Add: Sync diagnostics endpoint for troubleshooting contact linking

app/system/backend/sync_router.py

@@ -523,3 +523,91 @@ async def sync_cvr_to_economic() -> Dict[str, Any]:
     except Exception as e:
         logger.error(f"❌ CVR to e-conomic sync error: {e}")
         raise HTTPException(status_code=500, detail=str(e))
+
+
+@router.get("/sync/diagnostics")
+async def sync_diagnostics() -> Dict[str, Any]:
+    """
+    Diagnostics: Check contact linking coverage
+    Shows why contacts aren't linking to customers
+    """
+    try:
+        logger.info("🔍 Running sync diagnostics...")
+        
+        # Check Hub data
+        hub_stats = execute_query("""
+            SELECT 
+                COUNT(*) as total_customers,
+                COUNT(vtiger_id) as customers_with_vtiger
+            FROM customers
+        """)
+        
+        vtiger_ids_in_hub = execute_query(
+            "SELECT vtiger_id FROM customers WHERE vtiger_id IS NOT NULL"
+        )
+        hub_vtiger_set = set(row['vtiger_id'] for row in vtiger_ids_in_hub)
+        
+        contact_stats = execute_query("""
+            SELECT 
+                COUNT(*) as total_contacts,
+                COUNT(vtiger_id) as contacts_with_vtiger
+            FROM contacts
+        """)
+        
+        link_stats = execute_query("""
+            SELECT COUNT(*) as total_links
+            FROM contact_companies
+        """)
+        
+        # Fetch sample contacts from vTiger
+        vtiger = get_vtiger_service()
+        query = "SELECT id, firstname, lastname, account_id FROM Contacts ORDER BY id LIMIT 200;"
+        contacts = await vtiger.query(query)
+        
+        # Analyze
+        with_account = [c for c in contacts if c.get('account_id')]
+        account_ids = set(c['account_id'] for c in with_account)
+        
+        matched_accounts = [aid for aid in account_ids if aid in hub_vtiger_set]
+        unmatched_accounts = [aid for aid in account_ids if aid not in hub_vtiger_set]
+        
+        result = {
+            "hub": {
+                "total_customers": hub_stats[0]['total_customers'],
+                "customers_with_vtiger_id": hub_stats[0]['customers_with_vtiger'],
+                "unique_vtiger_ids": len(hub_vtiger_set),
+                "total_contacts": contact_stats[0]['total_contacts'],
+                "contacts_with_vtiger_id": contact_stats[0]['contacts_with_vtiger'],
+                "total_links": link_stats[0]['total_links']
+            },
+            "vtiger_sample": {
+                "sample_size": len(contacts),
+                "contacts_with_account_id": len(with_account),
+                "unique_account_ids": len(account_ids),
+                "account_ids_found_in_hub": len(matched_accounts),
+                "account_ids_missing_in_hub": len(unmatched_accounts),
+                "match_rate_percent": round((len(matched_accounts) / len(account_ids) * 100), 1) if account_ids else 0
+            },
+            "examples": {
+                "matched_account_ids": matched_accounts[:5],
+                "unmatched_account_ids": unmatched_accounts[:10]
+            },
+            "recommendation": ""
+        }
+        
+        # Add recommendation
+        match_rate = result['vtiger_sample']['match_rate_percent']
+        if match_rate < 50:
+            result['recommendation'] = f"⚠️ LOW MATCH RATE ({match_rate}%) - Kør først /sync/vtiger for at linke flere accounts"
+        elif match_rate < 90:
+            result['recommendation'] = f"⚡ MEDIUM MATCH RATE ({match_rate}%) - Nogen accounts mangler stadig at blive linket"
+        else:
+            result['recommendation'] = f"✅ HIGH MATCH RATE ({match_rate}%) - De fleste contacts kan linkes"
+        
+        logger.info(f"✅ Diagnostics complete: {result['recommendation']}")
+        
+        return result
+        
+    except Exception as e:
+        logger.error(f"❌ Diagnostics error: {e}", exc_info=True)
+        raise HTTPException(status_code=500, detail=str(e))