From 4f630aadc84b2036d08f5445d1dbea92af55f628 Mon Sep 17 00:00:00 2001
From: Jori Lallo <jtlallo@gmail.com>
Date: Sun, 29 May 2016 15:22:33 -0700
Subject: [PATCH] Added anchors for document headings

---
 server/utils/markdown.js                  | 15 +++++++++++++-
 src/assets/icons/anchor.svg               |  1 +
 src/components/Document/Document.js       |  5 ++++-
 src/components/Document/Document.scss     | 25 +++++++++++++++++++++++
 src/scenes/DocumentScene/DocumentScene.js | 13 ++++++++++++
 5 files changed, 57 insertions(+), 2 deletions(-)
 create mode 100644 src/assets/icons/anchor.svg

diff --git a/server/utils/markdown.js b/server/utils/markdown.js
index a5d22d23..c5355456 100644
--- a/server/utils/markdown.js
+++ b/server/utils/markdown.js
@@ -1,14 +1,27 @@
+import slug from 'slug';
 import truncate from 'truncate-html';
 import marked, { Renderer } from 'marked';
 import highlight from 'highlight.js';
 
+slug.defaults.mode ='rfc3986';
+
 const renderer = new Renderer();
 renderer.code = (code, language) => {
   const validLang = !!(language && highlight.getLanguage(language));
   const highlighted = validLang ? highlight.highlight(language, code).value : code;
   return `<pre><code class="hljs ${language}">${highlighted}</code></pre>`;
 };
-
+renderer.heading = (text, level) => {
+  const headingSlug = slug(text);
+  return `
+    <h${level}>
+      <a name="${headingSlug}" class="anchor" href="#${headingSlug}">
+        <span class="header-link">&nbsp;</span>
+      </a>
+      ${text}
+    </h${level}>
+  `;
+},
 
 marked.setOptions({
   renderer: renderer,
diff --git a/src/assets/icons/anchor.svg b/src/assets/icons/anchor.svg
new file mode 100644
index 00000000..f9816437
--- /dev/null
+++ b/src/assets/icons/anchor.svg
@@ -0,0 +1 @@
+<svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" version="1.1" x="0px" y="0px" viewBox="0 0 100 125" enable-background="new 0 0 100 100" xml:space="preserve"><path d="M82.641,40.452L69.984,53.109c-1.164,1.164-3.054,1.164-4.218,0s-1.164-3.054,0-4.218l12.657-12.657  c3.489-3.489,3.489-9.165,0-12.657s-9.165-3.489-12.657,0L48.891,40.452c-1.035,1.059-5.955,6.702,0,12.657  c1.164,1.164,1.164,3.054,0,4.218s-3.054,1.164-4.218,0c-8.343-8.343-3.648-17.445,0-21.093l16.875-16.875  c5.814-5.814,15.279-5.814,21.093,0C88.455,25.173,88.452,34.638,82.641,40.452z M57.327,44.673c-1.164-1.164-3.054-1.164-4.218,0  c-1.164,1.164-1.164,3.054,0,4.218c5.955,5.955,1.035,11.595,0,12.657L36.234,78.423c-3.489,3.489-9.165,3.489-12.657,0  c-3.492-3.489-3.489-9.165,0-12.657l12.657-12.657c1.164-1.164,1.164-3.054,0-4.218s-3.054-1.164-4.218,0L19.359,61.548  c-5.814,5.814-5.814,15.279,0,21.093c5.814,5.814,15.279,5.814,21.093,0l16.875-16.875C60.975,62.118,65.67,53.013,57.327,44.673z"/></svg>
\ No newline at end of file
diff --git a/src/components/Document/Document.js b/src/components/Document/Document.js
index 8d87fadd..6a42f1f3 100644
--- a/src/components/Document/Document.js
+++ b/src/components/Document/Document.js
@@ -20,7 +20,10 @@ class Document extends React.Component {
           name={ this.props.document.user.name }
           timestamp={ this.props.document.createdAt }
         />
-        <div dangerouslySetInnerHTML={{ __html: this.props.document.html }} />
+        <div
+          className={ styles.document }
+          dangerouslySetInnerHTML={{ __html: this.props.document.html }}
+        />
       </div>
     );
   }
diff --git a/src/components/Document/Document.scss b/src/components/Document/Document.scss
index be5400ab..fa6dfcc5 100644
--- a/src/components/Document/Document.scss
+++ b/src/components/Document/Document.scss
@@ -2,3 +2,28 @@
   width: 100%;
   padding: 20px;
 }
+
+.document {
+  h1, h2, h3, h4, h5, h6 {
+    :global {
+      .anchor {
+        visibility: hidden;
+        background-image: url('../../assets/icons/anchor.svg');
+        background-repeat: no-repeat;
+        background-size: 100%;
+        background-position: 0 center;
+        margin-left: -26px;
+        width: 20px;
+        display: inline-block;
+      }
+    }
+
+    &:hover {
+      :global {
+        .anchor {
+          visibility: visible;
+        }
+      }
+    }
+  }
+}
\ No newline at end of file
diff --git a/src/scenes/DocumentScene/DocumentScene.js b/src/scenes/DocumentScene/DocumentScene.js
index 4c4a1658..1286ca23 100644
--- a/src/scenes/DocumentScene/DocumentScene.js
+++ b/src/scenes/DocumentScene/DocumentScene.js
@@ -17,6 +17,19 @@ class DocumentScene extends React.Component {
     this.props.fetchDocumentAsync(documentId);
   }
 
+  componentWillReceiveProps = (nextProps) => {
+    // Scroll to anchor after loading
+    const hash = this.props.location.hash;
+
+    if (nextProps.document && hash) {
+      const name = hash.split('#')[1];
+      setTimeout(() => {
+        const element = document.getElementsByName(name)[0];
+        if (element) element.scrollIntoView()
+      }, 0);
+    }
+  }
+
   render() {
     const document = this.props.document;
     let title;