const db = require('../config/db');
const { logger } = require('../util/logger');

async function total_users(from_date, to_date) {
  try {
    const result = await db.query(
      `SELECT * FROM users WHERE created_at BETWEEN $1 AND $2`,
      [from_date, to_date]
    );
    logger.info("data fetch for users");
    return result.rows;
  } catch (err) {
    logger.error(err, 'failed to fetch data');
    res.status(500).json({ error: 'something went wrong' });
  }
}

async function getTransactions(filters) {
  try {
    const { trx_type, from_date, to_date, client, amount_min, amount_max, customer_no } = filters;

    let query = `SELECT * FROM transactions WHERE trx_type = $1 AND created_at >= $2 AND created_at < $3`;
    const params = [trx_type, from_date, to_date];
    let paramIndex = 4;

    if (client) {
      query += ` AND client = $${paramIndex++}`;
      params.push(client);
    }

    if (amount_min && amount_max) {
      query += ` AND amount BETWEEN $${paramIndex++} AND $${paramIndex++}`;
      params.push(amount_min, amount_max);
    } else if (amount_min) {
      query += ` AND amount >= $${paramIndex++}`;
      params.push(amount_min);
    } else if (amount_max) {
      query += ` AND amount <= $${paramIndex++}`;
      params.push(amount_max);
    }

    if (customer_no) {
      query += ` AND customer_no = $${paramIndex++}`;
      params.push(customer_no);
    }

    query += ` ORDER BY created_at DESC`;

    const result = await db.query(query, params);
    logger.info(`Fetched ${result.rows.length} transactions`);
    return result.rows;

  } catch (err) {
    logger.error(err, 'failed to fetch transactions');
    throw err;
  }
}

async function getFailedTransactions(filters) {
  try {
    const { from_date, to_date, customer_no } = filters;

    let query = `
      SELECT * 
      FROM transactions 
      WHERE created_at >= $1 
        AND created_at < $2 
        AND status LIKE 'FAILURE%'`;

    // params should match $1, $2, etc.
    const params = [from_date, to_date];
    let paramIndex = params.length + 1; // start from 3

    if (customer_no) {
      query += ` AND customer_no = $${paramIndex}`;
      params.push(customer_no);
    }

    query += ` ORDER BY created_at DESC`;
    console.log(query);

    const result = await db.query(query, params);
    logger.info(`Fetched ${result.rows.length} failed transactions`);
    return result.rows;

  } catch (err) {
    logger.error(err, 'Failed to fetch failed transactions');
    throw err;
  }
}

async function getNotLogin(duration) {
  try {
    const result = await db.query(
      `SELECT * FROM users WHERE last_login <= NOW() - ($1 || ' month')::interval`,
      [duration]
    );
    logger.info("data fetch for users who have not logged-in in mentioned duration");
    return result.rows;
  } catch (err) {
    logger.error(err, 'failed to fetch not logged-in users data');
    res.status(500).json({ error: 'something went wrong' });
  }
}

module.exports = { total_users, getTransactions, getFailedTransactions, getNotLogin };