/** * Book Content Generator Routes * * Generate complete book content with AI, including chapters, sections, and images. * Similar pattern to Landing Page Generator - async job-based generation with * MongoDB persistence for generated content. * * POST /generate — start async book content generation * GET /status/:jobId — poll job status * GET /generated-content/:bookId — get persisted generation status & metadata * GET /preview/:bookId — preview generated HTML content * GET /download/:bookId — download generated book (HTML or DOCX) * DELETE /generated-content/:bookId — clear generation data for retry */ import express, { Request, Response } from 'express'; import { authenticate } from '../middleware/auth'; import { requirePermission } from '../middleware/permissions'; import { getModels } from '../models'; import { createJob, updateJobProgress, completeJob, failJob, getJob } from '../services/aiContext/aiJobManager'; import { generateWithAI } from '../utils/aiProvider'; import fs from 'fs'; import path from 'path'; import PDFDocument from 'pdfkit'; import { Document, Packer, Paragraph, TextRun, HeadingLevel, AlignmentType, PageBreak, BorderStyle } from 'docx'; import { parseGeneratedBookHtml, renderBookPdf, renderBookDocx } from '../services/books/bookTypesetting'; const router = express.Router(); // ============================================ // TYPES // ============================================ interface GenerationConfig { bookType: string; writingStyle: string; toneOfVoice: string; contentDepth: string; imagesEnabled: boolean; imageStyle: string; imageAspect: string; outputFormat: string; visualIdentity?: { mode: string; primaryColor?: string; secondaryColor?: string; accentColor?: string; headingFont?: string; bodyFont?: string; visualVibe?: string; }; formatting?: { chapterLayout: string; lessonLayout: string; headingsHierarchy: boolean; tables: boolean; calloutBoxes: boolean; codeBlocks: boolean; quotes: boolean; tipsNotes: boolean; exercises: boolean; quizzes: boolean; summaries: boolean; }; aiInstructions?: { systemInstructions: string; writingConstraints: string; dosDonts: string; additionalGuidance: string; outputFormat: string; }; } interface ChapterInput { id?: string; _id?: string; title: string; description?: string; content?: string; learningObjectives?: string[]; keyTakeaways?: string[]; status?: string; order: number; } interface SectionInput { id?: string; _id?: string; title: string; type?: string; content?: string; keyPoints?: string[]; examples?: string[]; quotes?: string[]; status?: string; order: number; } // ============================================ // LAYOUT & FORMATTING DEFAULTS // ============================================ /** * The layout the wizard starts from. Kept in step with the AI Prompt step's * DEFAULT_CONFIG so a generation that never saw that step still produces a * properly structured book instead of an unformatted one. */ const DEFAULT_FORMATTING = { chapterLayout: 'traditional', lessonLayout: 'standard', headingsHierarchy: true, tables: true, calloutBoxes: true, codeBlocks: true, quotes: true, tipsNotes: true, exercises: true, quizzes: true, summaries: true, }; /** * Resolve the config to generate with: what the request sent, then what the book * was last generated with, then the defaults — merged per-section so a request * that carries only the basics does not drop the stored layout. */ function withLayoutDefaults(requestConfig: any, storedConfig: any): GenerationConfig { const req = requestConfig || {}; const stored = storedConfig || {}; return { ...stored, ...req, formatting: { ...DEFAULT_FORMATTING, ...(stored.formatting || {}), ...(req.formatting || {}), }, visualIdentity: { ...(stored.visualIdentity || {}), ...(req.visualIdentity || {}), }, aiInstructions: { ...(stored.aiInstructions || {}), ...(req.aiInstructions || {}), }, } as GenerationConfig; } /** * Turn the formatting switches into instructions the model can act on. * * Without this the wizard's layout choices were collected, sent, typed — and * then never reached a prompt, so every book came back in the model's own * default shape no matter what was selected. */ function buildFormattingInstructions(config: GenerationConfig): string { const f = { ...DEFAULT_FORMATTING, ...(config.formatting || {}) }; const chapterLayouts: Record = { traditional: 'Traditional — chapter title, introduction, body sections, then a conclusion.', modern: 'Modern — short hook, scannable subheadings, generous use of lists and pull-quotes.', academic: 'Academic — numbered sections, formal register, citations and a summary.', workbook: 'Workbook — instruction followed by exercises the reader completes.', narrative: 'Narrative — story-driven flow with minimal subheadings.', }; const lessonLayouts: Record = { standard: 'Standard — heading, explanation, example, takeaway.', 'objective-first': 'Objective-first — state the objective, teach it, then check understanding.', 'problem-solution': 'Problem-solution — pose the problem, work to the solution.', 'step-by-step': 'Step-by-step — numbered steps the reader follows in order.', 'case-study': 'Case study — context, actions taken, results, lessons.', }; const enabled: string[] = []; const disabled: string[] = []; const push = (on: boolean, text: string) => (on ? enabled : disabled).push(text); push(f.headingsHierarchy, 'a strict heading hierarchy (

