Re-write

1 files changed, 78 insertions, 35 deletions

diff --git a/lib/dom-batch.js b/lib/dom-batch.js
index 903033e..62e1972 100644
--- a/lib/dom-batch.js
+++ b/lib/dom-batch.js
@@ -1,38 +1,81 @@
-(function() {
-  var domBatch = {};
-  var reads = [];
-  var writes = [];
-  var batch;
-
-  function call(fns) {
-    var fn;
-    while (fn = fns.shift()) fn();
-  }
+function DomBatch() {
+  this.reads = [];
+  this.writes = [];
 
-  domBatch.read = function(fn) {
-    batch = batch || setBatch();
-    reads.push(fn);
-  };
-
-  domBatch.write = function(fn) {
-    batch = batch || setBatch();
-    writes.push(fn);
-  };
-
-  function setBatch() {
-    return setTimeout(function() {
-      call(reads);
-      call(writes);
-      batch = null;
-    }, 0);
-  }
+  this.mode = null;
+  this.pending = false;
+
+  // Bind context
+  this.run = this.run.bind(this);
+  this.frame = this.frame.bind(this);
+}
+
+DomBatch.prototype.read = function(fn) {
+  this.reads.push(fn);
+  this.request('read');
+};
+
+DomBatch.prototype.write = function(fn) {
+  this.writes.push(fn);
+  this.request('write');
+};
+
+DomBatch.prototype.request = function(type) {
+
+  // If we are currently writing, we don't
+  // need to scedule a new frame as this
+  // job will be emptied from the write queue
+  if (this.mode === 'writing' && type === 'write') return;
+
+  // If we are reading we don't need to schedule
+  // a new frame as this read will be emptied
+  // in the currently active read queue
+  if (this.mode === 'reading' && type === 'read') return;
+
+  // If we are reading we don't need to schedule
+  // a new frame and this write job will be run
+  // after the read queue has been emptied in the
+  // currently active frame.
+  if (this.mode === 'reading' && type === 'write') return;
 
-  // Expose the library
-  if (typeof exports === "object") {
-    module.exports = domBatch;
-  } else if (typeof define === "function" && define.amd) {
-    define(domBatch);
-  } else {
-    window['domBatch'] = domBatch;
+  // If there is already a frame
+  // scheduled, don't schedule another one
+  if (this.pending) return;
+
+  // Schedule frame
+  requestAnimationFrame(this.frame);
+
+  // Set flag to indicate
+  // a frame has been scheduled
+  this.pending = true;
+};
+
+DomBatch.prototype.run = function(q) {
+  while (q.length) {
+    q.shift().call(this);
   }
-}());
\ No newline at end of file
+};
+
+// How can a request be made if the
+// emptying of the queue is in progress?????
+
+DomBatch.prototype.frame = function() {
+
+  // Set the pending flag to
+  // false so that any new requests
+  // that come in will schedule a new frame
+  this.pending = false;
+
+  // Set the mode to 'reading' so
+  // that we know we can add more
+  // reads to the queue instead of
+  // scheduling a new frame.
+  this.mode = 'reading';
+  this.run(this.reads);
+
+  // Set
+  this.mode = 'writing';
+  this.run(this.writes);
+
+  this.mode = null;
+};