From ce16a3cc2efe42a85f0de6b416b320d220ef72fa Mon Sep 17 00:00:00 2001
From: benweet <benoit.schweblin@gmail.com>
Date: Wed, 5 Jun 2013 23:29:32 +0100
Subject: [PATCH] Fixed scroll link

---
 js/core.js                   | 35 +++++++++++++++++++++--------------
 js/extensions/scroll-link.js | 21 ++++++++++-----------
 2 files changed, 31 insertions(+), 25 deletions(-)

diff --git a/js/core.js b/js/core.js
index b4de48a2..9fd6cf97 100644
--- a/js/core.js
+++ b/js/core.js
@@ -207,24 +207,37 @@ define([
         fileDesc = fileDescParam;
         documentContent = undefined;
         var initDocumentContent = fileDesc.content;
-        $("#wmd-input").val(initDocumentContent);
+        var editorElt = $("#wmd-input");
+        editorElt.val(initDocumentContent);
         if(editor !== undefined) {
             // If the editor is already created
             undoManager.reinit(initDocumentContent, fileDesc.editorStart, fileDesc.editorEnd, fileDesc.editorScrollTop);
             editor.refreshPreview();
             return;
         }
-        // Store scrollTop on scroll event
-        $("#wmd-input").scroll(function() {
+        var previewContainerElt = $(".preview-container");
+        
+        // Store editor scrollTop on scroll event
+        editorElt.scroll(function() {
             if(documentContent !== undefined) {
                 fileDesc.editorScrollTop = $(this).scrollTop();
             }
         });
-        $(".preview-container").scroll(function() {
+        // Store editor selection on change
+        editorElt.bind("keyup mouseup", function() {
+            if(documentContent !== undefined) {
+                fileDesc.editorStart = this.selectionStart;
+                fileDesc.editorEnd = this.selectionEnd;
+            }
+        });
+        // Store preview scrollTop on scroll event
+        previewContainerElt.scroll(function() {
             if(documentContent !== undefined) {
                 fileDesc.previewScrollTop = $(this).scrollTop();
             }
         });
+        
+        // Create the converter and the editor 
         var converter = new Markdown.Converter();
         editor = new Markdown.Editor(converter);
         // Custom insert link dialog
@@ -243,7 +256,7 @@ define([
         });
 
         function checkDocumentChanges() {
-            var newDocumentContent = $("#wmd-input").val();
+            var newDocumentContent = editorElt.val();
             if(documentContent !== undefined && documentContent != newDocumentContent) {
                 fileDesc.content = newDocumentContent;
             }
@@ -256,8 +269,8 @@ define([
                 return function() {
                     if(documentContent === undefined) {
                         makePreview();
-                        $("#wmd-input").scrollTop(fileDesc.editorScrollTop);
-                        $(".preview-container").scrollTop(fileDesc.previewScrollTop);
+                        editorElt.scrollTop(fileDesc.editorScrollTop);
+                        previewContainerElt.scrollTop(fileDesc.previewScrollTop);
                     }
                     else {
                         debouncedMakePreview();
@@ -271,7 +284,7 @@ define([
                 return function() {
                     makePreview();
                     if(documentContent === undefined) {
-                        $(".preview-container").scrollTop(fileDesc.previewScrollTop);
+                        previewContainerElt.scrollTop(fileDesc.previewScrollTop);
                     }
                     checkDocumentChanges();
                 };
@@ -281,12 +294,6 @@ define([
         editor.hooks.chain("onPreviewRefresh", extensionMgr.onAsyncPreview);
         undoManager = editor.run(previewWrapper);
         undoManager.reinit(initDocumentContent, fileDesc.editorStart, fileDesc.editorEnd, fileDesc.editorScrollTop);
-        $("#wmd-input").bind("keydown click focus", function(event) {
-            if(documentContent !== undefined) {
-                fileDesc.editorStart = this.selectionStart;
-                fileDesc.editorEnd = this.selectionEnd;
-            }
-        });
 
         // Hide default buttons
         $(".wmd-button-row").addClass("btn-group").find("li:not(.wmd-spacer)").addClass("btn").css("left", 0).find("span").hide();
diff --git a/js/extensions/scroll-link.js b/js/extensions/scroll-link.js
index 3157cfb5..3ee042e9 100644
--- a/js/extensions/scroll-link.js
+++ b/js/extensions/scroll-link.js
@@ -23,6 +23,8 @@ define([
     function pxToFloat(px) {
         return parseFloat(px.substring(0, px.length - 2));
     }
+    var lastEditorScrollTop = undefined;
+    var lastPreviewScrollTop = undefined;
     var buildSections = _.debounce(function() {
 
         // Try to find Markdown sections by looking for titles
@@ -30,9 +32,9 @@ define([
         mdSectionList = [];
         // This textarea is used to measure sections height
         var textareaElt = $("#md-section-helper");
-        // It has to be the same width than wmd-input
+        // It has to be the same width as wmd-input
         textareaElt.width(editorElt.width());
-        // Consider wmd-input top padding
+        // Consider wmd-input top padding (will be used for 1st and last section) 
         var padding = pxToFloat(editorElt.css('padding-top'));
         var offset = 0, mdSectionOffset = 0;
         function addMdSection(sectionText) {
@@ -95,14 +97,11 @@ define([
         });
 
         // apply Scroll Link
-        lastEditorScrollTop = -10;
-        lastPreviewScrollTop = -10;
+        lastEditorScrollTop = editorElt.scrollTop();
+        lastPreviewScrollTop = previewScrollTop;
         runScrollLink();
     }, 500);
 
-    // -10 to be sure the gap is more than 9px
-    var lastEditorScrollTop = -10;
-    var lastPreviewScrollTop = -10;
     var isScrollEditor = false;
     var isScrollPreview = false;
     var runScrollLink = _.debounce(function() {
@@ -122,7 +121,6 @@ define([
             });
             if(srcSection === undefined) {
                 // Something wrong in the algorithm...
-                callback(-10);
                 return;
             }
             var posInSection = (srcScrollTop - srcSection.startOffset) / srcSection.height;
@@ -170,12 +168,12 @@ define([
     };
 
     scrollLink.onLayoutCreated = function() {
-        $(".preview-container").bind("keydown click focus mousewheel", function() {
+        $(".preview-container").bind("keyup mouseup mousewheel", function() {
             isScrollPreview = true;
             isScrollEditor = false;
             runScrollLink();
         });
-        $("#wmd-input").bind("keydown click focus mousewheel", function() {
+        $("#wmd-input").bind("keyup mouseup mousewheel", function() {
             isScrollEditor = true;
             isScrollPreview = false;
             runScrollLink();
@@ -186,7 +184,8 @@ define([
         editor.getConverter().hooks.chain("postConversion", function(text) {
             // To avoid losing scrolling position before elements are fully
             // loaded
-            $("#wmd-preview").height($("#wmd-preview").height());
+            var previewElt = $("#wmd-preview");
+            previewElt.height(previewElt.height());
             return text;
         });
     };