var device_QHC_UUID = '0000ffb0-0000-1000-8000-00805f9b34fb'  // 蓝牙电子秤uuid
var weighing_scale_type = '0BFF2608AC01' // 体重秤id
var weighing_scale_close = 'ac01fe010000cccb'// 体重秤灯熄灭
var weighing_scale_measure_end = 'ca'// 体重秤灯熄灭
var devList = []
var notOpenBle = false

function openBluetoothAdapter(success,fail) {

  getBLEData(success, fail)
  wx.onBluetoothAdapterStateChange(function (res) {
    // callback
    if (res.available == false) {
      notOpenBle = true
      fail('设备链接已断开')
    } else {
      console.log('蓝牙连接开启')
      if(notOpenBle){
        getBLEData(success, fail)
      }
    }
  })
}

function getBLEData(success, fail) {
  wx.openBluetoothAdapter({
    success: function (res) {
      // success
      notOpenBle = false
      wx.getBluetoothAdapterState({
        success: function (res) {
          console.log('蓝牙适配器状态', res)
          if (res.discovering == true){
            console.log('正在搜索')
            findingDevice(0, function (dev) {
              success(dev)
            })
          } else {
            searchDevice(success, fail)
          }
        }
      })
      console.log('初始化蓝牙适配器')
    },
    fail: function (res) {
      console.log(res)
      if (res.errMsg.indexOf("already opened") != -1){
        notOpenBle = false
        wx.getBluetoothAdapterState({
          success: function (res) {
            if (res.discovering == true) {
              console.log('正在搜索')
              findingDevice(0, function (dev) {
                success(dev)
              })
            } else {
              console.log('开始搜索')
              searchDevice(success, fail)
            }
          }
        })
        console.log('初始化蓝牙适配器')
        return
      }
      notOpenBle = true
      fail('请检查蓝牙是否打开')
    }
  })
}

function searchDevice(success, fail){
  // 开始扫描
  // var uuid = device_QHC_UUID
  // var system = wx.getSystemInfoSync()
  // if (system.platform == 'android'){
  // var str = new String(system.system)
  // console.log('系统版本', parseInt(str))
  // }
  wx.startBluetoothDevicesDiscovery({
    // services: [device_QHC_UUID],
    allowDuplicatesKey: true,
    success: function (res) {
      console.log('开始扫描',res)
      findingDevice(0, function (dev) {
        success(dev)
      })
    },
    fail: function (res) {
      console.log('扫描报错',res)
      console.log(res)
    }
  })
}

// 搜索到设备
function findingDevice(filter,valueChange){
  
  var response = {};
  response.status = '设备已连接，请站上体重秤'
  valueChange(response)
  console.log('开启搜索监听')
  wx.onBluetoothDeviceFound(function(res) {
    // console.log('扫描到',res)
    var same = false
    var currentDev ;
    if(res.deviceId){ // android
      currentDev = res
    } else if (res.devices){ // ios
      currentDev = res.devices[0]
    }
    // 解析广播数据
    var data;
    if (wx.getSystemInfoSync().version == '6.5.7'){
      data = wx.base64ToArrayBuffer(currentDev.advertisData)
    } else {
      data = currentDev.advertisData
    }
    
    var str = buf2hex(data).toLowerCase()
    if (res.deviceId) { // android
      str = buf2hex(currentDev.advertisData).toLowerCase()
    }
    var index = str.indexOf(weighing_scale_type.toLowerCase())
    // console.log(str)
    if (index == -1){ // 过滤电子秤
      // console.log('不是电子秤')
      return
    }
    if (str.indexOf(weighing_scale_close) != -1) {
      
      console.log('设备休眠')
      return
    }
    for(var i = 0;i < devList.length;i++){
      var item = devList[i]
      if(item.deviceId == currentDev.deviceId){
        same = true
        
        var dataStr = str.substr(index + weighing_scale_type.length - 4,16)
        // console.log('测量数据', dataStr)
        var weightH = dataStr.substr(4,2)
        var weightL = dataStr.substr(6,2)

        var weightInt = parseInt(weightH.substr(1, 1) + weightL, 16) / 10
        // 转成str加上小数点
        var wStr = weightInt.toString()
        response.weight = weightInt
        if (wStr.indexOf('.') == -1){
          response.weight = wStr + '.0'
        }
        console.log('测量数据', weightInt)
        if (dataStr.toLowerCase().indexOf(weighing_scale_measure_end) != -1) {
          response.status = '测量完成'
          if(weightInt > 150){
            return
          }
          valueChange(response)
          return
        }
        // console.log('返回测量数据', dataStr)
        response.status = '设备已连接，测量中'
      }
    }
    if(!same){
      devList.push(currentDev)
      response.devList = devList
      response.status = '搜索到设备，正在连接'
    }
    response.devList = devList
    valueChange(response)
  })
}

function buf2hex(buffer) { // buffer is an ArrayBuffer
  return Array.prototype.map.call(new Uint8Array(buffer), x => ('00' + x.toString(16)).slice(-2)).join('');
}

function closeBLE(){
  wx.stopBluetoothDevicesDiscovery({
    complete: function (res) { 
      console.log('停止搜索', res)
    },
  })
  wx.closeBluetoothAdapter({
    complete: function (res) {
      console.log('关闭蓝牙',res)
    },
  })
}

module.exports = {
  openBluetoothAdapter: openBluetoothAdapter,
  findingDevice : findingDevice,
  closeBLE: closeBLE
}