FILTER OUT candidates with wrong ASINs (check both dedicated field and plexGuid)
   const ASIN_PATTERN = /[A-Z0-9]{10}/g;
   const rejectedAsins: string[] = [];
   const validCandidates = plexBooks.filter((plexBook) => {
+    // Check dedicated ASIN field first (more reliable)
+    if (plexBook.asin) {
+      if (plexBook.asin.toLowerCase() !== audiobook.asin.toLowerCase()) {
+        rejectedAsins.push(plexBook.asin);
+        return false; // Wrong ASIN in dedicated field - reject
+      }
+      return true; // Correct ASIN in dedicated field - keep
+    }
+
+    // Fall back to checking plexGuid for legacy Plex data
     if (!plexBook.plexGuid) return true;
     const asinsInGuid = plexBook.plexGuid.match(ASIN_PATTERN);
     if (!asinsInGuid || asinsInGuid.length === 0) return true;

src/lib/utils/file-organizer.ts

@@ -393,18 +393,32 @@ export class FileOrganizer {
   }
 
   /**
-   * Download cover art from URL
+   * Download cover art from URL or copy from local cache
    */
   private async downloadCoverArt(url: string, targetDir: string): Promise<void> {
     const targetPath = path.join(targetDir, 'cover.jpg');
 
     try {
-      const response = await axios.get(url, {
-        responseType: 'arraybuffer',
-        timeout: 30000,
-      });
+      // Check if this is a cached thumbnail (local file)
+      if (url.startsWith('/api/cache/thumbnails/')) {
+        // Extract filename from the API path
+        const filename = url.replace('/api/cache/thumbnails/', '');
+        const cachedPath = path.join('/app/cache/thumbnails', filename);
 
-      await fs.writeFile(targetPath, response.data);
+        // Copy from local cache instead of downloading
+        const coverData = await fs.readFile(cachedPath);
+        await fs.writeFile(targetPath, coverData, { mode: 0o644 });
+        console.log(`[FileOrganizer] Copied cover art from cache: ${filename}`);
+      } else {
+        // Download from external URL (e.g., Audible CDN)
+        const response = await axios.get(url, {
+          responseType: 'arraybuffer',
+          timeout: 30000,
+        });
+
+        await fs.writeFile(targetPath, response.data);
+        console.log(`[FileOrganizer] Downloaded cover art from URL`);
+      }
     } catch (error) {
       console.error('[FileOrganizer] Failed to download cover art:', error);
       throw error;