From 5829af3d787ba109c25f45fa8af125bb0cac046e Mon Sep 17 00:00:00 2001
From: mbghsource <manikkandanb@gmail.com>
Date: Fri, 20 Jan 2012 15:48:23 -0500
Subject: [PATCH] Fix issue 264 - non-alpha chars in GViz annotation labels.

---
 dygraph.js                 | 15 ++++++++++++++-
 tests/annotation-gviz.html | 19 ++++++++++++-------
 2 files changed, 26 insertions(+), 8 deletions(-)

diff --git a/dygraph.js b/dygraph.js
index 66432f7..601967a 100644
--- a/dygraph.js
+++ b/dygraph.js
@@ -2774,6 +2774,19 @@ Dygraph.prototype.parseArray_ = function(data) {
  * @private
  */
 Dygraph.prototype.parseDataTable_ = function(data) {
+  var shortTextForAnnotationNum = function(num) {
+    // converts [0-9]+ [A-Z][a-z]*
+    // example: 0=A, 1=B, 25=Z, 26=Aa, 27=Ab
+    // and continues like.. Ba Bb .. Za .. Zz..Aaa...Zzz Aaaa Zzzz
+    var shortText = String.fromCharCode(65 /* A */ + num % 26);
+    num = Math.floor(num / 26);
+    while ( num > 0 ) {
+      shortText = String.fromCharCode(65 /* A */ + (num - 1) % 26 ) + shortText.toLowerCase();
+      num = Math.floor((num - 1) / 26);
+    }
+    return shortText;
+  }
+
   var cols = data.getNumberOfColumns();
   var rows = data.getNumberOfRows();
 
@@ -2855,7 +2868,7 @@ Dygraph.prototype.parseDataTable_ = function(data) {
           var ann = {};
           ann.series = data.getColumnLabel(col);
           ann.xval = row[0];
-          ann.shortText = String.fromCharCode(65 /* A */ + annotations.length);
+          ann.shortText = shortTextForAnnotationNum(annotations.length);
           ann.text = '';
           for (var k = 0; k < annotationCols[col].length; k++) {
             if (k) ann.text += "\n";
diff --git a/tests/annotation-gviz.html b/tests/annotation-gviz.html
index c043894..ec458b0 100644
--- a/tests/annotation-gviz.html
+++ b/tests/annotation-gviz.html
@@ -25,14 +25,20 @@
         data.addColumn('string', 'title2');
         data.addColumn('string', 'text2');
         data.addRows([
-          [new Date(2008, 1 ,1), 30000, undefined, undefined, 40645, undefined, undefined],
-          [new Date(2008, 1 ,2), 14045, undefined, undefined, 20374, undefined, undefined],
-          [new Date(2008, 1 ,3), 55022, undefined, undefined, 50766, undefined, undefined],
-          [new Date(2008, 1 ,4), 75284, undefined, undefined, 14334, 'Out of Stock','Ran out of stock on pens at 4pm'],
-          [new Date(2008, 1 ,5), 41476, 'Bought Pens','Bought 200k pens', 66467, undefined, undefined],
-          [new Date(2008, 1 ,6), 33322, undefined, undefined, 39463, undefined, undefined]
+          [new Date(2008, 11 ,1), 30000, undefined, undefined, 40645, undefined, undefined],
+          [new Date(2008, 11 ,2), 14045, undefined, undefined, 20374, undefined, undefined],
+          [new Date(2008, 11 ,3), 55022, undefined, undefined, 50766, undefined, undefined],
+          [new Date(2008, 11 ,4), 75284, undefined, undefined, 14334, 'Out of Stock','Ran out of stock on pens at 4pm'],
+          [new Date(2008, 11 ,5), 41476, 'Bought Pens','Bought 200k pens', 66467, undefined, undefined],
+          [new Date(2008, 11 ,6), 33322, undefined, undefined, 39463, undefined, undefined]
         ]);
 
+        for (var i = 1; i < 14; i++) {
+          data.addRows([
+            [new Date(2008, 11 , 6 + i), i * 1000, 'title1-' + i, 'text1 ' + (i * 1000 - i), (i * 2000 + i), 'title2-' + i, 'text2' + i * 1000],
+          ]);
+        }
+
         var chart = new google.visualization.AnnotatedTimeLine(document.getElementById('gviz_div'));
         chart.draw(data, {displayAnnotations: true});
 
@@ -50,4 +56,3 @@
     <div id='dg_div' style='width: 700px; height: 240px;'></div>
   </body>
 </html>
-
-- 
2.7.4