matitaB/matita/matitaweb.js

   1 var locked;
   2 var unlocked;
   3 var workarea;
   4 var scriptcell;
   5 var goalcell;
   6 var goals;
   7 var goalview;
   8 var filename;
   9 var logarea;
  10 var advanceButton;
  11 var retractButton;
  12 var cursorButton;
  13 var bottomButton;
  14 var dialogBox;
  15 var dialogTitle;
  16 var dialogContent;
  17 var metasenv = "";
  18 var lockedbackup = "";
  19 var matita;
  20
  21 function text_of_html(h)
  22 {
  23   if(document.all) {
  24      return h.innerText;
  25   } else {
  26      return h.textContent;
  27   }
  28 }
  29
  30 function unescape_html(s)
  31 {
  32   u = document.getElementById("unescape");
  33   u.innerHTML = s;
  34   return text_of_html(u)
  35 }
  36
  37 function filterByClass (elements,cname){
  38   var itemsfound = new Array;
  39   for(var i=0;i<elements.length;i++){
  40     if(elements[i].className == cname){
  41       itemsfound.push(elements[i]);
  42     }
  43   }
  44   return itemsfound;
  45 }
  46
  47 function initialize()
  48 {
  49   if (readCookie("session") == null) {
  50     window.location = "/login.html"
  51   } else {
  52     body = document.body;
  53     titlebar = document.getElementById("titlebar");
  54     matitaTitle = document.getElementById("matitaTitle");
  55     apparea = document.getElementById("matitaapparea");
  56     locked = document.getElementById("locked");
  57     unlocked = document.getElementById("unlocked");
  58     toparea = document.getElementById("toparea");
  59     workarea = document.getElementById("workarea");
  60     scriptcell = document.getElementById("scriptcell");
  61     sidearea = document.getElementById("sidearea");
  62     disambcell = document.getElementById("disambcell");
  63     goalcell = document.getElementById("goalcell");
  64     goals = document.getElementById("goals");
  65     goalview = document.getElementById("goalview");
  66     filename = document.getElementById("filename");
  67     logarea = document.getElementById("logarea");
  68     advanceButton = document.getElementById("advance");
  69     retractButton = document.getElementById("retract");
  70     cursorButton = document.getElementById("cursor");
  71     bottomButton = document.getElementById("bottom");
  72     dialogBox = document.getElementById("dialogBox");
  73     uploadBox = document.getElementById("uploadBox");
  74     dialogTitle = document.getElementById("dialogTitle");
  75     dialogContent = document.getElementById("dialogContent");
  76
  77     matita = new Object();
  78     matita.disambMode = matita.proofMode = false;
  79
  80     // hide sequent view at start
  81     initializeLayout();
  82     updateSide();
  83
  84     changeFile("test.ma");
  85
  86     // initialize keyboard events in the unlocked script
  87     init_keyboard(unlocked);
  88
  89     init_autotraces();
  90
  91   }
  92 }
  93
  94 function init_autotraces() {
  95     $("#unlocked .autotactic").tooltip({
  96       delay: 0,
  97       showURL: false,
  98       bodyHandler: function() {
  99         return (trace_of($(this)[0]));
 100       }
 101     });
 102     $("#locked .autotactic").tooltip({
 103       delay: 0,
 104       showURL: false,
 105       bodyHandler: function() {
 106         return (trace_of($(this)[0]));
 107       }
 108     });
 109 }
 110
 111 function trace_of(node) {
 112   return text_of_html(filterByClass(node.childNodes,"autotrace")[0]);
 113 }
 114
 115 function changeFile(name) {
 116     current_fname = name;
 117     matitaTitle.innerHTML = "Matita - cic:/matita/" + name;
 118 }
 119
 120 function init_keyboard(target)
 121 {
 122     if (target.addEventListener)
 123     {
 124 //       target.addEventListener("keydown",keydown,false);
 125        target.addEventListener("keypress",keypress,false);
 126 //       target.addEventListener("keyup",keyup,false);
 127 //       target.addEventListener("textInput",textinput,false);
 128     }
 129     else if (target.attachEvent)
 130     {
 131 //       target.attachEvent("onkeydown", keydown);
 132        target.attachEvent("onkeypress", keypress);
 133 //       target.attachEvent("onkeyup", keyup);
 134 //       target.attachEvent("ontextInput", textinput);
 135     }
 136     else
 137     {
 138 //       target.onkeydown= keydown;
 139        target.onkeypress= keypress;
 140 //       target.onkeyup= keyup;
 141 //       target.ontextinput= textinput;   // probably doesn't work
