package main

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

	"todo-hetzner/app/internal/db"
	"todo-hetzner/app/internal/handler"
)

func main() {
	logger := slog.New(slog.NewJSONHandler(os.Stdout, nil))
	if err := run(logger); err != nil {
		logger.Error("server stopped", "error", err)
		os.Exit(1)
	}
}

func run(logger *slog.Logger) error {
	databaseURL := os.Getenv("DATABASE_URL")
	if databaseURL == "" {
		return errors.New("DATABASE_URL is required")
	}
	addr := os.Getenv("APP_ADDR")
	if addr == "" {
		addr = ":8080"
	}

	store, err := db.Open(databaseURL)
	if err != nil {
		return err
	}
	defer store.Close()

	ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
	defer cancel()
	if err := store.Ping(ctx); err != nil {
		return err
	}

	h, err := handler.New(store, logger)
	if err != nil {
		return err
	}
	server := &http.Server{
		Addr:              addr,
		Handler:           h.Routes(),
		ReadHeaderTimeout: 5 * time.Second,
		ReadTimeout:       10 * time.Second,
		WriteTimeout:      15 * time.Second,
		IdleTimeout:       60 * time.Second,
		MaxHeaderBytes:    1 << 20,
	}

	shutdownCtx, stop := signal.NotifyContext(context.Background(), os.Interrupt, syscall.SIGTERM)
	defer stop()
	go func() {
		<-shutdownCtx.Done()
		ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
		defer cancel()
		if err := server.Shutdown(ctx); err != nil {
			logger.Error("graceful shutdown failed", "error", err)
		}
	}()

	logger.Info("server listening", "address", addr)
	if err := server.ListenAndServe(); err != nil && !errors.Is(err, http.ErrServerClosed) {
		return err
	}
	return nil
}