package main

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

	"drive.local/drivev2/internal/adapters/authn"
	"drive.local/drivev2/internal/adapters/postgres"
	"drive.local/drivev2/internal/adapters/webassets"
	"drive.local/drivev2/internal/application"
	"drive.local/drivev2/internal/config"
	"drive.local/drivev2/internal/transport/httpapi"
)

var version = "dev"

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

func run() error {
	command := "serve"
	if len(os.Args) > 1 {
		command = os.Args[1]
	}

	switch command {
	case "serve":
		return serve()
	case "version":
		fmt.Println(version)
		return nil
	default:
		return fmt.Errorf("unknown command %q", command)
	}
}

func serve() error {
	cfg, err := config.FromEnvironment()
	if err != nil {
		return err
	}
	if cfg.DatabaseURL == "" {
		return errors.New("DRIVE_DATABASE_URL is required for serve")
	}

	logger := slog.New(slog.NewJSONHandler(os.Stdout, &slog.HandlerOptions{Level: cfg.LogLevel}))
	slog.SetDefault(logger)

	startupCtx, startupCancel := context.WithTimeout(context.Background(), 30*time.Second)
	defer startupCancel()
	if err := postgres.Migrate(cfg.DatabaseURL); err != nil {
		return err
	}
	store, err := postgres.Open(startupCtx, cfg.DatabaseURL)
	if err != nil {
		return err
	}
	defer store.Close()

	systemService := application.NewSystemService(store, version)
	authenticationService := application.NewAuthenticationService(
		store,
		authn.NewPasswordHasher(),
		authn.CredentialGenerator{},
		authn.SystemClock{},
	)
	server := httpapi.NewServer(cfg, logger, systemService, authenticationService, webassets.New(cfg.WebRoot))
	ctx, stop := signal.NotifyContext(context.Background(), syscall.SIGINT, syscall.SIGTERM)
	defer stop()

	errCh := make(chan error, 1)
	go func() {
		logger.Info("starting drive", "address", cfg.HTTPAddress, "version", version)
		errCh <- server.ListenAndServe()
	}()

	select {
	case err := <-errCh:
		if errors.Is(err, httpapi.ErrServerClosed) {
			return nil
		}
		return err
	case <-ctx.Done():
		shutdownCtx, cancel := context.WithTimeout(context.Background(), 20*time.Second)
		defer cancel()
		return server.Shutdown(shutdownCtx)
	}
}