#!/bin/sh
## Do things with a YouTube URL.
## Config:
TERMINAL=alacritty
DOWNLOAD_DIR=~/videos/youtube
PAGER="rofi -location 2 -width 41 -e"
YOUTUBE_REGEX=".*((https?\:\/\/)?(www\.)?(youtube\.com|youtu\.?be)\/.+)$"


## Exit codes
NO_YOUTUBE_URL=3
NO_ACTION=4


## Get action for a single URL
get_action_single() {
	action=$(dmenu -p "yt-player" << EOF
1. watch in player
2. listen in player
3. download video
4. download audio
5. print info
EOF
	)
	echo "$action" | cut -d'.' -f1
}


## Get action for multiple URLs
get_action_multi() {
	# TODO: implement
}


## Check if url is a youtube url
check_if_youtube() {
	url="$1"
	echo $url | grep -qE "$YOUTUBE_REGEX" && return 0 || return 1
}


## Prompts user for URL
prompt_url() {
	dmenu -p "YouTube URL"
}


## Grab url from clipboard/primary selection, else get via prompt
grab_url() {
	if url=$(xclip -o -selection clipboard 2>/dev/null || echo) && check_if_youtube $url; then
	elif url=$(xclip -o 2>/dev/null || echo) && check_if_youtube $url; then
	elif url=$(grab_url_stdin) && check_if_youtube $url; then
	elif url=$(prompt_url) && check_if_youtube $url; then
	else
		exit $NO_YOUTUBE_URL
	fi

	echo $url
}


## Extract URL from stdin
grab_url_stdin() {
	sed -nE "s/$YOUTUBE_REGEX/\1/p"
}


## Get title, description, and duration of URL
get_info() {
	url="$1"
	info=$(youtube-dl --get-title --get-description --get-duration $url)
	title=$(echo "$info" | head -n 1)
	description=$(echo "$info" | sed '1d;$d')
	duration=$(echo "$info" | tail -n 1)
	printf "(%s) %s\n\n%s" "$duration" "$title" "$description"
}


## Download video
download_video() {
	url="$1"
	info=$(get_info $url)
	notify-send "Downloading video..." "$info" &
	youtube-dl \
		-q \
		--add-metadata \
		-o "$DOWNLOAD_DIR/%(title)s_%(id)s.%(ext)s" \
		$url && notify-send "Video download done." "$info" &
}


## Download audio
download_audio() {
	url="$1"
	info=$(get_info $url)
	notify-send "Downloading audio..." "$info"
	youtube-dl \
		-q \
		--add-metadata \
		-o "$DOWNLOAD_DIR/%(title)s_%(id)s.%(ext)s" \
		-x \
		--audio-format flac \
		--audio-quality 0 \
		$url && notify-send "Audio download done." "$info" &
}


## Play video
play_video() {
	url="$1"
	notify-send "Playing video..." "$(get_info $url)" &
	mpv --no-terminal --geometry=25%-10-40 --title="Streaming from YouTube" $url &
}


## Play audio
play_audio() {
	url="$1"
	notify-send "Playing audio..." "$(get_info $url)" &
	$TERMINAL -t "Streaming from YouTube" -e mpv --no-video $url &
}


## Print info with specified pager
print_info() {
	url="$1"
	info=$(get_info $url)
	$PAGER "$info"
}


## Main
mkdir -p "$DOWNLOAD_DIR"
url=$(grab_url)

case "$(get_action_single)" in
	5)
		print_info $url
		;;
	1)
		play_video $url
		;;
	2)
		play_audio $url
		;;
	3)
		download_video $url
		;;
	4)
		download_audio $url
		;;
	*)
		exit $NO_ACTION
esac