 142     }
 143
 144 }
 145
 146 function keyval(n)
 147 {
 148     if (n == null) return 'undefined';
 149     var s= '' + n;
 150     if (n >= 32 && n < 127) s+= ' (' + String.fromCharCode(n) + ')';
 151     while (s.length < 9) s+= ' ';
 152     return s;
 153 }
 154
 155 function string_of_key(n)
 156 {
 157     if (n == null) return 'undefined';
 158     return String.fromCharCode(n);
 159 }
 160
 161 function pressmesg(w,e)
 162 {
 163    debug(w + '  keyCode=' + keyval(e.keyCode) +
 164                  ' which=' + keyval(e.which) +
 165                  ' charCode=' + keyval(e.charCode) +
 166                  '\n          shiftKey='+e.shiftKey
 167               + ' ctrlKey='+e.ctrlKey
 168               + ' altKey='+e.altKey
 169               + ' metaKey='+e.metaKey);
 170 }
 171
 172 function suppressdefault(e,flag)
 173 {
 174    if (flag)
 175    {
 176        if (e.preventDefault) e.preventDefault();
 177        if (e.stopPropagation) e.stopPropagation();
 178    }
 179    return !flag;
 180 }
 181
 182 function restoreSelection(r) {
 183     unlocked.focus();
 184     if (r != null) {
 185         if (window.getSelection)//non IE and there is already a selection
 186         {
 187             var s = window.getSelection();
 188             if (s.rangeCount > 0)
 189                 s.removeAllRanges();
 190             s.addRange(r);
 191         }
 192         else
 193             if (document.createRange)//non IE and no selection
 194             {
 195                 window.getSelection().addRange(r);
 196             }
 197             else
 198                 if (document.selection)//IE
 199                 {
 200                     r.select();
 201                 }
 202     }
 203 }
 204
 205 function lookup_tex(texmacro)
 206 {
 207   texmacro = texmacro.substring(1);
 208   return unescape(macro2utf8[texmacro]);
 209 }
 210
 211 function strip_tags(tagname,classname)
 212 {
 213     var tags = unlocked.getElementsByTagName(tagname);
 214     if (is_defined(classname)) {
 215         tags = filterByClass(tags,classname);
 216     }
 217     for (i = 0; i < tags.length; i++) {
 218         var children = tags[i].childNodes;
 219         for (j = 0; j < children.length; j++) {
 220             tags[i].parentNode.insertBefore(children[j],tags[i]);
 221         }
 222     }
 223     while (tags.length > 0) {
 224       tags[0].parentNode.removeChild(tags[0]);
 225     }
 226 }
 227
 228 function strip_interpr() {
 229         strip_tags("A");
 230         alert("strip_interpr ended");
 231 }
 232
 233 function keypress(e)
 234 {
 235    if (!e) e= event;
 236    pressmesg('keypress',e);
 237    var s = string_of_key(e.charCode);
 238    strip_tags("span","error");
 239    if (s == " ") {
 240         j = getCursorPos();
 241         i = unlocked.innerHTML.html_to_matita().lastIndexOf('\\',j);
 242         if (i >= 0) {
 243           match = unlocked.innerHTML.html_to_matita().substring(i,j);
 244           sym = unescape_html(lookup_tex(match));
 245           if (sym != "undefined") {
 246              if (window.getSelection) { // non IE
 247                 savedRange.setStart(savedsc,savedso - (j-i));
 248                 savedRange.deleteContents();
 249                 savedRange.insertNode(document.createTextNode(sym));
 250                 savedsc.parentNode.normalize();
 251                 if (savedRange.collapsed) { // Mozilla
 252                   savedRange.setEnd(savedsc,savedRange.endOffset + sym.length);
 253                 }
 254                 savedRange.collapse(false);
 255              } else {
 256                 savedRange.moveStart(i-j);
 257                 savedRange.text(sym);
 258                 savedRange.collapse(false);
 259              }
 260              restoreSelection(savedRange);
 261              return suppressdefault(e,true);
 262           }
 263           else {
 264              // restoreSelection(0);
 265              return suppressdefault(e,false);
 266           }
 267         }
 268         else return suppressdefault(e,false);
 269    } else {
 270         return suppressdefault(e,false);
 271    }
 272 }
 273
 274 var logtxt = "";
 275
 276 function debug(txt)
 277 {
 278         // internet explorer (v.9) doesn't work with innerHTML
 279         // but google chrome's innerText is, in a sense, "write only"
 280         // what should we do?
