package main

import (
	"context"
	"errors"
	"log"
	"net/http"
	"os/signal"
	"syscall"
	"time"

	"booklib/cmd/webui/api"
	"booklib/internal/config"
	"booklib/internal/db"
	"booklib/internal/redispkg"
	"booklib/internal/scanner"
	"booklib/internal/seed"
	"booklib/internal/store"
)

func main() {
	cfg, err := config.Load()
	if err != nil {
		log.Fatalf("config: %v", err)
	}
	ctx, stop := signal.NotifyContext(context.Background(), syscall.SIGINT, syscall.SIGTERM)
	defer stop()

	p, err := db.Connect(ctx, cfg.DatabaseURL)
	if err != nil {
		log.Fatalf("db connect: %v", err)
	}
	defer p.Close()
	if err := db.Migrate(ctx, p); err != nil {
		log.Fatalf("migrate: %v", err)
	}
	st := store.New(p)
	if err := seed.Admin(ctx, st, cfg.AdminUser, cfg.AdminPassword); err != nil {
		log.Fatalf("seed: %v", err)
	}
	rdb := redispkg.New(cfg.RedisURL)
	sc := scanner.New(st, cfg, rdb)
	go sc.Run(ctx)

	serveErr := make(chan error, 1)
	srv := &http.Server{Addr: cfg.Addr, Handler: api.NewRouter(cfg, st, rdb, sc),
		ReadHeaderTimeout: 10 * time.Second}
	go func() {
		log.Printf("listening on %s", cfg.Addr)
		if err := srv.ListenAndServe(); err != nil && !errors.Is(err, http.ErrServerClosed) {
			serveErr <- err
		}
		close(serveErr)
	}()

	// Wait for signal OR serve error.
	select {
	case <-ctx.Done():
	case err := <-serveErr:
		if err != nil {
			log.Printf("serve: %v", err)
		}
	}
	// stop() 先取消 ctx → scanner 循环退出;再等 HTTP 收尾。
	// 在途 ScanLibraryByID(WithoutCancel)不受 ctx 控制,靠 redis 锁 TTL 兜底(已文档化的上限)。
	stop()
	shutdownCtx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
	defer cancel()
	if err := srv.Shutdown(shutdownCtx); err != nil {
		log.Printf("shutdown: %v", err)
	}
}