#!/bin/bash

# Name: remove_versions
# Author: pinagamer
# Date: 2019-04-09
# Version: 1.0

DEFAULT_TIMESTAMP="2 month"
DATE_FORMAT="+%FT%T"
TEST_ARG=0
NUM_VERSIONS=0

check_service_name(){
	SERVICES_NAME=($(gcloud app services list | tail -n +2 | awk '{ print $1 }'))
	for serv in "${SERVICES_NAME[@]}"
	do
		:
		if [[ "$SERVICE_ARG" == "$serv" ]]; then
			return 1
		fi
	done
	return 0
}

show_help_menu(){
	echo "Help command"
	echo "    -h : Show this menu"
	echo "    -t : Test mode. It will not perform any risky operation"
	echo "    -d : Date filter. Specify the interval to filter the versions"
	echo "    -s : Service filter"
}

# Check arguments
while getopts ":htd:s:" opt; do
	case $opt in
		h)
			show_help_menu
			exit
			;;
		t)
			echo "testing option (-t) detected"
			TEST_ARG=1
			;;
		d)
			echo "date option (-d) detected. Parameter: $OPTARG" >&2
			DATE_ARG=$OPTARG
			;;
		s)
			echo "service option (-s) detected. Parameter: $OPTARG" >&2
			SERVICE_ARG=$OPTARG
			check_service_name
			if [[ $? != 1 ]]; then
				echo "ERROR! Invalid service with the name '$SERVICE_ARG'"
				echo "Possible values: [ ${SERVICES_NAME[@]} ]"
				exit
			fi
			;;
		\?)
			echo "Invalid option: -$OPTARG" >&2
			;;
		:)
			echo "Option -$OPTARG requires an argument" >&2
			exit 1
			;;
	esac
done

DATE_LIMIT=$(date $DATE_FORMAT -d "-${DATE_ARG:-$DEFAULT_TIMESTAMP}")
echo $DATE_LIMIT

# Apply logic
if [[ $TEST_ARG == 0 ]]; then
	echo "WARNING! This is not test mode"
	if [[ $SERVICE_ARG == "" ]]; then
		echo "WARNING! Versions will be deleted from all versions"
		gcloud app versions list | tail -n +2 | awk -v DATE_LIMIT=$DATE_LIMIT '{
	        SERVICE_FIELD=$1;
	        VERSION_FIELD=$2;
	        LAST_DEPLOYED_FIELD=$4;

            if(DATE_LIMIT > LAST_DEPLOYED_FIELD){
                printf("Removing version %s from service %s\n", VERSION_FIELD, SERVICE_FIELD);
                system("gcloud app versions delete --quiet --service " SERVICE_FIELD " " VERSION_FIELD);
            }
		}'
	else
		echo "Service identified"
		echo "Versions will be deleted only from '$SERVICE_ARG' service"
		gcloud app versions list | tail -n +2 | awk -v DATE_LIMIT=$DATE_LIMIT -v SERVICE_ARG=$SERVICE_ARG '{
	        SERVICE_FIELD=$1;
	        VERSION_FIELD=$2;
	        LAST_DEPLOYED_FIELD=$4;

            if(DATE_LIMIT > LAST_DEPLOYED_FIELD && SERVICE_ARG == SERVICE_FIELD){
                printf("Removing version %s from service %s\n", VERSION_FIELD, SERVICE_FIELD);
                system("gcloud app versions delete --quiet --service " SERVICE_FIELD " " VERSION_FIELD);
            }
		}'

	fi
else
	echo "This is the test mode. It WILL NOT DELETE any version"
	if [[ $SERVICE_ARG == "" ]]; then
		gcloud app versions list | tail -n +2 | awk -v DATE_LIMIT=$DATE_LIMIT '{
	        SERVICE_FIELD=$1;
	        VERSION_FIELD=$2;
	        LAST_DEPLOYED_FIELD=$4;

            if(DATE_LIMIT > LAST_DEPLOYED_FIELD){
                printf("Version %s from service %s would be removed\n", VERSION_FIELD, SERVICE_FIELD);
            }
		}'
	else
		echo "Service identified"
		gcloud app versions list | tail -n +2 | awk -v DATE_LIMIT=$DATE_LIMIT -v SERVICE_ARG=$SERVICE_ARG '{
	        SERVICE_FIELD=$1;
	        VERSION_FIELD=$2;
	        LAST_DEPLOYED_FIELD=$4;

            if(DATE_LIMIT > LAST_DEPLOYED_FIELD && SERVICE_ARG == SERVICE_FIELD){
                printf("Version %s from service %s would be removed\n", VERSION_FIELD, SERVICE_FIELD);
            }
		}'
	fi
fi