// Large-course mode API — cancel a course generation run.
//
//   POST /api/courses/:courseId/cancel
//
// Aborts the full pipeline (and any module-regeneration cascade) and cooperatively
// cancels the in-flight classroom job of the current module. Succeeded modules
// are kept; the course status flips to `cancelled` once the run settles.

import { type NextRequest } from 'next/server';
import { apiError, apiSuccess, API_ERROR_CODES } from '@/lib/server/api-response';
import { createLogger } from '@/lib/logger';
import { isValidCourseId, readCourseRecordReconciled } from '@/lib/course-framework/store';
import {
  cancelCourseGenerationJob,
  isCourseGenerationRunning,
} from '@/lib/course-framework/runner';
import { requireOpsAccess } from '@/lib/server/ops-access';
import { proxyLargeCourseControlToEngine } from '@/lib/makelore-runtime/ops-engine-control';

const log = createLogger('Course Cancel API');

export async function POST(
  request: NextRequest,
  { params }: { params: Promise<{ courseId: string }> },
) {
  const denied = await requireOpsAccess(request);
  if (denied) return denied;

  try {
    const { courseId } = await params;
    if (!isValidCourseId(courseId)) {
      return apiError(API_ERROR_CODES.INVALID_REQUEST, 400, `Invalid course id: ${courseId}`);
    }
    const record = await readCourseRecordReconciled(courseId);
    if (!record) {
      return apiError(API_ERROR_CODES.INVALID_REQUEST, 404, `Course not found: ${courseId}`);
    }
    const proxied = await proxyLargeCourseControlToEngine({
      request,
      course: record,
      action: 'cancel',
    });
    if (proxied) return proxied;
    if (!isCourseGenerationRunning(courseId)) {
      return apiError(API_ERROR_CODES.INVALID_REQUEST, 409, 'Course generation is not running');
    }
    cancelCourseGenerationJob(courseId);
    log.info(`Course cancellation requested: ${courseId}`);
    return apiSuccess({ courseId, message: 'Cancellation requested' });
  } catch (error) {
    log.error('Course cancel failed:', error);
    return apiError(API_ERROR_CODES.INTERNAL_ERROR, 500, 'Failed to cancel course');
  }
}