New partialRendering extension

js/extensionMgr.js

@@ -5,6 +5,7 @@ define([
     "classes/Extension",
     "settings",
     "text!html/settingsExtensionsAccordion.html",
+    "extensions/partialRendering",
     "extensions/userCustom",
     "extensions/googleAnalytics",
     "extensions/dialogAbout",

js/extensions/markdownExtra.js

@@ -61,6 +61,9 @@ define([
             editor.hooks.chain("onPreviewRefresh", prettyPrint);
         }
         Markdown.Extra.init(converter, options);
+        
+        // Store extensions list in converter for partialRendering
+        converter.extraExtensions = markdownExtra.config.extensions;
     };
 
     return markdownExtra;

js/extensions/partialRendering.js

@@ -0,0 +1,101 @@
+define([
+    "jquery",
+    "underscore",
+    "classes/Extension",
+    "text!html/partialRenderingSettingsBlock.html",
+], function($, _, Extension, partialRenderingSettingsBlockHTML) {
+
+    var partialRendering = new Extension("partialRendering", "Partial rendering", true);
+    partialRendering.settingsBlock = partialRenderingSettingsBlockHTML;
+
+    var converter = undefined;
+    var sectionList = [];
+    var convertedSectionsList = [];
+    var hasFootnotes = false;
+    function extractSections(text) {
+
+        text += "\n\n";
+
+        // Strip link definitions
+        var linkDefinition = "";
+        text = text.replace(/^[ ]{0,3}\[(.+)\]:[ \t]*\n?[ \t]*<?(\S+?)>?(?=\s|$)[ \t]*\n?[ \t]*((\n*)["(](.+?)[")][ \t]*)?(?:\n+)/gm, function(wholeMatch) {
+            linkDefinition += wholeMatch;
+            return "";
+        });
+
+        // And eventually footnotes...
+        hasFootnotes = false;
+        var doFootnotes = _.some(converter.extraExtensions, function(extension) {
+            return extension == "footnotes";
+        });
+        if(doFootnotes) {
+            text = text.replace(/\n[ ]{0,3}\[\^(.+?)\]\:[ \t]*\n?([\s\S]*?)\n{1,2}((?=\n[ ]{0,3}\S)|$)/g, function(wholeMatch) {
+                hasFootnotes = true;
+                linkDefinition += wholeMatch;
+                return "";
+            });
+        }
+
+        // Look for titles
+        var newSectionList = [];
+        var offset = 0;
+        text.replace(/^```.*\n[\s\S]*?\n```|(^.+[ \t]*\n=+[ \t]*\n+|^.+[ \t]*\n-+[ \t]*\n+|^\#{1,6}[ \t]*.+?[ \t]*\#*\n+)/gm, function(match, title, matchOffset) {
+            if(title) {
+                // We just found a title which means end of the previous section
+                if(matchOffset > offset) {
+                    newSectionList.push(text.substring(offset, matchOffset) + "\n" + linkDefinition);
+                    offset = matchOffset;
+                }
+            }
+            return "";
+        });
+        // Last section
+        newSectionList.push(text.substring(offset, text.length) + linkDefinition);
+
+        sectionList = newSectionList;
+    }
+
+    var isRendering = false;
+    function renderSections() {
+        // Renders sections
+        isRendering = true;
+        convertedSectionsList = _.map(sectionList, converter.makeHtml);
+        isRendering = false;
+
+        $("#wmd-preview").html(convertedSectionsList.join(""));
+
+        // Move footnotes in the footer...
+        if(hasFootnotes === true) {
+            // Recreate a footnote list
+            var footnoteElts = $("<ol>");
+            $("#wmd-preview > div.footnotes > ol > li").each(function(index) {
+                hasFootnotes = true;
+                var elt = $(this);
+                footnoteElts.append(elt);
+                // Restore footnotes numbers
+                var refId = "#fnref\\:" + elt.attr("id").substring(3);
+                $(refId).text(index + 1);
+            });
+            // Append the whole footnotes at the end of the document
+            $("#wmd-preview > div.footnotes").remove();
+            $("#wmd-preview").append($('<div class="footnotes">').append("<hr>").append(footnoteElts));
+        }
+
+    }
+
+    partialRendering.onEditorConfigure = function(editor) {
+        converter = editor.getConverter();
+        converter.hooks.chain("preConversion", function(text) {
+            if(isRendering === true) {
+                return text;
+            }
+            extractSections(text);
+            return "";
+        });
+        editor.hooks.chain("onPreviewRefresh", function() {
+            $("#wmd-preview").html(renderSections());
+        });
+    };
+
+    return partialRendering;
+});

js/html/partialRenderingSettingsBlock.html

@@ -0,0 +1,7 @@
+<p>Binds together editor and preview scrollbars.</p>
+<blockquote class="muted">
+	<b>NOTE:</b> The mapping between Markdown and HTML is based on the
+	position of the title elements (h1 h2 ...) in the page. Therefore if
+	your document does not contain any title the mapping will be linear and
+	consequently less accurate.
+</blockquote>