✅ Refactor Plan for Markdown Anchor Linking

🧠 1. Understand the Problem

[link](#heading) links rely on corresponding HTML elements having id="heading".

marked.js by default doesn’t add id attributes to headings unless configured.

Your headings might be missing ids or may not match the expected format (e.g., space vs. hyphen mismatch).



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🧱 2. Refactor Outline

🔧 Step 1: Customize Marked Renderer

Use a custom Renderer in marked.js to automatically generate slugified ids for headings:

import { marked } from "marked";
import slugify from "slugify";

const renderer = new marked.Renderer();

renderer.heading = (text, level) => {
  const slug = slugify(text, { lower: true, strict: true });
    return `<h${level} id="${slug}">${text}</h${level}>`;
    };

    marked.setOptions({ renderer });

    > ✅ You can use slugify or write your own slug generator if needed.




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    🧩 Step 2: Normalize Anchor Links in Markdown

    Ensure links like [My Paragraph](#my-paragraph) are slugified the same way as the ids:

    Ensure slugify rules match exactly with those used in the heading renderer.

    If links are auto-generated or user-written, you may want to validate or transform them in your rendering pipeline.



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    🧪 Step 3: Test Scroll Behavior

    If scrolling doesn't work as expected, make sure your links are:

    Properly rendered as <a href="#some-id">...</a>

    The target heading exists in the DOM at time of click (no lazy-loading issues).


    Check for any custom scroll behavior in your layout that may interfere (e.g., smooth scroll or offset handling for sticky headers).



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    💡 Optional Improvements

    ➕ Add Smooth Scrolling

    In _app.tsx or layout file:

    html {
      scroll-behavior: smooth;
      }

      🛑 Handle Scroll Offset (if using fixed/sticky headers)

      Add a little scroll offset with a custom scroll handler:

      useEffect(() => {
        const handler = (e: any) => {
            if (e.target.hash) {
                  e.preventDefault();
                        const id = e.target.hash.slice(1);
                              const element = document.getElementById(id);
                                    if (element) {
                                            const yOffset = -80; // adjust if you have a sticky header
                                                    const y = element.getBoundingClientRect().top + window.pageYOffset + yOffset;
                                                            window.scrollTo({ top: y, behavior: 'smooth' });
                                                                  }
                                                                      }
                                                                        };

                                                                          document.querySelectorAll('a[href^="#"]').forEach((el) =>
                                                                              el.addEventListener('click', handler)
                                                                                );

                                                                                  return () => {
                                                                                      document.querySelectorAll('a[href^="#"]').forEach((el) =>
                                                                                            el.removeEventListener('click', handler)
                                                                                                );
                                                                                                  };
                                                                                                  }, []);


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                                                                                                  📁 3. Folder/File Structure (Suggested)

                                                                                                  /lib
                                                                                                    markdown.ts         # marked.js config and renderer
                                                                                                    /pages
                                                                                                      /blog/[slug].tsx    # uses markdown.ts to render content


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                                                                                                      ✅ Summary Checklist

                                                                                                      Step	Task	Status

                                                                                                      1	Add custom heading renderer in marked.js	⬜
                                                                                                      2	Ensure consistent slugification	⬜
                                                                                                      3	Fix anchor tag rendering in links	⬜
                                                                                                      4	Add smooth scrolling / offset scroll fix	⬜
                                                                                                      5	Test across multiple headings & links	⬜



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