X-Git-Url: https://git.openstreetmap.org./rails.git/blobdiff_plain/1082d3a6535c5c2a777ae64a3067e9f8657bd32c..69fdcfd163835c57e56d086486404deb3dc8b928:/app/assets/javascripts/router.js

diff --git a/app/assets/javascripts/router.js b/app/assets/javascripts/router.js
index fbad1e28c..cadb6b628 100644
--- a/app/assets/javascripts/router.js
+++ b/app/assets/javascripts/router.js
@@ -1,3 +1,50 @@
+/*
+  OSM.Router implements pushState-based navigation for the main page and
+  other pages that use a sidebar+map based layout (export, search results,
+  history, and browse pages).
+
+  For browsers without pushState, it falls back to full page loads, which all
+  of the above pages support.
+
+  The router is initialized with a set of routes: a mapping of URL path templates
+  to route controller objects. Path templates can contain placeholders
+  (`/note/:id`) and optional segments (`/:type/:id(/history)`).
+
+  Route controller objects can define four methods that are called at defined
+  times during routing:
+
+     * The `load` method is called by the router when a path which matches the
+       route's path template is loaded via a normal full page load. It is passed
+       as arguments the URL path plus any matching arguments for placeholders
+       in the path template.
+
+     * The `pushstate` method is called when a page which matches the route's path
+       template is loaded via pushState. It is passed the same arguments as `load`.
+
+     * The `popstate` method is called when returning to a previously
+       pushState-loaded page via popstate (i.e. browser back/forward buttons).
+
+     * The `unload` method is called on the exiting route controller when navigating
+       via pushState or popstate to another route.
+
+   Note that while `load` is not called by the router for pushState-based loads,
+   it's frequently useful for route controllers to call it manually inside their
+   definition of the `pushstate` and `popstate` methods.
+
+   An instance of OSM.Router is assigned to `OSM.router`. To navigate to a new page
+   via pushState (with automatic full-page load fallback), call `OSM.router.route`:
+
+       OSM.router.route('/way/1234');
+
+   If `route` is passed a path that matches one of the path templates, it performs
+   the appropriate actions and returns true. Otherwise it returns false.
+
+   OSM.Router also handles updating the hash portion of the URL containing transient
+   map state such as the position and zoom level. Some route controllers may wish to
+   temporarily suppress updating the hash (for example, to omit the hash on pages
+   such as `/way/1234` unless the map is moved). This can be done by calling
+   `OSM.router.moveListenerOff` and `OSM.router.moveListenerOn`.
+ */
 OSM.Router = function(map, rts) {
   var escapeRegExp  = /[\-{}\[\]+?.,\\\^$|#\s]/g;
   var optionalParam = /\((.*?)\)/g;
@@ -28,7 +75,7 @@ OSM.Router = function(map, rts) {
         });
       }
 
-      (controller[action] || $.noop).apply(controller, params);
+      return (controller[action] || $.noop).apply(controller, params);
     };
 
     return route;
@@ -44,41 +91,13 @@ OSM.Router = function(map, rts) {
     }
   };
 
-  var currentPath = window.location.pathname + window.location.search,
+  var currentPath = window.location.pathname.replace(/(.)\/$/, '$1') + window.location.search,
     currentRoute = routes.recognize(currentPath),
     currentHash = location.hash || OSM.formatHash(map);
 
-  currentRoute.run('load', currentPath);
-
-  var stateChange;
-
-  map.on('moveend baselayerchange overlaylayerchange', function() {
-    var hash = OSM.formatHash(map);
-    if (hash === currentHash) return;
-    currentHash = hash;
-    stateChange(OSM.parseHash(hash), hash);
-  });
-
-  $(window).on('hashchange', function() {
-    var hash = location.hash;
-    if (hash === currentHash) return;
-    currentHash = hash;
-    var state = OSM.parseHash(hash);
-    if (!state) return;
-    map.setView(state.center, state.zoom);
-    map.updateLayers(state.layers);
-    stateChange(state, hash);
-  });
+  var router = {};
 
   if (window.history && window.history.pushState) {
-    stateChange = function(state, hash) {
-      window.history.replaceState(state, document.title, hash);
-    };
-
-    // Set a non-null initial state, so that the e.originalEvent.state
-    // check below works correctly when going back to the initial page.
-    stateChange(OSM.parseHash(currentHash), currentPath + currentHash);
-
     $(window).on('popstate', function(e) {
       if (!e.originalEvent.state) return; // Is it a real popstate event or just a hash change?
       var path = window.location.pathname + window.location.search;
@@ -88,11 +107,13 @@ OSM.Router = function(map, rts) {
       currentRoute = routes.recognize(currentPath);
       currentRoute.run('popstate', currentPath);
       var state = e.originalEvent.state;
-      map.setView(state.center, state.zoom, {animate: false});
-      map.updateLayers(state.layers);
+      if (state.center) {
+        map.setView(state.center, state.zoom, {animate: false});
+        map.updateLayers(state.layers);
+      }
     });
 
-    return function (url) {
+    router.route = function (url) {
       var path = url.replace(/#.*/, ''),
         route = routes.recognize(path);
       if (!route) return false;
@@ -102,14 +123,58 @@ OSM.Router = function(map, rts) {
       currentRoute = route;
       currentRoute.run('pushstate', currentPath);
       return true;
-    }
-  } else {
-    stateChange = function(state, hash) {
-      window.location.replace(hash);
     };
 
-    return function (url) {
+    router.stateChange = function(state) {
+      if (state.center) {
+        window.history.replaceState(state, document.title, OSM.formatHash(state));
+      } else {
+        window.history.replaceState(state, document.title, window.location);
+      }
+    };
+  } else {
+    router.route = function (url) {
       window.location.assign(url);
-    }
+    };
+
+    router.stateChange = function(state) {
+      if (state.center) window.location.replace(OSM.formatHash(state));
+    };
   }
+
+  router.updateHash = function() {
+    var hash = OSM.formatHash(map);
+    if (hash === currentHash) return;
+    currentHash = hash;
+    router.stateChange(OSM.parseHash(hash));
+  };
+
+  router.hashUpdated = function() {
+    var hash = location.hash;
+    if (hash === currentHash) return;
+    currentHash = hash;
+    var state = OSM.parseHash(hash);
+    if (!state) return;
+    map.setView(state.center, state.zoom);
+    map.updateLayers(state.layers);
+    router.stateChange(state, hash);
+  };
+
+  router.moveListenerOn = function() {
+    map.on('moveend', router.updateHash);
+  };
+
+  router.moveListenerOff = function() {
+    map.off('moveend', router.updateHash);
+  };
+
+  router.load = function() {
+    var loadState = currentRoute.run('load', currentPath);
+    router.stateChange(loadState || {});
+  };
+
+  map.on('moveend baselayerchange overlaylayerchange', router.updateHash);
+  $(window).on('hashchange', router.hashUpdated);
+
+  return router;
 };