1 files changed, 142 insertions, 0 deletions
diff --git a/website/showdown_toc.js b/website/showdown_toc.js
new file mode 100644
index 000000000..ba1f65c71
--- /dev/null
+++ b/website/showdown_toc.js
@@ -0,0 +1,142 @@
+// Extension loading compatible with AMD and CommonJs
+(function(extension) {
+  "use strict";
+
+  if (typeof showdown === "object") {
+    // global (browser or nodejs global)
+    showdown.extension("toc", extension());
+  } else if (typeof define === "function" && define.amd) {
+    // AMD
+    define("toc", extension());
+  } else if (typeof exports === "object") {
+    // Node, CommonJS-like
+    module.exports = extension();
+  } else {
+    // showdown was not found so we throw
+    throw Error("Could not find showdown library");
+  }
+})(function() {
+  function getHeaderEntries(sourceHtml) {
+    if (typeof window === "undefined") {
+      return getHeaderEntriesInNodeJs(sourceHtml);
+    } else {
+      return getHeaderEntriesInBrowser(sourceHtml);
+    }
+  }
+
+  function getHeaderEntriesInNodeJs(sourceHtml) {
+    var cheerio = require("cheerio");
+    var $ = cheerio.load(sourceHtml);
+    var headers = $("h1, h2, h3, h4, h5, h6");
+
+    var headerList = [];
+    for (var i = 0; i < headers.length; i++) {
+      var el = headers[i];
+      headerList.push(new TocEntry(el.name, $(el).text(), $(el).attr("id")));
+    }
+
+    return headerList;
+  }
+
+  function getHeaderEntriesInBrowser(sourceHtml) {
+    // Generate dummy element
+    var source = document.createElement("div");
+    source.innerHTML = sourceHtml;
+
+    // Find headers
+    var headers = source.querySelectorAll("h1, h2, h3, h4, h5, h6");
+    var headerList = [];
+    for (var i = 0; i < headers.length; i++) {
+      var el = headers[i];
+      headerList.push(new TocEntry(el.tagName, el.textContent, el.id));
+    }
+
+    return headerList;
+  }
+
+  function TocEntry(tagName, text, anchor) {
+    this.tagName = tagName;
+    this.text = text;
+    this.anchor = anchor;
+    this.children = [];
+  }
+
+  TocEntry.prototype.childrenToString = function() {
+    if (this.children.length === 0) {
+      return "";
+    }
+    var result = "<ul>\n";
+    for (var i = 0; i < this.children.length; i++) {
+      result += this.children[i].toString();
+    }
+    result += "</ul>\n";
+    return result;
+  };
+
+  TocEntry.prototype.toString = function() {
+    var result = "<li>";
+    if (this.text) {
+      result += '<a href="#' + this.anchor + '">' + this.text + "</a>";
+    }
+    result += this.childrenToString();
+    result += "</li>\n";
+    return result;
+  };
+
+  function sortHeader(tocEntries, level) {
+    level = level || 1;
+    var tagName = "H" + level,
+      result = [],
+      currentTocEntry;
+
+    function push(tocEntry) {
+      if (tocEntry !== undefined) {
+        if (tocEntry.children.length > 0) {
+          tocEntry.children = sortHeader(tocEntry.children, level + 1);
+        }
+        result.push(tocEntry);
+      }
+    }
+
+    for (var i = 0; i < tocEntries.length; i++) {
+      var tocEntry = tocEntries[i];
+      if (tocEntry.tagName.toUpperCase() !== tagName) {
+        if (currentTocEntry === undefined) {
+          currentTocEntry = new TocEntry();
+        }
+        currentTocEntry.children.push(tocEntry);
+      } else {
+        push(currentTocEntry);
+        currentTocEntry = tocEntry;
+      }
+    }
+
+    push(currentTocEntry);
+    return result;
+  }
+
+  return {
+    type: "output",
+    filter: function(sourceHtml) {
+      var headerList = getHeaderEntries(sourceHtml);
+
+      // No header found
+      if (headerList.length === 0) {
+        return sourceHtml;
+      }
+
+      // Sort header
+      headerList = sortHeader(headerList);
+
+      // Skip the title.
+      if (headerList.length == 1) {
+        headerList = headerList[0].children;
+      }
+
+      // Build result and replace all [toc]
+      var result =
+        '<div class="toc">\n<ul>\n' + headerList.join("") + "</ul>\n</div>\n";
+      return sourceHtml.replace(/\[toc\]/gi, result);
+    }
+  };
+});