Makes the sidebar collapsible and stateful (#21808).

Patch inspired from user:jkraemer.

git-svn-id: https://svn.redmine.org/redmine/trunk@23218 e93f8b46-1217-0410-a6f0-8f06a7374b81

app/assets/javascripts/application.js

@@ -1261,6 +1261,77 @@ function inlineAutoComplete(element) {
     tribute.attach(element);
 }
 
+// collapsible sidebar jQuery plugin
+(function($) {
+  // main container this is applied to
+  var main;
+  // triggers show/hide
+  var button;
+  // the key to use in local storage
+  // this will later be expanded using the current controller and action to
+  // allow for different sidebar states for different pages
+  var localStorageKey = 'redmine-sidebar-state';
+  // true if local storage is available
+  var canUseLocalStorage = function(){
+    try {
+      if('localStorage' in window){
+        localStorage.setItem('redmine.test.storage', 'ok');
+        var item = localStorage.getItem('redmine.test.storage');
+        localStorage.removeItem('redmine.test.storage');
+        if(item === 'ok') return true;
+      }
+    } catch (err) {}
+    return false;
+  }();
+  // function to set current sidebar state
+  var setState = function(state){
+    if(canUseLocalStorage){
+      localStorage.setItem(localStorageKey, state);
+    }
+  };
+  var applyState = function(){
+    if(main.hasClass('collapsedsidebar')){
+      updateSVGIcon(main[0], 'chevrons-left')
+      setState('hidden');
+    } else {
+      updateSVGIcon(main[0], 'chevrons-right')
+      setState('visible');
+    }
+  };
+  var setupToggleButton = function(){
+    button = $('#sidebar-switch-button');
+    button.click(function(e){
+      main.addClass("animate");
+      main.toggleClass('collapsedsidebar');
+      applyState();
+      e.preventDefault();
+      return false;
+    });
+    applyState();
+  };
+  $.fn.collapsibleSidebar = function() {
+    main = this;
+    // determine previously stored sidebar state for this page
+    if(canUseLocalStorage) {
+      // determine current controller/action pair and use them as storage key
+      var bodyClass = $('body').attr('class');
+      if(bodyClass){
+        try {
+          localStorageKey += '-' + bodyClass.split(/\s+/).filter(function(s){
+            return s.match(/(action|controller)-.*/);
+          }).sort().join('-');
+        } catch(e) {
+          // in case of error (probably IE8), continue with the unmodified key
+        }
+      }
+      var storedState = localStorage.getItem(localStorageKey);
+      main.toggleClass('collapsedsidebar', storedState === 'hidden');
+    }
+    // draw the toggle button once the DOM is complete
+    $(document).ready(setupToggleButton);
+  };
+}(jQuery));
+
 $(document).ready(setupAjaxIndicator);
 $(document).ready(hideOnLoad);
 $(document).ready(addFormObserversForDoubleSubmit);