#!/bin/sh

help(){
	case $1 in
		search*)
			name="search_play"
			args='"search_query"'
			description="this function first searches the $args, then opens the menu(fzf,[d|be]menu,[t|r|w]ofi) with the results,then calls the play function to play the music"
			;;
		play)
			name="play"
			args='"valid_youtube_url_or_id"'
			description="immediately plays the $args in mpv(audio only)"
			;;
		loop)
			name="loop"
			args='"print"'
			description="this function runs in a loop to play the next music if the current music is successfully finished
			this function should be put as background process or put it in startup
			passing print argument will show the progress to stdout"
			;;
		play*)
			name="play_next"
			args='"menu"'
			description="immediately plays the next song stored in $logdir/next file in mpv if argument is empty
			passing $args argument will show the $args(fzf,[d|be]menu,[t|r|w]ofi) for selecting what should be played"
			;;
		*)
			name="[ <function_name> ]"
			args="[ <function_arg> ]"
			description="
			<function_name>	<function_arg>	<function_description>

			search_play	search_query	searches first then plays the music in mpv
			play		youtube_url	plays the music in mpv
			play_next	menu(optional)	plays the next music in $logdir/next file
			loop		print(optional)	plays the next music after the current is finished (run it as background process)

			tip:
			type ${0##*/} help <function_name> to get individual help
			"
	esac
	while read -r line; do
		printf "%s\n" "$line"
	done <<-EOF

	Usage :
	${0##*/} $name $args

	Description :
	$description
	EOF
	exit 0
}

get_data(){
    curl -X POST -A "$agent" -s "$base_url/youtubei/v1/$1?key=AIzaSyC9XL3ZjWddXya6X74dJoCTL-WEYFDNX30&prettyPrint=false" -H "content-type:application/json" -H "x-youtube-client-name:67" -H "x-youtube-client-version:1.20221128.01.00" -d "$2" -b "$cookie" -e "$base_url/$3"
}

loop(){
	#this function does exactly what it says, it should run in the background, u can even put this in startup
	#it plays next song after the current song get played completely,it does nothing until u run the search_play function then this script kicks in
	#call it by script-name "loop" "print" for printing the remaining time in terminal
	#call it by script-name "loop" for anonymously
	trap "rm -f $logdir/next;exit" INT HUP TERM
	while true;do
		sleep 4
		pos=$(echo '{ "command": ["get_property", "time-remaining"]}' | socat - /tmp/mpvsocket | sed -nE 's_.*data":([^\.]*).*_\1_p')
		while [ -n "$pos" ];do
			pos=$(echo '{ "command": ["get_property", "time-remaining"]}' | socat - /tmp/mpvsocket | sed -nE 's_.*data":([^\.]*).*_\1_p')
			[ -z "$1" ] || printf "\033[2K\rnext music in $pos second(s)%s" "$(echo '{ "command": ["get_property", "pause"]}' | socat - /tmp/mpvsocket | sed -nE 's_.*data":([^,]*).*_\1_p' | sh && printf " (paused)")"
			[ -z "$pos" ] && printf "\033[2K\r\n"
			sleep 2
		done
		pos=$(echo '{ "command": ["get_property", "time-remaining"]}' | socat - /tmp/mpvsocket | sed -nE 's_.*data":([^\.]*).*_\1_p')
		[ -z "$pos" ] && pgrep -f "mpvsocket" > /dev/null && [ -n "$(cat "$logdir/next")" ] && play "$(shuf -n1 "$logdir/next")" "$1"
	done
}

play(){
	#this function does all the heavy lifting of extracting url from given videoId
	#it's also callable, u can use this function to play ur custom youtube URLs
	#call it by script-name "play" "valid_youtube_id_or_url"
	title=$(printf "%s" "$1" | cut -f1)
	id=$(printf "%s" "$1" | cut -f2 | cut -d"=" -f2 | cut -d"/" -f4 | cut -d'&' -f1)
	[ -z "$id" ] && printf "[ youtube ] Invalid link\n" && exit 1

	#get song's audio url
	random_no=$(head /dev/urandom | tr -dc '0-2' | cut -c1)
	droid_agent="com.google.android.youtube/17.49.34 (Linux; U; Android 1$random_no) gzip"
	json="{
	  \"context\": {
	    \"client\": {
	      \"clientName\": \"ANDROID\",
	      \"clientVersion\": \"17.49.34\",
	      \"androidSdkVersion\": $((random_no + 29)),
	      \"userAgent\": \"$droid_agent\",
	      \"hl\": \"en\",
	      \"timeZone\": \"UTC\",
	      \"utcOffsetMinutes\": 0
	    }
	  },
	  \"videoId\": \"$id\",
	  \"params\": \"8AEB\",
	  \"playbackContext\": {
	    \"contentPlaybackContext\": {
	      \"html5Preference\": \"HTML5_PREF_WANTS\"
	    }
	  },
	  \"contentCheckOk\": true,
	  \"racyCheckOk\": true
	}"
	
