#!/usr/bin/env bash
# Install TA-ProxMenu on a Proxmox VE host.

set -Eeuo pipefail

readonly INSTALL_ROOT='/opt/idssys'
readonly TAPM_DIR="${INSTALL_ROOT}/ta-proxmenu"
readonly DEFAULTS_DIR="${INSTALL_ROOT}/defaults"
readonly TAPM_REPOSITORY='https://git.scity.us/TAI/TA-ProxMenu.git'
readonly DEFAULTS_REPOSITORY='https://git.scity.us/voltron/iDS-Defaults.git'
readonly TAPM_LAUNCHER='/usr/local/bin/tapm'
readonly REQUESTED_BRANCH="${TAPM_BRANCH:-}"

declare -a TEMP_PATHS=()

cleanup() {
	local path

	for path in "${TEMP_PATHS[@]}"; do
		[[ -e "$path" ]] && rm -rf -- "$path"
	done
}

fail() {
	printf 'ERROR: %s\n' "$*" >&2
	exit 1
}

clone_repository() {
	local repository="$1"
	local destination="$2"
	local label="$3"
	local branch="${4:-}"
	local temporary

	if [[ -d "${destination}/.git" ]]; then
		printf '%s is already installed at %s; leaving it unchanged.\n' \
			"$label" "$destination"
		return
	fi

	[[ ! -e "$destination" ]] ||
		fail "${destination} already exists but is not a Git repository."

	temporary="${destination}.install.$$"
	TEMP_PATHS+=("$temporary")

	printf 'Cloning %s...\n' "$label"
	if [[ -n "$branch" ]]; then
		git clone --branch "$branch" --single-branch \
			"$repository" "$temporary"
	else
		git clone "$repository" "$temporary"
	fi

	mv "$temporary" "$destination"
}

install_launcher() {
	local current_target=''

	if [[ -L "$TAPM_LAUNCHER" ]]; then
		current_target="$(readlink "$TAPM_LAUNCHER")"
		if [[ "$current_target" == "${TAPM_DIR}/run.sh" ]]; then
			return
		fi

		fail "${TAPM_LAUNCHER} points to ${current_target}; it was not replaced."
	fi

	[[ ! -e "$TAPM_LAUNCHER" ]] ||
		fail "${TAPM_LAUNCHER} already exists and was not replaced."

	ln -s "${TAPM_DIR}/run.sh" "$TAPM_LAUNCHER"
}

trap cleanup EXIT

(( EUID == 0 )) || fail 'Run this installer as root.'
command -v pveversion >/dev/null 2>&1 ||
	fail 'This installer must be run on a Proxmox VE host.'

if [[ -n "$REQUESTED_BRANCH" ]] &&
	[[ ! "$REQUESTED_BRANCH" =~ ^[A-Za-z0-9._/-]+$ ]]; then
	fail "Invalid TAPM_BRANCH value: ${REQUESTED_BRANCH}"
fi

printf '\nTA-ProxMenu Installation Script\n\n'

apt-get update
DEBIAN_FRONTEND=noninteractive apt-get install -y \
	ca-certificates curl git jq python3 wget

mkdir -p "$INSTALL_ROOT"

clone_repository \
	"$DEFAULTS_REPOSITORY" "$DEFAULTS_DIR" 'iDSSYS Defaults'
clone_repository \
	"$TAPM_REPOSITORY" "$TAPM_DIR" 'TA-ProxMenu' "$REQUESTED_BRANCH"

[[ -x "${TAPM_DIR}/run.sh" ]] ||
	fail "${TAPM_DIR}/run.sh is missing or is not executable."
[[ -r "${DEFAULTS_DIR}/colors.inc" ]] ||
	fail "${DEFAULTS_DIR}/colors.inc is missing."
[[ -r "${DEFAULTS_DIR}/default.inc" ]] ||
	fail "${DEFAULTS_DIR}/default.inc is missing."

install_launcher

# Load the standard colors only after the trusted defaults repository exists.
# shellcheck disable=SC1091
source "${DEFAULTS_DIR}/colors.inc"

printf '\n%bTA-ProxMenu has been installed.%b\n\n' \
	"${idsCL[Yellow]}" "${idsCL[Default]}"
printf 'Run it with: %btapm%b\n\n' \
	"${idsCL[Green]}" "${idsCL[Default]}"

if [[ -n "$REQUESTED_BRANCH" ]]; then
	printf 'Installed branch: %b%s%b\n\n' \
		"${idsCL[Green]}" "$REQUESTED_BRANCH" "${idsCL[Default]}"
fi