From 0c79aff77b338facaa92b81deb4b0f96646a5bcc Mon Sep 17 00:00:00 2001
From: cupcakearmy <hi@nicco.io>
Date: Wed, 29 Dec 2021 18:52:26 +0100
Subject: [PATCH] sidepanel

---
 src/lib/components/ArticleOverview.svelte | 55 +++++++++++++++++++++++
 src/lib/components/WPAdapter.svelte       | 50 ++++++++++++---------
 2 files changed, 85 insertions(+), 20 deletions(-)
 create mode 100644 src/lib/components/ArticleOverview.svelte

diff --git a/src/lib/components/ArticleOverview.svelte b/src/lib/components/ArticleOverview.svelte
new file mode 100644
index 0000000..1dde117
--- /dev/null
+++ b/src/lib/components/ArticleOverview.svelte
@@ -0,0 +1,55 @@
+<script lang="ts" context="module">
+  export type ArticleHeading = {
+    text: string
+    hash: string
+    href: string
+    level: number
+  }
+</script>
+
+<script lang="ts">
+  export let headings: ArticleHeading[]
+</script>
+
+<div class="wrapper">
+  <b>Outline</b>
+  {#each headings as { text, level, href }}
+    <div style="margin-left: {level - 2}rem;">
+      <span>▶</span>
+      <a {href}>
+        {text}
+      </a>
+    </div>
+  {/each}
+</div>
+
+<style>
+  .wrapper {
+    margin: 2rem 0;
+  }
+
+  @media (min-width: 75rem) {
+    .wrapper {
+      margin: 0;
+      position: absolute;
+      top: 0;
+      left: 40rem;
+      width: max-content;
+    }
+  }
+
+  span {
+    font-size: 0.5em;
+    transform: translateY(-0.8em);
+    display: inline-block;
+  }
+
+  a {
+    height: 1.4em;
+    display: inline-block;
+    max-width: 20rem;
+    overflow: hidden;
+    white-space: nowrap;
+    text-overflow: ellipsis;
+  }
+</style>
diff --git a/src/lib/components/WPAdapter.svelte b/src/lib/components/WPAdapter.svelte
index 54b3066..a2b4f6d 100644
--- a/src/lib/components/WPAdapter.svelte
+++ b/src/lib/components/WPAdapter.svelte
@@ -1,14 +1,16 @@
 <script lang="ts">
   import hljs from 'highlight.js/lib/core'
-  import javascript from 'highlight.js/lib/languages/javascript'
-  import python from 'highlight.js/lib/languages/python'
-  import yaml from 'highlight.js/lib/languages/yaml'
-  import json from 'highlight.js/lib/languages/json'
   import bash from 'highlight.js/lib/languages/bash'
-  import docker from 'highlight.js/lib/languages/dockerfile'
-  import rust from 'highlight.js/lib/languages/rust'
   import css from 'highlight.js/lib/languages/css'
+  import docker from 'highlight.js/lib/languages/dockerfile'
+  import javascript from 'highlight.js/lib/languages/javascript'
+  import json from 'highlight.js/lib/languages/json'
+  import python from 'highlight.js/lib/languages/python'
+  import rust from 'highlight.js/lib/languages/rust'
   import typescript from 'highlight.js/lib/languages/typescript'
+  import yaml from 'highlight.js/lib/languages/yaml'
+  import { onMount } from 'svelte'
+  import ArticleOverview, { ArticleHeading } from './ArticleOverview.svelte'
 
   hljs.registerLanguage('javascript', javascript)
   hljs.registerLanguage('python', python)
@@ -20,15 +22,18 @@
   hljs.registerLanguage('css', css)
   hljs.registerLanguage('typescript', typescript)
 
-  import { onMount } from 'svelte'
-
   export let content: string
+  let headings: ArticleHeading[] | null = null
 
   function encodeTextToUrl(text: string): string {
     return text
-      .replace(/[^A-Za-z ]/, '')
-      .replace('/ +/', ' ')
-      .replace(' ', '-')
+      .toLowerCase()
+      .replace(/[^A-Za-z ]/g, '')
+      .replace(/ +/g, '-')
+  }
+
+  async function update(isDark: boolean) {
+    isDark ? await import('highlight.js/styles/github-dark.css') : await import('highlight.js/styles/github.css')
   }
 
   onMount(async () => {
@@ -37,16 +42,15 @@
     // Add anchor links to headers
     const selector = [1, 2, 3, 4, 5, 6].map((i) => `div.adapter h${i}`).join(', ')
     const elements = window.document.querySelectorAll(selector)
-    elements.forEach((el) => {
-      if (el.textContent) {
-        const hash = encodeTextToUrl(el.textContent)
-        el.innerHTML = `<a class="target-link" name="${hash}" href="${window.location.pathname}#${hash}">${el.innerHTML}</a>`
-      }
-    })
+    headings = Array.from(elements).map((element) => {
+      const text = element.textContent || ''
+      const hash = encodeTextToUrl(text)
+      const href = `${window.location.pathname}#${hash}`
+      const level = parseInt(element.tagName.slice(1))
 
-    async function update(isDark: boolean) {
-      isDark ? await import('highlight.js/styles/github-dark.css') : await import('highlight.js/styles/github.css')
-    }
+      element.innerHTML = `<a class="target-link" id="${hash}" href="${href}">${text}</a>`
+      return { text, hash, level, href }
+    })
 
     const match = window.matchMedia('(prefers-color-scheme: dark)')
     match.addEventListener('change', (e) => update(e.matches))
@@ -55,10 +59,16 @@
 </script>
 
 <div class="adapter">
+  {#if headings}
+    <ArticleOverview {headings} />
+  {/if}
   {@html content}
 </div>
 
 <style>
+  .adapter {
+    position: relative;
+  }
   div :global(.alignfull) {
     width: calc(100vw - 6em);
     margin-left: -2em;