 281         // logarea.innerText = txt + "\n" + logarea.innerText;
 282         logtxt = /* logtxt + "\n" +*/ txt;
 283 }
 284
 285 function showLog() {
 286   logWin = window.open( "", "Matita Log",
 287      "width=600,height=450,status,scrollbars,resizable,screenX=20,screenY=40,left=20,top=40");
 288   logWin.document.write('<html><head><title>Matita Log' + '</title></head>');
 289   logWin.document.write('<body><textarea style="width:100%;height:100%;">' +
 290     logtxt + '</textarea></body></html>');
 291   logWin.document.close();
 292 }
 293
 294 function listhd(l)
 295 {
 296         ar = l.split("#");
 297         debug("hd of '" + l + "' = '" + ar[0] + "'");
 298         return (ar[0]);
 299 }
 300
 301 function listtl(l)
 302 {
 303         i = l.indexOf("#");
 304         tl = l.substr(i+1);
 305         debug("tl of '" + l + "' = '" + tl + "'");
 306         return (tl);
 307 }
 308
 309 function listcons(x,l)
 310 {
 311         debug("cons '" + x + "' on '" + l + "'");
 312         return (x + "#" + l);
 313 }
 314
 315 function listnil()
 316 {
 317         return ("");
 318 }
 319
 320 function list_append(l1,l2)
 321 { return (l1 + l2) }
 322
 323 function is_nil(l)
 324 {
 325         return (l == "");
 326 }
 327
 328 function fold_left (f,acc,l)
 329 {
 330         if (is_nil(l))
 331            { debug("'" + l + "' is fold end");
 332            return (acc); }
 333         else
 334            { debug("'" + l + "' is fold cons");
 335              return(fold_left (f,f(acc,(listhd(l))),listtl(l))); }
 336 }
 337
 338 function listiter (f,l)
 339 {
 340         if (is_nil(l))
 341         { debug("'" + l + "' is nil");
 342            return;
 343         }
 344         else
 345         {
 346            debug("'" + l + "' is not nil");
 347            f(listhd(l));
 348            listiter(f,listtl(l));
 349         }
 350 }
 351
 352 function listmap (f,l)
 353 {
 354         debug("listmap on " + l);
 355         if (is_nil(l))
 356            { debug("returning listnil");
 357              return(listnil());
 358            }
 359         else
 360            { debug("cons f(hd) map(f,tl)");
 361              return(f(listhd(l)) + "#" + listmap(f,listtl(l)));
 362            }
 363 }
 364
 365 var statements = listnil();
 366
 367 var goalarray;
 368 var metalist = listnil();
 369
 370 function pairmap (f,p)
 371 {
 372   debug("pairmap of '" + p + "'");
 373   ar = p.split("|");
 374   return (f(ar[0],ar[1]));
 375 }
 376
 377 function tripletmap (f,p)
 378 {
 379   debug("tripletmap of '" + p + "'");
 380   ar = p.split("|");
 381   return (f(ar[0],ar[1],ar[2]));
 382 }
 383
 384 function fst (p)
 385 {
 386   debug("fst");
 387   return (pairmap (function (a,b) { return (a); }, p));
 388 }
 389
 390 function p13 (p)
 391 {
 392   debug("p13");
 393   return (tripletmap (function (a,b,c) { return (a); }, p));
 394 }
 395
 396 function p23 (p)
 397 {
 398   debug("p23");
 399   return (tripletmap (function (a,b,c) { return (b); }, p));
 400 }
 401
 402 function p33 (p)
 403 {
 404   debug("f33");
 405   return (tripletmap (function (a,b,c) { return (c); }, p));
 406 }
 407
 408 function populate_goalarray(menv)
 409 {
 410   debug("metasenv.length = " + menv.length);
 411   if (menv.length == 0) {
 412       try {
 413           hideSequent();
 414       } catch (err) { };
 415   } else {
 416       showSequent();
 417       goalarray = new Array();
 418       metalist = listnil();
 419       var tmp_goallist = "";
 420       for (i = 0; i < menv.length; i++) {
 421         metano = menv[i].getAttribute("number");
 422         metaname = menv[i].childNodes[0].childNodes[0].data;
 423         goal = menv[i].childNodes[1].childNodes[0].data;
 424         debug ("found meta n. " + metano);
 425         debug ("found goal\nBEGIN" + goal + "\nEND");
 426         goalarray[metano] = goal;
 427         tmp_goallist = " <A href=\"javascript:switch_goal(" + metano + ")\">" + metaname + "</A>" + tmp_goallist;
 428         metalist = listcons(metano,metalist);
 429         debug ("goalarray[\"" + metano + "\"] = " + goalarray[metano]);
