import { randomUUID } from 'node:crypto';
import { sendOpenApiProblem, type OpenApiProblemResponse } from './open-api.protocol';

/** Mounted after parsers, before routes; never expose parser errors containing raw input. */
export function openApiBodyErrorMiddleware(
  error: unknown,
  request: { openApiRequestId?: string },
  response: OpenApiProblemResponse,
  next: (error: unknown) => void,
) {
  const type = error && typeof error === 'object' && 'type' in error ? error.type : undefined;
  const failures: Record<string, { status: number; code: string; message: string }> = {
    'entity.parse.failed': { status: 400, code: 'PARAMETER_INVALID', message: '请求体必须为有效的JSON对象' },
    'entity.too.large': { status: 413, code: 'PAYLOAD_TOO_LARGE', message: '请求体超过大小限制' },
    'charset.unsupported': { status: 415, code: 'UNSUPPORTED_MEDIA_TYPE', message: '请求体字符集不受支持' },
    'encoding.unsupported': { status: 415, code: 'UNSUPPORTED_MEDIA_TYPE', message: '请求体编码不受支持' },
  };
  const failure = typeof type === 'string' && Object.hasOwn(failures, type) ? failures[type] : undefined;
  if (!failure) return next(error);
  sendOpenApiProblem(response, (request.openApiRequestId ??= `req_${randomUUID()}`), failure);
}