package gpio_monitor

import (
	"context"
	"fmt"
	"os"
	"strconv"
	"time"

	"FireLeave_tool/logger"
)

const (
	// ButtonGPIO GPIO引脚编号
	ButtonGPIO = 111
	// DebounceTime 去抖动时间
	DebounceTime = 200 * time.Millisecond
)

// GPIOButtonMonitor GPIO按钮监视器
type GPIOButtonMonitor struct {
	gpioPin        int
	isRunning      bool
	lastState      bool
	lastChange     time.Time
	lastAlertTime  time.Time
	cooldownTime   time.Duration
	cooldownActive bool
	onPress        func()
}

// NewGPIOButtonMonitor 创建GPIO按钮监视器
func NewGPIOButtonMonitor(gpioPin int) *GPIOButtonMonitor {
	return &GPIOButtonMonitor{
		gpioPin:        gpioPin,
		isRunning:      false,
		lastState:      false,
		lastChange:     time.Now(),
		lastAlertTime:  time.Now().Add(-6 * time.Second), // 初始化为6秒前，确保第一次可以触发
		cooldownTime:   5 * time.Second,                  // 5秒冷却时间
		cooldownActive: false,                            // 冷却期状态
	}
}

func (m *GPIOButtonMonitor) SetOnPress(handler func()) {
	m.onPress = handler
}

// InitGPIO 初始化GPIO
func (m *GPIOButtonMonitor) InitGPIO() error {
	gpioPath := fmt.Sprintf("/sys/class/gpio/gpio%d", m.gpioPin)

	// 检查GPIO是否已导出
	if _, err := os.Stat(gpioPath); os.IsNotExist(err) {
		// 导出GPIO
		if err := os.WriteFile("/sys/class/gpio/export", []byte(strconv.Itoa(m.gpioPin)), 0666); err != nil {
			return fmt.Errorf("failed to export GPIO %d: %v", m.gpioPin, err)
		}
		// 等待导出完成
		time.Sleep(50 * time.Millisecond)
	}

	// 检查并设置方向为输入
	directionPath := fmt.Sprintf("%s/direction", gpioPath)
	directionBytes, err := os.ReadFile(directionPath)
	if err != nil {
		return fmt.Errorf("failed to read GPIO direction: %v", err)
	}

	direction := string(directionBytes)
	if direction != "in\n" && direction != "in" {
		if err := os.WriteFile(directionPath, []byte("in"), 0666); err != nil {
			return fmt.Errorf("failed to set GPIO direction to in: %v", err)
		}
		// 等待设置完成
		time.Sleep(10 * time.Millisecond)
	}

	if log := logger.GlobalLoggerManager.GetLogger("gpio"); log != nil {
		log.Printf("GPIO %d initialized successfully as input", m.gpioPin)
	} else if log := logger.GlobalLoggerManager.GetLogger("reporter"); log != nil {
		log.Printf("GPIO %d initialized successfully as input", m.gpioPin)
	}
	return nil
}

// ReadGPIOValue 读取GPIO值
func (m *GPIOButtonMonitor) ReadGPIOValue() (bool, error) {
	valuePath := fmt.Sprintf("/sys/class/gpio/gpio%d/value", m.gpioPin)
	valueBytes, err := os.ReadFile(valuePath)
	if err != nil {
		return false, fmt.Errorf("failed to read GPIO value: %v", err)
	}

	value := string(valueBytes)
	return value == "1\n" || value == "1", nil
}

// Start 启动GPIO监控
func (m *GPIOButtonMonitor) Start(ctx context.Context) error {
	// 初始化GPIO
	if err := m.InitGPIO(); err != nil {
		return fmt.Errorf("failed to initialize GPIO: %v", err)
	}

	m.isRunning = true
	if log := logger.GlobalLoggerManager.GetLogger("gpio"); log != nil {
		log.Printf("Started monitoring GPIO %d for button alerts", m.gpioPin)
	} else if log := logger.GlobalLoggerManager.GetLogger("reporter"); log != nil {
		log.Printf("Started monitoring GPIO %d for button alerts", m.gpioPin)
	}

