package main

import (
	"encoding/json"
	"fmt"
	"io"
	"log"
	"net/http"
	"os"
	"os/exec"
	"path/filepath"
	"strings"
	"time"
)

// ProcessConfig 进程配置结构体
type ProcessConfig struct {
	ProcessName   string `json:"process_name"`
	FileName      string `json:"file_name"` // 文件名
	KumaURL       string `json:"kuma_url"`
	CheckInterval int    `json:"check_interval"`
}

// Config 整体配置结构体
type Config struct {
	Processes []ProcessConfig `json:"processes"`
}

// ProcessMonitor 进程监控结构体
type ProcessMonitor struct {
	config     ProcessConfig
	httpClient *http.Client
	status     string
	logDir     string
}

// NewProcessMonitor 创建新的进程监控
func NewProcessMonitor(config ProcessConfig, logDir string) *ProcessMonitor {
	return &ProcessMonitor{
		config:     config,
		httpClient: &http.Client{},
		status:     "down",
		logDir:     logDir,
	}
}

// LoadConfig 加载配置文件
func LoadConfig(filename string) (*Config, error) {
	file, err := os.Open(filename)
	if err != nil {
		return nil, err
	}
	defer file.Close()

	var config Config
	if err := json.NewDecoder(file).Decode(&config); err != nil {
		return nil, err
	}
	return &config, nil
}

// InitLogFile 初始化日志文件
func InitLogFile(logDir string) (*os.File, error) {
	if err := os.MkdirAll(logDir, 0755); err != nil {
		return nil, fmt.Errorf("failed to create log directory: %v", err)
	}

	logFile := filepath.Join(logDir, time.Now().Format("2006-01-02")+".log")
	file, err := os.OpenFile(logFile, os.O_APPEND|os.O_CREATE|os.O_WRONLY, 0666)
	if err != nil {
		return nil, fmt.Errorf("failed to open log file: %v", err)
	}
	return file, nil
}

// IsProcessRunning 检查进程是否正在运行
func (pm *ProcessMonitor) IsProcessRunning() bool {
	output, err := exec.Command("tasklist").Output()
	if err != nil {
		log.Printf("Error retrieving process list: %v", err)
		return false
	}

	lines := string(output)
	for _, line := range strings.Split(lines, "\n") {
		if strings.Contains(line, pm.config.ProcessName) {
			// 如果指定了文件名，则检查文件名
			if pm.config.FileName == "" || strings.Contains(line, pm.config.FileName) {
				return true
			}
		}
	}
	return false
}

// PushStatusToKuma 向 Uptime Kuma 推送状态
func (pm *ProcessMonitor) PushStatusToKuma() error {
	response, err := pm.httpClient.Get(fmt.Sprintf("%s?status=%s", pm.config.KumaURL, pm.status))
	if err != nil {
		return err
	}
	defer response.Body.Close()
	log.Printf("Pushed status '%s' for process '%s' fileName '%s' to Uptime Kuma: %s", pm.status, pm.config.ProcessName, pm.config.FileName, response.Status)
	return nil
}

// Monitor 监控进程状态
func (pm *ProcessMonitor) Monitor() {
	ticker := time.NewTicker(time.Duration(pm.config.CheckInterval) * time.Second)
	defer ticker.Stop()

	pm.checkAndPushStatus() // 启动时立即检查一次

	for {
		select {
		case <-ticker.C:
			pm.checkAndPushStatus()
		case <-time.After(24 * time.Hour): // 每天执行日志清理
			pm.cleanOldLogs()
		}
	}
}

// checkAndPushStatus 检查进程状态并推送到 Uptime Kuma
func (pm *ProcessMonitor) checkAndPushStatus() {
	pm.status = "down"
	if pm.IsProcessRunning() {
		pm.status = "up"
	}
	if err := pm.PushStatusToKuma(); err != nil {
		log.Printf("Error pushing status for process '%s' fileName '%s': %v", pm.config.ProcessName, pm.config.FileName, err)
	}
}

// cleanOldLogs 清理旧日志
func (pm *ProcessMonitor) cleanOldLogs() {
	logFiles, err := os.ReadDir(pm.logDir)
	if err != nil {
		log.Printf("Error reading log directory: %v", err)
		return
	}

	threshold := time.Now().AddDate(0, 0, -30) // 30天前的日期
	for _, logFile := range logFiles {
		if logFile.Type().IsRegular() {
			if fileInfo, err := logFile.Info(); err == nil {
				if fileInfo.ModTime().Before(threshold) {
					if err := os.Remove(filepath.Join(pm.logDir, logFile.Name())); err != nil {
						log.Printf("Error deleting old log file '%s': %v", logFile.Name(), err)
					} else {
						log.Printf("Deleted old log file: '%s'", logFile.Name())
					}
				}
			}
		}
	}
}

func main() {
	logDir := "logs"

	logFile, err := InitLogFile(logDir)
	if err != nil {
		log.Fatalf("Error initializing log file: %v\n", err)
	}
	defer logFile.Close()

	// 设置日志同时输出到控制台和文件
	multiWriter := io.MultiWriter(logFile, os.Stdout)
	log.SetOutput(multiWriter)

	config, err := LoadConfig("config.json")
	if err != nil {
		log.Fatalf("Error loading config: %v", err)
	}

	// 启动监控
	for _, processConfig := range config.Processes {
		pm := NewProcessMonitor(processConfig, logDir)
		go pm.Monitor()
	}

	select {} // 阻止主进程退出
}