#!/bin/bash
set -euo pipefail

timestamp()
{
	/usr/bin/date -Ins -u
}

say()
{
	echo -e "$(timestamp): ${@}"
}

warn()
{
	say "⚠️ ${@}"
}

ok()
{
	say "✅ ${@}"
}

doing()
{
	say "👉 ${@}"
}

fail() {
	say "❌ ${@}" 1>&2
	exit ${EXIT_CODE:-1}
}

is_valid_k8s_name()
{
	local NAME="${1}"
	[[ "${NAME}" =~ ^[a-z0-9]([a-z0-9\-]*[a-z0-9])?$ ]] || return ${?}
	return 0
}

usage()
{
	echo -e "usage: ${BASH_ARGV0:-${BASH_SOURCE:-${0}}} release [param1 param2 param3 ... paramN]"
	echo -e ""
	echo -e "\t* release is the name of the Helm release to be deployed (using helm upgrade --install)"
	echo -e ""
	echo -e "\t* each paramX element will be processed as follows:"
	echo -e ""
	echo -e "\t\t* if it's the word '--debug', debug mode will be enabled and the Helm command will not be executed"
	echo -e "\t\t* if it's a file, it will be added as a values file using -f"
	echo -e "\t\t* if it's a folder, its files will be found recursively (using find), as long as"
	echo -e "\t\t  they match the pattern '*.yaml', and they will each be added as values files"
	echo -e "\t\t  using -f, but in strict alphabetical order based on the find output"
	echo -e "\t\t* if it's the string '--', then no further special processing will be applied to the remaining"
	echo -e "\t\t  parameters, and they will be passed on to Helm verbatim (i.e. -- --dry-run)"
	echo -e ""
	echo -e "\tEnvironment varibles may also be used for further customization:"
	echo -e "\t\tNAMESPACE	-> the namespace to deploy into (if not provided, the active namespace for the context will be used)"
	echo -e "\t\tTIMEOUT		-> the timeout (in minutes) to wait for the deployment to complete"
	echo -e "\t\tCHART_NAME	-> the name of the chart to use (the default 'arkcase/app' should suffice)"
	echo -e "\t\tCHART_VERSION	-> the version of the chart to use (use the latest version by default)"

	exit 1
}


[ ${#} -ge 1 ] || usage

type -P helm &>/dev/null || fail "Could not find 'helm' in the path"
type -P kubectl &>/dev/null || fail "Could not find 'kubectl' in the path"

RELEASE="${1}"
is_valid_k8s_name "${RELEASE}" || fail "The release name [${RELEASE}] is not valid"
shift
ok "Release name: ${RELEASE}"

DEBUG="false"
PROCESS="true"
VALUES=()
if [ ${#} -ge 1 ] ; then
	doing "Processing the values: [${@}]"
	for V in "${@}" ; do

		# If processing is turned off, simply append it
		if ! "${PROCESS}" ; then
			VALUES+=("${V}")
			continue
		fi

		# If it's a request to stop processing, flip the
		# flag into the "off" state
		if [ "${V}" == "--" ] ; then
			PROCESS="false"
			continue
		fi

		# Enable debugging?
		if [[ "${V,,}" == "--debug" ]] ; then
			DEBUG="true"
			continue
		fi

		# Set a (single) value?
		if [[ "${V}" =~ ^--set:(.+)$ ]] ; then
			VALUES+=(--set "${BASH_REMATCH[1]}")
			continue
		fi

		# Must be either a file or folder...
		[ -e "${V}" ] || fail "The path [${V}] could not be found"

		if [ -f "${V}" ] ; then
			VALUES+=(-f "${V}")
			continue
		fi

		if [ -d "${V}" ] ; then
			while read V2 ; do
				VALUES+=(-f "${V2}")
			done < <(find "${V}" -type f -iname '*.yaml' | sort)
			continue
		fi

		fail "The path [${V}] is neither a file nor a directory"
	done
	ok "Values processed!"
fi

"${DEBUG}" && warn "DEBUG MODE IS ENABLED"

[ -v CHART_NAME ] || CHART_NAME=""
[ -n "${CHART_NAME}" ] || CHART_NAME="arkcase/app"

[ -v CHART_VERSION ] || CHART_VERSION=""
if [ -n "${CHART_VERSION}" ] ; then
	ok "Set chart version: [${CHART_VERSION}]"
	CHART_VERSION=(--version "${CHART_VERSION}")
else
	CHART_VERSION=()
fi

[ -v NAMESPACE ] || NAMESPACE=""
[ -n "${NAMESPACE}" ] || NAMESPACE="$(kubectl config view --minify -o jsonpath="{..namespace}")"
if [ -n "${NAMESPACE}" ] ; then
	is_valid_k8s_name "${NAMESPACE}" || fail "The namespace [${NAMESPACE}] is not valid"
	NAMESPACE=(--namespace "${NAMESPACE}")
	ok "Set namespace: ${NAMESPACE}"
else
	NAMESPACE=()
fi

[ -v TIMEOUT ] || TIMEOUT=""
if [ -n "${TIMEOUT}" ] ; then
	[[ "${TIMEOUT}" =~ ^[1-9][0-9]*$ ]] || fail "The timeout value [${TIMEOUT}] must be a positive integer"
	ok "Set timeout: [${TIMEOUT} minutes]"
	TIMEOUT=(--wait --timeout "${TIMEOUT}m")
else
	TIMEOUT=()
fi

CMD=(
	helm upgrade --install \
		"${RELEASE}" \
		"${CHART_NAME}" \
		"${CHART_VERSION[@]}" \
		"${NAMESPACE[@]}" \
		"${TIMEOUT[@]}" \
		"${VALUES[@]}"
)

doing "EXECUTING: ${CMD[@]@Q}"
"${DEBUG}" || "${CMD[@]}" || fail "Deployment failed"
ok "Deployment complete!"