/**
 * @copyright NHCarrigan
 * @license Naomi's Public License
 * @author Naomi Carrigan
 */

/**
 * Fetches a paginated resource from a URL. Automatically handles pagination,
 * and returns the complete data as an array.
 * @type {Array<Record<string, unknown>>} - The type of data returned from the API endpoint. This should be an array of objects.
 * @param url - The URL to fetch.
 * @param limit - The number of items to fetch per page.
 * @param options - The standard fetch options object.
 * @returns The complete data as type T.
 */
// eslint-disable-next-line max-lines-per-function, max-statements -- We're doing some complex logic here.
export const paginatedFetch = async <T extends Array<Record<string, unknown>>>(
  url: string,
  limit: number,
  options: RequestInit = {},
): Promise<T> => {
  let page = 1;
  let offset = 0;
  // eslint-disable-next-line @typescript-eslint/consistent-type-assertions -- This is a workaround to avoid type errors.
  const data: T = [] as unknown as T;

  // First page
  const firstUrl = `${url}?limit=${limit.toString()}&page=${page.toString()}&offset=${offset.toString()}`;
  console.log(`Fetching page ${page.toString()} (offset ${offset.toString()}, limit ${limit.toString()})...`);
  let request = await fetch(firstUrl, options);

  if (!request.ok) {
    throw new Error(`Failed to fetch ${firstUrl}: ${request.status.toString()} ${request.statusText}`);
  }

  let response: T = await request.json();

  // Check if response is actually an array
  if (!Array.isArray(response)) {
    console.error(
      "API response is not an array:",
      typeof response,
      Object.keys(response),
    );
    const errorMessage
      = `Expected array response but got ${typeof response}. `
      + `Response keys: ${Object.keys(response).join(", ")}`;
    throw new Error(errorMessage);
  }

  console.log(`Page ${page.toString()}: Received ${response.length.toString()} items`);
  data.push(...response);

  /**
   * Continue paginating while we get items back.
   * Keep fetching until we get an empty array (0 items), which means we've reached the end.
   */
  while (response.length > 0) {
    page = page + 1;
    offset = offset + limit;
    const pageUrl = `${url}?limit=${limit.toString()}&page=${page.toString()}&offset=${offset.toString()}`;
    console.log(`Fetching page ${page.toString()} (offset ${offset.toString()}, limit ${limit.toString()})...`);
    request = await fetch(pageUrl, options);

    if (!request.ok) {
      console.error(`Failed to fetch page ${page.toString()}: ${request.status.toString()} ${request.statusText}`);
      break;
    }

    response = await request.json();

    if (!Array.isArray(response)) {
      console.error(`Page ${page.toString()} response is not an array:`, typeof response);
      break;
    }

    console.log(`Page ${page.toString()}: Received ${response.length.toString()} items`);

    // If we get an empty array, we've reached the end
    if (response.length === 0) {
      break;
    }

    data.push(...response);
  }

  console.log(`Total items fetched: ${data.length.toString()}`);
  return data;
};