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- jsmath 3.3

    1: /*
    2:  *  autoload.js
    3:  *  
    4:  *  Part of the jsMath package for mathematics on the web.
    5:  *
    6:  *  This file is a plugin that checks if a page contains any math
    7:  *  that must be processed by jsMath, and only loads jsMath.js
    8:  *  when there is.
    9:  *  
   10:  *  You can control the items to look for via the variables
   11:  *  
   12:  *      jsMath.Autoload.findMathElements
   13:  *      jsMath.Autoload.findTeXstrings
   14:  *      jsMath.Autoload.findLaTeXstrings
   15:  *      jsMath.Autoload.findCustomStrings
   16:  *      jsMath.Autoload.findCustomSettings
   17:  *  
   18:  *  which control whether to look for SPAN and DIV elements of class
   19:  *  "math", TeX strings that will be converted by jsMath.ConvertTeX(), or
   20:  *  LaTeX strings that will be converted by jsMath.ConvertLaTeX().  By
   21:  *  default, the first is true and the second and third are false.  The
   22:  *  findCustomStrings can be used to specify your own delimiters for
   23:  *  in-line and display mathematics, e.g
   24:  *  
   25:  *      jsMath.Autoload.findCustomStrings = [
   26:  *         '[math],'[/math]',          // start and end in-line math
   27:  *         '[display]','[/display]'    // start and end display math
   28:  *      ];
   29:  *  
   30:  *  Finally, findCustomSettings can be set to an object reference whose
   31:  *  name:value pairs control the individual search settings for tex2math.  
   32:  *  (See the plugins/tex2math.js file for more details).
   33:  *  
   34:  *  If any math strings are found, jsMath.js will be loaded automatically, 
   35:  *  but not loaded otherwise.  If any of the last four are set and TeX math
   36:  *  strings are found, then plugins/tex2ath.js will be loaded
   37:  *  automatically.  jsMath.Autoload.needsJsMath will be set to true or
   38:  *  false depending on whether jsMath needed to be loaded.
   39:  *  
   40:  *  The value of jsMath.Autoload.element controls the element to be
   41:  *  searched by the autoload plug-in.  If unset, the complete document will
   42:  *  be searched.  If set to a string, the element with that name will be
   43:  *  searched.  If set to a DOM object, that object and its children will
   44:  *  be searched.
   45:  *  
   46:  *  Finally, there are two additional parameters that control files to
   47:  *  be loaded after jsMath.js, should it be needed.  These are
   48:  *  
   49:  *      jsMath.Autoload.loadFonts
   50:  *      jsMath.Autoload.loadFiles
   51:  *  
   52:  *  If jsMath.js is loaded, the fonts contained in the loadFonts array
   53:  *  will be loaded, and the JavaScript files listed in the loadFiles array
   54:  *  will be run.  Relative URL's are loaded based from the URL containing
   55:  *  jsMath.js.
   56:  *  
   57:  *  The autoload plugin can be loaded in the document HEAD or in the BODY. 
   58:  *  If it is loaded in the HEAD, you will need to call jsMath.Autoload.Check()
   59:  *  at the end of the BODY (say in the window.onload handler) in order to
   60:  *  get it to check the page for math that needs to be tagged, otherwise load
   61:  *  the file at the bottom of the BODY and it will run the check automatically.
   62:  *
   63:  *  You can call jsMath.Autoload.Run() after the check has been performed
   64:  *  in order to call the appropriate tex2math routines for the given Autoload
   65:  *  settings.  You can call jsMath.Autoload.Run() even when jsMath isn't loaded.
   66:  *  
   67:  *  ---------------------------------------------------------------------
   68:  *
   69:  *  Copyright 2004-2006 by Davide P. Cervone
   70:  * 
   71:  *  Licensed under the Apache License, Version 2.0 (the "License");
   72:  *  you may not use this file except in compliance with the License.
   73:  *  You may obtain a copy of the License at
   74:  * 
   75:  *      http://www.apache.org/licenses/LICENSE-2.0
   76:  * 
   77:  *  Unless required by applicable law or agreed to in writing, software
   78:  *  distributed under the License is distributed on an "AS IS" BASIS,
   79:  *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   80:  *  See the License for the specific language governing permissions and
   81:  *  limitations under the License.
