package main

import (
	"context"
	"encoding/hex"
	"errors"
	"os"
	"os/signal"

	"github.com/fasthttp/router"
	"github.com/sirupsen/logrus"
	flag "github.com/spf13/pflag"
	"github.com/valyala/fasthttp"
	"gorm.io/driver/mysql"
	"gorm.io/driver/postgres"
	"gorm.io/driver/sqlite"
	"gorm.io/gorm"

	"git.sr.ht/~gabrielgio/img"
	"git.sr.ht/~gabrielgio/img/pkg/components/auth"
	"git.sr.ht/~gabrielgio/img/pkg/components/filesystem"
	"git.sr.ht/~gabrielgio/img/pkg/components/media"
	"git.sr.ht/~gabrielgio/img/pkg/database/localfs"
	"git.sr.ht/~gabrielgio/img/pkg/database/sql"
	"git.sr.ht/~gabrielgio/img/pkg/ext"
	"git.sr.ht/~gabrielgio/img/pkg/view"
	"git.sr.ht/~gabrielgio/img/pkg/worker"
)

func main() {
	var (
		key            = flag.String("aes-key", "", "AES key, either 16, 24, or 32 bytes string to select AES-128, AES-192, or AES-256")
		dbType         = flag.String("db-type", "sqlite", "Database to be used. Choose either mysql, psql or sqlite")
		dbCon          = flag.String("db-con", "main.db", "Database string connection for given database type. Ref: https://gorm.io/docs/connecting_to_the_database.html")
		logLevel       = flag.String("log-level", "error", "Log level: Choose either trace, debug, info, warning, error, fatal or panic")
		schedulerCount = flag.Uint("scheduler-count", 10, "How many workers are created to process media files")

		// TODO: this will later be replaced by user specific root folder
		root = flag.String("root", "", "root folder for the whole application. All the workers will use it as working directory")
	)

	flag.Parse()

	l, err := logrus.ParseLevel(*logLevel)
	if err != nil {
		panic("failed to parse log level" + err.Error())
	}
	logger := logrus.New()
	logger.SetLevel(l)

	d, err := OpenDatabase(*dbType, *dbCon)
	if err != nil {
		panic("failed to parse database strings" + err.Error())
	}

	db, err := gorm.Open(d, &gorm.Config{
		Logger: ext.Wraplog(logger.WithField("context", "sql")),
	})
	if err != nil {
		panic("failed to connect database: " + err.Error())
	}

	if err = sql.Migrate(db); err != nil {
		panic("failed to migrate database: " + err.Error())
	}

	hexKey, err := hex.DecodeString(*key)
	if err != nil {
		panic("failed to decode key database: " + err.Error())
	}

	r := router.New()
	r.GET("/static/{filepath:*}", ext.FileServer(img.StaticFS, "static/"))

	authMiddleware := ext.NewAuthMiddleware(hexKey, logger.WithField("context", "auth"))
	logMiddleware := ext.NewLogMiddleare(logger.WithField("context", "http"))

	extRouter := ext.NewRouter(r)
	extRouter.AddMiddleware(logMiddleware.HTTP)
	extRouter.AddMiddleware(authMiddleware.LoggedIn)
	extRouter.AddMiddleware(ext.HTML)

	scheduler := worker.NewScheduler(*schedulerCount)

	// repository
	var (
		userRepository       = sql.NewUserRepository(db)
		settingsRepository   = sql.NewSettingsRespository(db)
		fileSystemRepository = localfs.NewFileSystemRepository(*root)
		mediaRepository      = sql.NewMediaRepository(db)
	)

	//TODO: remove later
	userRepository.EnsureAdmin(context.Background())

	// controller
	var (
		userController       = auth.NewController(userRepository, hexKey)
		fileSystemController = filesystem.NewController(fileSystemRepository)
	)

	// view
	for _, v := range []view.View{
		view.NewAuthView(userController),
		view.NewFileSystemView(*fileSystemController, settingsRepository),
		view.NewSettingsView(settingsRepository, userRepository),
		view.NewMediaView(mediaRepository),
	} {
		v.SetMyselfIn(extRouter)
	}

	// processors
	var (
		fileScanner = worker.NewFileScanner(*root, mediaRepository)
		exifScanner = worker.NewEXIFScanner(mediaRepository)
	)

	// worker
	var (
		serverWorker = worker.NewServerWorker(&fasthttp.Server{Handler: r.Handler})
		fileWorker   = worker.NewWorkerFromChanProcessor[string](fileScanner, scheduler)
		exifWorker   = worker.NewWorkerFromBatchProcessor[*media.Media](
			exifScanner,
			scheduler,
			logrus.WithField("context", "exif scanner"),
		)
	)

	pool := worker.NewWorkerPool()
	pool.AddWorker("http server", serverWorker)
	pool.AddWorker("exif scanner", exifWorker)
	pool.AddWorker("file scanner", fileWorker)

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

	pool.Start(ctx)
}

func OpenDatabase(dbType string, dbConn string) (gorm.Dialector, error) {
	switch dbType {
	case "sqlite":
		return sqlite.Open(dbConn), nil
	case "psql":
		return postgres.Open(dbConn), nil
	case "mysql":
		return mysql.Open(dbConn), nil
	default:
		return nil, errors.New("No valid db type given")
	}
}