/**
 *
 * User: Martin Donnelly
 * Date: 2016-07-06
 * Time: 13:37
 *
 */

var cp = require('child_process');
var spawn = cp.spawn;
var fork = cp.fork;
var spawnP = require('child-process-promise').spawn;

var EventEmitter = require('events');
var busEmitter = new EventEmitter();

var util = require('util');

var logger = require('log4js').getLogger();

var bluetest;
bluetest = module.exports = function(options) {
  'use strict';

  var core = {
    mac: '', gatt: null
  };

  core.processLuxData = function(data) {
    var m, e, lux;
    var _data = data.toString();
    logger.debug(data);
    logger.debug(_data);
    var wH = _data.slice(-5).split(' ');
    var wB = [];
    wB[0] = parseInt(wH[0], 16);
    wB[1] = parseInt(wH[1], 16);
    logger.debug(wH);
    logger.debug(wB);

    var word = (wB[1] << 16) + wB[0];

    var raw = new Uint16Array(1);
    raw[0] = word;

    logger.debug(word);

    m = raw & 0x0FFF;
    e = (raw & 0xF000) >> 12;

    lux = m * (0.01 * Math.pow(2.0, e));

    logger.info('Lux: ', lux);

  };

  core.enableLuxNotification = function() {
    logger.info('Enable Luxomity Notifications...');
    core.gatt.stdin.write('char-write-req 0x0042 0100\n');
    core.gatt.stdin.write('char-write-req 0x0044 01\n');
  };

  core.gattConnected = function() {
    logger.debug('Gatt connected!!!!!');

    core.enableLuxNotification();
    // Core.gatt.stdin.write('primary\n');
  };

  core.connectGatt = function() {
    logger.info('trying to connect using gatttool');
    core.gatt = spawn('gatttool', ['-I']);
    var cStr;
    core.gatt.on('error', function(err) {
      logger.error(err);
    });
    core.gatt.on('exit', function(code) {

      logger.debug('gatt exit code', code);
    });

    core.gatt.on('message', function(m) {
      logger.info(m);
    });

    core.gatt.stdout.on('data', (data) => {

      logger.info(`stdout: ${data}`);

      if (data.indexOf('Connection successful') > -1) {

        busEmitter.emit('connected');
      }

      if (data.indexOf('Notification handle = 0x0041') > -1) {
        busEmitter.emit('processLux', data);
      }

    });

    core.gatt.stderr.on('data', (data) => {
      logger.info(`stderr: ${data}`);
    });

    core.gatt.on('close', (code) => {
      logger.warn(`child process exited with code ${code}`);
    });

    logger.info('Trying to connect to ', core.mac);
    cStr = 'connect ' + core.mac + '\n';
    core.gatt.stdin.write(cStr);

  };

  core.init = function(options) {

    var tool_path = '';
    var hcidev = 'hvi0';

    if (typeof options.mac !== 'undefined') {
      core.mac = options.mac;
    }
    else {
      console.log('You need to pass a mac address.');
      process.exit(1);
    }
    logger.info('Working with:', options);

    var hciconfig = spawn(tool_path + 'hciconfig', [hcidev, 'up']);

    hciconfig.on('exit', function(code) {

      logger.debug('code', code);

      if (code !== 0) {

        // Could not get the device UP, maybe due to permissions, should run with sudo.
        busEmitter.emit('error',
          'hciconfig: failed to bring up device ' + hcidev + '. Try running with sudo.');
        return;

      }
      else {

        core.connectGatt();

      }

    });

  };

  busEmitter.on('connected', core.gattConnected);
  busEmitter.on('processLux', core.processLuxData);
  core.init(options);
};
util.inherits(bluetest, EventEmitter);