   82:  */
   83: 
   84: /*************************************************************************/
   85: 
   86: /*
   87:  *  Make sure jsMath.Autoload is available
   88:  */
   89: if (!window.jsMath) {window.jsMath = {}}
   90: if (jsMath.Autoload == null) {jsMath.Autoload = {}}
   91: jsMath.Add = function (dst,src) {for (var id in src) {dst[id] = src[id]}},
   92: jsMath.document = document; // tex2math needs this
   93: 
   94: jsMath.Add(jsMath.Autoload,{
   95:   
   96:   Script: {
   97: 
   98:     iframe: null,  // the hidden iframe
   99: 
  100:     /*
  101:      *  Load an external JavaScript file asynchronously
  102:      */
  103:     Load: function (url) {
  104:       this.iframe = document.createElement('iframe');
  105:       this.iframe.style.visibility = 'hidden';
  106:       this.iframe.style.position = 'absolute';
  107:       this.iframe.style.width  = '0px';
  108:       this.iframe.style.height = '0px';
  109:       if (document.body.firstChild) {
  110:         document.body.insertBefore(this.iframe,document.body.firstChild);
  111:       } else {
  112:         document.body.appendChild(this.iframe);
  113:       }
  114:       this.url = url; setTimeout('jsMath.Autoload.Script.setURL()',100);
  115:     },
  116:     endLoad: function () {setTimeout('jsMath.Autoload.Script.AfterLoad()',1)},
  117: 
  118:     /*
  119:      *  Use location.replace() to avoid browsers placing the file in
  120:      *  the history (and messing up the BACK button action).  Not
  121:      *  completely effective in Firefox 1.0.x.  Safari won't handle
  122:      *  replace() if the document is local (not sure if that's really
  123:      *  the issue, but that's the only time I see it).
  124:      */
  125:     setURL: function () {
  126:       var url = jsMath.Autoload.root+"jsMath-autoload.html";
  127:       var doc = this.iframe.contentDocument;
  128:       if (!doc && this.iframe.contentWindow) {doc = this.iframe.contentWindow.document}
  129:       if (navigator.vendor == "Apple Computer, Inc." &&
  130:           document.location.protocol == 'file:') {doc = null}
  131:       if (doc) {doc.location.replace(url)} else {this.iframe.src = url}
  132:     },
  133: 
  134:     /*
  135:      *  Queue items that need to be postponed until jsMath has run
  136:      */
  137:     queue: [],
  138:     Push: function (name,data) {this.queue[this.queue.length] = [name,data]},
  139:     RunStack: function () {
  140:       if (this.tex2math) {jsMath.Autoload.Check2(); return}
  141:       for (var i = 0; i < this.queue.length; i++) {
  142:         var name = this.queue[i][0];
  143:         var data = this.queue[i][1];
  144:         if (data.length == 1) {jsMath[name](data[0])}
  145:           else {jsMath[name](data[0],data[1],data[2],data[3])}
  146:       }
  147:     },
  148:   
  149:     AfterLoad: function () {jsMath.Autoload.Script.RunStack()},
  150: 
  151:     /*
  152:      *  Look up the jsMath root directory, if it is not already supplied
  153:      */
  154:     Root: function () {
  155:       if (jsMath.Autoload.root) return;
  156:       var script = document.getElementsByTagName('script');
  157:       if (script) {
  158:         for (var i = 0; i < script.length; i++) {
  159:           var src = script[i].src;
  160:           if (src && src.match('(^|/)plugins/autoload.js$')) {
  161:             jsMath.Autoload.root = src.replace(/plugins\/autoload.js$/,'');
  162:             break;
  163:           }
  164:         }
  165:       }
  166:     }
  167: 
  168:   },
  169:   
  170:   /**************************************************************/
  171:   
  172:   /*
  173:    *  Load tex2math first (so we can call its search functions
  174:    *  to look to see if anything needs to be turned into math)
  175:    *  if it is needed, otherwise go on to the second check.