 430       }
 431       goals.innerHTML = tmp_goallist;
 432       debug("new metalist is '" + metalist + "'");
 433       if (is_nil(metalist)) {
 434         switch_goal();
 435       }
 436       else {
 437         switch_goal(listhd(metalist));
 438       }
 439   }
 440 }
 441
 442 function switch_goal(meta)
 443 {
 444   if (typeof meta == "undefined") {
 445     goalview.innerHTML = "";
 446   }
 447   else {
 448     debug("switch_goal " + meta + "\n" + goalarray[meta]);
 449     goalview.innerHTML = "<B>Goal ?" + meta + ":</B>\n\n" + goalarray[meta];
 450   }
 451 }
 452
 453 // the following is used to avoid escaping unicode, which results in
 454 // the server being unable to unescape the string
 455 String.prototype.sescape = function() {
 456         var patt1 = /%/gi;
 457         var patt2 = /=/gi;
 458         var patt3 = /&/gi;
 459         var patt4 = /\+/gi;
 460         var result = this;
 461         result = result.replace(patt1,"%25");
 462         result = result.replace(patt2,"%3D");
 463         result = result.replace(patt3,"%26");
 464         result = result.replace(patt4,"%2B");
 465         return (result);
 466 }
 467
 468 String.prototype.html_to_matita = function()
 469 {
 470         var patt1 = /<br(\/|)>/gi;
 471         var patt2 = /</gi
 472         var patt3 = />/gi
 473         var patt4 = /&lt;/gi;
 474         var patt5 = /&gt;/gi;
 475         var patt6 = /&nbsp;/gi;
 476         var result = this;
 477         result = result.replace(patt1,"\n");
 478         result = result.replace(patt2,"\005");
 479         result = result.replace(patt3,"\006");
 480         result = result.replace(patt4,"<");
 481         result = result.replace(patt5,">");
 482         result = result.replace(patt6," ");
 483         return (unescape(result));
 484 }
 485
 486 String.prototype.matita_to_html = function()
 487 {
 488         var patt1 = /</gi
 489         var patt2 = />/gi
 490         var patt3 = /\005/gi;
 491         var patt4 = /\006/gi;
 492         var result = this;
 493         result = result.replace(patt1,"&lt;");
 494         result = result.replace(patt2,"&gt;");
 495         result = result.replace(patt3,"<");
 496         result = result.replace(patt4,">");
 497         return (unescape(result));
 498 }
 499
 500 function is_defined(x)
 501 {
 502         return (typeof x != "undefined");
 503 }
 504
 505 /* servicename: name of the service being called
 506  * reqbody: text of the request
 507  * processResponse: processes the server response
 508  *     (takes the response text in input, undefined in case of error)
 509  */
 510 function callServer(servicename,processResponse,reqbody)
 511 {
 512         var req = null;
 513         // pause();
 514         if (window.XMLHttpRequest)
 515         {
 516                 req = new XMLHttpRequest();
 517         }
 518         else if (window.ActiveXObject)
 519         {
 520                 try {
 521                                 req = new ActiveXObject("Msxml2.XMLHTTP");
 522                 } catch (e)
 523                 {
 524                         try {
 525                                 req = new ActiveXObject("Microsoft.XMLHTTP");
 526                                 } catch (e) {}
 527                 }
 528         }
 529         req.onreadystatechange = function()
 530         {
 531
 532                 rs = req.readyState;
 533
 534                 if(rs == 4)
 535                 {
 536                         stat = req.status;
 537                         stxt = req.statusText;
 538                         if(stat == 200)
 539                         {
 540                           debug(req.responseText);
 541                           if (window.DOMParser) {
 542                             parser=new DOMParser();
 543                             xmlDoc=parser.parseFromString(req.responseText,"text/xml");
 544                           }
 545                           else // Internet Explorer
 546                           {
 547                             xmlDoc=new ActiveXObject("Microsoft.XMLDOM");
