/**
 * @typedef {{ current: number, total: number, file: File }} BatchProgress
 */

/**
 * Run gallery identify sequentially over multiple files with progress, cancel, and per-file failure continuation.
 *
 * @param {File[] | FileList | Iterable<File>} files
 * @param {(file: File) => Promise<unknown>} identifyFn
 * @param {{
 *   onProgress?: (progress: BatchProgress) => void,
 *   onFileSuccess?: (payload: { file: File, index: number }) => void,
 *   onFileError?: (payload: { file: File, index: number, error: unknown }) => void,
 *   cancelRef?: { current: boolean },
 * }} [options]
 * @returns {Promise<{ results: Array<{ file: File, ok: true } | { file: File, ok: false, error: unknown }>, cancelled: boolean }>}
 */
export async function runSequentialGalleryIdentify(files, identifyFn, options = {}) {
  const {
    onProgress,
    onFileSuccess,
    onFileError,
    cancelRef = { current: false },
  } = options;

  const list = Array.from(files || []);
  const total = list.length;
  const results = [];

  for (let i = 0; i < list.length; i++) {
    if (cancelRef.current) break;
    const file = list[i];
    onProgress?.({ current: i + 1, total, file });

    try {
      await identifyFn(file);
      results.push({ file, ok: true });
      onFileSuccess?.({ file, index: i });
    } catch (error) {
      results.push({ file, ok: false, error });
      onFileError?.({ file, index: i, error });
    }
  }

  return { results, cancelled: cancelRef.current };
}