#!/usr/bin/env bash
# ┬┌─┬ ┬┌┐┌┌─┐┌┬┐
# ├┴┐│ ││││└─┐ │
# ┴ ┴└─┘┘└┘└─┘ ┴
# Created by Siddharth Dushantha
#
# Dependencies: sxiv, imagemagick, bash, ffmpeg, mpc, jq


VERSION=1.2.3
COVER=/tmp/kunst.jpg
MUSIC_DIR=~/Music/
SIZE=250x250


show_help() {
	echo "usage: kunst [-h] [--size "px"] [--music_dir "path/to/dir"] [--silent] [--version]"
	echo " "
	echo "┬┌─┬ ┬┌┐┌┌─┐┌┬┐"
	echo "├┴┐│ ││││└─┐ │"
	echo "┴ ┴└─┘┘└┘└─┘ ┴"
	echo "Download and display album art or display embedded album art"
	echo " "
	echo "optional arguments:"
	echo "   -h, --help            show this help message and exit"
	echo "   --size                what size to display the album art in"
	echo "   --music_dir           the music directory which MPD plays from"
	echo "   --silent              dont show the output"
	echo "   --version             show the version of kunst you are using"
}


# Parse the arguments
options=$(getopt -o h --long size:,music_dir:,version,silent,help -- "$@")
eval set -- "$options"

while true; do
    case "$1" in
        --size)
            shift;
            SIZE=$1
            ;;
        --music_dir)
            shift;
            MUSIC_DIR=$1
            ;;
        -h|--help)
		    show_help
			exit
            ;;
		--version)
		    echo $VERSION
			exit
			;;
        --silent)
            SILENT=true
            ;;
        --)
            shift
            break
            ;;
    esac
    shift
done

# This is a base64 endcoded image which will be used if
# the file does not have an emmbeded album art.
# The image is an image of a music note
read -d '' MUSIC_NOTE << EOF
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
EOF


is_connected() {
	# Check if internet is connected. We are using api.deezer.com to test
	# if the internet is connected because if api.deezer.com is down or
	# the internet is not connected this script will work as expected
	if ping -q -c 1 -W 1 api.deezer.com >/dev/null; then
		connected=true
	else
        if [ ! $SILENT ];then
            echo "kunst: unable to check online for the album art"
        fi
		connected=false
	fi
}


get_cover_online() {
	# Check if connected to internet
	is_connected

	if [ $connected == false ];then
		ARTLESS=true
		return
	fi

	# Try to get the album cover online from api.deezer.com
	API_URL="http://api.deezer.com/search/autocomplete?q=$(mpc current)" && API_URL=${API_URL//' '/'%20'}

	# Extract the albumcover from the json returned
	#IMG_URL=$(curl -s "$API_URL" | jq -r '.playlists.data[0] | .picture_big')
	IMG_URL=$( curl -s "$API_URL" | jq -r '.tracks.data[0].album.cover_big')
	if [ "$IMG_URL" = '' ] || [ "$IMG_URL" = 'null' ];then
        if [ ! $SILENT ];then
            echo "error: cover not found online"
        fi
		ARTLESS=true
	else
        if [ ! $SILENT ];then
            echo "kunst: cover found online"
        fi
		curl -o $COVER -s $IMG_URL
        eyeD3 --add-image $COVER:FRONT_COVER $MUSIC_DIR$(mpc current -f %file%)
		ARTLESS=false
	fi

}

write_tag(){
    #writes down song data if absent
    #uses eyeD3
    eyeD3 -v ~/Music/$(mpc current -f %file%)  | egrep "None|null" && tags="0" || tags="1"
    if  [ $tags -eq "0"  ] ;then
        echo "Some tags missing"
	    API_URL="http://api.deezer.com/search/autocomplete?q=$(mpc current)" && API_URL=${API_URL//' '/'%20'}
        #album
        echo "writing down album name"
        eyeD3 -A "$( curl -s "$API_URL" | jq -r '.tracks.data[0].album.title')" $MUSIC_DIR$(mpc current -f %file%)
        #album artist
        echo "writing down album artist"
        eyeD3 -b "$( curl -s "$API_URL" | jq -r '.tracks.data[0].artist.name')"  $MUSIC_DIR$(mpc current -f %file%)
    else
        echo "All tags are present"
    fi

}

update_cover() {
	# Extract the album art from the mp3 file and dont show the messsy
	# output of ffmpeg
	ffmpeg -i "$MUSIC_DIR$(mpc current -f %file%)" $COVER -y &> /dev/null

	# Get the status of the previous command
	STATUS=$?

	# Check if the file has a embbeded album art
	if [ $STATUS -eq 0 ];then
        if [ ! $SILENT ];then
            echo "kunst: extracted album art"
        fi
		ARTLESS=false
	else
        DIR="$MUSIC_DIR$(dirname "$(mpc current -f %file%)")"
        if [ ! $SILENT ];then
            echo "kunst: inspecting $DIR"
        fi

		# Check if there is an album cover/art in the folder.
		# Look at issue #9 for more details
        for CANDIDATE in "$DIR/cover."{png,jpg}; do
            if [ -f "$CANDIDATE" ]; then
                STATUS=0
                ARTLESS=false
                convert "$CANDIDATE" $COVER
                if [ ! $SILENT ];then
                    echo "kunst: found cover.png"
                fi
            fi
        done
    fi

	if [ $STATUS -ne 0 ];then
        if [ ! $SILENT ];then
            echo "error: file does not have an album art"
        fi
		get_cover_online
	fi

	# Resize the image to 250x250
	if [ $ARTLESS == false ]; then
		convert $COVER -resize $SIZE $COVER
        if [ ! $SILENT ];then
            echo "kunst: resized album art to $SIZE"
        fi
	fi

}

pre_exit() {
	# Get the proccess ID of kunst and kill it.
    # We are dumping the output of kill to /dev/null
    # because if the user quits sxiv before they
    # exit kunst, an error will be shown
    # from kill and we dont want that
	kill -9 $(cat /tmp/kunst.pid) &> /dev/null

}

main() {

	# Flag to run some commands only once in the loop
	FIRST_RUN=true
	while true; do
		update_cover
        write_tag
		if [ $ARTLESS == true ];then
			# Dhange the path to COVER because the music note
			# image is a png not jpg
			COVER=/tmp/kunst.jpg

			# Decode the base64 encoded image and save it
			# to /tmp/kunst.png
			echo "$MUSIC_NOTE" | base64 --decode > $COVER
		fi

        if [ ! $SILENT ];then
            echo "kunst: swapped album art to $(mpc current)"
            printf '%*s\n' "${COLUMNS:-$(tput cols)}" '' | tr ' ' -
        fi

		if [ $FIRST_RUN == true ]; then
			FIRST_RUN=false

			# Display the album art using sxiv
			sxiv -g $SIZE -b $COVER -N "Kunst" &

			# Save the process ID so that we can kill
			# sxiv when the user exits the script
			echo $! >/tmp/kunst.pid
		fi

		# Waiting for an event from mpd; play/pause/next/previous
		# this is lets kunst use less CPU :)
		mpc idle &> /dev/null
        if [ ! $SILENT ];then
            echo "kunst: received event from mpd"
        fi
	done
}

# Disable CTRL-Z because if we allowed this key press,
# then the script would exit but, sxiv would still be
# running
trap "" SIGTSTP

trap pre_exit EXIT
main