import logging
import json
import os
from PySide6.QtWidgets import QWidget, QMessageBox
from PySide6.QtCore import Signal
from utils.config_loader import ConfigLoader

class PLCSettingsWidget(QWidget):
    """PLC设置控制器"""
    
    # 定义信号
    settings_changed = Signal()  # 设置变更信号
    
    def __init__(self, parent=None):
        """初始化控制器
        
        Args:
            parent: 父窗口
        """
        super().__init__(parent)
        self.parent = parent
        self.config = ConfigLoader.get_instance()
        
        # 获取UI控件引用
        self.modbus_host_input = parent.modbus_host_input
        self.modbus_port_input = parent.modbus_port_input
        self.modbus_test_button = parent.modbus_test_button
        self.plc_save_button = parent.plc_save_button
        
        # 连接信号和槽
        self.connect_signals()
        
        # 加载配置
        self.load_config()
    
    def connect_signals(self):
        """连接信号和槽"""
        self.modbus_test_button.clicked.connect(self.test_modbus_connection)
        self.plc_save_button.clicked.connect(self.save_config)
    
    def load_config(self):
        """加载配置"""
        try:
            # 加载Modbus配置
            host = self.config.get_value("modbus.host")
            port = self.config.get_value("modbus.port")
            
            self.modbus_host_input.setText(host if host else "localhost")
            self.modbus_port_input.setText(str(port) if port else "502")
            
            logging.info("已加载PLC配置")
        except Exception as e:
            logging.error(f"加载PLC配置失败: {str(e)}")
            QMessageBox.critical(self, "错误", f"加载PLC配置失败: {str(e)}")
    
    def save_config(self):
        """保存配置"""
        try:
            # 获取输入值
            host = self.modbus_host_input.text().strip()
            port = self.modbus_port_input.text().strip()
            
            # 验证输入
            if not host:
                QMessageBox.warning(self, "警告", "请输入Modbus主机地址")
                return
            
            if not port:
                QMessageBox.warning(self, "警告", "请输入Modbus端口")
                return
            
            try:
                port_int = int(port)
                if port_int < 1 or port_int > 65535:
                    QMessageBox.warning(self, "警告", "端口号必须在1-65535之间")
                    return
            except ValueError:
                QMessageBox.warning(self, "警告", "端口号必须是整数")
                return
            
            # 更新配置
            self.config.set_value("modbus.host", host)
            self.config.set_value("modbus.port", port)
            self.config.save_config()
            
            # 发送信号
            self.settings_changed.emit()
            
            # 提示成功
            QMessageBox.information(self, "成功", "PLC配置已保存")
            logging.info(f"已保存PLC配置: host={host}, port={port}")
        except Exception as e:
            logging.error(f"保存PLC配置失败: {str(e)}")
            QMessageBox.critical(self, "错误", f"保存PLC配置失败: {str(e)}")
    
    def test_modbus_connection(self):
        """测试Modbus连接"""
        try:
            # 获取输入值
            host = self.modbus_host_input.text().strip()
            port = self.modbus_port_input.text().strip()
            
            # 验证输入
            if not host:
                QMessageBox.warning(self, "警告", "请输入Modbus主机地址")
                return
            
            if not port:
                QMessageBox.warning(self, "警告", "请输入Modbus端口")
                return
            
            try:
                port_int = int(port)
            except ValueError:
                QMessageBox.warning(self, "警告", "端口号必须是整数")
                return
            
            # 导入ModbusUtils
            from utils.modbus_utils import ModbusUtils
            
            # 创建Modbus连接
            modbus = ModbusUtils(host=host, port=port_int)
            client = modbus.get_client()
            
            if client:
                QMessageBox.information(self, "成功", f"Modbus连接成功: {host}:{port}")
                logging.info(f"Modbus连接测试成功: {host}:{port}")
            else:
                QMessageBox.warning(self, "警告", f"Modbus连接失败: {host}:{port}")
                logging.warning(f"Modbus连接测试失败: {host}:{port}")
            
            # 关闭连接
            modbus.close_client(client)
        except Exception as e:
            logging.error(f"测试Modbus连接失败: {str(e)}")
            QMessageBox.critical(self, "错误", f"测试Modbus连接失败: {str(e)}")
    
    def on_settings_changed(self):
        """设置变更处理"""
        # 重新加载配置
        self.load_config()