 548                             xmlDoc.async="false";
 549                             xmlDoc.loadXML(req.responseText);
 550                           }
 551                           processResponse(xmlDoc);
 552                         } else {
 553                           processResponse();
 554                         }
 555                 }
 556         };
 557         req.open("POST", servicename); // + escape(unlocked.innerHTML), true);
 558         req.setRequestHeader("Content-type","application/x-www-form-urlencoded");
 559         if (reqbody) {
 560                 req.send(reqbody);
 561         } else {
 562                 req.send();
 563         }
 564
 565 }
 566
 567 function advanceForm1()
 568 {
 569         processor = function(xml) {
 570                 if (is_defined(xml)) {
 571                         var parsed = xml.getElementsByTagName("parsed")[0];
 572                         var ambiguity = xml.getElementsByTagName("ambiguity")[0];
 573                         var disamberr = xml.getElementsByTagName("disamberror")[0];
 574                         if (is_defined(parsed)) {
 575                         // debug("advance: received response\nBEGIN\n" + req.responseText + "\nEND");
 576                             var len = parseInt(parsed.getAttribute("length"));
 577                             // len0 = unlocked.innerHTML.length;
 578                             var unescaped = unlocked.innerHTML.html_to_matita();
 579                             var parsedtxt = parsed.childNodes[0].wholeText;
 580                             //parsedtxt = unescaped.substr(0,len);
 581                             var unparsedtxt = unescaped.substr(len);
 582                             lockedbackup += parsedtxt;
 583                             locked.innerHTML = lockedbackup;
 584                             unlocked.innerHTML = unparsedtxt.matita_to_html();
 585                             // len1 = unlocked.innerHTML.length;
 586                             // len2 = len0 - len1;
 587                             var len2 = parsedtxt.length;
 588                             var metasenv = xml.getElementsByTagName("meta");
 589                             populate_goalarray(metasenv);
 590                             init_autotraces();
 591                             statements = listcons(len2,statements);
 592                             unlocked.scrollIntoView(true);
 593                         }
 594                         else if (is_defined(ambiguity)) {
 595                             var start = parseInt(ambiguity.getAttribute("start"));
 596                             var stop = parseInt(ambiguity.getAttribute("stop"));
 597                             var choices = xml.getElementsByTagName("choice");
 598
 599                             matita.ambiguityStart = start;
 600                             matita.ambiguityStop = stop;
 601                             matita.unlockedbackup = unlocked.innerHTML.html_to_matita();
 602                             matita.interpretations = [];
 603
 604                             var unlockedtxt = unlocked.innerHTML.html_to_matita();
 605                             var pre = unlockedtxt.substring(0,start).matita_to_html();
 606                             var mid = unlockedtxt.substring(start,stop).matita_to_html();
 607                             var post = unlockedtxt.substring(stop).matita_to_html();
 608                             unlocked.innerHTML = pre +
 609                                     "<span class=\"error\" title=\"disambiguation error\">" +
 610                                     mid + "</span>" + post;
 611
 612                             var title = "<H3>Ambiguous input</H3>";
 613                             disambcell.innerHTML = title;
 614                             for (i = 0;i < choices.length;i++) {
 615                                 matita.interpretations[i] = new Object();
 616
 617                                 var href = choices[i].getAttribute("href");
 618                                 var title = choices[i].getAttribute("title");
