From b557c65460cce44c89064b1e17f2ec992b1798f9 Mon Sep 17 00:00:00 2001
From: David Greenspan <dgreenspan@alum.mit.edu>
Date: Thu, 29 Aug 2013 19:52:03 -0700
Subject: [PATCH] start of Meteor UI Events

---
 packages/ui/domrange.js       | 65 +++++++++++++++++++++++++++++++++++
 packages/ui/domrange_tests.js | 52 ++++++++++++++++++++++++++++
 2 files changed, 117 insertions(+)

diff --git a/packages/ui/domrange.js b/packages/ui/domrange.js
index 22be68fff9..612c61b5a4 100644
--- a/packages/ui/domrange.js
+++ b/packages/ui/domrange.js
@@ -650,4 +650,69 @@ var moveWithOwnersIntoTbody = function (range) {
   return tbody;
 };
 
+///// EVENTS
+
+// XXX could write the form of arguments for this function
+// in several different ways, including simply as an event map.
+DomRange.prototype.on = function (events, selector, handler) {
+  var parentNode = this.parentNode();
+  if (! parentNode)
+    // if we're not in the DOM, silently fail.
+    return;
+
+  var eventTypes = [];
+  events.replace(/[^ /]+/g, function (e) {
+    eventTypes.push(e);
+  });
+
+  if (! handler && (typeof selector === 'function')) {
+    // omitted `selector`
+    handler = selector;
+    selector = null;
+  } else if (! selector) {
+    // take `""` to `null`
+    selector = null;
+  }
+
+  for (var i = 0, N = eventTypes.length; i < N; i++) {
+    var type = eventTypes[i];
+
+    var eventDict = parentNode.$_uievents;
+    if (! eventDict)
+      eventDict = (parentNode.$_uievents = {});
+
+    var info = eventDict[type];
+    if (! info) {
+      info = eventDict[type] = {};
+      info.handlers = [];
+    }
+    var handlerRecord = {
+      elem: parentNode,
+      type: type,
+      selector: selector,
+      $ui: this.component,
+      handler: handler
+    };
+    // It's important that lowLevelHandler be a different
+    // instance for each handlerRecord, because its identity
+    // is used to remove it.  Capture handlerRecord in a
+    // closure so that we have access to it, even when
+    // the var changes, and so we don't pull in the rest of
+    // the stack frame.
+    handlerRecord.lowLevelHandler = (function (h) {
+      return function (evt) {
+        if ((! selector) && evt.currentTarget !== evt.target)
+          // no selector means only fire on target
+          return;
+        return h.handler.call(h.$ui, evt);
+      };
+    })(handlerRecord);
+
+    info.handlers.push(handlerRecord);
+
+    $(parentNode).on(type, selector || '*',
+                     handlerRecord.lowLevelHandler);
+  }
+};
+
 UI.DomRange = DomRange;
\ No newline at end of file
diff --git a/packages/ui/domrange_tests.js b/packages/ui/domrange_tests.js
index a0a21f60c4..f8501008b9 100644
--- a/packages/ui/domrange_tests.js
+++ b/packages/ui/domrange_tests.js
@@ -1,5 +1,6 @@
 
 var DomRange = UI.DomRange;
+var parseHTML = UI.DomBackend.parseHTML;
 
 // fake component; DomRange host
 var Comp = function (which) {
@@ -16,6 +17,18 @@ var isEndMarker = function (n) {
   return (n.$ui && n === n.$ui.dom.end);
 };
 
+var inDocument = function (range, func) {
+  var onscreen = document.createElement("DIV");
+  onscreen.style.display = 'none';
+  document.body.appendChild(onscreen);
+  DomRange.insert(range.component, onscreen);
+  try {
+    func(range);
+  } finally {
+    document.body.removeChild(onscreen);
+  }
+};
+
 Tinytest.add("ui - DomRange - basic", function (test) {
   var r = new DomRange;
   r.which = 'R';
@@ -593,6 +606,45 @@ Tinytest.add("ui - DomRange - tables", function (test) {
   test.equal(tbody.childNodes[4].nodeName, 'TR');
 });
 
+Tinytest.add("ui - DomRange - basic events", function (test) {
+  // test.equal doesn't work on arrays of DOM nodes, so
+  // we need this.  It's `===` that descends recursively
+  // into any arrays.
+  var arrayEqual = function (a, b) {
+    test.equal(_.isArray(a), _.isArray(b));
+    if (_.isArray(a)) {
+      test.equal(a.length, b.length);
+      for (var i = 0; i < a.length; i++) {
+        arrayEqual(a[i], b[i]);
+      }
+    } else {
+      test.isTrue(a[i] === b[i]);
+    }
+  };
+
+  var htmlRange = function (html) {
+    var r = new DomRange;
+    _.each(parseHTML(html), function (node) {
+      r.add(node);
+    });
+    return r;
+  };
+
+  inDocument(
+    htmlRange("<span>Foo</span>"),
+    function (r) {
+      var buf = [];
+
+      r.on('click', 'span', function (evt) {
+        buf.push([evt.type, evt.target, evt.currentTarget]);
+      });
+
+      arrayEqual(buf, []);
+      var span = r.elements()[0];
+      span.click();
+      arrayEqual(buf, [['click', span, span]]);
+    });
+});
 
 // TO TEST STILL:
 // - external remove element