don't block during scan

src/lib/comics.ts

@@ -126,10 +126,18 @@ export function scanComicsLibrary(
   return results.sort((a, b) => naturalCompare(a.title, b.title))
 }
 
-// comicsFromDb returns series + standalone issues for the top-level grid.
+function escapeLike(s: string): string {
+  return `%${s.replace(/%/g, '\\%').replace(/_/g, '\\_')}%`
+}
+
+// comicsFromDb returns series + standalone issues for the top-level grid, paginated.
 // Series issues are retrieved separately via comicIssuesFromDb.
-export function comicsFromDb(libraryId: string): (ComicIssue | ComicSeries)[] {
+export function comicsFromDb(
+  libraryId: string,
+  opts: { page: number; pageSize: number; search?: string }
+): { items: (ComicIssue | ComicSeries)[]; total: number } {
   const db = getDb()
+  const offset = (opts.page - 1) * opts.pageSize
 
   type DbRow = {
     item_key: string
@@ -140,59 +148,63 @@ export function comicsFromDb(libraryId: string): (ComicIssue | ComicSeries)[] {
     file_path: string | null
   }
 
-  const allRows = db
-    .prepare(
-      `SELECT item_key, item_type, parent_key, title, metadata, file_path
-       FROM media_items
-       WHERE library_id = ? AND item_type IN ('comic_series','comic_issue')
-       ORDER BY title`
-    )
-    .all(libraryId) as DbRow[]
+  const baseWhere = `
+    WHERE library_id = ?
+      AND (item_type = 'comic_series' OR (item_type = 'comic_issue' AND parent_key IS NULL))
+  `
 
-  const seriesMap = new Map<string, ComicSeries>()
-  const standaloneIssues: ComicIssue[] = []
+  const total: number = opts.search
+    ? (db
+        .prepare(`SELECT COUNT(*) as cnt FROM media_items ${baseWhere} AND title LIKE ? ESCAPE '\\'`)
+        .get(libraryId, escapeLike(opts.search)) as { cnt: number }).cnt
+    : (db
+        .prepare(`SELECT COUNT(*) as cnt FROM media_items ${baseWhere}`)
+        .get(libraryId) as { cnt: number }).cnt
 
-  for (const row of allRows) {
-    if (row.item_type !== 'comic_series') continue
+  const rows: DbRow[] = opts.search
+    ? db
+        .prepare(
+          `SELECT item_key, item_type, parent_key, title, metadata, file_path
+           FROM media_items ${baseWhere} AND title LIKE ? ESCAPE '\\'
+           ORDER BY title LIMIT ? OFFSET ?`
+        )
+        .all(libraryId, escapeLike(opts.search), opts.pageSize, offset) as DbRow[]
+    : db
+        .prepare(
+          `SELECT item_key, item_type, parent_key, title, metadata, file_path
+           FROM media_items ${baseWhere}
+           ORDER BY title LIMIT ? OFFSET ?`
+        )
+        .all(libraryId, opts.pageSize, offset) as DbRow[]
+
+  const items: (ComicIssue | ComicSeries)[] = []
+  for (const row of rows) {
     const meta = row.metadata ? JSON.parse(row.metadata) : {}
-    const idPart = row.item_key.split(':comic_series:')[1] ?? row.item_key
-    seriesMap.set(row.item_key, {
-      id: idPart,
-      item_key: row.item_key,
-      title: row.title ?? decodeURIComponent(idPart),
-      coverUrl: meta.coverUrl ?? null,
-      issueCount: meta.issueCount ?? 0,
-    })
-  }
-
-  for (const row of allRows) {
-    if (row.item_type !== 'comic_issue') continue
-    const meta = row.metadata ? JSON.parse(row.metadata) : {}
-    const idPart = row.item_key.split(':comic_issue:')[1] ?? row.item_key
-    const issue: ComicIssue = {
-      id: idPart,
-      item_key: row.item_key,
-      title: row.title ?? decodeURIComponent(idPart.split(':').pop() ?? idPart),
-      issueNumber: meta.issueNumber ?? null,
-      pageCount: meta.pageCount ?? 0,
-      coverUrl: meta.coverUrl ?? null,
-      filePath: row.file_path ?? '',
-      isStandalone: meta.isStandalone ?? false,
-    }
-
-    if (row.parent_key && seriesMap.has(row.parent_key)) {
-      // Series issues are not included in the top-level grid — series card represents them
-      // We only include series cards + standalone issues in the grid
+    if (row.item_type === 'comic_series') {
+      const idPart = row.item_key.split(':comic_series:')[1] ?? row.item_key
+      items.push({
+        id: idPart,
+        item_key: row.item_key,
+        title: row.title ?? decodeURIComponent(idPart),
+        coverUrl: meta.coverUrl ?? null,
+        issueCount: meta.issueCount ?? 0,
+      } as ComicSeries)
     } else {
-      standaloneIssues.push(issue)
+      const idPart = row.item_key.split(':comic_issue:')[1] ?? row.item_key
+      items.push({
+        id: idPart,
+        item_key: row.item_key,
+        title: row.title ?? decodeURIComponent(idPart.split(':').pop() ?? idPart),
+        issueNumber: meta.issueNumber ?? null,
+        pageCount: meta.pageCount ?? 0,
+        coverUrl: meta.coverUrl ?? null,
+        filePath: row.file_path ?? '',
+        isStandalone: meta.isStandalone ?? true,
+      } as ComicIssue)
     }
   }
 
