from datetime import datetime, timedelta
from config import supabase

async def get_or_create_user(wa_id: str, name: str = None) -> dict:
    """Get existing user or create new one"""
    if not supabase:
        return {"wa_id": wa_id, "name": name or "Unknown"}
    
    try:
        # Try to get existing user
        response = supabase.table("users").select("*").eq("wa_id", wa_id).execute()
        
        if response.data:
            # User exists, update if name provided
            user = response.data[0]
            if name and name != user.get("name"):
                supabase.table("users").update({"name": name, "updated_at": datetime.utcnow().isoformat()}).eq("wa_id", wa_id).execute()
                user["name"] = name
            return user
        else:
            # Create new user
            new_user = {
                "wa_id": wa_id,
                "name": name or "Unknown",
                "created_at": datetime.utcnow().isoformat(),
                "updated_at": datetime.utcnow().isoformat()
            }
            response = supabase.table("users").insert(new_user).execute()
            return response.data[0] if response.data else new_user
            
    except Exception as e:
        print(f"Error in get_or_create_user: {e}")
        return {"wa_id": wa_id, "name": name or "Unknown"}

async def update_user_activity(wa_id: str):
    """Update user's last activity timestamp"""
    if not supabase:
        return
    
    try:
        supabase.table("users").update({"updated_at": datetime.utcnow().isoformat()}).eq("wa_id", wa_id).execute()
    except Exception as e:
        print(f"Error updating user activity: {e}")

# --- Session Management ---
async def get_active_session(wa_id: str) -> dict:
    """Get the active session for a user (not ended and within 3 hours)"""
    if not supabase:
        return None
    
    try:
        # Calculate 3 hours ago
        three_hours_ago = datetime.utcnow() - timedelta(hours=3)
        
        response = supabase.table("chat_sessions").select("*").eq("wa_id", wa_id).eq("ended", False).gte("last_activity", three_hours_ago.isoformat()).order("last_activity", desc=True).limit(1).execute()
        
        return response.data[0] if response.data else None
    except Exception as e:
        print(f"Error getting active session: {e}")
        return None

async def create_new_session(wa_id: str) -> dict:
    """Create a new chat session for a user"""
    if not supabase:
        return {"id": "local_session", "wa_id": wa_id, "started_at": datetime.utcnow().isoformat(), "last_activity": datetime.utcnow().isoformat(), "ended": False}
    
    try:
        new_session = {
            "wa_id": wa_id,
            "started_at": datetime.utcnow().isoformat(),
            "last_activity": datetime.utcnow().isoformat(),
            "ended": False
        }
        response = supabase.table("chat_sessions").insert(new_session).execute()
        return response.data[0] if response.data else new_session
    except Exception as e:
        print(f"Error creating new session: {e}")
        return {"id": "local_session", "wa_id": wa_id, "started_at": datetime.utcnow().isoformat(), "last_activity": datetime.utcnow().isoformat(), "ended": False}

async def update_session_activity(session_id: str):
    """Update session's last activity timestamp"""
    if not supabase or session_id == "local_session":
        return
    
    try:
        supabase.table("chat_sessions").update({"last_activity": datetime.utcnow().isoformat()}).eq("id", session_id).execute()
    except Exception as e:
        print(f"Error updating session activity: {e}")

async def end_session(session_id: str):
    """Mark a session as ended"""
    if not supabase or session_id == "local_session":
        return
    
    try:
        supabase.table("chat_sessions").update({"ended": True}).eq("id", session_id).execute()
    except Exception as e:
        print(f"Error ending session: {e}")

# --- Message Management ---
async def save_message(session_id: str, wa_id: str, wamid: str, role: str, content: str):
    """Save a message to the database"""
    if not supabase or session_id == "local_session":
        return
    
    try:
        message = {
            "session_id": session_id,
            "wa_id": wa_id,
            "wamid": wamid,
            "role": role,
            "content": content,
            "created_at": datetime.utcnow().isoformat()
        }
        supabase.table("messages").insert(message).execute()
    except Exception as e:
        print(f"Error saving message: {e}")

async def get_session_messages(session_id: str, limit: int = 10) -> list:
    """Get recent messages for a session (for memory context)"""
    if not supabase or session_id == "local_session":
        return []
    
    try:
        response = supabase.table("messages").select("*").eq("session_id", session_id).order("created_at", desc=True).limit(limit).execute()
        # Reverse to get chronological order
        messages = response.data[::-1] if response.data else []
        return messages
    except Exception as e:
        print(f"Error getting session messages: {e}")
        return []

