#!/usr/bin/env python3
"""
Migration Script: Fix Ratings and Reviews Count

This script ensures all listings and users have correct rating/reviews_count:
1. Users: Recalculates rating and reviews_count from actual reviews
2. Short-stay listings: Recalculates rating and reviews_count from actual reviews
3. Non-short-stay listings: Will use owner's rating (handled at fetch time)

Run with: python scripts/fix_ratings.py
"""

import asyncio
import sys
import os

# Add parent directory to path for imports
sys.path.insert(0, os.path.dirname(os.path.dirname(os.path.abspath(__file__))))

from motor.motor_asyncio import AsyncIOMotorClient
from bson import ObjectId
from datetime import datetime

# Import app config to get correct MongoDB URL
from app.config import settings


async def get_database():
    """Connect to MongoDB using app settings"""
    client = AsyncIOMotorClient(
        settings.MONGODB_URL,
        serverSelectionTimeoutMS=5000,
    )
    # Test connection
    await client.admin.command("ping")
    print(f"  📦 Database: {settings.MONGODB_DATABASE}")
    return client[settings.MONGODB_DATABASE]


async def recalculate_user_ratings(db):
    """
    Recalculate rating and reviews_count for all users
    based on actual reviews in the reviews collection.
    """
    print("\n" + "="*60)
    print("STEP 2: Recalculating User Ratings")
    print("="*60)

    # Get all users
    users_cursor = db.users.find({})
    users = await users_cursor.to_list(length=None)
    print(f"Found {len(users)} users to process")

    updated_count = 0

    for user in users:
        user_id = str(user["_id"])

        # Find all reviews where this user is the target
        reviews_cursor = db.reviews.find({
            "target_type": "user",
            "target_id": user_id
        })
        reviews = await reviews_cursor.to_list(length=None)

        # Calculate new rating
        if reviews:
            total_rating = sum(r.get("rating", 0) for r in reviews)
            reviews_count = len(reviews)
            avg_rating = round(total_rating / reviews_count, 2)
        else:
            reviews_count = 0
            avg_rating = 0.0

        # Get current values
        current_rating = user.get("rating", 0.0)
        current_count = user.get("reviews_count", 0)

        # Update if different or missing
        if current_rating != avg_rating or current_count != reviews_count:
            await db.users.update_one(
                {"_id": user["_id"]},
                {"$set": {
                    "rating": avg_rating,
                    "reviews_count": reviews_count
                }}
            )
            updated_count += 1
            print(f"  ✅ User {user.get('firstName', 'Unknown')} {user.get('lastName', '')}: "
                  f"{current_rating} → {avg_rating} ({reviews_count} reviews)")

    print(f"\n📊 Updated {updated_count} users")
    return updated_count


async def recalculate_listing_ratings(db):
    """
    Recalculate rating and reviews_count for all SHORT-STAY listings
    based on actual reviews in the reviews collection.

    Non-short-stay listings use the owner's rating (handled at fetch time).
    """
    print("\n" + "="*60)
    print("STEP 3: Recalculating Short-Stay Listing Ratings")
    print("="*60)

    # Get all short-stay listings
    listings_cursor = db.listings.find({"listing_type": "short-stay"})
    listings = await listings_cursor.to_list(length=None)
    print(f"Found {len(listings)} short-stay listings to process")

    updated_count = 0

    for listing in listings:
        listing_id = str(listing["_id"])

        # Find all reviews where this listing is the target
        reviews_cursor = db.reviews.find({
            "target_type": "listing",
            "target_id": listing_id
        })
        reviews = await reviews_cursor.to_list(length=None)

        # Calculate new rating
        if reviews:
            total_rating = sum(r.get("rating", 0) for r in reviews)
            reviews_count = len(reviews)
            avg_rating = round(total_rating / reviews_count, 2)
        else:
            reviews_count = 0
            avg_rating = 0.0

        # Get current values
        current_rating = listing.get("rating", 0.0)
        current_count = listing.get("reviews_count", 0)

