1 files changed, 347 insertions, 0 deletions
diff --git a/trunk/infrastructure/ace/www/skiplist.js b/trunk/infrastructure/ace/www/skiplist.js
new file mode 100644
index 0000000..e6c2e04
--- /dev/null
+++ b/trunk/infrastructure/ace/www/skiplist.js
@@ -0,0 +1,347 @@
+/**
+ * Copyright 2009 Google Inc.
+ * 
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * 
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS-IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+
+
+
+
+function newSkipList() {
+  var PROFILER = window.PROFILER;
+  if (!PROFILER) {
+    PROFILER = function() { return {start:noop, mark:noop, literal:noop, end:noop, cancel:noop}; };
+  }
+  function noop() {}
+
+  // if there are N elements in the skiplist, "start" is element -1 and "end" is element N
+  var start = {key:null, levels: 1, upPtrs:[null], downPtrs:[null], downSkips:[1], downSkipWidths:[0]};
+  var end = {key:null, levels: 1, upPtrs:[null], downPtrs:[null], downSkips:[null], downSkipWidths:[null]};
+  var numNodes = 0;
+  var totalWidth = 0;
+  var keyToNodeMap = {};
+  start.downPtrs[0] = end;
+  end.upPtrs[0] = start;
+  // a "point" object at location x allows modifications immediately after the first
+  // x elements of the skiplist, such as multiple inserts or deletes.
+  // After an insert or delete using point P, the point is still valid and points
+  // to the same index in the skiplist.  Other operations with other points invalidate
+  // this point.
+  function _getPoint(targetLoc) {
+    var numLevels = start.levels;
+    var lvl = numLevels-1;
+    var i = -1, ws = 0;
+    var nodes = new Array(numLevels);
+    var idxs = new Array(numLevels);
+    var widthSkips = new Array(numLevels);
+    nodes[lvl] = start;
+    idxs[lvl] = -1;
+    widthSkips[lvl] = 0;
+    while (lvl >= 0) {
+      var n = nodes[lvl];
+      while (n.downPtrs[lvl] &&
+	     (i + n.downSkips[lvl] < targetLoc)) {
+	i += n.downSkips[lvl];
+	ws += n.downSkipWidths[lvl];
+	n = n.downPtrs[lvl];
+      }
+      nodes[lvl] = n;
+      idxs[lvl] = i;
+      widthSkips[lvl] = ws;
+      lvl--;
+      if (lvl >= 0) {
+	nodes[lvl] = n;
+      }
+    }
+    return {nodes:nodes, idxs:idxs, loc:targetLoc, widthSkips:widthSkips, toString: function() {
+      return "getPoint("+targetLoc+")"; } };
+  }
+  function _getNodeAtOffset(targetOffset) {
+    var i = 0;
+    var n = start;
+    var lvl = start.levels-1;
+    while (lvl >= 0 && n.downPtrs[lvl]) {
+      while (n.downPtrs[lvl] && (i + n.downSkipWidths[lvl] <= targetOffset)) {
+	i += n.downSkipWidths[lvl];
+	n = n.downPtrs[lvl];
+      }
+      lvl--;
+    }
+    if (n === start) return (start.downPtrs[0] || null);
+    else if (n === end) return (targetOffset == totalWidth ? (end.upPtrs[0] || null) : null);
+    return n;
+  }
+  function _entryWidth(e) { return (e && e.width) || 0; }
+  function _insertKeyAtPoint(point, newKey, entry) {
+    var p = PROFILER("insertKey", false);
+    var newNode = {key:newKey, levels: 0, upPtrs:[], downPtrs:[], downSkips:[], downSkipWidths:[]};
+    p.mark("donealloc");
+    var pNodes = point.nodes;
+    var pIdxs = point.idxs;
+    var pLoc = point.loc;
+    var widthLoc = point.widthSkips[0] + point.nodes[0].downSkipWidths[0];
+    var newWidth = _entryWidth(entry);
+    p.mark("loop1");
+    while (newNode.levels == 0 || Math.random() < 0.01) {
+      var lvl = newNode.levels;
+      newNode.levels++;
+      if (lvl == pNodes.length) {
+	// assume we have just passed the end of point.nodes, and reached one level greater
+	// than the skiplist currently supports
+	pNodes[lvl] = start;
+	pIdxs[lvl] = -1;
+	start.levels++;
+	end.levels++;
+	start.downPtrs[lvl] = end;
+	end.upPtrs[lvl] = start;
+	start.downSkips[lvl] = numNodes+1;
+	start.downSkipWidths[lvl] = totalWidth;
+	point.widthSkips[lvl] = 0;
+      }
+      var me = newNode;