	audio_url=$(curl -X POST -A "$droid_agent" -s "https://www.youtube.com/youtubei/v1/player?key=AIzaSyA8eiZmM1FaDVjRy-df2KTyQ_vz_yYM39w&prettyPrint=false" -H "content-type:application/json" -H "x-youtube-client-name:21" -H "x-youtube-client-version:17.46.37" -d "$json" -b "$cookie" | sed -nE 's_.*itag":251,"url":"([^"]*)".*_\1_p')
	if [ -n "$2" ];then
		printf "Name >> %s\n" "$title"
		printf "videoID >> %s\n" "$id"
		printf "Audio URL >> %s\n" "$audio_url"
	fi
	
	curl -s "https://i.ytimg.com/vi/$id/hqdefault.jpg" -o - | convert - -crop 270x270+105+45 "$logdir/default.jpg" && notify-send -r 5 -i "$logdir/default.jpg" "Now Playing" "$title" -t 5000
	pgrep -f "mpvsocket" > /dev/null || (setsid -f mpv --really-quiet --input-ipc-server=/tmp/mpvsocket --idle --quiet >/dev/null && sleep 1)
	echo "{ \"command\": [\"loadfile\", \"$audio_url\", \"replace\"] }" | socat - /tmp/mpvsocket
	cut -d':' -f2 "$logdir/current" > "$logdir/prev"
	prev_id=$(cut -d'>' -f2 "$logdir/prev")
	printf "currently playing : %s >%s\n" "$title" "$id" > "$logdir/current"

	#next songs data
	json_next="{
	\"enablePersistentPlaylistPanel\": true,
	\"tunerSettingValue\": \"AUTOMIX_SETTING_NORMAL\",
	\"playlistId\": \"RDAMVM$id\",
	\"isAudioOnly\": true,
	\"context\": $(cat "$logdir/context")
	}"
	get_data "next" "$json_next" | sed 's/playlistPanelVideoRenderer/\n/g' | sed -nE 's_.*text":"(.*)"}.*longBylineText":\{"runs":\[\{"text":"([^"]*)","navigationEndpoint.*videoId":"([^"]*)".*_\1 - \2\t\3_p' | sed "/$id/d;/$prev_id/d" > "$next_data" &
	pgrep -f "yt-music loop" || setsid -f $HOME/repos_scripts/yt-music loop
}

search_play(){
	#run this if u r starting the script first time like this
	#call this by "script-name" "search_play" "search_query"
	[ -z "$1" ] && query=$(:| menu "Yt-music [Search]: ") || query="$1"
	[ -z "$query" ] && notify-send "Err.. Search query empty" -u critical -r 5 && exit 1
	curl -A "$agent" -s "$base_url/" -c "$cookie" | sed -nE 's|.*INNERTUBE_CONTEXT":(.*),"INNERTUBE_CONTEXT_CLIENT_NAME.*|\1|p' > "$logdir/context"

	json_search="{
	\"context\" : $(cat "$logdir/context"),
	\"query\": \"$query\",
	\"params\": \"EgWKAQIIAWoKEAMQBBAJEAoQBQ%3D%3D\"
	}"
	res=$(get_data "search" "$json_search" "search?q=$(printf "%s" "$1" | tr ' ' '+')" | sed 's/watchEndpoint"/\n/g' | sed -nE 's_.*videoId":"([^"]*)",.*label":"Play ([^"]*)".*_\2\t\1_p' | menu "Yt-music [Play]: ")
	[ -z "$res" ] || play "$res" "verbose"
}

play_next(){
	#call this by script-name "play_next" for playing next song immediately
	#or add "menu" after "play_next" to show menu for selecting and playing next song immediately
	#like this script-name "play_next" "menu"
	[ -z "$1" ] && play "$(shuf -n1 "$logdir/next")" "verbose" || (pgrep -f "mpvsocket" && notify-send -r 5 -i "$logdir/default.jpg" "$(cut -d">" -f1 "$logdir/current" | tr ':' '\n')" && play "$(menu "YT-music [play-next]: " < "$logdir/next")" "verbose")
}

menu(){
	bemenu --fn 'Roboto 15' -i -c -W 0.5 -B 3 -p "$1" -l 26
}

logdir="/tmp/yt-music"
base_url="https://music.youtube.com"
[ -d "$logdir" ] || mkdir "$logdir"
cookie="$logdir/cookies"
next_data="$logdir/next"
agent="Mozilla/5.0 (X11; Linux x86_64; rv:108.0) Gecko/20100101 Firefox/108.0"

#call this script by script-name "function_name" "query"
[ -z "$1" ] && help "$@"
$1 "$2" "$3"