 619                                 var desc = choices[i].childNodes[0].nodeValue;
 620
 621                                 matita.interpretations[i].href = href;
 622                                 matita.interpretations[i].title = title;
 623                                 matita.interpretations[i].desc = desc;
 624
 625                                 var choice = document.createElement("input");
 626                                 choice.setAttribute("type","radio");
 627                                 choice.setAttribute("name","interpr");
 628                                 choice.setAttribute("href",href);
 629                                 choice.setAttribute("title",title);
 630                                 if (i == 0) choice.setAttribute("checked","");
 631
 632                                 disambcell.appendChild(choice);
 633                                 disambcell.appendChild(document.createTextNode(desc));
 634                                 disambcell.appendChild(document.createElement("br"));
 635                             }
 636
 637                             var okbutton = document.createElement("input");
 638                             okbutton.setAttribute("type","button");
 639                             okbutton.setAttribute("value","OK");
 640                             okbutton.setAttribute("onclick","do_disambiguate()");
 641                             var cancelbutton = document.createElement("input");
 642                             cancelbutton.setAttribute("type","button");
 643                             cancelbutton.setAttribute("value","Cancel");
 644                             cancelbutton.setAttribute("onclick","cancel_disambiguate()");
 645
 646                             disambcell.appendChild(okbutton);
 647                             disambcell.appendChild(cancelbutton);
 648
 649                             disable_toparea();
 650
 651                             matita.disambMode = true;
 652                             updateSide();
 653                         }
 654                         else if (is_defined(disamberr)) {
 655                             set_cps(disamberr.childNodes);
 656                             matita.unlockedbackup = unlocked.innerHTML.html_to_matita();
 657                             matita.disambMode = true;
 658                             disable_toparea();
 659                             next_cp(0);
 660                         }
 661                         else {
 662                             var error = xml.getElementsByTagName("error")[0];
 663                             unlocked.innerHTML = error.childNodes[0].wholeText;
 664                             // debug(xml.childNodes[0].nodeValue);
 665                         }
 666                 } else {
 667                         debug("advance failed");
 668                 }
 669                 resume();
 670         };
 671         pause();
 672         callServer("advance",processor,"body=" + (unlocked.innerHTML.html_to_matita()).sescape());
 673
 674 }
 675
 676 // get or set <choicepoint>'s (in case of disamb error)
 677 function get_cps() {
 678         return matita.choicepoints
 679 }
 680
 681 function set_cps(cps) {
 682         matita.choicepoints = cps;
 683 }
 684
 685 // get radio buttons for <choice>'s in a given cp
 686 function get_choice_opts(i) {
 687    var res = [];
 688    var choices = get_cps()[i].childNodes;
 689    for (var j = 0;j < choices.length;j++) {
 690       var href = choices[j].getAttribute("href");
 691       var title = choices[j].getAttribute("title");
 692       var desc;
 693       if (is_defined(title)) {
 694            desc = title;
 695       } else if (is_defined(href)) {
 696            desc = href;
 697       } else {
 698            desc = "Preliminary error";
 699       }
 700
 701       res[j] = document.createElement("input");
 702       res[j].setAttribute("type","radio");
 703       res[j].setAttribute("name","choice");
 704       res[j].setAttribute("choicepointno",i);
