feat: Implement product detail syncing with rowversion-based change detection and integrate it into category product synchronization.

src/syncers/product-detail-syncer.js

@@ -0,0 +1,120 @@
+import fs from 'fs/promises';
+import path from 'path';
+import { SyncQueueManager } from '../utils/sync-queue-manager.js';
+import { ProductDetailDataFetcher } from '../services/product-detail-data-fetcher.js';
+import { getExistingIds, deleteObsoleteFiles, ensureDir, writeJsonIfChanged } from '../utils/file-sync-utils.js';
+
+class ProductDetailSyncer {
+    constructor() {
+        if (ProductDetailSyncer.instance) {
+            return ProductDetailSyncer.instance;
+        }
+
+        this.syncQueue = new SyncQueueManager();
+        this.dataFetcher = new ProductDetailDataFetcher();
+        this.cacheBaseDir = process.env.CACHE_LOCATION || '.';
+
+        ProductDetailSyncer.instance = this;
+    }
+
+    async syncDetails(articleIds) {
+        await this.syncQueue.executeSync('product-details', async () => {
+            await this._performSync(articleIds);
+        }, articleIds);
+    }
+
+    async _performSync(articleIds) {
+        const detailsDir = path.join(this.cacheBaseDir, 'details');
+        const stateFile = path.join(this.cacheBaseDir, 'product-details-state.json');
+
+        // Ensure directory exists
+        await ensureDir(detailsDir);
+
+        // Load state
+        let lastSyncRowversion = null;
+        try {
+            const state = JSON.parse(await fs.readFile(stateFile, 'utf-8'));
+            lastSyncRowversion = state.lastSyncRowversion;
+        } catch (err) {
+            // State file might not exist yet
+        }
+
+        // Get existing files
+        const existingIds = await getExistingIds(detailsDir, {
+            suffix: '.json'
+        });
+
+        const validIds = new Set(articleIds.filter(id => id !== null && id !== undefined));
+
+        // Delete obsolete files
+        await deleteObsoleteFiles(
+            detailsDir,
+            existingIds,
+            validIds,
+            (id) => `${id}.json`
+        );
+
+        // Split into missing and present
+        const missingIds = [];
+        const presentIds = [];
+
+        for (const id of validIds) {
+            if (existingIds.includes(id)) {
+                presentIds.push(id);
+            } else {
+                missingIds.push(id);
+            }
+        }
+
+        // Determine what to fetch
+        const toFetch = new Set(missingIds);
+
+        if (presentIds.length > 0) {
+            // Check which present files need update based on rowversion
+            //console.log(`Checking changes for ${presentIds.length} present items with lastSyncRowversion: ${lastSyncRowversion}`);
+            const changedIds = await this.dataFetcher.fetchChangedArticleIds(presentIds, lastSyncRowversion);
+            //console.log(`Got ${changedIds.size} changed items from fetcher`);
+            changedIds.forEach(id => toFetch.add(id));
+        }
+
+        if (toFetch.size > 0) {
+            console.log(`📝 Syncing ${toFetch.size} product details (Missing: ${missingIds.length}, Changed: ${toFetch.size - missingIds.length})...`);
+            await this._fetchAndWriteDetails([...toFetch], detailsDir, stateFile, lastSyncRowversion);
+        } else {
+            //console.log(`✅ No product details to sync.`);
+        }
+    }
+
+    async _fetchAndWriteDetails(ids, dir, stateFile, currentMaxRowversion) {
+        let maxRowversion = currentMaxRowversion;
+
+        await this.dataFetcher.fetchDetailsInChunks(ids, async (record) => {
+            const filePath = path.join(dir, `${record.kArtikel}.json`);
+
+            // Update max rowversion
+            if (record.bRowversion) {
+                // Simple string comparison for hex strings works for sorting/max if length is same.
+                // MSSQL rowversions are fixed length (8 bytes), so hex string length should be constant.
+                if (!maxRowversion || record.bRowversion > maxRowversion) {
+                    maxRowversion = record.bRowversion;
+                }
+            }
+
+            // Use writeJsonIfChanged which handles reading and comparing
+            // It will compare the new object with the existing JSON content
+            await writeJsonIfChanged(filePath, {
+                kArtikel: record.kArtikel,
+                cBeschreibung: record.cBeschreibung || null, // Ensure null is written if missing
+                bRowversion: record.bRowversion || null
+            });
+        });
+
+        // Save new state
+        if (maxRowversion && maxRowversion !== currentMaxRowversion) {
+            await fs.writeFile(stateFile, JSON.stringify({ lastSyncRowversion: maxRowversion }, null, 2));
+        }
+    }
+}
+
+const instance = new ProductDetailSyncer();
+export default instance;