import asyncpg
import yaml
from typing import Optional
import logging

logger = logging.getLogger(__name__)

class DatabaseManager:
    def __init__(self):
        self.pool: Optional[asyncpg.Pool] = None
        
    async def initialize(self, config: dict):
        """Initialize database connection pool"""
        try:
            self.pool = await asyncpg.create_pool(
                host=config['host'],
                port=config['port'],
                database=config['name'],
                user=config['user'],
                password=config['password'],
                min_size=config.get('pool_min_size', 5),
                max_size=config.get('pool_max_size', 20),
                max_queries=config.get('pool_max_queries', 50000),
                max_inactive_connection_lifetime=config.get('pool_max_inactive_connection_lifetime', 300.0)
            )
            logger.info("Database pool initialized successfully")
        except Exception as e:
            logger.error(f"Failed to initialize database pool: {e}")
            raise
    
    async def close(self):
        """Close database connection pool"""
        if self.pool:
            await self.pool.close()
            logger.info("Database pool closed")
    
    async def execute_query(self, query: str, *args):
        """Execute a query and return results"""
        async with self.pool.acquire() as connection:
            return await connection.fetch(query, *args)
    
    async def execute_one(self, query: str, *args):
        """Execute a query and return single result"""
        async with self.pool.acquire() as connection:
            return await connection.fetchrow(query, *args)
    
    async def execute_command(self, query: str, *args):
        """Execute a command (INSERT, UPDATE, DELETE)"""
        async with self.pool.acquire() as connection:
            return await connection.execute(query, *args)

# Global database manager instance
db_manager = DatabaseManager()

async def get_database():
    """Dependency for getting database connection"""
    return db_manager