  176:    */
  177:   Check: function () {
  178:     if (this.checked) return; this.checked = 1;
  179:     if (this.findTeXstrings || this.findLaTeXstrings ||
  180:         this.findCustomStrings || this.findCustomSettings) {
  181:       this.Script.tex2math = 1;
  182:       this.Script.Load('plugins/tex2math.js');
  183:     } else {
  184:       if (!jsMath.tex2math) {jsMath.tex2math = {}}
  185:       this.Check2();
  186:     }
  187:   },
  188: 
  189:   /*
  190:    *  Once tex2math is loaded, use it to check for math that
  191:    *  needs to be tagged for jsMath, and load jsMath if it is needed
  192:    */
  193:   Check2: function () {
  194:     this.Script.tex2math = 0;
  195:     this.needsJsMath = 0; if (this.checkElement == null) {this.checkElement = null}
  196:     if (this.findMathElements) {
  197:       this.needsJsMath = this.areMathElements(this.checkElement);
  198:     }
  199:     jsMath.tex2math.callback = this.tex2mathCallback;
  200:     if (this.findTeXstrings && !this.needsJsMath) {
  201:       jsMath.tex2math.ConvertTeX(this.checkElement);
  202:     }
  203:     if (this.findLaTeXstrings && !this.needsJsMath) {
  204:       jsMath.tex2math.ConvertLaTeX(this.checkElement);
  205:     }
  206:     if (this.findCustomSettings && !this.needsJsMath) {
  207:       jsMath.tex2math.Convert(this.checkElement,this.findCustomSettings);
  208:     }
  209:     if (this.findCustomStrings && !this.needsJsMath) {
  210:       var s = this.findCustomStrings;
  211:       jsMath.tex2math.CustomSearch(s[0],s[1],s[2],s[3]);
  212:       jsMath.tex2math.ConvertCustom(this.checkElement);
  213:     }
  214:     jsMath.tex2math.callback = null;
  215: 
  216:     if (this.needsJsMath) {
  217:       this.LoadJsMath();
  218:     } else {
  219:       jsMath.Autoload.Script = null;
  220:       jsMath.Process = function () {};
  221:       jsMath.ProcessBeforeShowing = function () {};
  222:       jsMath.Synchronize = function () {};
  223:       jsMath.ConvertTeX = function () {};
  224:       jsMath.ConvertTeX2 = function () {};
  225:       jsMath.ConvertLaTeX = function () {};
  226:       jsMath.ConvertCustom = function () {};
  227:       jsMath.CustomSearch = function () {};
  228:       jsMath.Macro = function () {};
  229:       jsMath.Autoload.Run = function () {};
  230:     }
  231:   },
  232: 
  233:   /*
  234:    *  A callback used in the tex2math searches to signal that
  235:    *  some math has been found.
  236:    */
  237:   tex2mathCallback: function () {
  238:     jsMath.Autoload.needsJsMath = 1;
  239:     return false;
  240:   },
  241: 
  242:   /*
  243:    *  jsMath.Autoload.Run() can be called to perform the 
  244:    *  tex2math calls given by the Autoload parameters.
  245:    */
  246:   Run: function (data) {this.Script.Push('Autorun',[data])},
  247: 
  248:   Autorun: function () {
  249:     if (this.findTeXstrings) {jsMath.ConvertTeX(this.checkElement)}
  250:     if (this.findLaTeXstrings) {jsMath.ConvertLaTeX(this.checkElement)}
  251:     if (this.findCustomSettings) {
  252:       jsMath.Synchronize(function () {
  253:         jsMath.tex2math.Convert(jsMath.Autoload.checkElement,
  254:                                 jsMath.Autoload.findCustomSettings);
  255:       });
  256:     }
  257:     if (this.findCustomStrings) {
  258:       var s = this.findCustomStrings;
  259:       jsMath.CustomSearch(s[0],s[1],s[2],s[3]);
  260:       jsMath.ConvertCustom(this.checkElement);
  261:     }
  262:   },
  263: 
  264:   /*
  265:    *  Look to see if there are SPAN or DIV elements of class "math".
  266:    */
  267:   areMathElements: function (obj) {
  268:     if (!obj) {obj = document}
  269:     if (typeof(obj) == 'string') {obj = document.getElementById(obj)}
  270:     if (!obj.getElementsByTagName) {return false}
  271:     var math = obj.getElementsByTagName('div');
  272:     for (var k = 0; k < math.length; k++) 
  273:       {if (math[k].className.match(/(^| )math( |$)/)) {return true}}
  274:     math = obj.getElementsByTagName('span');
  275:     for (var k = 0; k < math.length; k++) 
  276:       {if (math[k].className.match(/(^| )math( |$)/)) {return true}}
  277:     return false;
  278:   },
  279: 
  280:   /*
  281:    *  When math tags are found, load the jsMath.js file,
  282:    *  and afterward, load any auxiliary files or fonts,
  283:    *  and then do any pending commands.
