/**
 * 书籍生成模块 API
 */

import { request, get, post } from './request';

// ============ 类型定义 ============

export interface Book {
  id: string;
  userId?: number;
  title: string;
  subtitle?: string;
  description: string;
  targetAudience: string;
  style: string;
  bookScale?: string;
  totalChapters: number;
  estimatedWords: number;
  progress: number;
  chapters: Chapter[];
  outline?: BookOutline;
  metadata?: BookMetadata;
  error?: string;
  isPublished?: boolean;
  genStage?: BookGenStage;    // 线性阶段状态（替代旧 status 字段）
  failedStage?: string;       // 失败阶段
  createdAt: string;
  updatedAt: string;
}

export interface BookOutline {
  mainTheme: string;
  structureLogic: string;
  chapters: OutlineChapter[];
}

export interface OutlineSubsection {
  title: string;
  summary?: string;
}

export interface OutlineSection {
  title: string;
  summary: string;
  subsections?: OutlineSubsection[];
}

export interface OutlineChapter {
  number: number;
  title: string;
  summary: string;
  keyPoints: string[];
  estimatedWords: number;
  stories?: string[];
  sections?: OutlineSection[];
}

export interface Chapter {
  id: string;
  bookId: string;
  number: number;
  title: string;
  content: string;
  summary?: string;
  wordCount: number;
  audioUrl?: string;
  audioDuration?: number;
  audioStatus?: string;
  videoUrl?: string;
  videoDuration?: number;
  videoStatus?: string;
  contentStatus?: string;
  contentError?: string;
  error?: string;
  level?: number;            // 层级：1=章, 2=节, 3=小节
  parentId?: number | null;  // 父节点ID（null表示章）
  genStage?: ChapterGenStage;  // 线性阶段状态（替代旧 status 字段）
}

// ============ 线性阶段类型（与后端 stage-manager.ts 同步） ============

export type BookGenStage =
  | 'draft'
  | 'outlining'
  | 'outline_completed'
  | 'content_generating'
  | 'content_completed'
  | 'audio_generating'
  | 'audio_completed'
  | 'video_generating'
  | 'video_completed'
  | 'failed';

export type ChapterGenStage =
  | 'idle'
  | 'outline_completed'
  | 'content_generating'
  | 'content_completed'
  | 'audio_generating'
  | 'audio_completed'
  | 'video_generating'
  | 'video_completed'
  | 'failed';

export interface BookMetadata {
  author?: string;
  foreword?: string;
  afterword?: string;
}

export interface CreateBookRequest {
  title: string;
  subtitle?: string;
  description: string;
  targetAudience?: string;
  style?: string;
  bookScale?: string;
  bookType?: string;
  genLevel?: number;
  language?: string;
}

export interface ProgressResponse {
  bookId: string;
  progress: number;
  genStage?: string;
  completedChapters: number;
  totalChapters: number;
  currentTask?: {
    type: string;
    message: string;
  };
}

// ============ API 函数 ============

const BASE_URL = '/book-generator/langgraph';

/**
 * 创建书籍
 */
export async function createBook(data: CreateBookRequest): Promise<Book> {
  const result = await request<{ book: Book }>(`${BASE_URL}/books`, { method: 'POST', data: { ...data } });
  return result.book;
}

/**
 * 获取所有书籍
 */
export async function getBooks(): Promise<Book[]> {
  const result = await request<{ books: Book[] }>(`${BASE_URL}/books`);
  return result.books || [];
}

/**
 * 获取公开书籍列表（首页专用）
 */
export async function getPublicBooks(): Promise<Book[]> {
  const result = await request<{ books: Book[] }>(`${BASE_URL}/public-books`);
  return result.books || [];
}

/**
 * 获取书籍详情
 */
export async function getBook(id: string): Promise<Book> {
  const result = await request<{ book: Book }>(`${BASE_URL}/books/${id}`);
  return result.book;
}

/**
 * 获取单个章节详情（从专辑控制器获取，只返回单章节内容）
 */
export async function getChapter(chapterId: string): Promise<any> {
  return await request<any>(`/book-generator/books/chapters/${chapterId}`);
}

/**
 * 删除书籍
 */
export async function deleteBook(id: string): Promise<void> {
  await request(`${BASE_URL}/books/${id}`, { method: 'DELETE' });
}

/**
 * 生成大纲
 */
export async function generateOutline(id: string): Promise<BookOutline> {
  const result = await request<{ outline: BookOutline }>(`${BASE_URL}/books/${id}/outline`, { method: 'POST' });
  return result.outline;
}

