export type CurriculumWeek = {
  week: number;
  title: string;
  tags: string[];
  progress: number;
  state: string;
  topics: string[];
  duration: string;
  github: string;
  detail: {
    overview: string;
    learningSteps?: Array<{
      title: string;
      description: string;
      videoEnabled?: boolean;
      videoUrl?: string;
      concepts?: string[];
    }>;
    topicDetails: string[];
    topicVideoUrls?: string[];
    practiceContents?: Array<{
      title: string;
      description: string;
    }>;
    references?: CurriculumReference[];
    exampleCodes?: CurriculumReference[];
    deliverable: string;
    requiresSourceSubmission: boolean;
  };
  modules?: CurriculumModule[];
  visualizationPlatforms?: CurriculumVisualizationPlatform[];
};

export type CurriculumModule = {
  id: string;
  sortOrder: number;
  category: string;
  name: string;
  folderName: string;
  templateRepositoryUrl?: string | null;
  dockerImage?: string | null;
  enabled?: boolean;
};

export type CurriculumReference = {
  id: string;
  kind?: string;
  title: string;
  description?: string | null;
  fileName: string;
  contentType?: string | null;
  fileSizeBytes?: number | string | null;
  week?: number | string | null;
  weekNumber?: number | string | null;
  downloadUrl: string;
  createdAt?: string;
};

export type CurriculumVisualizationPlatform = {
  key: string;
  type: string;
  displayName: string;
  description?: string | null;
  config?: unknown;
};

export type CurriculumTagOption = {
  key: string;
  label: string;
};

export type InstructorCurriculumResponse = {
  course: {
    id: string;
    title: string;
    subtitle?: string | null;
    description?: string | null;
    organizationName: string;
  } | null;
  weeks: CurriculumWeek[];
  setting: {
    groupId?: string | null;
    activeWeek: number;
    activeLearningStep?: string | null;
  } | null;
  tagOptions?: CurriculumTagOption[];
  visualizationPlatforms?: CurriculumVisualizationPlatform[];
};

const LMS_API_BASE_URL = (import.meta.env.VITE_API_BASE_URL ?? 'http://localhost:4400/api').replace(/\/+$/, '');

export async function getInstructorCurriculum(accessToken: string, groupId?: string | null, courseId?: string | null): Promise<InstructorCurriculumResponse> {
  const params = new URLSearchParams();
  if (groupId) params.set('groupId', groupId);
  if (courseId) params.set('courseId', courseId);
  const query = params.toString() ? `?${params.toString()}` : '';
  const response = await fetch(`${LMS_API_BASE_URL}/instructor/curriculum${query}`, {
    headers: {
      Authorization: `Bearer ${accessToken}`,
    },
  });

  if (!response.ok) throw new Error(`커리큘럼을 불러오지 못했습니다. (${response.status})`);
  return response.json() as Promise<InstructorCurriculumResponse>;
}

export async function updateInstructorCurriculum(
  accessToken: string,
  input: {
    courseId?: string | null;
    groupId?: string | null;
    activeWeek: number;
    activeLearningStep?: string | null;
    applyToStudents?: boolean;
    completed?: boolean;
    tagLabel?: string;
    title?: string;
    duration?: string;
    overview?: string;
    deliverable?: string;
    requiresSourceSubmission?: boolean;
    topics?: string[];
    learningSteps?: Array<{
      title?: string;
      description?: string;
      videoEnabled?: boolean;
      videoUrl?: string;
      concepts?: string[];
    }>;
    topicDetails?: string[];
    topicVideoUrls?: string[];
    practiceContents?: Array<{
      title?: string;
      description?: string;
    }>;
    disabledModuleIds?: string[];
    visualizationPlatformKeys?: string[];
  },
): Promise<InstructorCurriculumResponse> {
  const response = await fetch(`${LMS_API_BASE_URL}/instructor/curriculum`, {
    method: 'PUT',
    headers: {
      Authorization: `Bearer ${accessToken}`,
      'content-type': 'application/json',
    },
    body: JSON.stringify(input),
  });

