//----------------------------------------
//handler.js
//----------------------------------------
import mysql from 'mysql2/promise';
import db_config from './db_config.json';
import { success, failure } from './libs/response-lib';

export const main = (event, context, callback) => {
    console.log('start');

    const pool  = mysql.createPool({
                    host     : db_config.dbendpoint,
                    user     : db_config.dbuser,
                    password : db_config.dbpwd,
                    database : db_config.dbname
                });
    const locationid = event.locationid;
    const parameter = event.parameter;
    //proof both event.* and db_config.* are working
    console.log(parameter + " and " + db_config.dbport);

    //prevent timeout from waiting event loop
    context.callbackWaitsForEmptyEventLoop = false;

    const resPromise = pool.getConnection()
        .then((connection) => {
            console.log("got connection");
            // Use the connection
            const res  = connection.execute(
            'SELECT * FROM radar_pubweb r WHERE r.locationid = ? AND r.parameter = ?',
            [locationid, parameter]);

            // And done with the connection.
            connection.release();
            return res;
        }).then((result) => {
            console.log(result);
            return result;
        }).catch((err) => {
            // And done with the connection.
            console.log('error : ', err);
            throw err;
        })

    console.log("end");
    return resPromise;
}

//----------------------------------------
//response-lib.js
//----------------------------------------
function buildResponse(statusCode, body) {
  return {
    statusCode,
    headers: {
      'Access-Control-Allow-Origin': '*',
      'Access-Control-Allow-Credentials': true,
    },
    body: JSON.stringify(body),
  };
}
export function internalError(err) {
  return buildResponse(500, { message: err.message, type: 'internalError' });
}

export function success(body) {
  return buildResponse(200, body);
}

export function failure(body) {
  return buildResponse(500, body);
}

export function notFound(obj) {
  return buildResponse(404, { message: `The object ${obj} is not found`, type: 'notFound' });
}