import { courseManifestRepo } from '@/lib/course-manifest-repo/store';
import type { CourseManifestRepo } from '@/lib/course-manifest-repo/types';
import type { CoursewareRecord } from '@/lib/courseware-repo/types';

/**
 * Standalone coursewares become visible when their registry status is
 * published. Large-course-owned versions additionally require an immutable
 * schema-v2 manifest that contains this exact id/version/hash pin.
 */
export async function isCoursewareLearnerVisible(
  record: CoursewareRecord,
  manifests: CourseManifestRepo = courseManifestRepo,
): Promise<boolean> {
  if (record.status !== 'published' || !record.complete) return false;

  const courseId = record.courseId;
  const moduleIndex = record.courseModuleIndex;
  if (courseId === undefined && moduleIndex === undefined) return true;
  if (
    typeof courseId !== 'string' ||
    !/^[a-zA-Z0-9_-]+$/.test(courseId) ||
    !Number.isInteger(moduleIndex) ||
    (moduleIndex ?? 0) < 1
  ) {
    return false;
  }

  try {
    return await manifests.hasExactPin(courseId, {
      index: moduleIndex as number,
      coursewareId: record.coursewareId,
      coursewareVersion: record.version,
      contentHash: record.contentHash,
    });
  } catch {
    // Manifest state is an authorization/visibility boundary. Corrupt or
    // unavailable state must hide the course-scoped bundle.
    return false;
  }
}

export async function filterLearnerVisibleCoursewares(
  records: readonly CoursewareRecord[],
  manifests: CourseManifestRepo = courseManifestRepo,
): Promise<CoursewareRecord[]> {
  const visibility = await Promise.all(
    records.map((record) => isCoursewareLearnerVisible(record, manifests)),
  );
  return records.filter((_record, index) => visibility[index]);
}