const { Pool } = require('pg');
const { DATABASE_URL } = require('./config');

const pool = new Pool({
    connectionString: DATABASE_URL
});

const initDB = async () => {
    try {
        await pool.query(`
            CREATE TABLE IF NOT EXISTS orders (
                id SERIAL PRIMARY KEY,
                cliente_nome VARCHAR(255),
                data_pedido VARCHAR(50),
                valor_pedido NUMERIC(10, 2),
                produto_id VARCHAR(100),
                produto_descricao TEXT,
                quantidade INTEGER,
                valor_unitario NUMERIC(10, 5),
                created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP
            );
        `);

        await pool.query(`ALTER TABLE orders ADD COLUMN IF NOT EXISTS pedido_id VARCHAR(100);`).catch(() => {});
        await pool.query(`ALTER TABLE orders ADD COLUMN IF NOT EXISTS cliente_fone VARCHAR(50);`).catch(() => {});

        await pool.query(`CREATE UNIQUE INDEX IF NOT EXISTS unique_order_product ON orders (pedido_id, produto_id);`).catch(err => {
            console.error('Notice: Could not create unique index (might already exist or there are duplicates):', err.message);
        });

        await pool.query(`
            CREATE TABLE IF NOT EXISTS stock (
                produto_id VARCHAR(100) PRIMARY KEY,
                nome TEXT,
                saldo INTEGER DEFAULT 0,
                delta_estoque INTEGER DEFAULT 0,
                updated_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP
            );
        `);

        await pool.query(`
            CREATE TABLE IF NOT EXISTS stock_campaign_queue (
                id SERIAL PRIMARY KEY,
                base_product_name TEXT NOT NULL,
                produto_id VARCHAR(100) NOT NULL,
                nome TEXT NOT NULL,
                saldo INTEGER DEFAULT 0,
                delta_estoque INTEGER DEFAULT 0,
                status VARCHAR(20) DEFAULT 'pending',
                attempts INTEGER DEFAULT 0,
                last_error TEXT,
                created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
                updated_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
                sent_at TIMESTAMP
            );
        `);

        await pool.query(`CREATE INDEX IF NOT EXISTS idx_stock_campaign_queue_status ON stock_campaign_queue (status);`);
        await pool.query(`CREATE INDEX IF NOT EXISTS idx_orders_cliente_fone ON orders (cliente_fone);`);
        await pool.query(`CREATE INDEX IF NOT EXISTS idx_orders_produto_id ON orders (produto_id);`);

        console.log('Database initialized successfully.');
    } catch (err) {
        console.error('Failed to initialize database:', err);
        throw err;
    }
};

module.exports = {
    pool,
    initDB
};