 705       res[j].setAttribute("choiceno",j);
 706       res[j].setAttribute("href",href);
 707       res[j].setAttribute("title",title);
 708       res[j].setAttribute("desc",desc);
 709
 710       if (j == 0) res[j].setAttribute("checked","");
 711   }
 712   return res;
 713 }
 714
 715 // get radio buttons for <failure>'s in a given choice
 716 function get_failure_opts(i,j) {
 717    var res = [];
 718    var failures = get_cps()[i].childNodes[j].childNodes;
 719    for (var k = 0;k < failures.length;k++) {
 720       var start = failures[k].getAttribute("start");
 721       var stop = failures[k].getAttribute("stop");
 722       var title = failures[k].getAttribute("title");
 723
 724       res[k] = document.createElement("input");
 725       res[k].setAttribute("type","radio");
 726       res[k].setAttribute("name","failure");
 727       res[k].setAttribute("choicepointno",i);
 728       res[k].setAttribute("choiceno",j);
 729       res[k].setAttribute("failureno",k);
 730       res[k].setAttribute("start",start);
 731       res[k].setAttribute("stop",stop);
 732       res[k].setAttribute("title",title);
 733
 734       if (k == 0) res[k].setAttribute("checked","");
 735   }
 736   return res;
 737 }
 738
 739 function next_cp(curcp) {
 740         var cp = get_cps()[curcp];
 741         var start = parseInt(cp.getAttribute("start"));
 742         var stop = parseInt(cp.getAttribute("stop"));
 743
 744         matita.errorStart = start;
 745         matita.errorStop = stop;
 746         // matita.unlockedbackup = unlocked.innerHTML.html_to_matita();
 747
 748         var unlockedtxt = matita.unlockedbackup;
 749         var pre = unlockedtxt.substring(0,start).matita_to_html();
 750         var mid = unlockedtxt.substring(start,stop).matita_to_html();
 751         var post = unlockedtxt.substring(stop).matita_to_html();
 752         unlocked.innerHTML = pre +
 753                 "<span class=\"error\" title=\"disambiguation failed\">" +
 754                 mid + "</span>" + post;
 755
 756         var title = "<H3>Disambiguation failed</H3>";
 757         disambcell.innerHTML = title;
 758         var choices = get_choice_opts(curcp);
 759         for (var i = 0;i < choices.length;i++) {
 760             disambcell.appendChild(choices[i]);
 761             disambcell.appendChild(document.createTextNode(choices[i].getAttribute("desc")));
 762             disambcell.appendChild(document.createElement("br"));
 763         }
 764
 765         // update index of the next choicepoint
 766         new_curcp = (curcp + 1) % get_cps().length;
 767
 768         var okbutton = document.createElement("input");
 769         okbutton.setAttribute("type","button");
 770         okbutton.setAttribute("value","OK");
 771         okbutton.setAttribute("onclick","show_failures()");
 772         var cancelbutton = document.createElement("input");
 773         cancelbutton.setAttribute("type","button");
 774         cancelbutton.setAttribute("value","Close");
 775         cancelbutton.setAttribute("onclick","cancel_disambiguate()");
 776         var tryagainbutton = document.createElement("input");
 777         tryagainbutton.setAttribute("type","button");
 778         if (new_curcp > 0) {
 779             tryagainbutton.setAttribute("value","Try something else");
 780         } else {
 781             tryagainbutton.setAttribute("value","Restart");
 782         }
 783         tryagainbutton.setAttribute("onclick","next_cp(" + new_curcp + ")");
 784
 785         disambcell.appendChild(okbutton);
 786         disambcell.appendChild(tryagainbutton);
 787         disambcell.appendChild(cancelbutton);
 788
 789         //disable_toparea();
 790
 791         //matita.disambMode = true;
 792         updateSide();
 793
 794 }
 795
 796 function show_failures() {
 797
 798         var choice = document.getElementsByName("choice")[get_checked_index("choice")];
 799         var cpno = parseInt(choice.getAttribute("choicepointno"));
 800         var choiceno = parseInt(choice.getAttribute("choiceno"));
 801         var choicedesc = choice.getAttribute("desc");
 802
