#!/usr/bin/env bash

set -e

# In case plans directory is not there
PLAN_FOLDER=".plans"
[[ -d $PLAN_FOLDER ]] || mkdir -p "${PLAN_FOLDER}"

# Prepare plan variables
if type -t gdate >/dev/null ; then
	# GNU date on MacOS is gdate
	PLAN_NAME="$( gdate --iso-8601=minutes )-plan"
else
	# Fall back to Linux date
	PLAN_NAME="$( date --iso-8601=minutes )-plan"
fi
PLAN_FILE="${PLAN_FOLDER}/${PLAN_NAME}"

# Compress old plans
find "${PLAN_FOLDER}" -type f ! -name "*.gz" -execdir gzip -f "{}" \; || exit

# Pick tfvars file
readarray -t FILELIST <<<$( find . -type f -name "*.tfvars" )
TFVAR_COUNT=${#FILELIST[@]}
if (( TFVAR_COUNT <= 0 )); then
	printf "No tfvars file found.\n"
	exit 1
fi
printf "${TFVAR_COUNT} tfvar files found. Pick the number.\n"
FILELIST_OUTPUT=$(find . -type f -name "*.tfvars")
printf "${FILELIST_OUTPUT}\n" | nl
read -rp "Pick file number (1): " TFVAR_PICK
if (( TFVAR_PICK > 0 )) && (( TFVAR_PICK <= TFVAR_COUNT )); then 
	TFVAR_PICK_FILE=${FILELIST[$(( TFVAR_PICK++ ))]}
else
	printf "Pick is invalid.\n"
	exit 1
fi

# Autoformat before execution
terraform fmt && 
	find . -type f \( -name "*.tf"  -o -name "*.tfvars" \) -exec terraform fmt "{}" \; || exit

# Validate configuration
terraform validate . || exit 1

# Upgrade first to handle module changes
terraform init -upgrade || exit 1

# Start Terraform plan with selected var file
terraform plan -out "${PLAN_FILE}" -var-file="${TFVAR_PICK_FILE}"
if ! (( $? == 0 )); then
	printf "Terraform plan failed. Please check your Terraform files.\n"
	exit 1
fi

apply_plan_file_auto_approve () {
	terraform apply -auto-approve "${PLAN_FILE}"
	mv "${PLAN_FILE}" "${PLAN_FILE}-applied"
}

apply_plan_file_approve () {
	terraform apply "${PLAN_FILE}"
	mv "${PLAN_FILE}" "${PLAN_FILE}-applied"
}

if [[ $1 == '-y' ]]; then
	apply_plan_file_auto_approve
	exit
fi
read -rp "Apply?\n terraform apply \"${PLAN_FILE}\" (y/n): " ANSWER
if [[ $ANSWER == 'y' ]]; then
	apply_plan_file_approve
        exit
fi