/*
  ASCIIMathMLeditor.js
  ====================
  This file contains JavaScript functions that work with ASCIIMathML.js 
  to allow editing of ASCII math notation and conversion to a XHTML+MathML
  page. This is a convenient and inexpensive solution for authoring MathML.
  
  Version 1.4 July 14, 2004, (c) Peter Jipsen http://www.chapman.edu/~jipsen
  Latest version at http://www.chapman.edu/~jipsen/mathml/ASCIIMathMLeditor.js
  If you use it on a webpage, please send the URL to jipsen@chapman.edu
  
  This program is free software; you can redistribute it and/or modify
  it under the terms of the GNU General Public License as published by
  the Free Software Foundation; either version 2 of the License, or (at
  your option) any later version.
  
  This program is distributed in the hope that it will be useful, 
  but WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  General Public License (at http://www.gnu.org/copyleft/gpl.html) 
  for more details.
  */
  
  var AMkeyspressed = 20;
  
  function initEditor() {
    AMinitSymbols();
    var body = document.getElementsByTagName("body")[0];
    if (checkForMathML) {
      checkForMathML = false;
      var nd = AMisMathMLavailable();
      if (nd != null) body.insertBefore(nd,body.childNodes[0]);
    }
    AMdisplay(true);
  }
  
  function AMnode2string(inNode,indent) {
  // thanks to James Frazer for contributing an initial version of this function
     var i, str = "";
     if(inNode.nodeType == 1) {
         var name = inNode.nodeName.toLowerCase(); // (IE fix)
         str = "\r" + indent + "<" + name;
         for(i=0; i < inNode.attributes.length; i++)
             if (inNode.attributes[i].nodeValue!="italic" &&
                 inNode.attributes[i].nodeValue!="" &&  //stop junk attributes
                 inNode.attributes[i].nodeValue!="inherit" && // (mostly IE)
                 inNode.attributes[i].nodeValue!=undefined)
                 str += " "+inNode.attributes[i].nodeName+"="+
                       "\""+inNode.attributes[i].nodeValue+"\"";
         if (name == "math") 
             str += " xmlns=\"http://www.w3.org/1998/Math/MathML\"";
         str += ">";
         for(i=0; i<inNode.childNodes.length; i++)
             str += AMnode2string(inNode.childNodes[i], indent+"  ");
         if (name != "mo" && name != "mi" && name != "mn") str += "\r"+indent;
         str += "</" + name + ">";
     }
     else if(inNode.nodeType == 3) {
         var st = inNode.nodeValue;
         for (i=0; i<st.length; i++)
             if (st.charCodeAt(i)<32 || st.charCodeAt(i)>126)
                 str += "&#"+st.charCodeAt(i)+";";
             else if (st.charAt(i)=="<" && indent != "  ") str += "&lt;";
             else if (st.charAt(i)==">" && indent != "  ") str += "&gt;";
             else if (st.charAt(i)=="&" && indent != "  ") str += "&amp;";
             else str += st.charAt(i);
     }
     return str;
  } 
  
  function AMdisplay(now) {
    if (document.getElementById("inputText") != null) {
      if (AMkeyspressed == 20 || now) {
        var str = document.getElementById("inputText").value;
        var outnode = document.getElementById("outputNode");
        var newnode = AMcreateElementXHTML("div");
        newnode.setAttribute("id","outputNode");
        outnode.parentNode.replaceChild(newnode,outnode);
        outnode = document.getElementById("outputNode");
        var n = outnode.childNodes.length;
        for (var i = 0; i < n; i++)
          outnode.removeChild(outnode.firstChild);
        outnode.appendChild(document.createComment(str));
        AMprocessNode(outnode,true);
        AMkeyspressed = 0;
      } else AMkeyspressed++;
    }
  }
  
  function AMchangeColumns(n) {
    var node = document.getElementById("inputText");
    node.setAttribute("cols",n);
  }
  
  doubleblankmathdelimiter = true;
  
  function AMsetDoubleBlank() {
    doubleblankmathdelimiter = 
      document.getElementById("doubleblank").checked;
  }
  
  function AMviewMathML() {
    AMdisplay(true);
    var str = document.getElementById("inputText").value;
    var outnode = document.getElementById("outputNode");
    var outstr = AMnode2string(outnode,"").slice(22).slice(0,-6);
    outstr = '<?xml version="1.0"?>\r\<!-- Copy of ASCIIMathML input\r'+str+
  '-->\r<?xml-stylesheet type="text/xsl" href="http://www1.chapman.edu/~jipsen/mathml/pmathml.xsl"?>\r\
  <html xmlns="http://www.w3.org/1999/xhtml"\r\
    xmlns:mml="http://www.w3.org/1998/Math/MathML">\r\
  <head>\r<title>...</title>\r</head>\r<body>\r'+
  outstr+'<\/body>\r<\/html>\r';
    var newnode = AMcreateElementXHTML("textarea");
    newnode.setAttribute("id","outputNode");
    newnode.setAttribute("rows","30");
    var node = document.getElementById("inputText");
    newnode.setAttribute("cols",node.getAttribute("cols"));
    newnode.appendChild(document.createTextNode(outstr));
    outnode.parentNode.replaceChild(newnode,outnode);
  }