publisher

#!/usr/bin/env bash
WAIT=2

function scriptUsage() {
	cat << EOF
Publish from remote storage and observe file changes

Usage: ./publisher [-h|-n|-s DIR]

Options:
	 -h|--help                  Displays this help
	 -n|--no-npm-install        Publish without npm install
	 -s|--source-dir [DIR]      Source directory name
	 -w|--wait [NUMBER]      	Waiting time in seconds (default: 2 seconds)
EOF
}

startTimer() {
	start=$(date +%s.%N)
}
	
endTimer() {
	duration=$( echo "$(date +%s.%N)-$start" | bc | cut -b1-5 )
}

fetchFiles() {
	startTimer
	files=$(find . -type f \( -name "*.*" ! -path "\./\.*" ! -path "\./publisher" \) \
		| git check-ignore --verbose --non-matching --stdin \
		| sed -n -e 's,\t./,\t,' -e 's,^::\t*,,p')
	if [ -z "$files" ]; then
		echo "No files found in the given directory"
		exit 1
	fi
	endTimer
	echo "Directory scanned in $duration seconds"
}

function parseParams() {
	local param
	while [[ $# -gt 0 ]]; do
		param="$1"
		shift
		case $param in
			-h | --help)
				scriptUsage
				exit 0
				;;
			-n | --no-npm-install)
				noNpmInstall=true
				;;
			-s | --source-dir)
				srcDir=$1
				if [ -z "$srcDir" ]; then
					echo "Expecting a directory name after -s option."
					exit 1
				else
					if [ -d "$srcDir" ]; then
						cd $srcDir
					else
						echo "The given directory does not exists."
						exit 1
					fi
				fi
				shift
				;;
			-w | --wait)
				WAIT=$1
				if ! [[ $WAIT =~ '^[0-9]+$' ]]; then
				   echo "Error: Wait given is not a number" >&2; exit 1
				fi
				;;
			*)
			echo "Invalid parameter was provided: $param."
			exit 1
			;;
		esac
	done
}

function publish() {
	startTimer
	echo
	echo "[$(date)]: Publishing worker"
	wrangler publish
	currentHash=$newHash
	endTimer
}

function checkHash() {
	newHash=$(sha1sum $files | sha1sum | awk '{print $1}')
	if [[ "$newHash" != "$currentHash" ]]; then
		publish
		echo "Published worker in $duration seconds."
		printf "Scanning for file change..."
	fi
}

function initScript() {
	if [[ -z ${noNpmInstall-} ]]; then
		npm install --no-bin-links
	fi
	while true; do
		checkHash
		sleep $WAIT
	done
}

function main() {
	fetchFiles
	parseParams "$@"
	initScript
}

main "$@"