for sections,

for sub-sections,

for minor points)'); push(f.tables, 'HTML elements for comparisons and structured data'); push(f.calloutBoxes, '
boxes for important notes'); push(f.codeBlocks, '
 blocks for code and commands');
  push(f.quotes, '
 for quotations');
  push(f.tipsNotes, '
 for tips and 
 for warnings');
  push(f.exercises, 'practical exercises for the reader');
  push(f.quizzes, 'short knowledge-check questions');
  push(f.summaries, 'a summary at the end of each chapter');

  return `## LAYOUT & FORMATTING (follow exactly)

**Chapter layout:** ${chapterLayouts[f.chapterLayout] || f.chapterLayout}
**Section layout:** ${lessonLayouts[f.lessonLayout] || f.lessonLayout}

**Use:**
${enabled.length ? enabled.map(e => `- ${e}`).join('\n') : '- Plain paragraphs only'}

${disabled.length ? `**Do NOT include:**\n${disabled.map(d => `- ${d}`).join('\n')}\n` : ''}
**Markup rules:**
- Return content as HTML fragments only — no , ,  or 


${generateCoverPage(book, chaptersWithSections)}
${generateTitlePage(book)}
${generateCopyrightPage(book)}
${generateTOCPage(book, chaptersWithSections)}
${generatePrefacePage(book)}
${generateAboutAuthorPage(book)}
${generateChapters(chaptersWithSections)}
${generateBackMatter(book)}

`;
}

function escapeHtml(str: string): string {
  return str
    .replace(/&/g, '&')
    .replace(//g, '>')
    .replace(/"/g, '"')
    .replace(/'/g, ''');
}

/** Authors are only printed when the book actually carries them. */
function authorLine(book: any): string {
  const names = Array.isArray(book.authors)
    ? book.authors.map((a: any) => (typeof a === 'string' ? a : a?.name)).filter(Boolean)
    : [];
  return names.join(', ');
}

function generateCoverPage(book: any, _chapters: any[]): string {
  const authors = authorLine(book);

  return `
  

    

      ${authors ? `
${escapeHtml(authors)}
` : ''}
      
${escapeHtml(book.title || 'Untitled')}

      

      ${book.subtitle ? `
${escapeHtml(book.subtitle)}
` : ''}
      ${book.description ? `
${escapeHtml(book.description)}
` : ''}
    

    ${book.publisher ? `
${escapeHtml(book.publisher)}
` : ''}
  
`;
}

function generateTitlePage(book: any): string {
  const authors = authorLine(book);
  return `
  

    

      
${escapeHtml(book.title || 'Untitled')}

      ${book.subtitle ? `
${escapeHtml(book.subtitle)}
` : ''}
      

      ${authors ? `
${escapeHtml(authors)}
` : ''}
    

    

      ${book.publisher ? `
${escapeHtml(book.publisher)}
` : ''}
      
${new Date().getFullYear()}

    

  
`;
}

function generateCopyrightPage(book: any): string {
  const authors = authorLine(book);
  const year = new Date().getFullYear();

  return `
  

    

      
Copyright © ${year}${authors ? ` ${escapeHtml(authors)}` : ''}

      
All rights reserved.

      
No part of this publication may be reproduced, distributed, or transmitted in any form or by any means, including photocopying, recording, or other electronic or mechanical methods, without the prior written permission of the publisher, except in the case of brief quotations embodied in critical reviews and certain other non-commercial uses permitted by copyright law.

