discord download/updater script

discord-download-standalone.sh

#!/usr/bin/env bash

##
## A standalone and less opinionated version of the local user Discord installer from gitlab.com/adryd325/dotfiles
## Tested on Arch Linux, will most likely work on anything else that can run Discord.
##

tempDir=$(mktemp -d)
DOWNLOAD_ENDPOINT='https://discord.com/api/download'
DOWNLOAD_OPTIONS='?platform=linux&format=tar.gz'
function getDiscordDownloadURL {
    if [[ "$1" = "stable" ]] || [[ -z "$1" ]]; then
        printf %s%s "${DOWNLOAD_ENDPOINT}" "${DOWNLOAD_OPTIONS}"
    else
        printf %s/%s%s "${DOWNLOAD_ENDPOINT}" "$1" "${DOWNLOAD_OPTIONS}"
    fi
}

function isValidBranch {
    invalid=1
    for i in "${DISCORD_BRANCHES[@]}"; do
        if [[ "${i}" = "$1" ]]; then
            invalid=0
        fi
    done
    return "${invalid}"
}

function getDiscordName {
    branch=$1
    if [[ "${branch}" = "stable" ]]; then
        printf "Discord"
    elif [[ "${branch}" = "ptb" ]]; then
        printf "DiscordPTB"
    else
        printf "Discord%s" "${branch^}"
    fi
}

function getDiscordPrettyName {
    branch=$1
    if [[ "${branch}" = "stable" ]]; then
        printf "Discord"
    elif [[ "${branch}" = "ptb" ]]; then
        printf "Discord PTB"
    else
        printf "Discord %s" "${branch^}"
    fi
}

function getDiscordPkgName {
    branch=$1
    if [[ "${branch}" = "stable" ]]; then
        printf "discord"
    else
        printf "discord-%s" "${branch}"
    fi
}

function download {
    if [[ -x "$(command -v curl)" ]]; then
        curl -fsSL "$1" -o "$2"
        return $?
    elif [[ -x "$(command -v wget)" ]]; then
        wget -qo "$2" "$1"
        return $?
    fi
    echo "Failed to download $1. curl or wget not installed"
    return 1
}

function installBranch {
    branch=$1
    AR_LOG_PREFIX="${branch}"
    name=$(getDiscordName "${branch}")
    pkgName=$(getDiscordPkgName "${branch}")
    installationDir="${HOME}/.local/share/${name}"
    desktopFile="${HOME}/.local/share/${name}/${pkgName}.desktop"

    echo "Downloading ${branch}"
    if ! download "$(getDiscordDownloadURL "${branch}")" "${tempDir}/${name}.tar.gz"; then
        echo "Failed to download ${branch}"
        return 1
    fi

    if [[ -d "${installationDir}" ]]; then
        echo "Deleting existing ${branch} installation"
        rm -rf "${installationDir}"
    fi

    echo "Extracting ${branch}"
    if ! tar -xf "${tempDir}/${name}.tar.gz" -C "${HOME}/.local/share"; then
        echo "Failed to extract ${branch}"
        return 1
    fi

    echo "Installing ${branch}"
    
    # The new (May 2021) icon looks too big on the GNOME dock
    if [[ -x "$(command -v convert)" ]]; then
        echo "Add margin to the ${branch} icon"
        convert \
            "${installationDir}/discord.png" \
            -bordercolor Transparent \
            -compose copy \
            -border 16 \
            -resize 256x256 \
            "${installationDir}/discord.png"
    fi
    
    # Install icon
    mkdir -p "${HOME}/.local/share/icons/hicolor/256x256"
    cp -f "${installationDir}/discord.png" "${HOME}/.local/share/icons/hicolor/256x256/${pkgName}.png" &> /dev/null

    # .desktop file fixes
    sed -i "s:Exec=/usr/share/${pkgName}/${name}:Exec=\"${installationDir}/${name}\":" \
        "${desktopFile}"
    sed -i "s/StartupWMClass=discord/StartupWMClass=${name}/" \
        "${desktopFile}"
    sed -i "s:Icon=${pkgName}:Icon=${HOME}/.local/share/icons/hicolor/256x256/${pkgName}.png:" \
        "${desktopFile}"
    sed -i "s:Path=/usr/bin:path=${installationDir}:" \
        "${desktopFile}"

    # Copy over new .desktop files
    mkdir -p "${HOME}/.local/share/applications"
    cp -f "${installationDir}/${pkgName}.desktop" "${HOME}/.local/share/applications/${pkgName}.desktop"
}

if [[ $# -gt 0 ]]; then
    for branch in "$@"; do
        if ! isValidBranch "${branch}"; then
            echo "The branch \"${branch}\" does not exist"
            continue
        fi
        installBranch "${branch}" &
    done
    wait
else
    installBranch stable
fi