#!/usr/bin/env bash
set -euo pipefail

MODE="dry-run"
CUTOFF_DATE="2026-06-02"
ARCHIVE_ROOT="/mnt/user/appdata/_archive/pg18-immich-rollback-volumes-20260602"

if [[ "${1:-}" == "--execute" ]]; then
  MODE="execute"
elif [[ "${1:-}" != "" && "${1:-}" != "--dry-run" ]]; then
  echo "Usage: $0 [--dry-run|--execute]" >&2
  exit 2
fi

if [[ "$(id -u)" -ne 0 ]]; then
  echo "Must run as root on the Unraid host." >&2
  exit 1
fi

today="$(date +%F)"
if [[ "$MODE" == "execute" && "$today" < "$CUTOFF_DATE" ]]; then
  echo "Refusing: cutoff is $CUTOFF_DATE, today is $today." >&2
  exit 1
fi

declare -a CANDIDATES=(
  "/mnt/user/appdata/postgresql17|/mnt/user/appdata/postgresql18|postgresql17|shared PostgreSQL 17 rollback"
  "/mnt/user/appdata/mealie/postgres|/mnt/user/appdata/mealie/postgres18|mealie-postgres17|Mealie PostgreSQL 17 rollback"
  "/mnt/user/appdata/nextcloud/postgres|/mnt/user/appdata/nextcloud/postgres18|nextcloud-postgres17|Nextcloud PostgreSQL 17 rollback"
  "/mnt/user/appdata/immich_postgres|/mnt/user/appdata/immich_postgres_vectorchord|immich-postgres-pgvecto-rs|Immich pgvecto.rs rollback"
)

require_container_healthy() {
  local name="$1"
  local state
  local health

  state="$(docker inspect "$name" --format '{{.State.Status}}' 2>/dev/null || true)"
  health="$(docker inspect "$name" --format '{{if .State.Health}}{{.State.Health.Status}}{{else}}none{{end}}' 2>/dev/null || true)"

  if [[ "$state" != "running" ]]; then
    echo "Container $name is not running (state=$state)." >&2
    exit 1
  fi

  if [[ "$health" != "healthy" && "$health" != "none" ]]; then
    echo "Container $name is not healthy (health=$health)." >&2
    exit 1
  fi
}

echo "Alt-volume archive check"
echo "Mode: $MODE"
echo "Date: $today"
echo "Archive: $ARCHIVE_ROOT"
echo

require_container_healthy postgresql17
require_container_healthy mealie-postgres
require_container_healthy nextcloud-postgres
require_container_healthy immich_postgres

if docker ps --filter health=unhealthy --format '{{.Names}}' | grep -q .; then
  echo "Refusing: unhealthy containers exist." >&2
  docker ps --filter health=unhealthy --format '  {{.Names}} {{.Status}}' >&2
  exit 1
fi

if [[ -x /mnt/user/services/homelab-infra/ops/restore-tests/run-restore-checks.sh ]]; then
  /mnt/user/services/homelab-infra/ops/restore-tests/run-restore-checks.sh freshness
fi

mapfile -t active_mounts < <(docker inspect $(docker ps -aq) --format '{{range .Mounts}}{{println .Source}}{{end}}' 2>/dev/null || true)

if [[ "$MODE" == "execute" ]]; then
  mkdir -p "$ARCHIVE_ROOT"
fi

for entry in "${CANDIDATES[@]}"; do
  IFS='|' read -r old_path active_path archive_name label <<< "$entry"
  archive_path="$ARCHIVE_ROOT/$archive_name"

  if [[ ! -d "$active_path" ]]; then
    echo "Missing active path for $label: $active_path" >&2
    exit 1
  fi

  if printf '%s\n' "${active_mounts[@]}" | grep -Fxq "$old_path"; then
    echo "Refusing: old path is still mounted by a container: $old_path" >&2
    exit 1
  fi

  if [[ -d "$old_path" && -d "$archive_path" ]]; then
    echo "Refusing: both old path and archive path exist for $label." >&2
    echo "Old:     $old_path" >&2
    echo "Archive: $archive_path" >&2
    exit 1
  fi

  if [[ -d "$archive_path" ]]; then
    size="$(du -sh "$archive_path" 2>/dev/null | awk '{print $1}')"
    echo "Archived: $archive_path ($label, $size)"
    echo
    continue
  fi

  if [[ ! -d "$old_path" ]]; then
    echo "Absent and not archived: $old_path ($label)" >&2
    exit 1
  fi

  size="$(du -sh "$old_path" 2>/dev/null | awk '{print $1}')"
  echo "Candidate: $old_path ($label, $size)"
  echo "Active:    $active_path"
  echo "Archive:   $archive_path"

  if [[ "$MODE" == "execute" ]]; then
    mv "$old_path" "$archive_path"
    printf '%s MOVE %s -> %s size=%s\n' "$(date -Is)" "$old_path" "$archive_path" "$size" >> "$ARCHIVE_ROOT/MANIFEST.txt"
    echo "Moved:     $archive_path"
  else
    echo "Dry-run:   would move $old_path to $archive_path"
  fi
  echo
done

echo "Alt-volume archive check completed."