"""
深圳市普中科技有限公司（PRECHIN 普中）
技術支援：www.prechin.net
PRECHIN
 普中

實驗名稱：藍牙BLE通信
  https://wokwi.com/projects/385882678121037825
接線說明：LED模組-->ESP32 IO
         (D1)-->(15)

         KEY模組-->ESP32 IO
         (K1)-->(14)

實驗現象：程式下載成功後，軟體shell控制台輸出藍牙BLE名稱“ESP32BLE”，D1指示燈快閃，等待APP藍牙連接。
         安卓手機系統，打開應用市場，搜索“BLE藍牙調試助手”下載，打開該APP，選擇藍牙名稱為“ESP32BLE”
         連接，然後按照實驗現象操作即可。

注意事項：

"""

#導入Pin模組
from machine import Pin, Timer
from time import sleep_ms
import ubluetooth

BLE_MSG = ""

class ESP32_BLE():
  def __init__(self, name):
    self.name = name
    self.ble = ubluetooth.BLE()
    self.ble.active(True)
    self.ble.config(gap_name=name)

    # On-board LED pin (GPIO2 on many ESP32 boards)
    self.led = Pin(2, Pin.OUT)
    # Timer for blinking the LED when disconnected
    self.timer1 = Timer(0)

    # Start with disconnected blink pattern
    self.disconnected()

    # Register IRQ callback before registering services
    self.ble.irq(self.ble_irq)

    # Setup Nordic UART GATT service
    self.register()
    self.ble.gatts_write(self.rx, bytes(100))  #修改一次最大接收位元組數100

    # Begin advertising
    self.advertiser()

    self.bleMsg = ""    #接收的消息字符串
    self.bleconnected = False

  def connected(self):
    self.led.value(1)
    self.timer1.deinit()
    self.bleconnected = True

  def disconnected(self):
    self.timer1.init(period=100, mode=Timer.PERIODIC,
             callback=lambda t: self.led.value(not self.led.value()))
    self.bleconnected = False

  def ble_irq(self, event, data):
    if event == 1:
      # _IRQ_CENTRAL_CONNECT 手機連結了此設備
      self.connected()
    elif event == 2:
      # _IRQ_CENTRAL_DISCONNECT 手機斷開此設備
      self.advertiser()
      self.disconnected()
    elif event == 3:
      # _IRQ_GATTS_WRITE 手機發送了資料
      buffer = self.ble.gatts_read(self.rx)
      self.bleMsg = buffer.decode('UTF-8').strip()
      print("Received over BLE:", self.bleMsg)

  def register(self):
    # NUS base UUID and characteristic UUIDs
    service_uuid = '6E400001-B5A3-F393-E0A9-E50E24DCCA9E'
    reader_uuid = '6E400002-B5A3-F393-E0A9-E50E24DCCA9E'
    sender_uuid = '6E400003-B5A3-F393-E0A9-E50E24DCCA9E'

    services = (
      (
        ubluetooth.UUID(service_uuid), #服務ID，可以定義多個服務
        (
          (ubluetooth.UUID(sender_uuid), ubluetooth.FLAG_NOTIFY),
          (ubluetooth.UUID(reader_uuid), ubluetooth.FLAG_WRITE),
        )
      ),
    )

    # Register GATT services and save characteristic handles
    ((self.tx, self.rx,),) = self.ble.gatts_register_services(services)

  def send(self, data):
    #發送數據
    if self.bleconnected == True :
      self.ble.gatts_notify(0, self.tx, data + '\n')

  def advertiser(self):
    #廣播藍牙
    name = bytes(self.name, 'UTF-8')
    adv_data = bytearray(b'\x02\x01\x02') + bytearray((len(name) + 1, 0x09)) + name
    self.ble.gap_advertise(100, adv_data)  #100us發佈一次廣播
    print(adv_data + "\r\n")

def buttons_irq(pin):
  led.value(not led.value())
  print('LED is ON.' if led.value() else 'LED is OFF')
  ble.send('LED is ON.' if led.value() else 'LED is OFF')

if __name__ == "__main__":
  but = Pin(35, Pin.IN)
  but.irq(trigger=Pin.IRQ_FALLING, handler=buttons_irq)

  led = Pin(15, Pin.OUT)

  # Create and start BLE UART device named "ESP32BLE"
  ble = ESP32_BLE("ESP32BLE")
  print("connected ....")
  while True:
    if(len(ble.bleMsg)>0):
      if ble.bleMsg == 'read_LED':
        #打印獲取到的數據
        print(ble.bleMsg)
        # 清空接收的數據
        ble.bleMsg = ""
        print('LED is ON.' if led.value() else 'LED is OFF')
        ble.send('LED is ON.' if led.value() else 'LED is OFF')
    sleep_ms(100)