package commands

import (
	"bufio"
	"errors"
	"fmt"
	"net/url"
	"os"
	"os/signal"
	"path/filepath"
	"syscall"

	"github.com/gorilla/websocket"
	"github.com/manifoldco/promptui"
	"github.com/pion/webrtc/v3"
	"github.com/urfave/cli/v2"

	"github.com/livekit/livekit-server/cmd/cli/client"
	"github.com/livekit/livekit-server/pkg/logger"
)

var (
	RTCCommands = []*cli.Command{
		{
			Name:   "join",
			Action: joinRoom,
			Flags: []cli.Flag{
				roomFlag,
				rtcHostFlag,
				&cli.StringFlag{
					Name:  "token",
					Usage: "room token, not required in dev mode",
				},
				&cli.StringFlag{
					Name:     "name",
					Usage:    "name of participant",
					Required: true,
				},
				&cli.StringFlag{
					Name:  "audio",
					Usage: "an ogg file to publish upon connection",
				},
				&cli.StringFlag{
					Name:  "video",
					Usage: "an ivf file to publish upon connection",
				},
			},
		},
	}
)

func joinRoom(c *cli.Context) error {
	u, err := url.Parse(c.String("host") + "/rtc")
	if err != nil {
		return err
	}

	v := url.Values{}
	v.Set("room_id", c.String("room-id"))
	v.Set("token", c.String("token"))
	v.Set("name", c.String("name"))
	u.RawQuery = v.Encode()

	log := logger.GetLogger()

	log.Infow("connecting to Websocket signal", "url", u.String())
	conn, _, err := websocket.DefaultDialer.Dial(u.String(), nil)
	if err != nil {
		return err
	}
	defer conn.Close()

	rc, err := client.NewRTCClient(conn)
	if err != nil {
		return err
	}

	handleSignals(rc)

	// add tracks if needed
	audioFile := c.String("audio")
	videoFile := c.String("video")
	if audioFile != "" {
		rc.AddTrack(audioFile, webrtc.RTPCodecTypeAudio, "audio", filepath.Base(audioFile))
	}
	if videoFile != "" {
		rc.AddTrack(videoFile, webrtc.RTPCodecTypeVideo, "video", filepath.Base(videoFile))
	}

	// start loop to detect input
	go func() {
		for {
			r := bufio.NewReader(os.Stdin)
			_, _, err := r.ReadLine()
			if err != nil {
				return
			}

			// pause client output and wait
			rc.PauseLogs()

			err = handleCommand(rc)
			if err != nil {
				log.Errorw("could not handle command", "err", err)
			}

			rc.ResumeLogs()
		}
	}()

	return rc.Run()
}

func handleCommand(rc *client.RTCClient) error {
	cmdPrompt := promptui.Select{
		Label: "select command",
		Items: []string{
			"add video",
			"add audio",
			//"add data",
			//"send data",
			"remove track",
		},
	}

	idx, _, err := cmdPrompt.Run()
	if err != nil {
		return err
	}

	switch idx {
	case 0:
		return handleAddMedia(rc, false)
	case 1:
		return handleAddMedia(rc, true)
	default:
		return errors.New("unimplemented command")
	}
	return nil
}

func handleAddMedia(rc *client.RTCClient, isAudio bool) error {
	fileType := "vp8, h264"
	codecType := webrtc.RTPCodecTypeVideo
	if isAudio {
		fileType = "opus"
		codecType = webrtc.RTPCodecTypeAudio
	}
	// get media location
	p := promptui.Prompt{
		Label: fmt.Sprintf("media path (%s)", fileType),
		Validate: func(s string) error {
			s = ExpandUser(s)
			// ensure it exists
			st, err := os.Stat(s)
			if err != nil {
				return err
			}
			if st.IsDir() {
				return errors.New("cannot be a directory")
			}
			return nil
		},
	}

	mediaPath, err := p.Run()
	if err != nil {
		return err
	}

	mediaPath = ExpandUser(mediaPath)

	// TODO: see what the ID should be
	err = rc.AddTrack(mediaPath, codecType, codecType.String(), filepath.Base(mediaPath))
	if err != nil {
		return err
	}
	fmt.Printf("added %s track: %s\n", codecType.String(), mediaPath)

	if isAudio {
		return nil
	}

	// for video files, also look for the .ogg at the same path
	videoExt := filepath.Ext(mediaPath)
	if len(videoExt) == 0 {
		return nil
	}

	audioPath := mediaPath[0:len(mediaPath)-len(videoExt)] + ".ogg"
	if _, err = os.Stat(audioPath); err == nil {
		err = rc.AddTrack(audioPath, webrtc.RTPCodecTypeAudio, codecType.String(), filepath.Base(audioPath))
		if err != nil {
			fmt.Printf("added audio track: %s\n", audioPath)
		}
	}
	return err
}

func handleSignals(rc *client.RTCClient) {
	// signal to stop client
	sigChan := make(chan os.Signal, 1)
	signal.Notify(sigChan, syscall.SIGINT, syscall.SIGTERM, syscall.SIGQUIT)

	go func() {
		sig := <-sigChan
		logger.GetLogger().Infow("exit requested, shutting down", "signal", sig)
		rc.Stop()
	}()
}