const { Pool }  = require('pg');

const pool = new Pool({
    user: process.env.DB_USER,
    password: process.env.DB_PSW,
    host: process.env.DB_HOST,
    port: process.env.DB_PORT,
    max: 10,
    idleTimeoutMillis: 30000,
    connectionTimeoutMillis: 5000,
})

const dbs = {
    data: { name: process.env.DATA_DB },
    sensors: { name: process.env.SENSORS_DB }
}

console.log('Database configuration:', {
    host: process.env.DB_HOST,
    port: process.env.DB_PORT,
    user: process.env.DB_USER,
    password: process.env.DB_PSW,
    database: Object.fromEntries(Object.entries(dbs).map(([k, v]) => [k, v.name]))
});

function getPool(db) {
    const dbConfig = dbs[db];
    if (!dbConfig) throw new Error(`Database ${db} not configured`);
    return new Pool({ ...pool.options, database: dbConfig.name });
}

async function checkConnection(db) {
    try {
        await getPool(db).query('SELECT NOW()');
        return true;
    } catch (err) {
        console.error(`Error connecting to ${db} database`, err);
        return false;   
    }
}

async function query(db, text, params) {
    const pool = getPool(db);
    return pool.query(text, params);
}

async function init() {
    try {
        await query('sensors', `
            CREATE TABLE IF NOT EXISTS sensors (
                id SERIAL PRIMARY KEY,
                name VARCHAR(255) UNIQUE NOT NULL,
                code_hash TEXT NOT NULL,
                created_at TIMESTAMPTZ DEFAULT NOW()
            );
        `);
    } catch (err) {
        console.error('Error creating sensors table', err);
    }
}

init();

module.exports = { checkConnection, query };