  284:    */
  285:   LoadJsMath: function () {
  286:     if (this.root) {
  287:       this.setMessage('Loading jsMath...');
  288:       this.Script.AfterLoad = this.afterLoad;
  289:       this.Script.Load('jsMath.js');
  290:     } else {
  291:       alert("Can't determine URL for jsMath.js");
  292:     }
  293:   },
  294:   afterLoad: function () {
  295:     if (jsMath.tex2math.window) {jsMath.tex2math.window.jsMath = jsMath}
  296:     //
  297:     //  Handle MSIE bug where jsMath.window both is and is not the actual window
  298:     //
  299:     if (jsMath.browser == 'MSIE') {window.onscroll = jsMath.window.onscroll};
  300:     var fonts = jsMath.Autoload.loadFonts;
  301:     if (fonts) {
  302:       if (typeof(fonts) != 'object') {fonts = [fonts]}
  303:       for (var i in fonts) {jsMath.Font.Load(fonts[i])}
  304:     }
  305:     var files = jsMath.Autoload.loadFiles;
  306:     if (files) {
  307:       if (typeof(files) != 'object') {files = [files]}
  308:       for (var i in files) {jsMath.Setup.Script(files[i])}
  309:     }
  310:     jsMath.Synchronize(function () {jsMath.Autoload.Script.RunStack()});
  311:     jsMath.Autoload.setMessage();
  312:   },
  313: 
  314:   /*
  315:    *  Display a message in a small box at the bottom of the screen
  316:    */
  317:   setMessage: function (message) {
  318:     if (message) {
  319:       this.div = document.createElement('div');
  320:       if (!document.body.hasChildNodes) {document.body.appendChild(this.div)}
  321:         else {document.body.insertBefore(this.div,document.body.firstChild)}
  322:       var style = {
  323:         position:'absolute', bottom:'1px', left:'2px',
  324:         backgroundColor:'#E6E6E6', border:'solid 1px #959595',
  325:         margin:'0px', padding:'1px 8px', zIndex:102,
  326:         color:'black', fontSize:'75%', width:'auto'
  327:       };
  328:       for (var id in style) {this.div.style[id] = style[id]}
  329:       this.div.appendChild(jsMath.document.createTextNode(message));
  330:     } else {
  331:       this.div.firstChild.nodeValue = "";
  332:       this.div.style.visibility = 'hidden';
  333:     }
  334:   }
  335:   
  336: });
  337: 
  338: /*
  339:  *  Queue these so we can do them after jsMath has been loaded
  340:  */
  341: jsMath.Add(jsMath,{
  342:   Process: function (data) {jsMath.Autoload.Script.Push('Process',[data])},
  343:   ProcessBeforeShowing: function (data) {jsMath.Autoload.Script.Push('ProcessBeforeShowing',[data])},
  344:   ConvertTeX: function (data) {jsMath.Autoload.Script.Push('ConvertTeX',[data])},
  345:   ConvertTeX2: function (data) {jsMath.Autoload.Script.Push('ConvertTeX2',[data])},
  346:   ConvertLaTeX: function (data) {jsMath.Autoload.Script.Push('ConvertLaTeX',[data])},
  347:   ConvertCustom: function (data) {jsMath.Autoload.Script.Push('ConvertCustom',[data])},
  348:   CustomSearch: function (d1,d2,d3,d4) {jsMath.Autoload.Script.Push('CustomSearch',[d1,d2,d3,d4])},
  349:   Synchronize: function (data) {jsMath.Autoload.Script.Push('Synchronize',[data])},
  350:   Macro: function (cs,def,params) {jsMath.Autoload.Script.Push('Macro',[cs,def,params])},
  351:   Autorun: function () {jsMath.Autoload.Autorun()}
  352: });
  353: 
  354: /*
  355:  *  Initialize
  356:  */
  357: 
  358: if (jsMath.Autoload.findMathElements == null) {jsMath.Autoload.findMathElements = 1}
  359: if (jsMath.Autoload.findTeXstrings == null)   {jsMath.Autoload.findTeXstrings = 0}
  360: if (jsMath.Autoload.findLaTeXstrings == null) {jsMath.Autoload.findLaTeXstrings = 0}
  361: 
  362: jsMath.Autoload.Script.Root();
  363: if (document.body) {jsMath.Autoload.Check()}