/**
 * The `notifications` table: its row type, its guard, and its mapper to the
 * API's {@link Notification}.
 *
 * @module
 */

import type { SQLOutputValue } from "node:sqlite";
import type {
  Notification,
  NotificationData,
  NotificationType,
} from "../../shared/notification.ts";

/** A row of the `notifications` table. */
export interface NotificationRow {
  /** The notification's id. */
  id: string;
  /** The id of the user notified. */
  user_id: string;
  /** The notification's {@link NotificationType}. */
  type: string;
  /** The notification's {@link NotificationData}, as JSON. */
  data: string;
  /** 1 once the user has read it. */
  read: number;
  /** When the notification was made. */
  created_at: string;
  /**
   * What caused the notification: a second one with the same
   * `(user_id, source_key)` isn't stored. Null when duplicates are allowed.
   */
  source_key: string | null;
  /** Any other column the query selects. */
  [key: string]: SQLOutputValue;
}

/** Checks whether `obj` is a {@link NotificationRow}. */
export function isNotificationRow(
  obj: unknown,
): obj is NotificationRow {
  return !!obj && typeof obj === "object" &&
    "id" in obj && typeof obj.id === "string" &&
    "user_id" in obj && typeof obj.user_id === "string" &&
    "type" in obj && typeof obj.type === "string" &&
    "data" in obj && typeof obj.data === "string" &&
    "read" in obj && typeof obj.read === "number" &&
    "created_at" in obj && typeof obj.created_at === "string" &&
    "source_key" in obj &&
    (typeof obj.source_key === "string" || obj.source_key === null);
}

/** Converts a row to the API's {@link Notification}. */
export function notificationRowToApi(row: NotificationRow): Notification {
  return {
    id: row.id,
    userId: row.user_id,
    type: row.type as NotificationType,
    data: JSON.parse(row.data) as NotificationData,
    read: Boolean(row.read),
    createdAt: new Date(row.created_at),
  };
}