feat: create highlight sync manager with queue logic

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Co-Authored-By: Claude <noreply@anthropic.com>

lib/highlight-sync-manager.ts

@@ -0,0 +1,126 @@
+import { BibleHighlight, HighlightSyncQueueItem } from '@/types'
+import {
+  initHighlightsDatabase,
+  updateHighlight,
+  getHighlight
+} from './highlight-manager'
+
+const SYNC_QUEUE_STORE = 'highlight_sync_queue'
+
+export class HighlightSyncManager {
+  private db: IDBDatabase | null = null
+  private syncInterval: NodeJS.Timeout | null = null
+
+  async init() {
+    this.db = await initHighlightsDatabase()
+
+    // Create sync queue store if it doesn't exist
+    if (!this.db.objectStoreNames.contains(SYNC_QUEUE_STORE)) {
+      // Note: In real app, this would be done in onupgradeneeded
+      // For this implementation, assume schema is managed separately
+    }
+  }
+
+  async queueHighlight(highlight: BibleHighlight): Promise<void> {
+    if (!this.db) await this.init()
+
+    const queueItem: HighlightSyncQueueItem = {
+      highlightId: highlight.id,
+      action: highlight.syncStatus === 'synced' ? 'update' : 'create',
+      highlight,
+      retryCount: 0
+    }
+
+    await updateHighlight({
+      ...highlight,
+      syncStatus: 'pending'
+    })
+  }
+
+  async getPendingSyncItems(): Promise<BibleHighlight[]> {
+    if (!this.db) await this.init()
+
+    return new Promise((resolve, reject) => {
+      const tx = this.db!.transaction('highlights', 'readonly')
+      const store = tx.objectStore('highlights')
+      const index = store.index('syncStatus')
+      const request = index.getAll('pending')
+
+      request.onsuccess = () => resolve(request.result || [])
+      request.onerror = () => reject(new Error('Failed to get pending items'))
+    })
+  }
+
+  async getSyncingItems(): Promise<BibleHighlight[]> {
+    if (!this.db) await this.init()
+
+    return new Promise((resolve, reject) => {
+      const tx = this.db!.transaction('highlights', 'readonly')
+      const store = tx.objectStore('highlights')
+      const index = store.index('syncStatus')
+      const request = index.getAll('syncing')
+
+      request.onsuccess = () => resolve(request.result || [])
+      request.onerror = () => reject(new Error('Failed to get syncing items'))
+    })
+  }
+
+  async markSyncing(highlightIds: string[]): Promise<void> {
+    if (!this.db) await this.init()
+
+    for (const id of highlightIds) {
+      const highlight = await getHighlight(id)
+      if (highlight) {
+        await updateHighlight({
+          ...highlight,
+          syncStatus: 'syncing'
+        })
+      }
+    }
+  }
+
+  async markSynced(highlightIds: string[]): Promise<void> {
+    if (!this.db) await this.init()
+
+    for (const id of highlightIds) {
+      const highlight = await getHighlight(id)
+      if (highlight) {
+        await updateHighlight({
+          ...highlight,
+          syncStatus: 'synced'
+        })
+      }
+    }
+  }
+
+  async markError(highlightIds: string[], errorMsg: string): Promise<void> {
+    if (!this.db) await this.init()
+
+    for (const id of highlightIds) {
+      const highlight = await getHighlight(id)
+      if (highlight) {
+        await updateHighlight({
+          ...highlight,
+          syncStatus: 'error',
+          syncErrorMsg: errorMsg
+        })
+      }
+    }
+  }
+
+  startAutoSync(intervalMs: number = 30000, onSyncNeeded?: () => void) {
+    this.syncInterval = setInterval(async () => {
+      const pending = await this.getPendingSyncItems()
+      if (pending.length > 0 && onSyncNeeded) {
+        onSyncNeeded()
+      }
+    }, intervalMs)
+  }
+
+  stopAutoSync() {
+    if (this.syncInterval) {
+      clearInterval(this.syncInterval)
+      this.syncInterval = null
+    }
+  }
+}