main.go

package main

import (
	"flag"
	"fmt"
	"os"
	"regexp"
	"strings"

	"github.com/Gotham25/hotstar-dl/utils"
)

//Build version info vars injected by goreleaser
var version string
var commit string
var date string

//flag descriptions
var helpFlagDesc = "Prints this help and exit"
var listFormatsFlagDesc = "List available video formats for given url"
var playlistFlagDesc = "Video range to download from playlist"
var formatFlagDesc = "Video format to download video in specified resolution"
var ffmpegPathFlagDesc = "Location of the ffmpeg binary(absolute path)"
var metadataFlagDesc = "Add metadata to the video file"
var outputFileNameFlagDesc = "Output file name"
var titleFlagDesc = "Prints video title and exit"
var descriptionFlagDesc = "Prints video description and exit"
var versionFlagDesc = "Prints version info and exits"

//flag declarations
var helpFlag = flag.Bool("help", false, helpFlagDesc)
var listFormatsFlag = flag.Bool("list", false, listFormatsFlagDesc)
var formatFlag = flag.String("format", "", formatFlagDesc)
var playlistFlag = flag.String("playlist", "", playlistFlagDesc)
var ffmpegPathFlag = flag.String("ffmpeg-location", "", ffmpegPathFlagDesc)
var metadataFlag = flag.Bool("add-metadata", false, metadataFlagDesc)
var outputFileNameFlag = flag.String("output", "", outputFileNameFlagDesc)
var titleFlag = flag.Bool("get-title", false, titleFlagDesc)
var descriptionFlag = flag.Bool("get-description", false, descriptionFlagDesc)
var versionFlag = flag.Bool("version", false, versionFlagDesc)

func init() {
	//shorthand notations
	flag.BoolVar(helpFlag, "h", false, helpFlagDesc)
	flag.BoolVar(listFormatsFlag, "l", false, listFormatsFlagDesc)
	flag.StringVar(formatFlag, "f", "", formatFlagDesc)
	flag.StringVar(playlistFlag, "p", "", playlistFlagDesc)
	flag.BoolVar(metadataFlag, "m", false, metadataFlagDesc)
	flag.StringVar(outputFileNameFlag, "o", "", outputFileNameFlagDesc)
	flag.BoolVar(titleFlag, "t", false, titleFlagDesc)
	flag.BoolVar(descriptionFlag, "i", false, descriptionFlagDesc)
	flag.BoolVar(versionFlag, "v", false, versionFlagDesc)

	//custom flag usage
	flag.Usage = func() {
		fmt.Fprintf(os.Stdout, "Usage: %s [OPTIONS] URL\n\n", os.Args[0])
		fmt.Println("Options:")
		fmt.Fprintf(os.Stdout, "-h, --help\t\t%s\n", helpFlagDesc)
		fmt.Fprintf(os.Stdout, "-l, --list\t\t%s\n", listFormatsFlagDesc)
		fmt.Fprintf(os.Stdout, "-p, --playlist\t\t%s\n", playlistFlagDesc)
		fmt.Fprintf(os.Stdout, "-f, --format\t\t%s\n", formatFlagDesc)
		fmt.Fprintf(os.Stdout, "--ffmpeg-location\t%s\n", ffmpegPathFlagDesc)
		fmt.Fprintf(os.Stdout, "-m, --add-metadata\t%s\n", metadataFlagDesc)
		fmt.Fprintf(os.Stdout, "-t, --get-title\t\t%s\n", titleFlagDesc)
		fmt.Fprintf(os.Stdout, "-i, --get-description\t%s\n", descriptionFlagDesc)
		fmt.Fprintf(os.Stdout, "-o, --output\t\t%s\n", outputFileNameFlagDesc)
		fmt.Fprintf(os.Stdout, "-v, --version\t\t%s\n", versionFlagDesc)
		os.Exit(0)
		//flag.PrintDefaults()
	}
}

func isDashVideoFormatCode(formatCode string) bool {
	if strings.HasPrefix(formatCode, "dash-audio-") {
		return true
	} else if strings.HasPrefix(formatCode, "dash-video-") {
		return true
	} else {
		return false
	}
}

func hasValidFormatPrefix(formatCode string) bool {
	if strings.HasPrefix(formatCode, "hls-") {
		return true
	} else if isDashVideoFormatCode(formatCode) {
		return true
	}
	return false
}

