🪛 markdown renderer

lib/markdown.ts

@@ -0,0 +1,149 @@
+import fs from 'fs';
+import path from 'path';
+import matter from 'gray-matter';
+import { FrontMatter, Post } from './types/frontmatter';
+import { generateExcerpt } from './utils';
+
+const POSTS_PATH = path.join(process.cwd(), 'content', 'blog');
+
+export function sanitizePath(inputPath: string): string {
+  const normalized = path.normalize(inputPath).replace(/^(\.\.[\/\\])+/, '');
+  if (normalized.includes('..') || path.isAbsolute(normalized)) {
+    throw new Error('Invalid path');
+  }
+  return normalized;
+}
+
+export function calculateReadingTime(content: string): number {
+  const wordsPerMinute = 200;
+  const words = content.trim().split(/\s+/).length;
+  return Math.ceil(words / wordsPerMinute);
+}
+
+export function validateFrontmatter(data: any): FrontMatter {
+  if (!data.title || typeof data.title !== 'string') {
+    throw new Error('Invalid title');
+  }
+  if (!data.description || typeof data.description !== 'string') {
+    throw new Error('Invalid description');
+  }
+  if (!data.date || typeof data.date !== 'string') {
+    throw new Error('Invalid date');
+  }
+  if (!data.author || typeof data.author !== 'string') {
+    throw new Error('Invalid author');
+  }
+  if (!data.category || typeof data.category !== 'string') {
+    throw new Error('Invalid category');
+  }
+  if (!Array.isArray(data.tags) || data.tags.length === 0 || data.tags.length > 3) {
+    throw new Error('Tags must be array with 1-3 items');
+  }
+
+  return {
+    title: data.title,
+    description: data.description,
+    date: data.date,
+    author: data.author,
+    category: data.category,
+    tags: data.tags,
+    image: data.image,
+    draft: data.draft || false,
+  };
+}
+
+export function getPostBySlug(slug: string[]): Post {
+  const sanitized = slug.map(s => sanitizePath(s));
+  const fullPath = path.join(POSTS_PATH, ...sanitized) + '.md';
+
+  if (!fs.existsSync(fullPath)) {
+    throw new Error('Post not found');
+  }
+
+  const fileContents = fs.readFileSync(fullPath, 'utf8');
+  const { data, content } = matter(fileContents);
+  const frontmatter = validateFrontmatter(data);
+
+  return {
+    slug: sanitized.join('/'),
+    frontmatter,
+    content,
+    readingTime: calculateReadingTime(content),
+    excerpt: generateExcerpt(content),
+  };
+}
+
+export function getAllPosts(includeContent = false): Post[] {
+  const posts: Post[] = [];
+
+  function walkDir(dir: string, prefix = ''): void {
+    const files = fs.readdirSync(dir);
+
+    for (const file of files) {
+      const filePath = path.join(dir, file);
+      const stat = fs.statSync(filePath);
+
+      if (stat.isDirectory()) {
+        walkDir(filePath, prefix ? `${prefix}/${file}` : file);
+      } else if (file.endsWith('.md')) {
+        const slug = prefix ? `${prefix}/${file.replace(/\.md$/, '')}` : file.replace(/\.md$/, '');
+        try {
+          const post = getPostBySlug(slug.split('/'));
+          if (!post.frontmatter.draft) {
+            posts.push(includeContent ? post : { ...post, content: '' });
+          }
+        } catch (error) {
+          console.error(`Error loading post ${slug}:`, error);
+        }
+      }
+    }
+  }
+
+  if (fs.existsSync(POSTS_PATH)) {
+    walkDir(POSTS_PATH);
+  }
+
+  return posts.sort((a, b) => new Date(b.frontmatter.date).getTime() - new Date(a.frontmatter.date).getTime());
+}
+
+export function getRelatedPosts(currentSlug: string, category: string, tags: string[], limit = 3): Post[] {
+  const allPosts = getAllPosts(false);
+
+  const scored = allPosts
+    .filter(post => post.slug !== currentSlug)
+    .map(post => {
+      let score = 0;
+      if (post.frontmatter.category === category) score += 3;
+      score += post.frontmatter.tags.filter(tag => tags.includes(tag)).length * 2;
+      return { post, score };
+    })
+    .filter(({ score }) => score > 0)
+    .sort((a, b) => b.score - a.score);
+
+  return scored.slice(0, limit).map(({ post }) => post);
+}
+
+export function getAllPostSlugs(): string[][] {
+  const slugs: string[][] = [];
+
+  function walkDir(dir: string, prefix: string[] = []): void {
+    const files = fs.readdirSync(dir);
+
+    for (const file of files) {
+      const filePath = path.join(dir, file);
+      const stat = fs.statSync(filePath);
+
+      if (stat.isDirectory()) {
+        walkDir(filePath, [...prefix, file]);
+      } else if (file.endsWith('.md')) {
+        slugs.push([...prefix, file.replace(/\.md$/, '')]);
+      }
+    }
+  }
+
+  if (fs.existsSync(POSTS_PATH)) {
+    walkDir(POSTS_PATH);
+  }
+
+  return slugs;
+}