Refactor source menu into proper control and fill it in intially.

Fixes #1084

data/core.yaml

@@ -182,3 +182,5 @@ en:
   zoom: 
     in: Zoom In
     out: Zoom Out
+  imagery:
+    provided_by: "Imagery provided by {source}"

js/id/renderer/background.js

@@ -156,7 +156,7 @@ iD.Background = function() {
         return background;
     };
 
-    function setPermalink(source) {
+    function setHash(source) {
         var tag = source.data.sourcetag;
         var q = iD.util.stringQs(location.hash.substring(1));
         if (tag) {
@@ -173,7 +173,7 @@ iD.Background = function() {
         source = _;
         cache = {};
         tile.scaleExtent((source.data && source.data.scaleExtent) || [1, 20]);
-        setPermalink(source);
+        setHash(source);
         return background;
     };
 

js/id/ui.js

@@ -100,6 +100,7 @@ iD.ui = function(context) {
         linkList.append('li')
             .attr('class', 'attribution')
             .attr('tabindex', -1)
+            .data([context.background().source()])
             .call(iD.ui.Attribution(context));
 
         linkList.append('li')

js/id/ui/attribution.js

@@ -1,10 +1,26 @@
 iD.ui.Attribution = function(context) {
-    return function(selection) {
-        selection.append('span')
-            .text('imagery');
+    return function attribution(selection) {
+        var d = selection.data()[0];
 
-        selection
+        var provided_by = selection
+            .html('')
             .append('span')
             .attr('class', 'provided-by');
+
+        if (!d) return;
+
+        var desc = t('imagery.provided_by', {
+            source: (d.data.sourcetag || d.data.name)
+        });
+
+        if (d.data.terms_url) {
+            provided_by.append('a')
+                .attr('href', (d.data.terms_url || ''))
+                .attr('target', '_blank')
+                .classed('disabled', !d.data.terms_url)
+                .text(desc);
+        } else {
+            provided_by.text(desc);
+        }
     };
 };

js/id/ui/background.js

@@ -110,21 +110,10 @@ iD.ui.Background = function(context) {
                     return d.data.name === context.background().source().data.name;
                 });
 
-            var provided_by = context.container()
-                .select('.attribution .provided-by')
-                .html('');
-
-            if (d.data.terms_url) {
-                provided_by.append('a')
-                    .attr('href', (d.data.terms_url || ''))
-                    .attr('target', '_blank')
-                    .classed('disabled', !d.data.terms_url)
-                    .text(' provided by ' + (d.data.sourcetag || d.data.name));
-            } else {
-                provided_by
-                    .text(' provided by ' + (d.data.sourcetag || d.data.name));
-            }
-
+            context.container()
+                .select('.attribution')
+                .data([d])
+                .call(iD.ui.Attribution(context));
         }
 
         function clickSetSource(d) {