import mysql.connector
from mysql.connector import pooling
import os
from typing import List, Dict, Any, Optional

# Database configuration (using environment variables for production)
DB_CONFIG = {
    "host": os.getenv("DB_HOST", "127.0.0.1"),
    "user": os.getenv("DB_USER", "radionica"),
    "password": os.getenv("DB_PASS", "NY9B9VLifDC9ehZ"),
    "database": os.getenv("DB_NAME", "radionica3d"),
    "port": int(os.getenv("DB_PORT", 3306))
}

# Connection pool
try:
    connection_pool = pooling.MySQLConnectionPool(
        pool_name="radionica_pool",
        pool_size=10,
        pool_reset_session=True,
        **DB_CONFIG
    )
    print("Database connection pool created successfully")
except mysql.connector.Error as err:
    print(f"Error creating connection pool: {err}")
    connection_pool = None

def get_connection():
    """Get a connection from the pool"""
    if connection_pool:
        return connection_pool.get_connection()
    return mysql.connector.connect(**DB_CONFIG)

def execute_query(query: str, params: tuple = ()) -> List[Dict[str, Any]]:
    """Execute a SELECT query and return results as a list of dictionaries"""
    conn = get_connection()
    cursor = conn.cursor(dictionary=True)
    try:
        cursor.execute(query, params)
        result = cursor.fetchall()
        return result
    finally:
        cursor.close()
        conn.close()

def execute_commit(query: str, params: tuple = ()) -> int:
    """Execute an INSERT/UPDATE/DELETE query and return the last inserted ID"""
    conn = get_connection()
    cursor = conn.cursor()
    try:
        cursor.execute(query, params)
        conn.commit()
        return cursor.lastrowid
    finally:
        cursor.close()
        conn.close()

def execute_batch(query: str, params_list: List[tuple]):
    """Execute multiple queries in a single transaction"""
    conn = get_connection()
    cursor = conn.cursor()
    try:
        cursor.executemany(query, params_list)
        conn.commit()
    finally:
        cursor.close()
        conn.close()