import serial
import serial.tools.list_ports

class SerialManager:
    def __init__(self, buffers):
        self.serials = {}
        self.buffers = buffers

    def open_port(self, port_name, baudrate=9600,bytesize = 8,parity = 'N',stopbits = 1,flowcontrol = 'None'):
        """打开串口"""
        try:
            if port_name in self.serials and self.serials[port_name].is_open:
                print(f"串口 {port_name} 已经打开，正在关闭...")
                self.serials[port_name].close()
            ser = serial.Serial(port_name, baudrate, bytesize, parity, stopbits, flowcontrol)
            self.serials[port_name] = ser
            self.buffers[port_name] = b''  # 初始化缓冲区
            print(f"创建串口对象 {port_name} 成功，当前状态: is_open={ser.is_open}")
            return True
        except Exception as e:
            print(f"串口打开失败: {e}")
            return False

    def close_port(self, port_name):
        """关闭串口"""
        try:
            if port_name in self.serials and self.serials[port_name].is_open:
                self.serials[port_name].close()
            del self.serials[port_name]
            del self.buffers[port_name]
            return True
        except Exception as e:
            print(f"串口关闭失败: {e}")
            return False

    def port_all_close(self):
        """关闭所有串口"""
        for port_name in self.serials:
            self.serials[port_name].close()
            del self.buffers[port_name]
        self.serials = {}

    def reopen_port(self, port_name):
        """重新打开串口"""
        try:
            if port_name in self.serials:
                self.serials[port_name].close()
                self.serials[port_name].open()
                return True
            else:
                print(f"串口 {port_name} 不存在或未打开")
                return False
        except Exception as e:
            print(f"串口重新打开失败: {e}")



    def read_data(self, port_name):
        """读取串口数据"""
        try:
            ser = self.serials[port_name]
            num = ser.in_waiting
            if num > 0:
                data = ser.read(num)
                if port_name not in self.buffers:
                    self.buffers[port_name] = b''  # 初始化为空字
                self.buffers[port_name] += data
                # 设置 buffer 的最大大小（元素数量）
                max_buffer_length = 256  # 根据需要调整最大长度

                # 计算当前 buffer 的总长度
                current_length = len(self.buffers[port_name])

                # 检查并限制 buffer 的长度
                if current_length > max_buffer_length:
                    # 移除最早添加的字节，直到总长度不超过 max_buffer_length
                    while current_length > max_buffer_length and self.buffers[port_name]:
                        removed_byte = self.buffers[port_name][0:1]
                        self.buffers[port_name] = self.buffers[port_name][1:]
                        current_length -= len(removed_byte)
                return data

        except Exception as e:
            print(f"读取串口数据失败: {e}")
            return False

    def write_data(self, port_name, data):
        """向串口发送数据"""
        try:
            ser = self.serials[port_name]
            ser.write(data)
            return True
        except Exception as e:
            print(f"写入串口数据失败: {e}")
            return False