from threading import Timer
from time import sleep

from dynaconf.base import Settings
from serial import Serial, SerialException

from PyQt5.QtCore import QObject, pyqtSignal

from core.edge_component import device, EdgeComponent, service


def get_crc(pc_rec, i_len):
    i_crc = 0xFFFF  # 初始化CRC值
    if i_len <= 0:
        return None  # 长度为0时返回None

    for ix in range(i_len):
        i_crc ^= pc_rec[ix]  # 进行异或运算
        for iy in range(8):
            if (i_crc & 1) != 0:
                i_crc = (i_crc >> 1) ^ 0xA001  # CRC多项式
            else:
                i_crc >>= 1  # 右移一位

    # 返回高字节和低字节
    return [(i_crc >> 8) & 0xFF, i_crc & 0xFF]


def read_packet(addr):
    pack = bytearray([0xAB, 0xCD, 0x00, 0x03, addr, 0x00, 0x00])
    crc = get_crc(pack, 7)
    pack.append(crc[0])
    pack.append(crc[1])
    return pack


class UpsSignals(QObject):
    battery_change = pyqtSignal(int)
    state_change = pyqtSignal(int)


@device("ups", auto_start=True)
class Ups(EdgeComponent):

    signals = UpsSignals()

    def __init__(self, context):
        super(Ups, self).__init__(context)
        self.port = '/dev/ttyUSB0'
        self.bytesize = 8
        self.parity = 'N'
        self.stopbits = 1
        self.baudrate = 115200
        self.serial = None
        self.read_timer = None
        self.cmd_read_delay = 0.3

    def configure(self, setting: Settings) -> None:
        self.port = setting.get('ups.port', '/dev/ttyUSB0')
        self.baudrate = setting.get('ups.baudrate', 115200)
        self.bytesize = setting.get('ups.bytesize', 8)
        self.stopbits = setting.get('ups.stopbits', 1)
        self.parity = setting.get('ups.parity', 'N')
        self.cmd_read_delay = setting.get('ups.cmd.read.delay', 0.3)

        self.logger.info(f"Ups configure done.")

    @service()
    def start(self) -> None:
        # 打开串口
        try:
            self.serial = Serial(port=self.port, baudrate=self.baudrate, stopbits=self.stopbits, parity=self.parity,
                                 bytesize=self.bytesize, timeout=2.0)
            self.logger.info(f"open serial port: {self.port} baudrate:{self.baudrate} stopbits:{self.stopbits} bytesize:{self.bytesize}")
        except SerialException as e:
            self.logger.error(f"Failed to open serial port: {e}")

        # 启动读取数据
        self.read_battery()
        self.logger.info('Ups start!')
        super().start()

    def read_battery(self):
        if self.serial is not None and self.serial.isOpen():
            # 读取状态
            read_state_pack = read_packet(0x05)
            self.serial.write(read_state_pack)
            # self.logger.info(f"发送查询状态指令: {read_state_pack.hex()}")
            sleep(self.cmd_read_delay)
            if self.serial.in_waiting >= 9:
                # 返回指令释义：
                # AB CD 00 03 05 64 00 00 00
                data = self.serial.read(9)
                # self.logger.info(f'收到查询状态数据：{data.hex()}')
                if data[0] == 0xAB and data[1] == 0xCD:
                    state = data[6]
                    # self.logger.info(f'当前状态：{state}')
                    self.signals.state_change.emit(state)

            # 读取电量
            read_battery_pack = read_packet(0x01)
            self.serial.write(read_battery_pack)
            # self.logger.info(f"发送查询电量指令: {read_battery_pack.hex()}")
            sleep(self.cmd_read_delay)
            if self.serial.in_waiting >= 9:
                # 返回指令释义：
                # abcd000301003c4042
                data = self.serial.read(9)
                # self.logger.info(f'收到查询电量数据：{data.hex()}')
                if data[0] == 0xAB and data[1] == 0xCD:
                    battery = data[6]
                    # self.logger.info(f'当前电量：{battery}')
                    self.signals.battery_change.emit(battery)

        self.read_timer = Timer(3, self.read_battery)
        self.read_timer.start()

    @service()
    def stop(self) -> None:
        if self.read_timer is not None:
            self.read_timer.cancel()

        if self.serial is not None:
            self.serial.close()
            self.serial = None

        self.logger.info('Ups stop!')
        super().stop()


if __name__=="__main__":
    ups = Ups()
    ups.start()
    sleep(30)
    ups.stop()