// 我们past后端（Go 版）：API 与 PHP 版 backend/api/index.php 完全兼容。
package main

import (
	"context"
	"flag"
	"fmt"
	"io"
	"log/slog"
	"net/http"
	"os"
	"os/signal"
	"path/filepath"
	"syscall"
	"time"
	_ "time/tzdata" // Windows 没有系统时区库，内嵌 tzdata 保证 Asia/Shanghai 可用

	"past/internal/config"
	"past/internal/geo"
	"past/internal/handler"
	"past/internal/httpapi"
	"past/internal/notify"
	"past/internal/store"
	"past/internal/upload"
	"past/internal/wechat"
	"past/web"
)

// version 由构建时 -ldflags 注入
var version = "dev"

func main() {
	cfgPath := flag.String("config", "config.yaml", "配置文件路径")
	showVer := flag.Bool("version", false, "显示版本")
	svcCmd := flag.String("service", "", "Windows 服务管理: install | uninstall | start | stop")
	flag.Parse()
	if *showVer {
		fmt.Println("past-server", version)
		return
	}
	if *svcCmd != "" {
		if err := serviceControl(*svcCmd, *cfgPath); err != nil {
			fmt.Fprintln(os.Stderr, "错误:", err)
			os.Exit(1)
		}
		return
	}

	// 作为 Windows 服务运行时，工作目录是 System32：配置文件相对路径按可执行文件所在目录解析
	if !filepath.IsAbs(*cfgPath) {
		if exe, err := os.Executable(); err == nil {
			if _, err := os.Stat(*cfgPath); err != nil {
				*cfgPath = filepath.Join(filepath.Dir(exe), *cfgPath)
			}
		}
	}

	if runAsServiceIfNeeded(func(stop <-chan struct{}) { serve(*cfgPath, stop) }) {
		return
	}
	// 控制台模式：Ctrl+C / SIGTERM 触发优雅退出
	stop := make(chan struct{})
	go func() {
		quit := make(chan os.Signal, 1)
		signal.Notify(quit, syscall.SIGINT, syscall.SIGTERM)
		<-quit
		close(stop)
	}()
	serve(*cfgPath, stop)
}

// serve 启动全部组件并阻塞到 stop 关闭
func serve(cfgPath string, stop <-chan struct{}) {
	// 与 PHP date_default_timezone_set('Asia/Shanghai') 一致
	if loc, err := time.LoadLocation("Asia/Shanghai"); err == nil {
		time.Local = loc
	}

	cfg, err := config.Load(cfgPath)
	if err != nil {
		slog.Error("配置加载失败", "err", err)
		os.Exit(1)
	}
	// 确保必要目录存在（对应 config.php 中的 $dirs）
	for _, d := range []string{"data", "data/tmp", "uploads", "uploads/avatars", "uploads/couples", "uploads/users"} {
		os.MkdirAll(filepath.Join(cfg.DataDir, d), 0755)
	}
	// 日志：stdout + data/go-server.log（Windows 服务没有控制台，文件日志是主要途径）
	logOut := io.Writer(os.Stdout)
	if f, err := os.OpenFile(filepath.Join(cfg.LogDir(), "go-server.log"), os.O_CREATE|os.O_WRONLY|os.O_APPEND, 0644); err == nil {
		logOut = io.MultiWriter(os.Stdout, f)
		defer f.Close()
	}
	slog.SetDefault(slog.New(slog.NewTextHandler(logOut, &slog.HandlerOptions{Level: slog.LevelInfo})))

	db, err := store.Open(cfg.DSN())
	if err != nil {
		slog.Error("数据库连接失败", "err", err)
		os.Exit(1)
	}
	db.UploadDir = cfg.UploadDir()
	db.NumericAsString = cfg.PHPCompat < "8.1"
	if err := db.InitSchema(); err != nil {
		slog.Error("数据库初始化失败", "err", err)
		os.Exit(1)
	}

	if err := db.MigrateSmokingRecords(); err != nil {
		slog.Error("抽烟库存迁移失败", "err", err)
		os.Exit(1)
	}
	if err := db.AdvanceUnbindings(); err != nil {
		slog.Error("解绑状态处理失败", "err", err)
		os.Exit(1)
	}
	go db.RunUnbindingWorker()
	wx := wechat.New(cfg.Wechat.AppID, cfg.Wechat.Secret, cfg.Wechat.NotifyTemplateID, cfg.DataDir, db)
	app := &httpapi.App{
		Cfg:    cfg,
		DB:     db,
		Wechat: wx,
		Geo:    geo.New(cfg.TencentMapKey),
		Admin:  httpapi.NewAdminSessions(),
	}
	uploader := &upload.Uploader{Dir: cfg.UploadDir(), MaxSize: cfg.MaxUploadMB * 1024 * 1024, Checker: wx}

	router := httpapi.NewRouter(app, web.AdminFS())
	handler.Register(router, uploader)
	slog.Info("已注册 action", "count", len(router.Actions()))

	if cfg.NotifyIntervalMin > 0 {
		go notify.Run(db, wx, time.Duration(cfg.NotifyIntervalMin)*time.Minute)
	}

	srv := &http.Server{
		Addr:              cfg.Listen,
		Handler:           router.Engine(cfg.Debug),
		ReadHeaderTimeout: 30 * time.Second,
		ReadTimeout:       180 * time.Second, // 大文件上传
		WriteTimeout:      180 * time.Second,
		IdleTimeout:       120 * time.Second,
	}
	go func() {
		slog.Info("服务启动", "version", version, "listen", cfg.Listen, "data_dir", cfg.DataDir)
		if err := srv.ListenAndServe(); err != nil && err != http.ErrServerClosed {
			slog.Error("服务异常退出", "err", err)
			os.Exit(1)
		}
	}()

	<-stop
	ctx, cancel := context.WithTimeout(context.Background(), 15*time.Second)
	defer cancel()
	srv.Shutdown(ctx)
	slog.Info("服务已停止")
}