commonmark/lib/render/xml.js

a strongly specified, highly compatible variant of Markdown

"use strict";

var Renderer = require('./renderer');

var reXMLTag = /\<[^>]*\>/;

function toTagName(s) {
  return s.replace(/([a-z])([A-Z])/g, "$1_$2").toLowerCase();
}

function XmlRenderer(options) {
  options = options || {};

  this.disableTags = 0;
  this.lastOut = "\n";

  this.indentLevel = 0;
  this.indent = '  ';

  this.options = options;
}

function render(ast) {

  this.buffer = '';

  var attrs;
  var tagname;
  var walker = ast.walker();
  var event, node, entering;
  var container;
  var selfClosing;
  var nodetype;

  var options = this.options;

  if (options.time) { console.time("rendering"); }

  this.buffer += '<?xml version="1.0" encoding="UTF-8"?>\n';
  this.buffer += '<!DOCTYPE document SYSTEM "CommonMark.dtd">\n';

  while ((event = walker.next())) {
    entering = event.entering;
    node = event.node;
    nodetype = node.type;

    container = node.isContainer;

    selfClosing = nodetype === 'thematic_break'
      || nodetype === 'linebreak'
      || nodetype === 'softbreak';

    tagname = toTagName(nodetype);

    if (entering) {

        attrs = [];

        switch (nodetype) {
          case 'document':
            attrs.push(['xmlns', 'http://commonmark.org/xml/1.0']);
            break;
          case 'list':
            if (node.listType !== null) {
              attrs.push(['type', node.listType.toLowerCase()]);
            }
            if (node.listStart !== null) {
              attrs.push(['start', String(node.listStart)]);
            }
            if (node.listTight !== null) {
              attrs.push(['tight', (node.listTight ? 'true' : 'false')]);
            }
            var delim = node.listDelimiter;
            if (delim !== null) {
              var delimword = '';
              if (delim === '.') {
                delimword = 'period';
              } else {
                delimword = 'paren';
              }
              attrs.push(['delimiter', delimword]);
            }
            break;
          case 'code_block':
            if (node.info) {
              attrs.push(['info', node.info]);
            }
            break;
          case 'heading':
            attrs.push(['level', String(node.level)]);
            break;
          case 'link':
          case 'image':
            attrs.push(['destination', node.destination]);
            attrs.push(['title', node.title]);
            break;
          case 'custom_inline':
          case 'custom_block':
            attrs.push(['on_enter', node.onEnter]);
            attrs.push(['on_exit', node.onExit]);
            break;
          default:
            break;
        }
        if (options.sourcepos) {
          var pos = node.sourcepos;
          if (pos) {
            attrs.push(['sourcepos', String(pos[0][0]) + ':' +
              String(pos[0][1]) + '-' + String(pos[1][0]) + ':' +
              String(pos[1][1])]);
          }
        }

        this.cr();
        this.out(this.tag(tagname, attrs, selfClosing));
        if (container) {
          this.indentLevel += 1;
        } else if (!container && !selfClosing) {
          var lit = node.literal;
          if (lit) {
            this.out(this.esc(lit));
          }
          this.out(this.tag('/' + tagname));
        }
    } else {
      this.indentLevel -= 1;
      this.cr();
      this.out(this.tag('/' + tagname));
    }
  }
  if (options.time) { console.timeEnd("rendering"); }
  this.buffer += '\n';
  return this.buffer;
}

function out(s) {
  if(this.disableTags > 0) {
    this.buffer += s.replace(reXMLTag, '');
  }else{
    this.buffer += s;
  }
  this.lastOut = s;
}

function cr() {
  if(this.lastOut !== '\n') {
    this.buffer += '\n';
    this.lastOut = '\n';
    for(var i = this.indentLevel; i > 0; i--) {
      this.buffer += this.indent;
    }
  }
}

// Helper function to produce an XML tag.
function tag(name, attrs, selfclosing) {
  var result = '<' + name;
  if(attrs && attrs.length > 0) {
    var i = 0;
    var attrib;
    while ((attrib = attrs[i]) !== undefined) {
      result += ' ' + attrib[0] + '="' + this.esc(attrib[1]) + '"';
      i++;
    }
  }
  if(selfclosing) {
    result += ' /';
  }
  result += '>';
  return result;
}

// quick browser-compatible inheritance
XmlRenderer.prototype = Object.create(Renderer.prototype);

XmlRenderer.prototype.render = render;
XmlRenderer.prototype.out = out;
XmlRenderer.prototype.cr = cr;
XmlRenderer.prototype.tag = tag;
XmlRenderer.prototype.esc = require('../common').escapeXml;

module.exports = XmlRenderer;