const fs = require('fs');
const path = require('path');

// 读取模板
const templatePath = path.join(__dirname, 'template.html');
const template = fs.readFileSync(templatePath, 'utf-8');

// 读取章节索引
const indexPath = path.join(__dirname, 'data/chapters-index.json');
const indexData = JSON.parse(fs.readFileSync(indexPath, 'utf-8'));
const chaptersIndex = indexData.chapters;

// 生成侧边栏章节列表
function generateSidebarChapters(currentId, chapters) {
    const start = Math.max(1, currentId - 30);
    const end = Math.min(chapters.length, currentId + 30);
    let html = '';
    
    for (let i = start; i <= end; i++) {
        const chapter = chapters.find(c => c.id === i);
        if (chapter) {
            const isCurrent = i === currentId ? 'current' : '';
            html += `<a href="chapter-${i}.html" class="sidebar-chapter ${isCurrent}">第${i}章：${chapter.title}</a>\n`;
        }
    }
    
    return html;
}

// 处理章节内容（转换JSON格式为HTML段落）
function processContent(content) {
    // 分割成段落
    const paragraphs = content.split('\n').filter(p => p.trim());
    let html = '';
    
    for (const para of paragraphs) {
        const trimmed = para.trim();
        if (trimmed.startsWith('---')) {
            // 分隔线转为特殊标记
            html += `<p style="text-align: center; color: var(--text-secondary); text-indent: 0;">···</p>\n`;
        } else if (trimmed.startsWith('（') && trimmed.endsWith('）')) {
            // 结尾标记
            html += `<p style="text-align: center; color: var(--text-secondary); text-indent: 0; margin-top: 2em;">${trimmed}</p>\n`;
        } else {
            html += `<p>${trimmed}</p>\n`;
        }
    }
    
    return html;
}

// 生成HTML页面
function generateChapterHtml(chapter, chapters) {
    const prevChapter = chapter.id > 1 ? `chapter-${chapter.id - 1}.html` : '#';
    const nextChapter = chapter.id < chapters.length ? `chapter-${chapter.id + 1}.html` : '#';
    const prevDisabled = chapter.id <= 1 ? 'disabled' : '';
    const nextDisabled = chapter.id >= chapters.length ? 'disabled' : '';
    
    let html = template;
    html = html.replace('{{CHAPTER_ID}}', chapter.id);
    html = html.replace('{{CHAPTER_NUMBER}}', `Chapter ${chapter.id}`);
    html = html.replace('{{CHAPTER_TITLE}}', chapter.title);
    html = html.replace('{{CHAPTER_CONTENT}}', processContent(chapter.content));
    html = html.replace('{{PREV_CHAPTER}}', prevChapter);
    html = html.replace('{{NEXT_CHAPTER}}', nextChapter);
    html = html.replace('{{PREV_DISABLED}}', prevDisabled);
    html = html.replace('{{NEXT_DISABLED}}', nextDisabled);
    html = html.replace('{{SIDEBAR_CHAPTERS}}', generateSidebarChapters(chapter.id, chapters));
    
    return html;
}

// 主函数
function main() {
    const chaptersDir = path.join(__dirname, 'chapters');
    const dataDir = path.join(__dirname, 'data');
    
    // 确保目录存在
    if (!fs.existsSync(chaptersDir)) {
        fs.mkdirSync(chaptersDir, { recursive: true });
    }
    
    let generated = 0;
    let skipped = 0;
    
    for (const chapterMeta of chaptersIndex) {
        const outputPath = path.join(chaptersDir, `chapter-${chapterMeta.id}.html`);
        const jsonPath = path.join(dataDir, `chapter-${chapterMeta.id}.json`);
        
        // 检查JSON文件是否存在
        if (!fs.existsSync(jsonPath)) {
            console.log(`⏭️ 跳过: chapter-${chapterMeta.id}.html (JSON不存在)`);
            skipped++;
            continue;
        }
        
        try {
            // 读取完整章节内容
            const jsonData = JSON.parse(fs.readFileSync(jsonPath, 'utf-8'));
            const chapter = {
                id: chapterMeta.id,
                title: jsonData.title || chapterMeta.title,
                content: jsonData.content || ''
            };
            
            const html = generateChapterHtml(chapter, chaptersIndex);
            fs.writeFileSync(outputPath, html, 'utf-8');
            generated++;
            console.log(`✅ 生成: chapter-${chapter.id}.html (${chapter.title})`);
        } catch (err) {
            console.error(`❌ 错误: chapter-${chapterMeta.id}.html - ${err.message}`);
            skipped++;
        }
    }
    
    console.log(`\n📊 统计: 生成 ${generated} 个文件, 跳过 ${skipped} 个`);
}

main();