+      var up = pNodes[lvl];
+      var down = up.downPtrs[lvl];
+      var skip1 = pLoc - pIdxs[lvl];
+      var skip2 = up.downSkips[lvl] + 1 - skip1;
+      up.downSkips[lvl] = skip1;
+      up.downPtrs[lvl] = me;
+      me.downSkips[lvl] = skip2;
+      me.upPtrs[lvl] = up;
+      me.downPtrs[lvl] = down;
+      down.upPtrs[lvl] = me;
+      var widthSkip1 = widthLoc - point.widthSkips[lvl];
+      var widthSkip2 = up.downSkipWidths[lvl] + newWidth - widthSkip1;
+      up.downSkipWidths[lvl] = widthSkip1;
+      me.downSkipWidths[lvl] = widthSkip2;
+    }
+    p.mark("loop2");
+    p.literal(pNodes.length, "PNL");
+    for(var lvl=newNode.levels; lvl<pNodes.length; lvl++) {
+      var up = pNodes[lvl];
+      up.downSkips[lvl]++;
+      up.downSkipWidths[lvl] += newWidth;
+    }
+    p.mark("map");
+    keyToNodeMap['$KEY$'+newKey] = newNode;
+    numNodes++;
+    totalWidth += newWidth;
+    p.end();
+  }
+  function _getNodeAtPoint(point) {
+    return point.nodes[0].downPtrs[0];
+  }
+  function _incrementPoint(point) {
+    point.loc++;
+    for(var i=0;i<point.nodes.length;i++) {
+      if (point.idxs[i] + point.nodes[i].downSkips[i] < point.loc) {
+	point.idxs[i] += point.nodes[i].downSkips[i];
+	point.widthSkips[i] += point.nodes[i].downSkipWidths[i];
+	point.nodes[i] = point.nodes[i].downPtrs[i];
+      }
+    }
+  }
+  function _deleteKeyAtPoint(point) {
+    var elem = point.nodes[0].downPtrs[0];
+    var elemWidth = _entryWidth(elem.entry);
+    for(var i=0;i<point.nodes.length;i++) {
+      if (i < elem.levels) {
+	var up = elem.upPtrs[i];
+	var down = elem.downPtrs[i];
+	var totalSkip = up.downSkips[i] + elem.downSkips[i] - 1;
+	up.downPtrs[i] = down;
+	down.upPtrs[i] = up;
+	up.downSkips[i] = totalSkip;
+	var totalWidthSkip = up.downSkipWidths[i] + elem.downSkipWidths[i] - elemWidth;
+	up.downSkipWidths[i] = totalWidthSkip;
+      }
+      else {
+	var up = point.nodes[i];
+	var down = up.downPtrs[i];
+	up.downSkips[i]--;
+	up.downSkipWidths[i] -= elemWidth;
+      }
+    }
+    delete keyToNodeMap['$KEY$'+elem.key];
+    numNodes--;
+    totalWidth -= elemWidth;
+  }
+  function _propagateWidthChange(node) {
+    var oldWidth = node.downSkipWidths[0];
+    var newWidth = _entryWidth(node.entry);
+    var widthChange = newWidth - oldWidth;
+    var n = node;
+    var lvl = 0;
+    while (lvl < n.levels) {
+      n.downSkipWidths[lvl] += widthChange;
+      lvl++;
+      while (lvl >= n.levels && n.upPtrs[lvl-1]) {
+	n = n.upPtrs[lvl-1];
+      }
+    }
+    totalWidth += widthChange;
+  }
+  function _getNodeIndex(node, byWidth) {
+    var dist = (byWidth ? 0 : -1);
+    var n = node;
+    while (n !== start) {
+      var lvl = n.levels-1;
+      n = n.upPtrs[lvl];
+      if (byWidth) dist += n.downSkipWidths[lvl];
+      else dist += n.downSkips[lvl];
+    }
+    return dist;
+  }
+  /*function _debugToString() {
+    var array = [start];
+    while (array[array.length-1] !== end) {
+      array[array.length] = array[array.length-1].downPtrs[0];
+    }
+    function getIndex(node) {
+      if (!node) return null;
+      for(var i=0;i<array.length;i++) {
+	if (array[i] === node)
+	  return i-1;
+      }
+      return false;
+    }
+    var processedArray = map(array, function(node) {
+      var x = {key:node.key, levels: node.levels, downSkips: node.downSkips,
+	upPtrs: map(node.upPtrs, getIndex), downPtrs: map(node.downPtrs, getIndex),
+	downSkipWidths: node.downSkipWidths};
+      return x;
+    });
+    return map(processedArray, function (x) { return x.toSource(); }).join("\n");
+  }*/
+
+  function _getNodeByKey(key) {
+    return keyToNodeMap['$KEY$'+key];
+  }
+
+  // Returns index of first entry such that entryFunc(entry) is truthy,
+  // or length() if no such entry.  Assumes all falsy entries come before
+  // all truthy entries.
