"""
Migration: Add web authentication support to players table

Adds:
- username column (unique, nullable for existing Telegram-only accounts)
- password_hash column (nullable for Telegram-only accounts)
- id auto-increment column for web users (telegram_id becomes nullable)

Run this migration before starting the API service.
"""

import asyncio
import os
from sqlalchemy.ext.asyncio import create_async_engine
from sqlalchemy import text

DB_USER = os.getenv("POSTGRES_USER")
DB_PASS = os.getenv("POSTGRES_PASSWORD")
DB_NAME = os.getenv("POSTGRES_DB")
DB_HOST = os.getenv("POSTGRES_HOST", "localhost")
DB_PORT = os.getenv("POSTGRES_PORT", "5432")

DATABASE_URL = f"postgresql+psycopg://{DB_USER}:{DB_PASS}@{DB_HOST}:{DB_PORT}/{DB_NAME}"


async def migrate():
    engine = create_async_engine(DATABASE_URL)
    
    async with engine.begin() as conn:
        print("Starting migration: Add web authentication support...")
        
        # Check if columns already exist
        result = await conn.execute(text("""
            SELECT column_name 
            FROM information_schema.columns 
            WHERE table_name='players' AND column_name IN ('id', 'username', 'password_hash')
        """))
        existing_columns = {row[0] for row in result}
        
        if 'id' not in existing_columns:
            print("Adding id column...")
            await conn.execute(text("""
                ALTER TABLE players 
                ADD COLUMN id SERIAL UNIQUE
            """))
        else:
            print("✓ id column already exists")
        
        if 'username' not in existing_columns:
            print("Adding username column...")
            await conn.execute(text("""
                ALTER TABLE players 
                ADD COLUMN username VARCHAR(50) UNIQUE
            """))
        else:
            print("✓ username column already exists")
        
        if 'password_hash' not in existing_columns:
            print("Adding password_hash column...")
            await conn.execute(text("""
                ALTER TABLE players 
                ADD COLUMN password_hash VARCHAR(255)
            """))
        else:
            print("✓ password_hash column already exists")
        
        # Note: telegram_id stays as primary key for backwards compatibility
        # Web users will use the 'id' column instead
        print("✓ Keeping telegram_id as primary key for Telegram users")
        
        # Add constraint: either telegram_id or username must be present
        print("Adding check constraint...")
        try:
            await conn.execute(text("""
                ALTER TABLE players 
                ADD CONSTRAINT players_auth_check 
                CHECK (telegram_id IS NOT NULL OR username IS NOT NULL)
            """))
            print("✓ Check constraint added")
        except Exception as e:
            if "already exists" in str(e):
                print("✓ Check constraint already exists")
            else:
                raise
        
        print("\n✅ Migration completed successfully!")
        print("\nNote: Telegram users will continue to use telegram_id as primary key")
        print("      Web users will use the auto-incrementing id column")
    
    await engine.dispose()


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