From c1cc2467e75c107c3e5091082d900eaf935d58d0 Mon Sep 17 00:00:00 2001
From: Kazuhiro MUSASHI <simoom634@yahoo.co.jp>
Date: Sun, 14 Apr 2019 00:00:44 +0800
Subject: [PATCH] Add a shorcode for TopoJSON support.

---
 layouts/partials/labs-header-content.html |  1 +
 layouts/shortcodes/leaflet-topojson.html  | 29 +++++++++++++++++++++++
 2 files changed, 30 insertions(+)
 create mode 100644 layouts/shortcodes/leaflet-topojson.html

diff --git a/layouts/partials/labs-header-content.html b/layouts/partials/labs-header-content.html
index ba6c6af..c72ff0f 100644
--- a/layouts/partials/labs-header-content.html
+++ b/layouts/partials/labs-header-content.html
@@ -51,6 +51,7 @@
   {{ if .Params.leaflet }}
   <!-- Make sure you put this AFTER Leaflet's CSS -->
   <script src="https://unpkg.com/leaflet@1.4.0/dist/leaflet.js" integrity="sha512-QVftwZFqvtRNi0ZyCtsznlKSWOStnDORoefr1enyq5mVL4tmKB3S/EnC3rRJcxCPavG10IcrVGSmPh6Qw5lwrg==" crossorigin=""></script>
+  <script src="https://cdnjs.cloudflare.com/ajax/libs/topojson/3.0.0/topojson.min.js"></script>
   {{ end }}
 
   <!-- OGP Settings
diff --git a/layouts/shortcodes/leaflet-topojson.html b/layouts/shortcodes/leaflet-topojson.html
new file mode 100644
index 0000000..0381274
--- /dev/null
+++ b/layouts/shortcodes/leaflet-topojson.html
@@ -0,0 +1,29 @@
+<script>
+  // Changing topojson to geojson
+  L.TopoJSON = L.GeoJSON.extend({
+    addData: function(jsonData) {
+      if (jsonData.type === "Topology") {
+        for (let key in jsonData.objects) {
+          if (jsonData.objects.hasOwnProperty(key)) {
+            let geojson = topojson.feature(jsonData, jsonData.objects[key]);
+            L.GeoJSON.prototype.addData.call(this, geojson);
+          }
+        }
+      } else {
+        L.GeoJSON.prototype.addData.call(this, jsonData);
+      }
+    }
+  });
+
+  const topoLayer = new L.TopoJSON();
+
+  fetch('{{ .Get "url" | plainify }}')
+    .then(response => {
+      return response.json();
+    })
+    .then(data => {
+      topoLayer.addData(data);
+      topoLayer.addTo(mymap);
+    });
+</script>
+