      ${book.publisher ? `
${escapeHtml(book.publisher)}
` : ''}
      
First Edition

      ${book.isbn ? `
ISBN: ${escapeHtml(book.isbn)}
` : ''}
    

  
`;
}

function generateTOCPage(book: any, chapters: any[]): string {
  // Handle empty chapters array
  const chaptersList = chapters && chapters.length > 0 ? chapters : [];

  // No page numbers here: the HTML preview is a continuous document and has no
  // pagination to number. The exported PDF carries a contents page with real
  // folios taken from the typeset pages.
  const chaptersHtml = chaptersList.map((ch, i) => `
    
      ${i + 1}
      ${escapeHtml(ch.title || 'Untitled')}
    
  `).join('');

  const hasBackMatter =
    (book.glossary && book.glossary.length > 0) ||
    (book.references && book.references.length > 0) ||
    (book.appendix && book.appendix.length > 0);

  return `
  `;
}

function generatePrefacePage(book: any): string {
  if (!book.preface) return '';

  return `
  

    
Preface

    

    

      ${processContent(book.preface)}
    

  
`;
}

function generateAboutAuthorPage(book: any): string {
  if (!book.aboutAuthor) return '';

  const authors = book.authors?.[0];
  const authorName = authors?.name || authors || 'Author';
  const authorBio = book.aboutAuthor;

  return `
  

    
About the Author

    

    

      
${escapeHtml(authorName)}

      
${processContent(authorBio)}

    

  
`;
}

function generateChapters(chapters: any[]): string {
  // Handle empty chapters array
  if (!chapters || chapters.length === 0) {
    return `
    

      

        
No Chapters Yet

      

      

        
Add chapters to your book to see them here. Chapters will appear in the order they are defined in your book structure.

      

    
`;
  }

  return chapters.map((ch, i) => {
    const chapterId = ch.id || ch._id;
    const sections = ch.sections || [];
    const learningObjectives = ch.learningObjectives || [];
    const keyTakeaways = ch.keyTakeaways || [];
    const chapterTitle = ch.title || 'Untitled Chapter';
    const chapterDescription = ch.description || '';
    const chapterContent = ch.content || '';

    // No chapter-to-chapter navigation links: a book does not carry
    // "next / previous" controls on the page, and they printed into the export.
    return `
    

      

        
Chapter ${i + 1}

        
${escapeHtml(chapterTitle)}

        ${chapterDescription ? `
${escapeHtml(chapterDescription)}
` : ''}
      


      ${learningObjectives.length > 0 ? `
        

          
In This Chapter

          
    
            ${learningObjectives.map((obj: string) => `
  • ${escapeHtml(obj)}
    • `).join('')}
          

        

      ` : ''}

      

        ${chapterContent ? processContent(chapterContent) : `
          
Content will be generated here when you run AI generation.

        `}

        ${sections.length > 0 ? sections.map((sec: any, j: number) => {
          const sectionTitle = sec.title || 'Untitled Section';
          const sectionContent = sec.content || '';
          return `
          

            
${escapeHtml(sectionTitle)}

            ${sectionContent ? processContent(sectionContent) : `
              
Section content will be generated here.

            `}
            ${sec.keyPoints && sec.keyPoints.length > 0 ? `
              

                
Key Points

                
    
                  ${sec.keyPoints.map((kp: string) => `
  • ${escapeHtml(kp)}
    • `).join('')}
                

              

            ` : ''}
            ${sec.examples && sec.examples.length > 0 ? `
              
Examples

              ${sec.examples.map((ex: string) => `
${escapeHtml(ex)}
`).join('')}
            ` : ''}
          
`;
        }).join('') : ''}
      


      ${keyTakeaways.length > 0 ? `
        

          
Key Takeaways

          
    
            ${keyTakeaways.map((kt: string) => `
  • ${escapeHtml(kt)}
    • `).join('')}
          

        

      ` : ''}
    
`;
  }).join('\n');
}

function processContent(content: string): string {
  if (!content) return '';

  let cleaned = content.trim();

  // Models routinely wrap the requested HTML in a markdown fence despite being
  // asked not to. Left in place the fence markers render as literal text in the
  // middle of the book, so strip them before anything else.
  cleaned = cleaned.replace(/^```(?:html|markdown|md)?\s*\n?/i, '').replace(/\n?```\s*$/, '').trim();

  // A full document pasted into a chapter breaks the book's own layout: its
  //