# --- Session Management Helper ---
async def get_or_create_active_session(wa_id: str) -> dict:
    """Get active session or create new one if needed"""
    active_session = await get_active_session(wa_id)
    
    if active_session:
        # Update activity
        await update_session_activity(active_session["id"])
        return active_session
    else:
        # Create new session
        return await create_new_session(wa_id)

async def get_user(wa_id: str):
    """Get user by WhatsApp ID"""
    if not supabase:
        return None
    
    try:
        response = supabase.table("users").select("*").eq("wa_id", wa_id).execute()
        return response.data[0] if response.data else None
    except Exception as e:
        print(f"Error getting user: {e}")
        return None

async def list_users(limit: int = 50, offset: int = 0):
    """List all users with pagination"""
    if not supabase:
        return {"users": [], "count": 0}
    
    try:
        response = supabase.table("users").select("*").range(offset, offset + limit - 1).order("created_at", desc=True).execute()
        return {"users": response.data, "count": len(response.data)}
    except Exception as e:
        print(f"Error listing users: {e}")
        return {"users": [], "count": 0}

async def update_user_name(wa_id: str, name: str):
    """Update user name"""
    if not supabase:
        return None
    
    try:
        response = supabase.table("users").update({
            "name": name,
            "updated_at": datetime.utcnow().isoformat()
        }).eq("wa_id", wa_id).execute()
        
        return response.data[0] if response.data else None
    except Exception as e:
        print(f"Error updating user: {e}")
        return None

# --- Persona Management ---
async def get_user_persona(wa_id: str) -> dict:
    """
    Fetch the persona row for this user.
    Returns an empty dict if no data exists.
    """
    if not supabase:
        return {}
    
    try:
        resp = supabase\
            .table("user_personas")\
            .select("*")\
            .eq("wa_id", wa_id)\
            .single()\
            .execute()
        return resp.data or {}
    except Exception as e:
        print(f"Error getting user persona: {e}")
        return {}

async def update_user_persona(wa_id: str, updates: dict):
    """
    Apply partial updates to the persona row.
    Automatically sets `updated_at` to now().
    """
    if not supabase:
        return
    
    try:
        updates_with_ts = {**updates, "updated_at": datetime.utcnow().isoformat()}
        
        # First try to get existing persona
        existing = supabase.table("user_personas").select("*").eq("wa_id", wa_id).execute()
        
        if existing.data:
            # Update existing record
            supabase\
                .table("user_personas")\
                .update(updates_with_ts)\
                .eq("wa_id", wa_id)\
                .execute()
        else:
            # Create new record
            new_persona = {
                "wa_id": wa_id,
                "created_at": datetime.utcnow().isoformat(),
                **updates_with_ts
            }
            supabase.table("user_personas").insert(new_persona).execute()
            
    except Exception as e:
        print(f"Error updating user persona: {e}")

# --- Intent Management ---
async def get_or_create_user_intent(session_id: str, wa_id: str) -> dict:
    """
    Fetch or create the intent record for this session.
    """
    resp = supabase \
        .table("user_intents") \
        .select("*") \
        .eq("session_id", session_id) \
        .single() \
        .execute()
    if resp.data:
        return resp.data
    new_intent = {
        "session_id":          session_id,
        "wa_id":               wa_id,
        "location_preference": None,
        "budget":              None,
        "size_preference_sqm": None,
        "must_have":           None,
        "created_at":          datetime.utcnow().isoformat(),
        "updated_at":          datetime.utcnow().isoformat()
    }
    insert = supabase.table("user_intents").insert(new_intent).execute()
    return insert.data[0] if insert.data else new_intent

async def update_user_intent(session_id: str, updates: dict):
    """
    Patch the intent record with any changed fields.
    """
    updates_with_ts = { **updates, "updated_at": datetime.utcnow().isoformat() }
    supabase \
        .table("user_intents") \
        .update(updates_with_ts) \
        .eq("session_id", session_id) \
        .execute()