Fixed infinite loop on invalid modal request, and implemented modal contents caching

static/js/map.js

@@ -15,6 +15,7 @@ BusMap.Map = function(opts) {
     this.opts = opts;
     var stops = {};
     var routes = {};
+    var modal_cache = {};
     var that = this;
     window._busmap = this;
 
@@ -399,10 +400,18 @@ BusMap.Map = function(opts) {
             query: "modal",
             modal_name: name,
         };
-        $.get("ajax", params).done(function(contents) {
-            modal.append(contents);
-        });
-        setUrlFromView();
+        if (modal_cache[name]) {
+            modal.append(modal_cache[name]);
+            setUrlFromView();
+        } else {
+            $.get("ajax", params).done(function(contents) {
+                modal_cache[name] = contents;
+                modal.append(contents);
+                setUrlFromView();
+            }).fail(function() {
+                modal.append("Please refresh the page and try again.");
+            });
+        }
     }
 
     // Scaling: update what is displayed based on zoom level
@@ -428,7 +437,7 @@ BusMap.Map = function(opts) {
             return;
         }
         var hash = window.location.hash.substring(1);
-        if (hash == "") return false;
+        if (hash == "") return;
         var parts = hash.split(";");
         // First part: view string (lat,lon,zoom; vehicle; or stop)
         applyViewString(parts[0]);