function jaaENV {
	if [ "$1" = "--help" ]; then
		echo "Utility to combine nvm/sdk/… in one script/config file '.jaaENV'"
		echo "	 ↘ instead of 'nvm use 16 & sdk use …'"
		echo ""
		echo "Usage:"
		echo "	jaaENV"
		echo "	jaaENV [--help|--ls]"
		echo "	jaaENV --save …to_save (example: jaaENV --save nodejs php)"
		echo ""
		echo "Description:"
		echo "	- Without arguments, loads info from '.jaaENV'"
		echo "	- 'ls' shows supported options to auto-load"
		echo "	- 'save' creates a config file '.jaaENV'"
		echo ""
		echo "Usage '.jaaENV' files: "
		echo "	  typical: '\nphp=5.6\nnodejs=16.13.0'"
		echo "		 link: '. ../.jaaENV' … use settings from parent folder"
		echo "	Options:"
		echo "		'android_home': Exports 'ANDROID_HOME' (uses 'ANDROID_HOME_BAK') instead of 'ANDROID_SDK_ROOT'. Value can be anything (use '1')."
		echo "		         'jdk': Exports 'JAVA_HOME' based on the wanted version (currently 11/1.8)"
		echo "		'nodejs'|'php': NodeJS/PHP versions"
		echo "		      'gradle': Cordova uses folder-scoped → so unnecesarly"
		echo ""
		echo "Install: "
		echo "	  gradle ⇒ https://sdkman.io/"
		echo "		node ⇒ https://github.com/nvm-sh/nvm"
		echo "		 php ⇒ \`update-alternatives\` + https://deb.sury.org/"
		echo "		java ⇒ \`update-alternatives\`"
		echo ""
		echo "Tips:"
		echo "	sudo update-alternatives --set php /usr/bin/php\$php"
		return 0
	fi

	if [ "$1" == "--save" ]; then
		shift
		rm -vi .jaaENV
		while [ $# -gt 0 ]; do
			case "$1" in
				nodejs|node)
					echo "nodejs=$(node --version | cut -c2-)" >> .jaaENV
					;;
				gradle)
					echo "gradle=$(gradle --version | awk '/Gradle/ {print $2}')" >> .jaaENV
					;;
				php)
					echo "php=$(php --version | awk '/^PHP/ {print $2}')" >> .jaaENV
					;;
				java)
					local java_version=$(java -version 2>&1 | awk -F '"' '/version/ {print $2}')
					if [[ "$java_version" == 1.8* ]]; then
						java_version=8
					else
						java_version=$(echo "$java_version" | cut -d'.' -f1)
					fi
					echo "java=$java_version" >> .jaaENV
					;;
				*)
					echo "Unknown '$1' – skipped"
					;;
			esac
			shift
		done
		return 0
	fi

	if [ "$1" == "--ls" ]; then
		echo ":: nvm ls --no-alias ::"
		nvm ls --no-alias
		echo ":: update-alternatives --list php ::"
		update-alternatives --list php
		echo ":: update-alternatives --list java ::"
		update-alternatives --list java
		echo ":: sdk ls gradle | grep -E '\*|>' :: "
		sdk ls gradle | grep -E '\*|>'
		return 0
	fi
	
	if [ -f "compose.yaml" ]; then
		jdk=$(grep -Po 'VERSION_JAVA=\K.*' compose.yaml)
		nodejs=$(grep -Po 'VERSION_NODEJS=\K.*' compose.yaml)
	elif [ -f ".jaaENV" ]; then
		. ./.jaaENV
	else
		echo 'No env file `compose.yaml` or `.jaaENV`'
		return 1
	fi
	
	local chP="\[\033[0;35m\]"	  #purple
	local chW="\[\033[00m\]"	  #white
	export PS1_jaaENV="${chP}⋮${chW}"
	
	if [ ! -z ${ANDROID_SDK_ROOT_BAK+x} ]; then
		export ANDROID_SDK_ROOT=$ANDROID_SDK_ROOT_BAK
		echo \$ANDROID_SDK_ROOT=$ANDROID_SDK_ROOT_BAK
		unset ANDROID_SDK_ROOT_BAK
	fi
	if [ ! -z ${unset_android_sdk+x} ]; then
		export ANDROID_SDK_ROOT_BAK=$ANDROID_SDK_ROOT
		unset ANDROID_SDK_ROOT
	fi
	if [ ! -z ${java+x} ]; then
		[[ "$java" == "8" ]] && java=1.8
		local java_local=$(java -version 2>&1 | awk -F '"' '/version/ {print $2}')
		if [[ "$java_local" != "$java"* ]]; then
			[[ "$java" == "1.8" ]] && java=8
			echo "Switching Java version: $java ← $java_local"
			local java_path="/usr/lib/jvm/java-$java-openjdk-amd64/"
			[[ "$java" == "8" ]] && java_path+="jre/"
			sudo update-alternatives --set java "${java_path}bin/java"
			local javac=$(update-alternatives --list javac | grep java-$java)
			[ -n "$javac" ] && sudo update-alternatives --set javac "$javac"
			sudo -k
		fi
		export JAVA_HOME=$(readlink -f $(which java) | cut -d '/' -f1-5)/
		echo "\$JAVA_HOME=$JAVA_HOME"
	fi
	if [ ! -z ${android_home+x} ]; then
		export ANDROID_HOME=$ANDROID_HOME_BAK
		echo "\$ANDROID_HOME=$ANDROID_HOME"
	else
		unset ANDROID_HOME
		echo "\$ANDROID_SDK_ROOT=$ANDROID_SDK_ROOT"
	fi
	if [ ! -z ${android_home_is_sdk+x} ]; then
		export ANDROID_HOME=$ANDROID_SDK_ROOT
		echo "\$ANDROID_HOME=$ANDROID_HOME"
	fi
	if [ ! -z ${JAVA_HOME_BAK+x} ]; then export JAVA_HOME=$JAVA_HOME_BAK; unset JAVA_HOME_BAK; fi
	if [ ! -z ${jdk+x} ]; then
		if (( $(echo "$jdk > 9" | bc -l) )); then
			export JAVA_HOME_BAK=$JAVA_HOME
			export JAVA_HOME="/snap/android-studio/current/android-studio/jre"
		fi
		echo "\$JAVA_HOME=$JAVA_HOME"
	fi
	if [ ! -z ${nodejs+x} ]; then nvm use $nodejs; fi
	if [ ! -z ${gradle+x} ]; then sdk use gradle $gradle | tr -d '\n'; echo ; fi
	if [ ! -z ${php+x} ];	 then
		local php_local=$(php --version | awk '/^PHP/ {print $2}')
		if [[ "$php_local" == "$php"* ]]; then
			echo "PHP version: $php"
		else
			echo "Switching PHP version: $php ← $php_local"
			sudo update-alternatives --set php "/usr/bin/php$php"
			sudo -k
		fi
	fi
	
	# Cleanup variables
	unset android_home unset_android_sdk nodejs gradle php java
}