update error

backend/services/dashboard_service.py

@@ -0,0 +1,63 @@
+from datetime import datetime, timedelta
+from typing import Dict, List, Optional
+import logging
+
+logger = logging.getLogger(__name__)
+
+class DashboardService:
+    def __init__(self, db):
+        self.db = db
+    
+    async def calculate_user_rank(self, user_id: str) -> int:
+        """Calculate user's global rank based on total points"""
+        try:
+            user_stats = self.db.user_stats.find_one({"user_id": user_id})
+            user_points = user_stats.get("total_points", 0) if user_stats else 0
+            
+            # Count users with higher points
+            higher_ranked = self.db.user_stats.count_documents({
+                "total_points": {"$gt": user_points}
+            })
+            
+            return higher_ranked + 1
+            
+        except Exception as e:
+            logger.error(f"Error calculating user rank: {e}")
+            return 999
+    
+    async def update_user_points(self, user_id: str, points_to_add: int, activity_type: str):
+        """Add points to user's total and update rank"""
+        try:
+            # Update user stats
+            self.db.user_stats.update_one(
+                {"user_id": user_id},
+                {
+                    "$inc": {"total_points": points_to_add},
+                    "$set": {"last_updated": datetime.now()}
+                },
+                upsert=True
+            )
+            
+            # Recalculate rank
+            new_rank = await self.calculate_user_rank(user_id)
+            self.db.user_stats.update_one(
+                {"user_id": user_id},
+                {"$set": {"rank": new_rank}}
+            )
+            
+            logger.info(f"Added {points_to_add} points to user {user_id} for {activity_type}")
+            
+        except Exception as e:
+            logger.error(f"Error updating user points: {e}")
+    
+    def get_leaderboard(self, limit: int = 100) -> List[Dict]:
+        """Get global leaderboard"""
+        try:
+            return list(self.db.user_stats.find(
+                {},
+                {"user_id": 1, "total_points": 1, "rank": 1}
+            ).sort("total_points", -1).limit(limit))
+            
+        except Exception as e:
+            logger.error(f"Error fetching leaderboard: {e}")
+            return []