#!/usr/bin/env bash

set -Eeuo pipefail

WM_DEPLOY_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
# shellcheck source=common.sh
source "$WM_DEPLOY_DIR/scripts/common.sh"

if [[ "$(id -u)" -ne 0 ]]; then
  wm_die "Dieses Skript muss als root ausgeführt werden."
fi

wm_load_env
revision="${1:-previous}"
deployments_dir="$WATERMAPS_RUNTIME_DIR/deployments"

if [[ "$revision" == "previous" ]]; then
  images_file="$deployments_dir/previous.env"
else
  [[ "$revision" =~ ^[0-9a-f]{40}$ ]] ||
    wm_die "Rollback-Ziel muss 'previous' oder eine vollständige Git-Commit-SHA sein."
  images_file="$deployments_dir/$revision.env"
fi

[[ -f "$images_file" ]] ||
  wm_die "Gespeichertes Release nicht gefunden: $images_file"

target_revision="$(wm_env_value "$images_file" WATERMAPS_DEPLOY_REVISION)"
release_directory="$WATERMAPS_DATA_DIR/releases/$target_revision"
[[ -d "$release_directory" &&
      -x "$release_directory/deploy/scripts/deploy.sh" ]] ||
  wm_die "Unveränderliches Release-Bundle fehlt: $release_directory"

install_root="${WATERMAPS_INSTALL_DIR:-/opt/watermaps}"
wm_require_safe_absolute_dir "$install_root"
active_images_file="${WATERMAPS_ACTIVE_IMAGES_FILE:-$install_root/deploy/.env.images}"

WATERMAPS_ENV_FILE="$WM_ENV_FILE" \
WATERMAPS_ACTIVE_IMAGES_FILE="$active_images_file" \
  "$release_directory/deploy/scripts/deploy.sh" \
    --images-file "$images_file"

temporary_link="$install_root/.current.rollback.$$.new"
trap 'rm -f -- "$temporary_link"' EXIT HUP INT TERM
ln --symbolic "$release_directory" "$temporary_link"
mv --no-target-directory "$temporary_link" "$install_root/current"
temporary_link=""

for unit in \
  watermaps-auto-deploy.service \
  watermaps-auto-deploy.timer \
  watermaps-route-update.service \
  watermaps-route-update.timer \
  watermaps-certbot-renew.service \
  watermaps-certbot-renew.timer; do
  install -m 0644 \
    "$release_directory/deploy/systemd/$unit" \
    "/etc/systemd/system/$unit"
done
systemctl daemon-reload

wm_log "Rollback auf Commit $target_revision ist geprüft und atomar aktiviert."