	go func() {
		defer func() {
			m.isRunning = false
			if log := logger.GlobalLoggerManager.GetLogger("gpio"); log != nil {
				log.Printf("Stopped monitoring GPIO %d", m.gpioPin)
			} else if log := logger.GlobalLoggerManager.GetLogger("reporter"); log != nil {
				log.Printf("Stopped monitoring GPIO %d", m.gpioPin)
			}
		}()

		for {
			select {
			case <-ctx.Done():
				return
			default:
				// 读取GPIO值
				currentState, err := m.ReadGPIOValue()
				if err != nil {
					if log := logger.GlobalLoggerManager.GetLogger("gpio"); log != nil {
						log.Printf("Error reading GPIO %d value: %v", m.gpioPin, err)
					} else if log := logger.GlobalLoggerManager.GetLogger("reporter"); log != nil {
						log.Printf("Error reading GPIO %d value: %v", m.gpioPin, err)
					}
					time.Sleep(100 * time.Millisecond)
					continue
				}

				// 检查状态是否变化
				if currentState != m.lastState {
					// 记录状态变化
					if log := logger.GlobalLoggerManager.GetLogger("gpio"); log != nil {
						log.Printf("GPIO %d state changed: %t → %t", m.gpioPin, m.lastState, currentState)
					} else if log := logger.GlobalLoggerManager.GetLogger("reporter"); log != nil {
						log.Printf("GPIO %d state changed: %t → %t", m.gpioPin, m.lastState, currentState)
					}

					// 状态变化时更新lastChange
					m.lastChange = time.Now()

					// 立即更新lastState，避免重复触发状态变化日志
					m.lastState = currentState

					// 只输出true状态
					if currentState {
						if log := logger.GlobalLoggerManager.GetLogger("gpio"); log != nil {
							log.Printf("GPIO %d current state: %t", m.gpioPin, currentState)
						} else if log := logger.GlobalLoggerManager.GetLogger("reporter"); log != nil {
							log.Printf("GPIO %d current state: %t", m.gpioPin, currentState)
						}
					}
				}

				// 检查冷却期状态
				if time.Since(m.lastAlertTime) < m.cooldownTime {
					if !m.cooldownActive {
						m.cooldownActive = true
						// 只记录一次冷却期开始
					}
				} else {
					if m.cooldownActive {
						// 只记录一次冷却期结束
						if log := logger.GlobalLoggerManager.GetLogger("gpio"); log != nil {
							log.Printf("GPIO %d cooldown period ended", m.gpioPin)
						} else if log := logger.GlobalLoggerManager.GetLogger("reporter"); log != nil {
							log.Printf("GPIO %d cooldown period ended", m.gpioPin)
						}
						m.cooldownActive = false
					}
				}

				// 检查是否稳定，且当前状态为true（高电平）
				if currentState && time.Since(m.lastChange) > DebounceTime {
					// 检查冷却期
					if time.Since(m.lastAlertTime) >= m.cooldownTime {
						// 检测到稳定的高电平，切换事件周期
						if log := logger.GlobalLoggerManager.GetLogger("gpio"); log != nil {
							log.Printf("GPIO %d detected stable high level after debounce, triggering fire_leave pause...", m.gpioPin)
						} else if log := logger.GlobalLoggerManager.GetLogger("reporter"); log != nil {
							log.Printf("GPIO %d detected stable high level after debounce, triggering fire_leave pause...", m.gpioPin)
						}

						// 切换事件周期
						if m.onPress != nil {
							m.onPress()
						}

						// 更新lastAlertTime，开始冷却期
						m.lastAlertTime = time.Now()
						if log := logger.GlobalLoggerManager.GetLogger("gpio"); log != nil {
							log.Printf("GPIO %d alert sent, cooldown period started (5s)", m.gpioPin)
						} else if log := logger.GlobalLoggerManager.GetLogger("reporter"); log != nil {
							log.Printf("GPIO %d alert sent, cooldown period started (5s)", m.gpioPin)
						}

						// 重置lastChange，避免重复触发
						m.lastChange = time.Now()
					}
				}

				// 增加休眠时间，减少CPU占用和日志频率
				time.Sleep(100 * time.Millisecond)
			}
		}
	}()

	return nil
}

// IsRunning 检查监视器是否正在运行
func (m *GPIOButtonMonitor) IsRunning() bool {
	return m.isRunning
}