From e6d4bd3e5f7c413a46ce6fc780e7087c1f13d7f6 Mon Sep 17 00:00:00 2001
From: George Cushen <gcushen@users.noreply.github.com>
Date: Wed, 20 Sep 2017 23:19:28 +0100
Subject: [PATCH] widgets: Add tag cloud

---
 exampleSite/content/home/tags.md        | 14 ++++++++++
 exampleSite/content/post/widgets.md     |  1 +
 layouts/partials/widgets/tag_cloud.html | 35 +++++++++++++++++++++++++
 3 files changed, 50 insertions(+)
 create mode 100644 exampleSite/content/home/tags.md
 create mode 100644 layouts/partials/widgets/tag_cloud.html

diff --git a/exampleSite/content/home/tags.md b/exampleSite/content/home/tags.md
new file mode 100644
index 00000000..cedab850
--- /dev/null
+++ b/exampleSite/content/home/tags.md
@@ -0,0 +1,14 @@
++++
+# Tag Cloud widget.
+
+date = 2017-09-20
+draft = false
+
+title = "Tags"
+subtitle = ""
+widget = "tag_cloud"
+
+# Order that this section will appear in.
+weight = 65
+
++++
diff --git a/exampleSite/content/post/widgets.md b/exampleSite/content/post/widgets.md
index 6f411da0..fbe9f6f7 100644
--- a/exampleSite/content/post/widgets.md
+++ b/exampleSite/content/post/widgets.md
@@ -19,6 +19,7 @@ Homepage widgets display as sections on the homepage. They can be enabled/disabl
 - Selected talks
 - Recent talks
 - Contact
+- Tag cloud
 - Custom widget (demonstrated with the *teaching* example)
 
 The example site that you copied to create your site uses all the different types of widget (except talks), so you can generally just delete the widgets you don't need and customize the parameters of the widgets you wish to keep.
diff --git a/layouts/partials/widgets/tag_cloud.html b/layouts/partials/widgets/tag_cloud.html
new file mode 100644
index 00000000..8b4965c0
--- /dev/null
+++ b/layouts/partials/widgets/tag_cloud.html
@@ -0,0 +1,35 @@
+{{ $ := .root }}
+{{ $page := .page }}
+
+<div class="row">
+  <div class="col-xs-12 col-md-4 section-heading">
+    <h1>{{ with $page.Title }}{{ . | markdownify }}{{ end }}</h1>
+    {{ with $page.Params.subtitle }}<p>{{ . | markdownify }}</p>{{ end }}
+  </div>
+  <div class="col-xs-12 col-md-8">
+    {{ with $page.Content }}<p>{{ . | markdownify }}</p>{{ end }}
+
+    {{ if not (eq (len $.Site.Taxonomies.tags) 0) }}
+      {{ $fontSmall := 0.8 }}
+      {{ $fontBig := 2.5 }}
+
+      {{ $fontDelta := sub $fontBig $fontSmall }}
+      {{ $min := len (index $.Site.Taxonomies.tags.ByCount.Reverse 0).Pages }}
+      {{ $max := add (len (index $.Site.Taxonomies.tags.ByCount 0).Pages) 1 }}
+      {{ $delta := sub $max $min }}
+      {{ $fontStep := div $fontDelta $delta }}
+
+      <div id="tag-cloud">
+        {{ range $name, $taxonomy := $.Site.Taxonomies.tags }}
+          {{ $tagCount := len $taxonomy.Pages }}
+          {{ $weight := div (sub (math.Log $tagCount) (math.Log $min)) (sub (math.Log $max) (math.Log $min)) }}
+          {{ $fontSize := add $fontSmall (mul (sub $fontBig $fontSmall) $weight) }}
+          {{ $urlPart1 := relLangURL "/tags/" }}
+          {{ $urlPart2 := urlize $name  }}
+          <a href="{{ delimit (slice $urlPart1 $urlPart2) "" }}" style="font-size:{{ $fontSize }}rem">{{ $name }}</a>
+        {{ end }}
+      </div>
+    {{ end }}
+
+  </div>
+</div>