const mysql = require('mysql2/promise');
const path = require('path');
require('dotenv').config({ path: path.resolve(__dirname, '../../..', '.env') });

// Database configuration
const dbConfig = {
    host: process.env.DB_HOST,
    user: process.env.DB_USER,
    password: process.env.DB_PASSWORD,
    database: process.env.DB_NAME,
    waitForConnections: true,
    connectionLimit: 10,
    queueLimit: 0,
    // Add performance optimizations
    namedPlaceholders: true,
    maxPreparedStatements: 256,
    enableKeepAlive: true,
    keepAliveInitialDelay: 0,
    // Add memory optimizations
    flags: [
        'FOUND_ROWS',
        'LONG_PASSWORD',
        'PROTOCOL_41',
        'TRANSACTIONS',
        'SECURE_CONNECTION',
        'MULTI_RESULTS',
        'PS_MULTI_RESULTS',
        'PLUGIN_AUTH',
        'CONNECT_ATTRS',
        'PLUGIN_AUTH_LENENC_CLIENT_DATA',
        'SESSION_TRACK',
        'MULTI_STATEMENTS'
    ]
};

// Create a single pool instance to be reused
const pool = mysql.createPool(dbConfig);

async function getConnection() {
    return await pool.getConnection();
}

async function closePool() {
    await pool.end();
}

module.exports = {
    dbConfig,
    getConnection,
    closePool
};