#!/usr/bin/env bash

set -euo pipefail

SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
# shellcheck source=wp13-common.sh
source "${SCRIPT_DIR}/wp13-common.sh"

usage() {
  cat <<'EOF'
Usage: restore.sh --backup-dir PATH --project-name NAME --confirm-project NAME [options]

Restore a WP13 backup into a new, empty Compose project. Same-project restore
is intentionally blocked; use a new disaster-recovery project and cut over
only after validation.

Options:
  --backup-dir PATH       Verified WP13 backup directory.
  --compose-file PATH     Compose file.
  --env-file PATH         Optional isolated port/environment file.
  --project-name NAME     New destination project.
  --confirm-project NAME  Must exactly match --project-name.
  --start                 Start the restored project after volume extraction.
  --timeout SECONDS       Health timeout (default: 600).
  --help                  Show this help.
EOF
}

ROOT="$(wp13_default_root)"
BACKUP_DIR=""
COMPOSE_FILE=""
ENV_FILE=""
PROJECT_NAME=""
CONFIRM_PROJECT=""
START_PROJECT=0
TIMEOUT_SECONDS=600

while [[ $# -gt 0 ]]; do
  case "$1" in
    --backup-dir) BACKUP_DIR="$2"; shift 2 ;;
    --compose-file) COMPOSE_FILE="$2"; shift 2 ;;
    --env-file) ENV_FILE="$2"; shift 2 ;;
    --project-name) PROJECT_NAME="$2"; shift 2 ;;
    --confirm-project) CONFIRM_PROJECT="$2"; shift 2 ;;
    --start) START_PROJECT=1; shift ;;
    --timeout) TIMEOUT_SECONDS="$2"; shift 2 ;;
    --help|-h) usage; exit 0 ;;
    *) wp13_die "unknown argument: $1" ;;
  esac
done

[[ -n "${PROJECT_NAME}" ]] || wp13_die "--project-name is required"
[[ -n "${CONFIRM_PROJECT}" && "${CONFIRM_PROJECT}" == "${PROJECT_NAME}" ]] \
  || wp13_die "project confirmation does not exactly match --project-name"
[[ -n "${BACKUP_DIR}" && -d "${BACKUP_DIR}" ]] \
  || wp13_die "backup directory not found: ${BACKUP_DIR:-<empty>}"
BACKUP_DIR="$(cd "${BACKUP_DIR}" && pwd)"
COMPOSE_FILE="${COMPOSE_FILE:-${ROOT}/deploy/docker/docker-compose.yml}"
[[ -f "${COMPOSE_FILE}" ]] || wp13_die "compose file not found: ${COMPOSE_FILE}"

wp13_verify_checksums "${BACKUP_DIR}"
MANIFEST="${BACKUP_DIR}/backup-manifest.txt"
[[ -f "${MANIFEST}" ]] || wp13_die "backup manifest not found"
SOURCE_PROJECT="$(awk -F= '$1=="source_project" {print $2; exit}' "${MANIFEST}")"
[[ -n "${SOURCE_PROJECT}" ]] || wp13_die "backup source project is missing"
[[ "${PROJECT_NAME}" != "${SOURCE_PROJECT}" ]] \
  || wp13_die "same-project restore is blocked: ${PROJECT_NAME}"

wp13_require_command docker
wp13_assert_no_project_containers "${PROJECT_NAME}"
if docker volume ls \
  --filter "label=com.docker.compose.project=${PROJECT_NAME}" \
  --format '{{.Name}}' | grep -q .; then
  wp13_die "destination project already has labelled volumes: ${PROJECT_NAME}"
fi

while IFS= read -r line; do
  logical_name="$(printf '%s' "${line}" | awk -F'[=|]' '{print $2}')"
  archive_relative="$(printf '%s' "${line}" | awk -F'[=|]' '{print $4}')"
  [[ -n "${logical_name}" && -n "${archive_relative}" ]] \
    || wp13_die "invalid volume manifest entry: ${line}"
  archive_path="${BACKUP_DIR}/${archive_relative}"
  [[ -f "${archive_path}" ]] || wp13_die "volume archive not found: ${archive_relative}"
  destination_name="${PROJECT_NAME}_${logical_name}"
  wp13_log "restoring volume ${logical_name} as ${destination_name}"
  docker volume create \
    --label "com.docker.compose.project=${PROJECT_NAME}" \
    --label "com.docker.compose.volume=${logical_name}" \
    "${destination_name}" >/dev/null
  docker run --rm \
    -v "${destination_name}:/volume" \
    -v "${BACKUP_DIR}:/backup:ro" \
    postgres:16-alpine \
    sh -c "cd /volume && tar -xzf '/backup/${archive_relative}'"
done < <(grep '^volume=' "${MANIFEST}")

wp13_log "volume restore completed for ${PROJECT_NAME}"

if [[ "${START_PROJECT}" -eq 1 ]]; then
  wp13_compose "${COMPOSE_FILE}" "${PROJECT_NAME}" "${ENV_FILE}" \
    up -d --no-build
  wp13_wait_for_project "${PROJECT_NAME}" "${TIMEOUT_SECONDS}"
  current="$(
    wp13_compose "${COMPOSE_FILE}" "${PROJECT_NAME}" "${ENV_FILE}" \
      exec -T backend alembic -c alembic.ini current \
      | awk 'NF {print $1; exit}'
  )"
  head="$(
    wp13_compose "${COMPOSE_FILE}" "${PROJECT_NAME}" "${ENV_FILE}" \
      exec -T backend alembic -c alembic.ini heads \
      | awk 'NF {print $1; exit}'
  )"
  [[ -n "${current}" && "${current}" == "${head}" ]] \
    || wp13_die "restored database migration mismatch: current=${current:-unknown}, head=${head:-unknown}"
  wp13_log "restored project is healthy at migration ${current}"
fi