#!/bin/bash

errecho()
{
    echo -e "\e[0;31m${1}\e[0m" 1>&2
}

for dep in jq curl
do
    if [ -z $(which $dep) ]
    then
        errecho "Missing $dep package, please install"
        exit 1
    fi
done

if [ -z ${1} ]
then
    errecho "Provide a URL"
    errecho "'$0 --help' for more"
    exit 1
fi

domain=$(echo "$1" | cut -f 3 -d '/')
echo "So your domain is $domain..."

album_flag="albums"
artist_flag="artists"
look_for_id_of=""
IFS='/' read -ra chunks <<< "$1"
for chunk in "${chunks[@]}"
do
    case $chunk in
        $album_flag)
            echo "Found out it's an album..."
            look_for_id_of=$album_flag
            continue
        ;;

        $artist_flag)
            echo -n "Found out it's an artist..."
            look_for_id_of=$artist_flag
            continue
        ;;
    esac

    case $look_for_id_of in
        $album_flag)
            echo "And its ID is ${chunk}..."
            response=$(curl -X GET "https://${domain}/api/v1/tracks/?album=${chunk}&ordering=creation_date&page=1&page_size=16&scope=all" -H  "accept: application/json" | jq .)
            echo "${response}" | jq '.results' | jq -c '.[]' | while read song
            do
                echo "${song}" | jq '.uploads' | jq -c '.[]' | while read upload
                do
                    extension=$(echo ${upload} | jq -r '.extension')
                    folder=$(echo ${song} | jq -r '.album.title' | sed 's#/#_#g')
                    mkdir -p "${folder}"
                    title=$(echo ${song} | jq -r '.title' | sed 's#/#_#g')
                    listen_url=$(echo ${song} | jq -r '.listen_url')
                    echo "Downloading '${title}'..."
                    curl -X GET "https://${domain}${listen_url}" -H  "accept: */*" -o "${folder}/${title}.${extension}"
                    break
                done
            done
            exit 0
        ;;

        $artist_flag)
            echo -n "And its ID is ${chunk}..."
            exit 0
        ;;
    esac
done

errecho "Invalid URL"
errecho "Should be either https://<domain>/library/albums/<ID>/ or https://<domain>/library/artists/<ID>/"
errecho "'$0 --help' for more"