/**
 * 生成单个章节
 */
export async function generateChapter(id: string, chapterNumber: number): Promise<Chapter> {
  const result = await request<{ chapter: Chapter }>(`${BASE_URL}/books/${id}/chapters`, {
    method: 'POST',
    data: { chapterNumber },
  });
  return result.chapter;
}

/**
 * 生成全部章节
 */
export async function generateAllChapters(id: string): Promise<Chapter[]> {
  const result = await request<{ chapters: Chapter[] }>(`${BASE_URL}/books/${id}/chapters`, { method: 'POST' });
  return result.chapters || [];
}

/**
 * 生成前言
 */
export async function generateForeword(id: string): Promise<string> {
  const result = await request<{ foreword: string }>(`${BASE_URL}/books/${id}/foreword`, { method: 'POST' });
  return result.foreword;
}

/**
 * 生成后记
 */
export async function generateAfterword(id: string): Promise<string> {
  const result = await request<{ afterword: string }>(`${BASE_URL}/books/${id}/afterword`, { method: 'POST' });
  return result.afterword;
}

// ============ 交互式生成 API ============

/**
 * 启动深度规划（异步，立即返回）
 */
export async function startInteractivePlan(bookId: string, feedback?: string): Promise<{ genStage: string }> {
  const result = await request<any>(`${BASE_URL}/books/${bookId}/interactive/plan`, {
    method: 'POST',
    data: feedback ? { feedback } : undefined,
    config: { timeout: 10000 },
  });
  return result;
}

/**
 * 轮询 Plan 生成状态与结果
 * 返回 { genStage, rawPlan?, planData?, error? }
 */
export async function pollInteractivePlan(bookId: string): Promise<any> {
  const result = await request<any>(`${BASE_URL}/books/${bookId}/interactive/plan`, { method: 'GET', config: { timeout: 5000 } });
  return result;
}

/**
 * 保存用户修改后的 Plan
 */
export async function updateInteractivePlan(bookId: string, plan: string): Promise<void> {
  await request(`${BASE_URL}/books/${bookId}/interactive/plan`, { method: 'PUT', data: { plan } });
}

/**
 * 启动大纲生成（异步，立即返回）
 */
export async function startInteractiveOutline(bookId: string): Promise<{ genStage: string }> {
  const result = await request<any>(`${BASE_URL}/books/${bookId}/interactive/outline`, { method: 'POST', config: { timeout: 10000 } });
  return result;
}

/**
 * 轮询 Outline 生成状态与结果
 * 返回 { genStage, rawOutline?, outlineData?, error? }
 */
export async function pollInteractiveOutline(bookId: string): Promise<any> {
  const result = await request<any>(`${BASE_URL}/books/${bookId}/interactive/outline`, { method: 'GET', config: { timeout: 5000 } });
  return result;
}

/**
 * 保存用户修改后的大纲
 */
export async function updateInteractiveOutline(bookId: string, outline: any): Promise<void> {
  await request(`${BASE_URL}/books/${bookId}/interactive/outline`, { method: 'PUT', data: { outline } });
}

/**
 * 运行内容生成（交互模式 Step 4）
 */
export async function generateInteractiveContent(bookId: string): Promise<{ bookId: string; genStage: string; jobId?: string }> {
  const result = await request<any>(`${BASE_URL}/books/${bookId}/interactive/generate`, { method: 'POST', config: { timeout: 10000 } });
  return result;
}

/**
 * 创建书籍但不自动生成（交互模式 Step 1 使用）
 */
export async function createBookInteractive(data: CreateBookRequest): Promise<Book> {
  const result = await request<{ book: Book }>(`${BASE_URL}/books`, { method: 'POST', data: { ...data, immediateGenerate: false } });
  return result.book;
}

/**
 * 获取完整书籍内容
 */
export async function getFullContent(id: string): Promise<string> {
  const result = await request<{ content: string }>(`${BASE_URL}/books/${id}/full-content`);
  return result.content;
}

/**
 * 获取生成进度
 */
export async function getProgress(id: string): Promise<ProgressResponse> {
  const result = await request<ProgressResponse>(`${BASE_URL}/books/${id}/progress`);
  return result;
}

/**
 * 一键生成整本书
 */
export async function generateBook(
  id: string,
  options?: {
    generateForeword?: boolean;
    generateAfterword?: boolean;
  }
): Promise<{
  success: boolean;
  completedChapters: number;
  failedChapters: number;
  foreword?: string;
  afterword?: string;
  errors: string[];
}> {
  const result = await request<{
    success: boolean;
    completedChapters: number;
    failedChapters: number;
    foreword?: string;
    afterword?: string;
    errors: string[];
  }>(`${BASE_URL}/books/${id}/generate`, {
    method: 'POST',
    data: options || {},
  });
  return result;
}