-  const results: (ComicIssue | ComicSeries)[] = [
-    ...Array.from(seriesMap.values()),
-    ...standaloneIssues,
-  ]
-  return results.sort((a, b) => naturalCompare(a.title, b.title))
+  return { items, total }
 }
 
 export function comicIssuesFromDb(libraryId: string, seriesId: string): ComicIssue[] {

src/lib/db.ts

@@ -110,6 +110,7 @@ function initDb(db: Database.Database): void {
   migrateLibrariesAddComics(db)
   migrateComicItemTypes(db)
   migrateImportedTags(db)
+  migrateComicsIndex(db)
   seedAppSettings(db)
 }
 
@@ -447,3 +448,10 @@ function migrateImportedTags(db: Database.Database): void {
     );
   `)
 }
+
+function migrateComicsIndex(db: Database.Database): void {
+  db.exec(`
+    CREATE INDEX IF NOT EXISTS media_items_library_type_title
+      ON media_items(library_id, item_type, title);
+  `)
+}

src/lib/scanner.ts

@@ -573,29 +573,37 @@ async function scanComics(library: Library, libraryRoot: string): Promise<void>
       scanned_at = excluded.scanned_at
   `)
 
+  type SeriesRec = Parameters<typeof upsertSeries.run>[0]
+  type IssueRec  = Parameters<typeof upsertIssue.run>[0]
+  type BatchEntry = { type: 'series'; rec: SeriesRec } | { type: 'issue'; rec: IssueRec }
+
+  // Collect all records before touching the DB so we can batch-insert with event-loop yields.
+  // Note: between clearLibraryItems and the final batch, the library will appear partially
+  // populated — acceptable for a background scan.
+  const allRecords: BatchEntry[] = []
   let issueCount = 0
 
-  db.transaction(() => {
-    for (const item of items) {
-      if ('issues' in item) {
-        const series = item as ScannedComicSeries
-        const seriesKey = `${library.id}:comic_series:${series.id}`
-        upsertSeries.run({
+  for (const item of items) {
+    if ('issues' in item) {
+      const series = item as ScannedComicSeries
+      const seriesKey = `${library.id}:comic_series:${series.id}`
+      allRecords.push({
+        type: 'series',
+        rec: {
           library_id: library.id,
           item_key: seriesKey,
           item_type: 'comic_series',
           title: series.title,
-          metadata: JSON.stringify({
-            issueCount: series.issueCount,
-            coverUrl: series.coverUrl,
-          }),
+          metadata: JSON.stringify({ issueCount: series.issueCount, coverUrl: series.coverUrl }),
           file_path: null,
           scanned_at: now,
-        })
-
-        for (const issue of series.issues) {
-          const issueKey = `${library.id}:comic_issue:${issue.id}`
-          upsertIssue.run({
+        },
+      })
+      for (const issue of series.issues) {
+        const issueKey = `${library.id}:comic_issue:${issue.id}`
+        allRecords.push({
+          type: 'issue',
+          rec: {
             library_id: library.id,
             item_key: issueKey,
             item_type: 'comic_issue',
@@ -609,13 +617,16 @@ async function scanComics(library: Library, libraryRoot: string): Promise<void>
             }),
             file_path: issue.filePath,
             scanned_at: now,
-          })
-          issueCount++
-        }
-      } else {
-        const issue = item as ComicIssue
-        const issueKey = `${library.id}:comic_issue:${issue.id}`
-        upsertIssue.run({
+          },
+        })
+        issueCount++
+      }
+    } else {
+      const issue = item as ComicIssue
+      const issueKey = `${library.id}:comic_issue:${issue.id}`
+      allRecords.push({
+        type: 'issue',
+        rec: {
           library_id: library.id,
           item_key: issueKey,
           item_type: 'comic_issue',
@@ -629,13 +640,27 @@ async function scanComics(library: Library, libraryRoot: string): Promise<void>
           }),
           file_path: issue.filePath,
           scanned_at: now,
-        })
-        issueCount++
-      }
+        },
+      })
+      issueCount++
     }
-  })()
+  }
 
-  // Prewarm CBZ cover thumbnails
+  // Insert in batches of 500, yielding the event loop between batches so the app
+  // remains responsive to HTTP requests during a large scan.
+  const BATCH_SIZE = 500
+  for (let i = 0; i < allRecords.length; i += BATCH_SIZE) {
+    const batch = allRecords.slice(i, i + BATCH_SIZE)
+    db.transaction(() => {
+      for (const entry of batch) {
+        if (entry.type === 'series') upsertSeries.run(entry.rec)
+        else upsertIssue.run(entry.rec)
+      }
+    })()
+    await new Promise<void>((r) => setImmediate(r))
+  }
+
+  // Prewarm CBZ cover thumbnails — fire-and-forget so they don't block scan completion.
   for (const item of items) {
     const issuesToWarm: ComicIssue[] = 'issues' in item
       ? (item as ScannedComicSeries).issues.slice(0, 1)
@@ -643,11 +668,9 @@ async function scanComics(library: Library, libraryRoot: string): Promise<void>
 
     for (const issue of issuesToWarm) {
       const absPath = path.join(libraryRoot, issue.filePath)
-      try {
-        await getCbzThumbnailPath(absPath, library.id)
-      } catch (err) {
+      getCbzThumbnailPath(absPath, library.id).catch((err) => {
         console.warn(`[scanner]   Could not generate CBZ thumbnail for ${issue.filePath}:`, err instanceof Error ? err.message : err)
-      }
+      })
     }
   }