Implement a new system to handle "escape actions"

The new EscapeActions object decide what to do when the user press the
Escape key (such as closing a opened popup or inlined form).

This commit also re-introduced the sidebar current view as a sidebar
component local state.

client/lib/filter.js

@@ -4,6 +4,10 @@
 // goal is to filter complete documents by using the local filters for each
 // fields.
 
+var showFilterSidebar = function() {
+  Sidebar.setView('filter');
+};
+
 // Use a "set" filter for a field that is a set of documents uniquely
 // identified. For instance `{ labels: ['labelA', 'labelC', 'labelD'] }`.
 var SetFilter = function() {
@@ -18,29 +22,27 @@ _.extend(SetFilter.prototype, {
   },
 
   add: function(val) {
-    if (this.indexOfVal(val) === -1) {
+    if (this._indexOfVal(val) === -1) {
       this._selectedElements.push(val);
       this._dep.changed();
+      showFilterSidebar();
     }
   },
 
   remove: function(val) {
     var indexOfVal = this._indexOfVal(val);
-    if (this.indexOfVal(val) !== -1) {
+    if (this._indexOfVal(val) !== -1) {
       this._selectedElements.splice(indexOfVal, 1);
       this._dep.changed();
     }
   },
 
   toogle: function(val) {
-    var indexOfVal = this._indexOfVal(val);
-    if (indexOfVal === -1) {
-      this._selectedElements.push(val);
+    if (this._indexOfVal(val) === -1) {
+      this.add(val);
     } else {
-      this._selectedElements.splice(indexOfVal, 1);
+      this.remove(val);
     }
-
-    this._dep.changed();
   },
 
   reset: function() {

client/lib/keyboard.js

@@ -3,21 +3,6 @@
 // XXX There is no reason to define these shortcuts globally, they should be
 // attached to a template (most of them will go in the `board` template).
 
-// Pressing `Escape` should close the last opened “element” and only the last
-// one -- curently we handle popups and the card detailed view of the sidebar.
-Mousetrap.bind('esc', function() {
-  if (currentlyOpenedForm.get() !== null) {
-    currentlyOpenedForm.get().close();
-
-  } else if (Popup.isOpen()) {
-    Popup.back();
-
-  // XXX We should have a higher level API
-  } else if (Session.get('currentCard')) {
-    Utils.goBoardId(Session.get('currentBoard'));
-  }
-});
-
 Mousetrap.bind('w', function() {
   Sidebar.toogle();
 });
@@ -48,3 +33,46 @@ Mousetrap.bind(['down', 'up'], function(evt, key) {
     Utils.goCardId(nextCardId);
   }
 });
+
+// Pressing `Escape` should close the last opened “element” and only the last
+// one. Components can register themself using a priority number (smaller is
+// closed first), a condition, and an action.This is used by Popup or
+// inlinedForm for instance. When we press escape we execute the action which
+// condition is valid with the highest priority.
+EscapeActions = {
+  _actions: [],
+
+  register: function(priority, condition, action) {
+    // XXX Rewrite this with ES6: .push({ priority, condition, action })
+    this._actions.push({
+      priority: priority,
+      condition: condition,
+      action: action
+    });
+    // XXX Rewrite this with ES6: => function
+    this._actions = _.sortBy(this._actions, function(a) { return a.priority; });
+  },
+
+  executeLowest: function() {
+    var topActiveAction = _.find(this._actions, function(a) {
+      return !! a.condition();
+    });
+    return topActiveAction && topActiveAction.action();
+  },
+
+  executeLowerThan: function(maxPriority) {
+    maxPriority = maxPriority || Infinity;
+    var currentAction;
+    for (var i = 0; i < this._actions.length; i++) {
+      currentAction = this._actions[i];
+      if (currentAction.priority > maxPriority)
+        return;
+      if (!! currentAction.condition())
+        currentAction.action();
+    }
+  }
+};
+
+Mousetrap.bind('esc', function() {
+  EscapeActions.executeLowest();
+});

client/lib/popup.js

@@ -201,3 +201,7 @@ $(document).on('click', function(evt) {
     Popup.close();
   }
 });
+
+// Press escape to close the popup.
+var bindPopup = function(f) { return _.bind(f, Popup); };
+EscapeActions.register(20, bindPopup(Popup.isOpen), bindPopup(Popup.close));