/**
 * 工作流状态
 */
export interface WorkflowProgress {
  phase: 'planning' | 'writing' | 'supplement' | 'done';
  currentNode: string;
  currentChapter: number;
  completedChapters: number;
  totalChapters: number;
  pendingChapters: number[];
  failedChapters: number[];
  progress: number;
}

/**
 * 获取工作流状态
 */
export async function getWorkflowProgress(bookId: string): Promise<WorkflowProgress | null> {
  const result = await request<WorkflowProgress>(`${BASE_URL}/workflow/${bookId}`);
  return result;
}

// ============ LangGraph API ============

/**
 * 使用 LangGraph 创建并生成书籍
 */
export async function createBookWithLangGraph(data: {
  title: string;
  description: string;
  totalChapters?: number;
}): Promise<{ bookId: string; taskId: string }> {
  const result = await request<{ bookId: string; taskId: string }>(`${BASE_URL}/books`, {
    method: 'POST',
    data,
  });
  return result;
}

/**
 * 使用 LangGraph 生成已有书籍
 */
export async function generateWithLangGraph(bookId: string): Promise<{ bookId: string; taskId: string }> {
  const result = await request<{ bookId: string; taskId: string }>(`${BASE_URL}/books/${bookId}/generate`, {
    method: 'POST',
  });
  return result;
}

// ============ 音频生成 API ============

/**
 * 生成单个章节音频（实际调用批量生成，后端会生成所有章节）
 */
export async function generateChapterAudio(
  bookId: string,
  chapterNumber: number,
  voiceId: string = 'voice_01'
): Promise<{ taskId: string; totalSubsections: number }> {
  // 后端只有批量生成API，所以调用批量生成
  const result = await request<{ taskId: string; totalSubsections: number }>(
    `${BASE_URL}/books/${bookId}/audio`,
    {
      method: 'POST',
      data: { voiceId },
    }
  );
  return result;
}

/**
 * 批量生成书籍所有章节音频
 */
export async function generateAllChaptersAudio(
  bookId: string,
  voiceId: string = 'voice_01'
): Promise<{ taskId: string; totalChapters: number }> {
  const result = await request<{ taskId: string; totalSubsections: number }>(
    `${BASE_URL}/books/${bookId}/audio`,
    {
      method: 'POST',
      data: { voiceId },
    }
  );
  return {
    taskId: result.taskId,
    totalChapters: result.totalSubsections,
  };
}

// ============ 视频生成 API ============

/**
 * 取消书籍所有章节音频生成
 */
export async function cancelAudioGeneration(
  bookId: string
): Promise<{ cancelledCount: number; rolledBackChapters: number[] }> {
  const result = await request<{ cancelledCount: number; rolledBackChapters: number[] }>(
    `${BASE_URL}/books/${bookId}/audio/cancel`,
    { method: 'POST' }
  );
  return result;
}

/**
 * 生成单个章节视频（从音频转视频）
 */
export async function generateChapterVideo(
  bookId: string,
  chapterId: string | number
): Promise<{ projectId: number; chapterId: string }> {
  const result = await request<{ projectId: number; chapterId: string }>(
    `${BASE_URL}/books/${bookId}/chapters/${chapterId}/video`,
    {
      method: 'POST',
    }
  );
  return result;
}

/**
 * 批量生成书籍所有章节视频
 */
export async function generateAllChaptersVideo(
  bookId: string
): Promise<{ taskId: string; totalChapters: number }> {
  const result = await request<{ taskId: string; totalChapters: number }>(
    `${BASE_URL}/books/${bookId}/videos`,
    {
      method: 'POST',
    }
  );
  return result;
}

/**
 * 合并叶节点音频到上级章节
 */
export async function mergeChapterAudios(
  bookId: string
): Promise<{ taskId: string; processedParents: number; totalLeafNodes: number }> {
  const result = await request<{ taskId: string; processedParents: number; totalLeafNodes: number }>(
    `${BASE_URL}/books/${bookId}/merge-audio`,
    {
      method: 'POST',
    }
  );
  return result;
}

/**
 * 合并叶节点视频到上级章节
 */
export async function mergeChapterVideos(
  bookId: string
): Promise<{ taskId: string; processedParents: number; totalLeafNodes: number }> {
  const result = await request<{ taskId: string; processedParents: number; totalLeafNodes: number }>(
    `${BASE_URL}/books/${bookId}/merge-video`,
    {
      method: 'POST',
    }
  );
  return result;
}

