urlencode / urldecode as a shell script

urlencode

#!/bin/sh

SCRIPT_NAME="$(basename "$0")"

if [ "$SCRIPT_NAME" != "urlencode" ] && [ "$SCRIPT_NAME" != "urldecode" ]; then
    echo 'Please run this script as "urlencode" or "urldecode"'
    exit 1
fi

if [ $# -lt 1 ]; then
    echo "Usage: $SCRIPT_NAME <url>"
    exit 1
fi

case "$SCRIPT_NAME" in
    urlencode)
        test -x /usr/bin/python3 \
            && exec /usr/bin/python3 -c "import sys; import urllib.parse as up; print(up.quote_plus(sys.argv[1]))" "$1"
        test -x /usr/bin/python2 \
            && exec /usr/bin/python2 -c "import sys; import urllib as ul; print ul.quote_plus(sys.argv[1])" "$1"
        test -x /usr/bin/ruby \
            && exec /usr/bin/ruby -r cgi -e "puts CGI.escape(ARGV[0])" "$1"
        test -x /usr/bin/php \
            && exec /usr/bin/php -r 'echo rawurlencode($argv[1]), "\n";' "$1"
        test -x /usr/bin/perl && /usr/bin/perl -MURI::Escape -e 1 >/dev/null 2>&1 \
            && exec /usr/bin/perl -MURI::Escape -e 'print uri_escape($ARGV[0]), "\n";' -- "$1";
        test -x /usr/bin/node \
            && exec /usr/bin/node -e "console.log(encodeURIComponent(process.argv[1]))" "$1"
        ;;

    urldecode)
        test -x /usr/bin/python3 \
            && exec /usr/bin/python3 -c "import sys; import urllib.parse as up; print(up.unquote_plus(sys.argv[1]))" "$1"
        test -x /usr/bin/python2 \
            && exec /usr/bin/python2 -c "import sys; import urllib as ul; print ul.unquote_plus(sys.argv[1])" "$1"
        test -x /usr/bin/ruby \
            && exec /usr/bin/ruby -r cgi -e "puts CGI.unescape(ARGV[0])" "$1"
        test -x /usr/bin/php \
            && exec /usr/bin/php -r 'echo rawurldecode($argv[1]), "\n";' "$1"
        test -x /usr/bin/perl && /usr/bin/perl -MURI::Escape -e 1 >/dev/null 2>&1 \
            && exec /usr/bin/perl -MURI::Escape -e 'print uri_unescape($ARGV[0]), "\n";' -- "$1";
        test -x /usr/bin/node \
            && exec /usr/bin/node -e "console.log(decodeURIComponent(process.argv[1]))" "$1"
        ;;
esac