# hardware/inverter.py
from math import e
import minimalmodbus
import time
from serial import SerialException


class InverterController:
    def __init__(self,port='/dev/ttyUSB0'):
        self.inverter=None
        self.port=port

    def _connect(self)->bool:
        """连接变频器"""
        try:
            self.inverter = minimalmodbus.Instrument(self.port, 1)
            # 2. 配置串口参数
            self.inverter.serial.baudrate = 9600      # 波特率
            self.inverter.serial.bytesize = 8         # 数据位
            self.inverter.serial.parity = 'N'        # 无校验
            self.inverter.serial.stopbits = 1         # 停止位
            self.inverter.serial.timeout = 1.0        # 超时时间
            self.inverter.mode = minimalmodbus.MODE_RTU  # RTU模式
            return True
        except SerialException as e:
            print(f"串口占用或无法连接变频器串口:{e}")
            return False
        except Exception as e:
            print(f"连接变频器异常:{e}")
            return False

    def set_frequency(self, frequency):
        """设置变频器频率"""
        _ret=False
        try:
            if(self._connect()):
                frequency_value = int(frequency * 100)
                self.inverter.write_register(0x7310, frequency_value)
                _ret=True
            else:
                print(f'设置频率{frequency}失败')
        except Exception as e:
            print(f"设置频率{frequency}异常:{e}")
        finally:
            if self.inverter:
                self.inverter.serial.close()
        return _ret

    def read_frequency(self):
        """读取变频器频率"""
        _ret=None
        try:
            if(self._connect()):
                frequency_value = self.inverter.read_register(0x7310)
                _ret=frequency_value / 100
            else:
                print(f"读取频率失败")
        except Exception as e:
            print(f"读取频率异常:{e}")
        finally:
            if self.inverter:
                self.inverter.serial.close()
        return _ret

    def read_status(self):
        """读取变频器启动状态"""
        _ret=None
        try:
            if(self._connect()):
                status_value = self.inverter.read_register(0x3000)
                _ret=status_value
            else:
                print(f"读取启动状态失败")
        except Exception as e:
            print(f"读取启动状态异常:{e}")
        finally:
            if self.inverter:
                self.inverter.serial.close()
        return _ret

    def control(self, action,frequency=230):
        """控制变频器启停"""
        if action not in ['start', 'stop']:
            print(f"无效操作: {action}")
            return False
        _ret=False
        # 先检查动作是否有      
        try:
            if(self._connect()):
                if action == 'start':
                    status_value = self.inverter.read_register(0x3000)
                    ##读取3000H可直接读取变频器的当前状态（0001：正转运行；0002：反转运行；0003：停机；0004：电机参数辨识；0005：故障）。
                    if status_value==3:
                        frequency_value = int(frequency * 100)
                        self.inverter.write_register(0x7310, frequency_value)
                        time.sleep(1)
                        self.inverter.write_register(0x2000, 1)  # 1=正转运行
                        print("启动变频器")
                elif action == 'stop':
                    self.inverter.write_register(0x2000, 6)  # 6=减速停机,5自由停机
                    print("停止变频器") 
                _ret=True
            else:
                print("连接变频器失败")
        except Exception as e:
            print(f"变频器控制错误: {e}")
        finally:
            if self.inverter:
                self.inverter.serial.close()
        return _ret