Refine property search logic and enhance fallback responses

- Updated the `extract_and_search_properties` function to improve the property search process by implementing a multi-pass filtering strategy, allowing for more flexible search results based on user preferences.
- Enhanced fallback responses to provide clearer communication when no properties match the user's criteria, including suggestions for broader searches and notifications for future availability.
- Improved logging to track the filtering process and the state of the search, aiding in debugging and user experience.

ai_chat.py

@@ -2,7 +2,7 @@ from langgraph.graph import StateGraph, END
 from langchain_core.runnables import RunnableLambda
 from typing import TypedDict
 from config import llm, OPENAI_API_KEY
-from database import get_session_messages, save_message, update_user_persona, update_user_intent, search_properties
+from database import get_session_messages, save_message, update_user_persona, update_user_intent, search_properties, end_session
 
 def chat_with_session_memory(state):
     """Chat function with session-based memory"""
@@ -272,45 +272,86 @@ async def extract_and_search_properties(state):
     intent = state.get("intent", {})
     print(f"Intent data: {intent}")
     
-    # Check if we have the minimum required fields for property search
+    # Check if we have the minimum required field for property search
     location = intent.get("location_preference")
-    budget = intent.get("budget")
-    size = intent.get("size_preference_sqm")
     
-    print(f"Location: {location}, Budget: {budget}, Size: {size}")
+    print(f"Location: {location}")
     
-    if not location or budget is None or size is None:
-        # Missing required fields, skip property search
-        print(f"Missing required fields - skipping property search")
+    if not location:
+        # Missing location, skip property search
+        print(f"Missing location - skipping property search")
         return {"response": None}
     
     # Prepare filters for property search
-    filters = {
-        "location_preference": location,
-        "budget": budget,
-        "size_preference_sqm": size,
-        "must_have": intent.get("must_have", [])
-    }
+    filters = {"location_preference": location}
+    
+    # Add budget if set
+    if intent.get("budget") is not None:
+        filters["budget"] = intent["budget"]
+    
+    # Add size if set
+    if intent.get("size_preference_sqm") is not None:
+        filters["size_preference_sqm"] = intent["size_preference_sqm"]
+    
+    # Add must-have features if set
+    must_have = intent.get("must_have", [])
+    if must_have and len(must_have) > 0:
+        filters["must_have"] = must_have
     
     print(f"Searching with filters: {filters}")
     
     # Search for properties
     properties = await search_properties(filters)
-    print(f"Found {len(properties)} properties: {properties}")
     state["properties"] = properties
     
-    if not properties:
-        # No properties found, provide fallback suggestion
-        print(f"No properties found - setting fallback message")
-        state["response"] = (
-            f"I don't have any active listings in {location} that match your criteria. "
-            "Would you like me to broaden the search to nearby areas in our database?"
-        )
-        return state
-    
-    # Properties found, continue to chat
-    print(f"Properties found - continuing to chat")
-    return {"response": None}
+    # Pass 1: strict filters
+    if properties:
+        return {"response": None}
+
+    # Pass 2: drop must-haves
+    if "must_have" in filters:
+        filters2 = {k: v for k, v in filters.items() if k != "must_have"}
+        props2 = await search_properties(filters2)
+        if props2:
+            state["properties"] = props2
+            state["response"] = (
+                "I don't have an exact match with those features, "
+                "but here are listings matching your location, budget and size."
+            )
+            return state
+
+    # Pass 3: drop size
+    if "size_preference_sqm" in filters2:
+        filters3 = {k: v for k, v in filters2.items() if k != "size_preference_sqm"}
+        props3 = await search_properties(filters3)
+        if props3:
+            state["properties"] = props3
+            state["response"] = (
+                "I don't have that exact size, "
+                "but here are listings matching your location and budget."
+            )
+            return state
+
+    # Pass 4: drop budget
+    if "budget" in filters3:
+        filters4 = {k: v for k, v in filters3.items() if k != "budget"}
+        props4 = await search_properties(filters4)
+        if props4:
+            state["properties"] = props4
+            state["response"] = (
+                f"I don't have listings within your budget in {filters4['location_preference']}, "
+                "but here are some options in that area."
+            )
+            return state
+
+    # Final fallback: no listings at all
+    state["response"] = (
+        f"I don't have any listings right now matching your criteria. "
+        "I'll notify you as soon as something becomes available. "
+        "Feel free to reach out any time!"
+    )
+    await end_session(state["session_id"])
+    return state
 
 # --- Build LangGraph ---
 graph = StateGraph(ChatState)