func isValidPlaylistFormat(playlistFormat string) (string, string, bool) {
	var playlistFormatRegex = regexp.MustCompile(`^(?P<startRange>\d*)-(?P<endRange>\d*)$`)
	if playlistFormatRegex.MatchString(playlistFormat) {
		match := utils.ReSubMatchMap(playlistFormatRegex, playlistFormat)
		return match["startRange"], match["endRange"], true
	}
	return "", "", false
}

func handlePlaylistURL(playlistID string) {
	var playlistStartRange, playlistEndRange string
	var isValidPlaylist bool

	if *playlistFlag != "" {
		playlistStartRange, playlistEndRange, isValidPlaylist = isValidPlaylistFormat(*playlistFlag)
		if !isValidPlaylist {
			fmt.Printf("\nInvalid playlist format '%s' specified. Should be of form <number>-<number>. Eg like 3-7 (or) 8- (or) -5 (or) -", *playlistFlag)
			os.Exit(-1)
		}
	}

	if *listFormatsFlag || *titleFlag || *descriptionFlag {
		utils.ListOrDownloadPlaylistVideoFormats(playlistID, *titleFlag, *descriptionFlag, playlistStartRange, playlistEndRange, false, *formatFlag, *ffmpegPathFlag, *outputFileNameFlag, *metadataFlag, false)
	} else if *formatFlag != "" {
		if !hasValidFormatPrefix(*formatFlag) {
			fmt.Println("Invalid format specified")
			os.Exit(-1)
		} else {
			if isDashVideoFormatCode(*formatFlag) {
				utils.ListOrDownloadPlaylistVideoFormats(playlistID, *titleFlag, *descriptionFlag, playlistStartRange, playlistEndRange, true, *formatFlag, *ffmpegPathFlag, *outputFileNameFlag, *metadataFlag, true)
			} else {
				utils.ListOrDownloadPlaylistVideoFormats(playlistID, *titleFlag, *descriptionFlag, playlistStartRange, playlistEndRange, true, *formatFlag, *ffmpegPathFlag, *outputFileNameFlag, *metadataFlag, false)
			}
		}
	} else {
		utils.ListOrDownloadPlaylistVideoFormats(playlistID, *titleFlag, *descriptionFlag, playlistStartRange, playlistEndRange, true, *formatFlag, *ffmpegPathFlag, *outputFileNameFlag, *metadataFlag, false)
	}
}

func handleNonPlaylistURL(videoURL, videoID string) {
	if *listFormatsFlag || *titleFlag || *descriptionFlag {
		//list video formats
		utils.ListVideoFormats(videoURL, videoID, nil, *titleFlag, *descriptionFlag)
	} else if *formatFlag != "" {
		if !hasValidFormatPrefix(*formatFlag) {
			fmt.Println("Invalid format specified")
			os.Exit(-1)
		} else {
			if isDashVideoFormatCode(*formatFlag) {
				utils.DownloadAudioOrVideo(videoURL, videoID, *formatFlag, *ffmpegPathFlag, *outputFileNameFlag, *metadataFlag, true)
			} else {
				utils.DownloadAudioOrVideo(videoURL, videoID, *formatFlag, *ffmpegPathFlag, *outputFileNameFlag, *metadataFlag, false)
			}
		}
	} else {
		//Fallback to best (or) least format identified so far
		utils.DownloadAudioOrVideo(videoURL, videoID, *formatFlag, *ffmpegPathFlag, *outputFileNameFlag, *metadataFlag, false)
	}
}

func main() {

	flag.Parse()
	flagCount := len(flag.Args())
	if *helpFlag {
		flag.Usage()
	} else if *versionFlag {
		fmt.Printf("Version : %s\ngit commit SHA : %s \nBuilt on : %s\n", version, commit, date)
	} else if flagCount == 0 {
		fmt.Println("Must provide atleast one url at end")
		flag.Usage()
		os.Exit(-1)
	} else if flagCount > 1 {
		fmt.Println("URL must be provided at end before options")
		flag.Usage()
		os.Exit(-1)
	} else if videoURL := flag.Args()[0]; videoURL != "" {

		videoURL = utils.GetParsedVideoURL(videoURL)

		isValidURL, videoOrPlaylistID, isPlaylistID := utils.IsValidHotstarURL(videoURL)
		if isValidURL {
			if isPlaylistID {
				handlePlaylistURL(videoOrPlaylistID)

			} else {
				handleNonPlaylistURL(videoURL, videoOrPlaylistID)
			}
		} else {
			fmt.Println("Invalid hotstar url. Please enter a valid one")
			os.Exit(-1)
		}

	} else {
		fmt.Println("Invalid args specified")
		flag.Usage()
	}

}