#!/bin/bash
# dependencies: mpv youtube-dl fzf rofi/dmenu
# search videos and playlists on youtube and play them in mpv, without an API 
# usage:
# yt					asks for input in stdin, prompts using fzf
# yt search query		takes input from the passed arg, prompts using fzf
# yt -r					takes input and prompts using rofi ($guicmd)

agent="Mozilla/5.0 (Windows NT 10.0; rv:78.0) Gecko/20100101 Firefox/78.0"
defcmd="fzf"
guicmd="wofi -d -i"
promptcmd="$defcmd"
if [ -z "$*" ]; then 
	echo -n "Search: "
	read -r query
else
	case "$1" in
		-r) query=$(echo | $guicmd -p "Search: ")
			promptcmd="$guicmd -p Video:";;
		*) query="$*";;
	esac
fi
if [ -z "$query" ]; then exit; fi 
# sanitise the query
query=$(sed \
	-e 's|+|%2B|g'\
	-e 's|#|%23|g'\
	-e 's|&|%26|g'\
	-e 's| |+|g'\
	<<< "$query")
# fetch the results with the $query and
# delete all escaped characters
response="$(curl -s "https://www.youtube.com/results?search_query=$query" -A "$agent" |\
	sed 's|\\.||g')"
# if unable to fetch the youtube results page, inform and exit
if ! grep -q "script" <<< "$response"; then echo "unable to fetch yt"; exit 1; fi
# regex expression to match video and playlist entries from yt result page
vgrep='"videoRenderer":{"videoId":"\K.{11}".+?"text":".+?[^\\](?=")'
pgrep='"playlistRenderer":{"playlistId":"\K.{34}?","title":{"simpleText":".+?[^\"](?=")'
# grep the id and title
# return them in format id (type) title
getresults() {
	  grep -oP "$1" <<< "$response" |\
		awk -F\" -v p="$2" '{ print $1 "\t" p " " $NF}'
}
# get the list of videos/playlists and their ids in videoids and playlistids
videoids=$(getresults "$vgrep")
playlistids=$(getresults "$pgrep" "(playlist)")
# if there are playlists or videos, append them to list
[ -n "$playlistids" ] && ids="$playlistids\n"
[ -n "$videoids" ] && ids="$ids$videoids"
# url prefix for videos and playlists
videolink="https://youtu.be/"
playlink="https://youtube.com/playlist?list="
# prompt the results to user infinitely until they exit (escape)
while true; do
	clear
	echo "Choose Video/Playlist to play: "
	choice=$(echo -e "$ids" | cut -d'	' -f2 | $promptcmd) # dont show id
	if [ -z "$choice" ]; then exit; fi	# if esc-ed then exit
	id=$(echo -e "$ids" | grep -Fwm1 "$choice" | cut -d'	' -f1) # get id of choice
	echo -e "$choice\t($id)"
	case $id in
		# 11 digit id = video
		???????????) mpv "$videolink$id";;
		# 34 digit id = playlist
		??????????????????????????????????) mpv "$playlink$id";;
		*) exit ;;
	esac
done