  if (!response.ok) {
    const payload = await response.json().catch((): null => null);
    const message =
      payload && typeof payload === 'object' && 'message' in payload
        ? String(payload.message)
        : `커리큘럼을 적용하지 못했습니다. (${response.status})`;
    throw new Error(message);
  }

  return response.json() as Promise<InstructorCurriculumResponse>;
}

export async function deleteInstructorCurriculumWeek(
  accessToken: string,
  week: number,
): Promise<InstructorCurriculumResponse> {
  const response = await fetch(`${LMS_API_BASE_URL}/instructor/curriculum/weeks/${week}`, {
    method: 'DELETE',
    headers: {
      Authorization: `Bearer ${accessToken}`,
    },
  });

  if (!response.ok) {
    const payload = await response.json().catch((): null => null);
    const message =
      payload && typeof payload === 'object' && 'message' in payload
        ? String(payload.message)
        : `주차를 삭제하지 못했습니다. (${response.status})`;
    throw new Error(message);
  }

  return response.json() as Promise<InstructorCurriculumResponse>;
}

export async function uploadCurriculumReference(
  accessToken: string,
  input: {
    courseId?: string | null;
    week: number;
    title?: string;
    file: File;
  },
): Promise<InstructorCurriculumResponse> {
  const formData = new FormData();
  formData.set('file', input.file);
  formData.set('courseId', input.courseId ?? '');
  formData.set('title', input.title?.trim() || input.file.name);

  const response = await fetch(`${LMS_API_BASE_URL}/instructor/curriculum/weeks/${input.week}/references`, {
    method: 'POST',
    headers: {
      Authorization: `Bearer ${accessToken}`,
    },
    body: formData,
  });

  if (!response.ok) {
    const payload = await response.json().catch((): null => null);
    const message =
      payload && typeof payload === 'object' && 'message' in payload
        ? String(payload.message)
        : `참고자료를 업로드하지 못했습니다. (${response.status})`;
    throw new Error(message);
  }

  return response.json() as Promise<InstructorCurriculumResponse>;
}

export async function uploadCurriculumExampleCode(
  accessToken: string,
  input: {
    courseId?: string | null;
    week: number;
    title?: string;
    file: File;
  },
): Promise<InstructorCurriculumResponse> {
  const formData = new FormData();
  formData.set('file', input.file);
  formData.set('courseId', input.courseId ?? '');
  formData.set('title', input.title?.trim() || input.file.name);

  const response = await fetch(`${LMS_API_BASE_URL}/instructor/curriculum/weeks/${input.week}/example-codes`, {
    method: 'POST',
    headers: {
      Authorization: `Bearer ${accessToken}`,
    },
    body: formData,
  });

  if (!response.ok) {
    const payload = await response.json().catch((): null => null);
    const message =
      payload && typeof payload === 'object' && 'message' in payload
        ? String(payload.message)
        : `예제 코드를 업로드하지 못했습니다. (${response.status})`;
    throw new Error(message);
  }

  return response.json() as Promise<InstructorCurriculumResponse>;
}

export async function deleteCurriculumReference(
  accessToken: string,
  referenceId: string,
  courseId?: string | null,
): Promise<InstructorCurriculumResponse> {
  const query = courseId ? `?courseId=${encodeURIComponent(courseId)}` : '';
  const response = await fetch(`${LMS_API_BASE_URL}/instructor/curriculum/references/${referenceId}${query}`, {
    method: 'DELETE',
    headers: {
      Authorization: `Bearer ${accessToken}`,
    },
  });

  if (!response.ok) {
    const payload = await response.json().catch((): null => null);
    const message =
      payload && typeof payload === 'object' && 'message' in payload
        ? String(payload.message)
        : `참고자료를 삭제하지 못했습니다. (${response.status})`;
    throw new Error(message);
  }

  return response.json() as Promise<InstructorCurriculumResponse>;
}