// (c) 2015 Don Coleman
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

/* global ble, statusDiv, beatsPerMinute */
/* jshint browser: true , devel: true*/

// See BLE heart rate service http://goo.gl/wKH3X7
var heartRate = {
  service: "180d",
  measurement: "2a37"
};

function stringToBytes(string) {
    var array = new Uint8Array(string.length);
    for (var i = 0, l = string.length; i < l; i++) {
        array[i] = string.charCodeAt(i);
     }
     return array.buffer;
 }

var app = {
  initialize: function() {
    this.bindEvents();
  },
  bindEvents: function() {
    document.addEventListener("deviceready", this.onDeviceReady, false);
  },
  onDeviceReady: function() {
    app.scan();
  },
  scan: function() {
    app.status("Scanning for Heart Rate Monitor");

    var found = false;

    function onScan(device) {
      // this is demo code, assume there is only one heart rate monitor
      console.log("Found " + JSON.stringify(device));
      found = true;
      if (device.name == "wifitest") {
        ble.connect(device.id, app.onConnect, app.onDisconnect);
      }
    }

    function scanFailure(reason) {
      alert("BLE Scan Failed");
    }

    ble.scan([], 5, onScan, scanFailure);

    setTimeout(function() {
      if (!found) {
        app.status("Did not find a wifi config service.");
      }
    }, 5000);
  },
  onConnect: function(peripheral) {
    app.status("Connected to " + peripheral.id);
    var data = stringToBytes("test");
    ble.write(
      peripheral.id,
      "ffffffff-ffff-ffff-ffff-fffffffffff0",
      "ffffffff-ffff-ffff-ffff-fffffffffff1",
      data,
      function() {
        console.log("success");
      },
      function(error) {
        console.log(error);
      }
    );
  },
  onDisconnect: function(reason) {
    alert("Disconnected " + reason);
    beatsPerMinute.innerHTML = "...";
    app.status("Disconnected");
  },
  onData: function(buffer) {
    // assuming heart rate measurement is Uint8 format, real code should check the flags
    // See the characteristic specs http://goo.gl/N7S5ZS
    var data = new Uint8Array(buffer);
    beatsPerMinute.innerHTML = data[1];
  },
  onError: function(reason) {
    alert("There was an error " + reason);
  },
  status: function(message) {
    console.log(message);
    statusDiv.innerHTML = message;
  }
};

app.initialize();