package main

import (
	"context"
	"fmt"
	"log/slog"
	"os"
	"os/signal"
	"strings"
	"syscall"
	"time"

	"github.com/joho/godotenv"
)

const (
	trafficUpdateInterval = 30 * time.Second
	saveTrafficInterval   = 5 * time.Minute
	reportInterval        = 5 * time.Minute
	httpTimeout           = 30 * time.Second
)

type Config struct {
	MasterAddress string
	NodeName      string
	NodeKey       string
}

func loadConfig() (Config, error) {
	godotenv.Load()

	master := os.Getenv("MASTER_ADDRESS")
	nodeName := os.Getenv("NODE_NAME")
	nodeKey := os.Getenv("NODE_KEY")

	if master == "" || nodeName == "" || nodeKey == "" {
		return Config{}, fmt.Errorf("配置不完整，请检查 .env 文件")
	}

	return Config{
		MasterAddress: strings.TrimRight(master, "/"),
		NodeName:      nodeName,
		NodeKey:       nodeKey,
	}, nil
}

func saveTrafficOnExit(tm *TrafficMonitor) {
	month, upload, download := tm.GetSnapshot()
	if err := saveMonthlyTraffic(month, upload, download); err != nil {
		slog.Error("退出前保存流量数据失败", "error", err)
	} else {
		slog.Info("流量数据已保存", "upload_mb", fmt.Sprintf("%.2f", upload), "download_mb", fmt.Sprintf("%.2f", download))
	}
}

func main() {
	slog.Info("探针程序启动")

	config, err := loadConfig()
	if err != nil {
		slog.Error("加载配置失败", "error", err)
		return
	}

	trafficMonitor := NewTrafficMonitor()

	if month, upload, download, err := loadMonthlyTraffic(); err == nil {
		trafficMonitor.SetMonthlyTraffic(month, upload, download)
		slog.Info("已加载月流量数据",
			"upload_mb", fmt.Sprintf("%.2f", upload),
			"download_mb", fmt.Sprintf("%.2f", download))
	}

	slog.Info("监控程序运行中", "node", config.NodeName, "master", config.MasterAddress)

	ctx, stop := signal.NotifyContext(context.Background(), os.Interrupt, syscall.SIGTERM)
	defer stop()

	go func() {
		ticker := time.NewTicker(trafficUpdateInterval)
		defer ticker.Stop()
		for {
			select {
			case <-ctx.Done():
				return
			case <-ticker.C:
				if err := trafficMonitor.UpdateTraffic(); err != nil {
					slog.Error("更新流量失败", "error", err)
				}
			}
		}
	}()

	go func() {
		ticker := time.NewTicker(saveTrafficInterval)
		defer ticker.Stop()
		for {
			select {
			case <-ctx.Done():
				return
			case <-ticker.C:
				month, upload, download := trafficMonitor.GetSnapshot()
				if err := saveMonthlyTraffic(month, upload, download); err != nil {
					slog.Error("保存流量失败", "error", err)
				}
			}
		}
	}()

	go func() {
		ticker := time.NewTicker(reportInterval)
		defer ticker.Stop()
		for {
			select {
			case <-ctx.Done():
				return
			case <-ticker.C:
				if err := submitData(config, trafficMonitor); err != nil {
					slog.Error("上报失败", "error", err)
				}
			}
		}
	}()

	if err := submitData(config, trafficMonitor); err != nil {
		slog.Error("初始上报失败", "error", err)
	}

	<-ctx.Done()
	slog.Info("收到退出信号，正在保存数据...")
	saveTrafficOnExit(trafficMonitor)
	slog.Info("探针程序已退出")
}