package actions

import (
	"context"
	"io"
	"net/http"
	"os"
	"os/signal"
	"path/filepath"
	"strings"
	"time"

	"git.t-juice.club/torjus/gpaste"
	"git.t-juice.club/torjus/gpaste/api"
	"git.t-juice.club/torjus/gpaste/files"
	"git.t-juice.club/torjus/gpaste/users"
	"github.com/google/uuid"
	"github.com/urfave/cli/v2"
	"go.uber.org/zap"
	"go.uber.org/zap/zapcore"
)

func ActionServe(c *cli.Context) error {
	configPath := "gpaste-server.toml"
	if c.IsSet("config") {
		configPath = c.String("config")
	}

	var (
		cfg *gpaste.ServerConfig
		r   io.ReadCloser
	)

	r, err := os.Open(configPath)
	if err != nil {
		cfg = &gpaste.ServerConfig{
			LogLevel:      "INFO",
			URL:           "localhost:8080",
			ListenAddr:    ":8080",
			SigningSecret: "TODO: CHANGE THIS LOL",
			Store: &gpaste.ServerStoreConfig{
				Type: "memory",
			},
		}
	} else {
		defer r.Close()
		cfg, err = gpaste.ServerConfigFromReader(r)
		if err != nil {
			if err != nil {
				return cli.Exit(err, 1)
			}
		}
	}
	// Setup loggers
	rootLogger := getRootLogger(cfg.LogLevel)
	serverLogger := rootLogger.Named("SERV")
	accessLogger := rootLogger.Named("ACCS")

	// Setup contexts for clean shutdown
	rootCtx, rootCancel := signal.NotifyContext(context.Background(), os.Interrupt)
	defer rootCancel()

	httpCtx, httpCancel := context.WithCancel(rootCtx)
	defer httpCancel()

	httpShutdownCtx, httpShutdownCancel := context.WithCancel(context.Background())
	defer httpShutdownCancel()

	// Setup stores
	// Files
	fileStore, fileClose, err := getFileStore(cfg)
	if err != nil {
		return err
	}

	defer fileClose() // nolint: errcheck

	// Users
	userStore, userClose, err := getUserStore(cfg)
	if err != nil {
		return err
	}

	defer userClose() // nolint: errcheck

	if userList, err := userStore.List(); err != nil {
		serverLogger.Panicw("Error checking userstore for users.", "error", err)
	} else if len(userList) < 1 {
		admin := users.User{
			Username: "admin",
			Role:     users.RoleAdmin,
		}
		password := uuid.NewString()
		if err := admin.SetPassword(password); err != nil {
			serverLogger.DPanic("Error setting admin-user password.", "error", err)
		}

		serverLogger.Warnw("Created admin-user.", "username", admin.Username, "password", password)
	}

	// Auth
	auth := gpaste.NewAuthService(userStore, []byte(cfg.SigningSecret))

	go func() {
		srv := api.NewHTTPServer(cfg)
		srv.Users = userStore
		srv.Files = fileStore
		srv.Addr = cfg.ListenAddr
		srv.Logger = serverLogger
		srv.AccessLogger = accessLogger
		srv.Auth = auth

		// Wait for cancel
		go func() {
			<-httpCtx.Done()

			timeoutCtx, cancel := context.WithTimeout(context.Background(), 10*time.Second) // nolint: gomnd
			defer cancel()

			_ = srv.Shutdown(timeoutCtx)
		}()
		serverLogger.Infow("Starting HTTP server.", "addr", cfg.ListenAddr)

		if err := srv.ListenAndServe(); err != nil && err != http.ErrServerClosed {
			serverLogger.Errorw("Error during shutdown.", "error", err)
		}

		serverLogger.Infow("HTTP server shutdown complete.", "addr", cfg.ListenAddr)
		httpShutdownCancel()
	}()
	<-httpShutdownCtx.Done()

	return nil
}

func getRootLogger(level string) *zap.SugaredLogger {
	logEncoderConfig := zap.NewProductionEncoderConfig()
	logEncoderConfig.EncodeCaller = zapcore.ShortCallerEncoder
	logEncoderConfig.EncodeLevel = zapcore.CapitalColorLevelEncoder
	logEncoderConfig.EncodeTime = zapcore.ISO8601TimeEncoder
	logEncoderConfig.EncodeDuration = zapcore.StringDurationEncoder

	rootLoggerConfig := &zap.Config{
		Level:            zap.NewAtomicLevelAt(zap.DebugLevel),
		OutputPaths:      []string{"stdout"},
		ErrorOutputPaths: []string{"stdout"},
		Encoding:         "console",
		EncoderConfig:    logEncoderConfig,
		DisableCaller:    true,
	}

	switch strings.ToUpper(level) {
	case "DEBUG":
		rootLoggerConfig.DisableCaller = false
		rootLoggerConfig.Level = zap.NewAtomicLevelAt(zap.DebugLevel)
	case "INFO":
		rootLoggerConfig.Level = zap.NewAtomicLevelAt(zap.InfoLevel)
	case "WARN", "WARNING":
		rootLoggerConfig.Level = zap.NewAtomicLevelAt(zap.WarnLevel)
	case "ERR", "ERROR":
		rootLoggerConfig.Level = zap.NewAtomicLevelAt(zap.ErrorLevel)
	}

	rootLogger, err := rootLoggerConfig.Build()
	if err != nil {
		panic(err)
	}

	return rootLogger.Sugar()
}

// nolint: ireturn
func getUserStore(cfg *gpaste.ServerConfig) (users.UserStore, func() error, error) {
	closer := func() error { return nil }

	switch cfg.Store.Type {
	case "memory":
		return users.NewMemoryUserStore(), closer, nil

	case "fs":
		path := filepath.Join(cfg.Store.FS.Dir, "gpaste-users.db")

		bs, err := users.NewBoltUserStore(path)
		if err != nil {
			return nil, closer, cli.Exit("error setting up user store", 1)
		}

		return bs, bs.Close, nil

	default:
		return nil, closer, cli.Exit("no userstore configured", 1)
	}
}

// nolint: ireturn
func getFileStore(cfg *gpaste.ServerConfig) (files.FileStore, func() error, error) {
	closer := func() error { return nil }

	switch cfg.Store.Type {
	case "memory":
		return files.NewMemoryFileStore(), closer, nil

	case "fs":
		var err error

		s, err := files.NewFSFileStore(cfg.Store.FS.Dir)
		if err != nil {
			return nil, closer, cli.Exit("error setting up filestore", 1)
		}

		return s, closer, nil
	default:
		return nil, closer, cli.Exit("No store configured", 1)
	}
}