/**
 * 获取书籍音频生成状态（用于轮询）
 */
export async function getAudioStatus(bookId: string): Promise<{
  bookId: string;
  total: number;
  completed: number;
  pending: number;
  allCompleted: boolean;
}> {
  const result = await request<{
    bookId: string;
    total: number;
    completed: number;
    pending: number;
    allCompleted: boolean;
  }>(`${BASE_URL}/books/${bookId}/audio-status`);
  return result;
}

/**
 * 获取书籍视频生成状态（用于轮询）
 */
export async function getVideoStatus(bookId: string): Promise<{
  bookId: string;
  total: number;
  completed: number;
  pending: number;
  allCompleted: boolean;
}> {
  const result = await request<{
    bookId: string;
    total: number;
    completed: number;
    pending: number;
    allCompleted: boolean;
  }>(`${BASE_URL}/books/${bookId}/video-status`);
  return result;
}

/**
 * 重新生成单个章节内容（仅叶节点）
 */
export async function regenerateChapterContent(
  bookId: string,
  chapterId: number
): Promise<{ chapterId: number; jobId: string }> {
  const result = await request<{ chapterId: number; jobId: string }>(
    `${BASE_URL}/books/${bookId}/chapters/${chapterId}/regenerate`,
    { method: 'POST' }
  );
  return result;
}

/**
 * 重新生成单个章节音频（仅叶节点）
 */
export async function regenerateChapterAudio(
  bookId: string,
  chapterId: number
): Promise<{ chapterId: number }> {
  const result = await request<{ chapterId: number }>(
    `${BASE_URL}/books/${bookId}/chapters/${chapterId}/regenerate-audio`,
    { method: 'POST' }
  );
  return result;
}

// ============ 书籍发布 API ============

/**
 * 切换书籍公开状态
 */
export async function toggleBookPublish(bookId: string): Promise<{ isPublished: boolean }> {
  const result = await request<{ isPublished: boolean }>(
    `${BASE_URL}/books/${bookId}/publish`,
    { method: 'PUT' }
  );
  return result;
}

// ============ 阶段状态辅助函数（与后端 stage-manager.ts 同步） ============

/**
 * 获取书籍阶段的用户可读描述
 */
export function getBookStageDescription(genStage?: string): string {
  if (!genStage) return '未知';
  switch (genStage) {
    case 'draft': return '草稿';
    case 'outlining': return '正在生成大纲...';
    case 'outline_completed': return '大纲已完成';
    case 'content_generating': return '正在生成内容...';
    case 'content_completed': return '内容已完成，等待生成音频';
    case 'audio_generating': return '正在生成音频...';
    case 'audio_completed': return '音频已完成，等待生成视频';
    case 'video_generating': return '正在生成视频...';
    case 'video_completed': return '全部完成 ✓';
    case 'failed': return '生成失败';
    default: return genStage;
  }
}

/**
 * 获取章节阶段的用户可读描述
 */
export function getChapterStageDescription(genStage?: string): string {
  if (!genStage) return '待生成';
  switch (genStage) {
    case 'idle': return '待生成';
    case 'outline_completed': return '大纲完成';
    case 'content_generating': return '生成中';
    case 'content_completed': return '内容完成';
    case 'audio_generating': return '生成音频中';
    case 'audio_completed': return '音频完成';
    case 'video_generating': return '生成视频中';
    case 'video_completed': return '已完成';
    case 'failed': return '失败';
    default: return genStage;
  }
}

/**
 * 判断书籍是否需要显示"生成音频"按钮
 */
export function needsAudioGeneration(genStage?: string): boolean {
  return genStage === 'content_completed';
}

/**
 * 判断书籍是否需要显示"生成视频"按钮
 */
export function needsVideoGeneration(genStage?: string): boolean {
  return genStage === 'audio_completed';
}

/**
 * 判断书籍是否全部完成（最终态）
 */
export function isBookFullyCompleted(genStage?: string): boolean {
  return genStage === 'video_completed';
}

/**
 * 获取书籍完整信息（用于编辑）
 */
export async function getBookForEdit(id: string): Promise<any> {
  return await request<any>(`/book-generator/books/${id}`);
}

/**
 * 更新书籍基础信息
 */
export async function updateBook(id: string, data: {
  title?: string;
  description?: string;
  coverUrl?: string;
  targetAudience?: string;
  style?: string;
  bookScale?: string;
}): Promise<{ id: number; title: string }> {
  return post(`/book-generator/books/${id}`, data);
}