#!/usr/bin/env bash

# Requires:
# * curl
# * fzf | rofi
# * jq
# * youtube-dl
# * hq | pup (recomended, although optional)

rofi="auto"

ttyecho(){
	# Same as echo but always to tty
	echo "$@" > /dev/tty
}

urlencodespecial() {
	# urlencode <string>
	old_lc_collate=$LC_COLLATE
	LC_COLLATE=C
	local length="${#1}"
	for (( i = 0; i < length; i++ )); do
		local c="${1:i:1}"
		case "$c" in
			[a-zA-Z0-9.~_-]) printf "$c" ;;
			' ') printf "+" ;;
			*) printf '%%%02X' "'$c" ;;
		esac
	done
	LC_COLLATE=$old_lc_collate
}

forceread(){
	# Read but always from tty and will keep asking until a non-empty value is
	# given
	# First param is given is prompt
	local answer=""
	local first="true"
	while [ -z "$answer" ]; do
		[ "$first" == "true" ] || ttyecho "Please provide an answer"
		first="false"
		ttyecho -n "$1: "
		read answer < /dev/tty
	done
	echo "$answer"
}

useRofi(){
	[ "$rofi" = "yes" ] && return 0
	local isxclient=$( readlink /dev/fd/2 | grep -q 'tty' && [[ -n $DISPLAY ]] ; echo $? )
	if [[ ! -t 2  || $isxclient == "0" ]]; then
		return 0
	else
		return 1
	fi
}

getSearchTerm(){
	if useRofi; then
		# Rofi can't reload the suggestions so just display a search box
		echo "" | rofi -dmenu -lines 0
	else
		# Uses fzf to get a search term
		# It will filter suggestions using youtube's autocomplete
		export -f getSearchSuggestions
		export -f urlencodespecial
		echo "" | fzf --bind 'change:reload:bash -c  "getSearchSuggestions {q}" || true' \
			--header="Search Suggestions" \
			--phony \
			--height=50% --layout=reverse
	fi
}

getSearchSuggestions(){
	# Takes a query and outputs the search suggestions that youtube makes
	query="$(urlencodespecial "$1")"
	curl "https://clients1.google.com/complete/search?client=youtube&hl=en&gl=gb&gs_rn=64&gs_ri=youtube&ds=yt&cp=5&gs_id=4e&q=$query&xhr=t&xssi=t" |
		tail -n 1 | jq -r '.[1][][0]'
}

performSearch(){
	# Returns the json object yt gives us
	local raw="$1"
	local url="https://www.youtube.com/results?search_query=$(urlencodespecial "$raw")"
	if type -p hq > /dev/null; then
		curl -s "$url" | hq script data | grep 'ytInitialData' | head -n 1 | grep -o '{.*}'
	elif type -p pup > /dev/null; then
		curl -s "$url" | pup script | grep 'ytInitialData' | head -n 1 | grep -o '{.*}'
	else
		curl -s "$url" | sed -e 's/<script[^>]*>/\n/g' -e 's/<\/script>/\n/g' | grep 'ytInitialData' | head -n 1 | grep -o '{.*}'
	fi

}

extractVideoInfo(){
jq '..|.videoRenderer? | values' |
	jq -r '{title: .title.runs[0].text,
		channel: .longBylineText.runs[0].text,
		views: .shortViewCountText.simpleText,
		time: .lengthText.simpleText,
		age: .publishedTimeText.simpleText,
		video: .videoId
	}'
}

chooseVideo(){
	if useRofi; then
		( jq -r '[ .title, .channel, .views, .time, .age, .video ] | @tsv') |
			column -t -s"	" | sed $'s/  \([^ ]\)/\u00a0\\1/g' |
			rofi -dmenu
	else
		(echo -e "Title\tChannel\tViews\tTime\tAge\tId"
		jq -r '[ .title, .channel, .views, .time, .age, .video ] | @tsv') |
			column -t -s"	" | sed $'s/  \([^ ]\)/\u00a0\\1/g' |
			fzf --header-lines="1" --with-nth=1,2,3,4,5 --delimiter=$'\u00a0'
	fi
}

chooseQuality(){
	if [ -n "$1" ]; then
		videoId="$1" 
	else
		videoId="$(cat - | awk -F $'\u00a0' '{print $6}')"
	fi
	if type -p yt-dlp > /dev/null; then
		choices=" bb          Best of Both
$(yt-dlp "$videoID" -F --compat-options list-formats | sed -n '/format code/,$ p' | sed 1d)"
	else
		# 249          webm       audio only tiny   50k , webm_dash container, opus @ 50k (48000Hz), 49.85MiB
		# 250          webm       audio only tiny   60k , webm_dash container, opus @ 60k (48000Hz), 59.86MiB
		# 251          webm       audio only tiny  115k , webm_dash container, opus @115k (48000Hz), 113.94MiB
		# 140          m4a        audio only tiny  129k , m4a_dash container, mp4a.40.2@129k (44100Hz), 127.36MiB
		choices=" bb          Best of Both
$(youtube-dl "$videoId" -F | sed -n '/format code/,$ p' | sed 1d)"
	fi
	if useRofi; then
		code="$( echo "$choices" | rofi -dmenu -prompt "Quality " -m | cut -d ' ' -f 1 )"
	else
		code="$( echo "$choices" | fzf --prompt "Quality " -m | cut -d ' ' -f 1 )"
	fi

	code="$(echo "$code" | tr '\n' '+' | sed 's/+$//')"

	case "$code" in
		"bb") mpv "https://www.youtube.com/watch?v=$videoId" --ytdl-format="bestvideo+bestaudio" ;;
		*) mpv "https://www.youtube.com/watch?v=$videoId" --ytdl-format="$code" ;;
	esac
}


main(){
	local url=""
	local videoID=""
	local searchTerm=""
	while [[ "$1" = -?* ]]; do
		case "$1" in
			-u|--url)
				if [ -n "$2" ]; then
					url="$2"
					shift
				else
					url="$(cat -)"
				fi
				shift
				;;
			--rofi)
				rofi=yes
				shift
				;;
		esac
	done

	if [ -n "$url" ]; then
		case "$url" in
			# If it contains an equals sign, let's assume it's a url
			# Get the value of the v parameter
			*=*) videoID="$(echo "$url" | grep -Eo '(\?|&)v=[^?&]*' | cut -d '=' -f 2)" ;;
			# If there isn't an =, assume it is just the video ID
			*) videoID="$url"
		esac
		chooseQuality "$videoID"
	else
		searchTerm="$*"

		[ -z "$searchTerm" ] && searchTerm="$(getSearchTerm)"

		performSearch "$searchTerm" | extractVideoInfo | chooseVideo | chooseQuality

	fi
}

main "$@"