From 7f4673ae4be7ddca1fd698c699d92a1f668edbdc Mon Sep 17 00:00:00 2001
From: David Kaltschmidt <david.kaltschmidt@gmail.com>
Date: Wed, 16 Sep 2015 12:53:33 +0200
Subject: [PATCH] Show message in UI when topology too big to render

---
 client/app/scripts/charts/nodes-chart.js | 58 ++++++++++++------------
 client/app/scripts/components/nodes.js   | 26 +++++------
 client/app/styles/main.less              | 25 +++++++++-
 3 files changed, 65 insertions(+), 44 deletions(-)

diff --git a/client/app/scripts/charts/nodes-chart.js b/client/app/scripts/charts/nodes-chart.js
index 9db84f0cb..b6101992d 100644
--- a/client/app/scripts/charts/nodes-chart.js
+++ b/client/app/scripts/charts/nodes-chart.js
@@ -48,7 +48,7 @@ const NodesChart = React.createClass({
       .scaleExtent([0.1, 2])
       .on('zoom', this.zoomed);
 
-    d3.select('.nodes-chart')
+    d3.select('.canvas')
       .on('click', this.handleBackgroundClick)
       .call(this.zoom);
   },
@@ -81,7 +81,7 @@ const NodesChart = React.createClass({
   componentWillUnmount: function() {
     // undoing .call(zoom)
 
-    d3.select('.nodes-chart')
+    d3.select('.canvas')
       .on('click', null)
       .on('mousedown.zoom', null)
       .on('onwheel', null)
@@ -161,35 +161,34 @@ const NodesChart = React.createClass({
       translate = shiftTranslate;
       wasShifted = true;
     }
-
-    if (this.state.maxNodesExceeded) {
-      return (
-        <div className="nodes-chart-error">
-          <span className="fa fa-ban" />
-        </div>
-      );
-    }
+    const errorClassNames = this.state.maxNodesExceeded ? 'nodes-chart-error' : 'nodes-chart-error hide';
 
     return (
-      <svg width="100%" height="100%" className="nodes-chart">
-        <Spring endValue={{val: translate, config: [80, 20]}}>
-          {function(interpolated) {
-            let interpolatedTranslate = wasShifted ? interpolated.val : panTranslate;
-            const transform = 'translate(' + interpolatedTranslate + ')' +
-              ' scale(' + scale + ')';
-            return (
-              <g className="canvas" transform={transform}>
-                <g className="edges">
-                  {edgeElements}
+      <div className="nodes-chart">
+        <div className={errorClassNames}>
+          <span className="nodes-chart-error-icon fa fa-ban" />
+          <div>Too many nodes to show in the browser.<br />Please select a different topology.</div>
+        </div>
+        <svg width="100%" height="100%">
+          <Spring endValue={{val: translate, config: [80, 20]}}>
+            {function(interpolated) {
+              let interpolatedTranslate = wasShifted ? interpolated.val : panTranslate;
+              const transform = 'translate(' + interpolatedTranslate + ')' +
+                ' scale(' + scale + ')';
+              return (
+                <g className="canvas" transform={transform}>
+                  <g className="edges">
+                    {edgeElements}
+                  </g>
+                  <g className="nodes">
+                    {nodeElements}
+                  </g>
                 </g>
-                <g className="nodes">
-                  {nodeElements}
-                </g>
-              </g>
-            );
-          }}
-        </Spring>
-      </svg>
+              );
+            }}
+          </Spring>
+        </svg>
+      </div>
     );
   },
 
@@ -413,7 +412,8 @@ const NodesChart = React.createClass({
       nodes: nodes,
       edges: edges,
       nodeScale: nodeScale,
-      scale: zoomScale
+      scale: zoomScale,
+      maxNodesExceeded: false
     };
   },
 
diff --git a/client/app/scripts/components/nodes.js b/client/app/scripts/components/nodes.js
index c2e088c19..c6737d4e5 100644
--- a/client/app/scripts/components/nodes.js
+++ b/client/app/scripts/components/nodes.js
@@ -29,20 +29,18 @@ const Nodes = React.createClass({
 
   render: function() {
     return (
-      <div id="nodes">
-        <NodesChart
-          highlightedEdgeIds={this.props.highlightedEdgeIds}
-          highlightedNodeIds={this.props.highlightedNodeIds}
-          selectedNodeId={this.props.selectedNodeId}
-          nodes={this.props.nodes}
-          onNodeClick={this.onNodeClick}
-          width={this.state.width}
-          height={this.state.height}
-          topologyId={this.props.topologyId}
-          detailsWidth={this.props.detailsWidth}
-          topMargin={this.props.topMargin}
-        />
-      </div>
+      <NodesChart
+        highlightedEdgeIds={this.props.highlightedEdgeIds}
+        highlightedNodeIds={this.props.highlightedNodeIds}
+        selectedNodeId={this.props.selectedNodeId}
+        nodes={this.props.nodes}
+        onNodeClick={this.onNodeClick}
+        width={this.state.width}
+        height={this.state.height}
+        topologyId={this.props.topologyId}
+        detailsWidth={this.props.detailsWidth}
+        topMargin={this.props.topMargin}
+      />
     );
   },
 
diff --git a/client/app/styles/main.less b/client/app/styles/main.less
index f7d843f60..2970640cb 100644
--- a/client/app/styles/main.less
+++ b/client/app/styles/main.less
@@ -35,6 +35,14 @@
   text-overflow: ellipsis;
 }
 
+.hideable {
+  transition: opacity .5s ease-in-out;
+}
+
+.hide {
+  opacity: 0;
+}
+
 * {
   box-sizing: border-box;
   -webkit-tap-highlight-color: rgba(0, 0, 0, 0);
@@ -174,7 +182,22 @@ h2 {
   }
 }
 
-#nodes {
+.nodes-chart {
+
+  &-error {
+    .hideable;
+    position: absolute;
+    left: 50%;
+    top: 50%;
+    transform: translate(-50%, -50%);
+    text-align: center;
+    color: @text-secondary-color;
+
+    &-icon {
+      opacity: 0.25;
+      font-size: 320px;
+    }
+  }
 
   svg {
     position: absolute;