+  function _search(entryFunc) {
+    var low = start;
+    var lvl = start.levels-1;
+    var lowIndex = -1;
+    function f(node) {
+      if (node === start) return false;
+      else if (node === end) return true;
+      else return entryFunc(node.entry);
+    }
+    while (lvl >= 0) {
+      var nextLow = low.downPtrs[lvl];
+      while (!f(nextLow)) {
+	lowIndex += low.downSkips[lvl];
+	low = nextLow;
+	nextLow = low.downPtrs[lvl];
+      }
+      lvl--;
+    }
+    return lowIndex+1;
+  }
+
+/*
+The skip-list contains "entries", JavaScript objects that each must have a unique "key" property
+that is a string.
+*/
+  var self = {
+    length: function() { return numNodes; },
+    atIndex: function(i) {
+      if (i < 0) console.warn("atIndex("+i+")");
+      if (i >= numNodes) console.warn("atIndex("+i+">="+numNodes+")");
+      return _getNodeAtPoint(_getPoint(i)).entry;
+    },
+    // differs from Array.splice() in that new elements are in an array, not varargs
+    splice: function(start, deleteCount, newEntryArray) {
+      if (start < 0) console.warn("splice("+start+", ...)");
+      if (start + deleteCount > numNodes) {
+	console.warn("splice("+start+", "+deleteCount+", ...), N="+numNodes);
+	console.warn("%s %s %s", typeof start, typeof deleteCount, typeof numNodes);
+	console.trace();
+      }
+
+      if (! newEntryArray) newEntryArray = [];
+      var pt = _getPoint(start);
+      for(var i=0;i<deleteCount;i++) {
+	_deleteKeyAtPoint(pt);
+      }
+      for(var i=(newEntryArray.length-1);i>=0;i--) {
+	var entry = newEntryArray[i];
+	_insertKeyAtPoint(pt, entry.key, entry);
+	var node = _getNodeByKey(entry.key);
+	node.entry = entry;
+      }
+    },
+    next: function (entry) {
+      return _getNodeByKey(entry.key).downPtrs[0].entry || null;
+    },
+    prev: function (entry) {
+      return _getNodeByKey(entry.key).upPtrs[0].entry || null;
+    },
+    push: function(entry) {
+      self.splice(numNodes, 0, [entry]);
+    },
+    slice: function(start, end) {
+      // act like Array.slice()
+      if (start === undefined) start = 0;
+      else if (start < 0) start += numNodes;
+      if (end === undefined) end = numNodes;
+      else if (end < 0) end += numNodes;
+
+      if (start < 0) start = 0;
+      if (start > numNodes) start = numNodes;
+      if (end < 0) end = 0;
+      if (end > numNodes) end = numNodes;
+
+      dmesg(String([start,end,numNodes]));
+      if (end <= start) return [];
+      var n = self.atIndex(start);
+      var array = [n];
+      for(var i=1;i<(end-start);i++) {
+	n = self.next(n);
+	array.push(n);
+      }
+      return array;
+    },
+    atKey: function(key) { return _getNodeByKey(key).entry; },
+    indexOfKey: function(key) { return _getNodeIndex(_getNodeByKey(key)); },
+    indexOfEntry: function (entry) { return self.indexOfKey(entry.key); },
+    containsKey: function(key) { return !!(_getNodeByKey(key)); },
+    // gets the last entry starting at or before the offset
+    atOffset: function(offset) { return _getNodeAtOffset(offset).entry; },
+    keyAtOffset: function(offset) { return self.atOffset(offset).key; },
+    offsetOfKey: function(key) { return _getNodeIndex(_getNodeByKey(key), true); },
+    offsetOfEntry: function(entry) { return self.offsetOfKey(entry.key); },
+    setEntryWidth: function(entry, width) { entry.width = width; _propagateWidthChange(_getNodeByKey(entry.key)); },
+    totalWidth: function() { return totalWidth; },
+    offsetOfIndex: function(i) {
+      if (i < 0) return 0;
+      if (i >= numNodes) return totalWidth;
+      return self.offsetOfEntry(self.atIndex(i));
+    },
+    indexOfOffset: function(offset) {
+      if (offset <= 0) return 0;
+      if (offset >= totalWidth) return numNodes;
+      return self.indexOfEntry(self.atOffset(offset));
+    },
+    search: function(entryFunc) {
+      return _search(entryFunc);
+    },
+    //debugToString: _debugToString,
+    debugGetPoint: _getPoint,
+    debugDepth: function() { return start.levels; }
+  }
+  return self;
+}