        # Update if different or missing
        if current_rating != avg_rating or current_count != reviews_count:
            await db.listings.update_one(
                {"_id": listing["_id"]},
                {"$set": {
                    "rating": avg_rating,
                    "reviews_count": reviews_count
                }}
            )
            updated_count += 1
            print(f"  ✅ Listing '{listing.get('title', 'Untitled')[:40]}': "
                  f"{current_rating} → {avg_rating} ({reviews_count} reviews)")

    print(f"\n📊 Updated {updated_count} short-stay listings")
    return updated_count


async def ensure_fields_exist(db):
    """
    Ensure all users and listings have the rating/reviews_count fields.
    This initializes them to 0 if missing.
    """
    print("\n" + "="*60)
    print("STEP 1: Ensuring Fields Exist on All Documents")
    print("="*60)

    # Update users missing rating field
    users_result = await db.users.update_many(
        {"rating": {"$exists": False}},
        {"$set": {"rating": 0.0}}
    )
    print(f"  ✅ Added 'rating' field to {users_result.modified_count} users")

    # Update users missing reviews_count field
    users_result2 = await db.users.update_many(
        {"reviews_count": {"$exists": False}},
        {"$set": {"reviews_count": 0}}
    )
    print(f"  ✅ Added 'reviews_count' field to {users_result2.modified_count} users")

    # Update short-stay listings missing rating field
    listings_result = await db.listings.update_many(
        {"listing_type": "short-stay", "rating": {"$exists": False}},
        {"$set": {"rating": 0.0}}
    )
    print(f"  ✅ Added 'rating' field to {listings_result.modified_count} short-stay listings")

    # Update short-stay listings missing reviews_count field
    listings_result2 = await db.listings.update_many(
        {"listing_type": "short-stay", "reviews_count": {"$exists": False}},
        {"$set": {"reviews_count": 0}}
    )
    print(f"  ✅ Added 'reviews_count' field to {listings_result2.modified_count} short-stay listings")


async def print_summary(db):
    """Print a summary of the current state"""
    print("\n" + "="*60)
    print("SUMMARY")
    print("="*60)

    # Count users with reviews
    users_with_reviews = await db.users.count_documents({"reviews_count": {"$gt": 0}})
    total_users = await db.users.count_documents({})
    print(f"  👥 Users with reviews: {users_with_reviews}/{total_users}")

    # Count listings by type
    for listing_type in ["rent", "sale", "short-stay", "roommate"]:
        count = await db.listings.count_documents({"listing_type": listing_type})
        if listing_type == "short-stay":
            with_reviews = await db.listings.count_documents({
                "listing_type": listing_type,
                "reviews_count": {"$gt": 0}
            })
            print(f"  🏠 {listing_type}: {count} listings ({with_reviews} with reviews)")
        else:
            print(f"  🏠 {listing_type}: {count} listings (use owner's rating)")

    # Count total reviews
    total_reviews = await db.reviews.count_documents({})
    user_reviews = await db.reviews.count_documents({"target_type": "user"})
    listing_reviews = await db.reviews.count_documents({"target_type": "listing"})
    print(f"\n  ⭐ Total reviews: {total_reviews}")
    print(f"     - User reviews (for landlords): {user_reviews}")
    print(f"     - Listing reviews (for properties): {listing_reviews}")


async def main():
    """Main migration function"""
    print("\n" + "="*60)
    print("🔧 RATING MIGRATION SCRIPT")
    print("="*60)
    print(f"Started at: {datetime.now().strftime('%Y-%m-%d %H:%M:%S')}")

    try:
        db = await get_database()
        print(f"✅ Connected to MongoDB successfully")

        # Step 1: Ensure all fields exist
        await ensure_fields_exist(db)

        # Step 2: Recalculate user ratings
        await recalculate_user_ratings(db)

        # Step 3: Recalculate short-stay listing ratings
        await recalculate_listing_ratings(db)

        # Print summary
        await print_summary(db)

        print("\n" + "="*60)
        print("✅ MIGRATION COMPLETED SUCCESSFULLY")
        print("="*60)
        print(f"Finished at: {datetime.now().strftime('%Y-%m-%d %H:%M:%S')}")

    except Exception as e:
        print(f"\n❌ ERROR: {e}")
        import traceback
        traceback.print_exc()
        sys.exit(1)


if __name__ == "__main__":
    asyncio.run(main())