#!/usr/bin/env bash
# Updates an existing wireguard-ui-multi installation: pulls the latest
# source, rebuilds frontend assets + binary if needed, reinstalls, and
# restarts the service.
#
# Usage (as root):
#   cd /opt/wireguard-ui-multi-src && ./update.sh
# or from anywhere:
#   /opt/wireguard-ui-multi-src/update.sh --src-dir /opt/wireguard-ui-multi-src
set -euo pipefail

SRC_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
REF="main"
RESTART=1

while [[ $# -gt 0 ]]; do
	case "$1" in
		--src-dir) SRC_DIR="$2"; shift 2 ;;
		--ref) REF="$2"; shift 2 ;;
		--no-restart) RESTART=0; shift ;;
		-h|--help)
			echo "Usage: $0 [--src-dir <path>] [--ref <branch>] [--no-restart]" >&2
			exit 1
			;;
		*) echo "Unknown option: $1" >&2; exit 1 ;;
	esac
done

if [[ "$(id -u)" -ne 0 ]]; then
	echo "Must run as root (rebuilds and reinstalls the service)." >&2
	exit 1
fi

export PATH="/usr/local/go/bin:/usr/local/bin:$PATH"

if [[ ! -d "$SRC_DIR/.git" ]]; then
	echo "No git checkout found at $SRC_DIR. Run bootstrap.sh first." >&2
	exit 1
fi

echo "Fetching latest $REF..."
git -C "$SRC_DIR" fetch --depth 1 origin "$REF"
BEFORE="$(git -C "$SRC_DIR" rev-parse HEAD)"
PREV_PACKAGE_JSON_HASH="$(sha256sum "$SRC_DIR/package.json" 2>/dev/null | awk '{print $1}')"
git -C "$SRC_DIR" checkout "$REF"
git -C "$SRC_DIR" reset --hard "origin/$REF"
AFTER="$(git -C "$SRC_DIR" rev-parse HEAD)"
NEW_PACKAGE_JSON_HASH="$(sha256sum "$SRC_DIR/package.json" 2>/dev/null | awk '{print $1}')"

if [[ "$BEFORE" == "$AFTER" ]]; then
	echo "Already up to date ($AFTER)."
else
	echo "Updated $BEFORE -> $AFTER"
fi

cd "$SRC_DIR"

if [[ "$PREV_PACKAGE_JSON_HASH" != "$NEW_PACKAGE_JSON_HASH" ]] || [[ ! -d assets/dist ]]; then
	echo "Frontend dependencies changed (or assets missing), rebuilding assets..."
	if ! command -v yarn >/dev/null 2>&1; then
		echo "yarn not found; install nodejs/npm/yarn first (see bootstrap.sh)." >&2
		exit 1
	fi
	bash prepare_assets.sh
fi

echo "Rebuilding binary..."
go mod tidy
CGO_ENABLED=0 go build -trimpath -ldflags="-s -w" -o wireguard-ui .

echo "Reinstalling..."
bash scripts/install.sh

if [[ "$RESTART" -eq 1 ]]; then
	if systemctl is-enabled --quiet wireguard-ui-multi.service 2>/dev/null || systemctl is-active --quiet wireguard-ui-multi.service 2>/dev/null; then
		echo "Restarting wireguard-ui-multi.service to pick up the new binary..."
		systemctl restart wireguard-ui-multi.service
		systemctl status --no-pager wireguard-ui-multi.service
	else
		echo "Service not enabled/active yet, skipping restart. Start it with:"
		echo "  systemctl enable --now wireguard-ui-multi.service"
	fi
else
	echo "Skipping restart (--no-restart). Restart manually with:"
	echo "  systemctl restart wireguard-ui-multi.service"
fi

echo
echo "Update complete."