 803         var title = "<H3>Disambiguation failed</H3>";
 804         var subtitle = "<p>Errors at node " + cpno + " = " + choicedesc + "</p>";
 805
 806         disambcell.innerHTML = title + subtitle;
 807         var failures = get_failure_opts(cpno,choiceno);
 808         for (var i = 0;i < failures.length;i++) {
 809             disambcell.appendChild(failures[i]);
 810             disambcell.appendChild(document.createTextNode(failures[i].getAttribute("title")));
 811             disambcell.appendChild(document.createElement("br"));
 812         }
 813
 814         var okbutton = document.createElement("input");
 815         okbutton.setAttribute("type","button");
 816         okbutton.setAttribute("value","Show error loc");
 817         okbutton.setAttribute("onclick","show_err()");
 818         var cancelbutton = document.createElement("input");
 819         cancelbutton.setAttribute("type","button");
 820         cancelbutton.setAttribute("value","Close");
 821         cancelbutton.setAttribute("onclick","cancel_disambiguate()");
 822         var backbutton = document.createElement("input");
 823         backbutton.setAttribute("type","button");
 824         backbutton.setAttribute("value","<< Back");
 825         backbutton.setAttribute("onclick","next_cp(" + cpno + ")");
 826
 827         disambcell.appendChild(backbutton);
 828         disambcell.appendChild(okbutton);
 829         disambcell.appendChild(cancelbutton);
 830
 831 }
 832
 833 function show_err() {
 834         var radios = document.getElementsByName("failure");
 835         for (i = 0; i < radios.length; i++) {
 836             if (radios[i].checked) {
 837                 var start = radios[i].getAttribute("start");
 838                 var stop = radios[i].getAttribute("stop");
 839                 var title = radios[i].getAttribute("title");
 840                 var unlockedtxt = matita.unlockedbackup;
 841                 var pre = unlockedtxt.substring(0,start).matita_to_html();
 842                 var mid = unlockedtxt.substring(start,stop).matita_to_html();
 843                 var post = unlockedtxt.substring(stop).matita_to_html();
 844                 unlocked.innerHTML = pre +
 845                         "<span class=\"error\" title=\"Disambiguation failure\">" +
 846                         mid + "</span>" + post;
 847                 break;
 848             }
 849         }
 850 }
 851
 852 function gotoBottom()
 853 {
 854         processor = function(xml) {
 855                 if (is_defined(xml)) {
 856                         // debug("goto bottom: received response\nBEGIN\n" + req.responseText + "\nEND");
 857                         var parsed = xml.getElementsByTagName("parsed");
 858                         var localized = xml.getElementsByTagName("localized")[0];
 859                         var ambiguity = xml.getElementsByTagName("ambiguity")[0];
 860                         var generic_err = xml.getElementsByTagName("error")[0];
 861                         for (var i = 0;i < parsed.length; i++) {
 862                           var len = parsed[i].getAttribute("length");
 863                           // len0 = unlocked.innerHTML.length;
 864                           var unescaped = unlocked.innerHTML.html_to_matita();
 865                           // the browser may decide to split textnodes: use wholeText!
 866                           var parsedtxt = parsed[i].childNodes[0].wholeText;
 867                           //parsedtxt = unescaped.substr(0,len);
 868                           var unparsedtxt = unescaped.substr(len);
 869                           lockedbackup += parsedtxt;
 870                           locked.innerHTML = lockedbackup; //.matita_to_html();
 871                           unlocked.innerHTML = unparsedtxt.matita_to_html();
 872                           // len1 = unlocked.innerHTML.length;
 873                           var len2 = parsedtxt.length;
 874                           statements = listcons(len2,statements);
 875                         }
 876                         unlocked.scrollIntoView(true);
 877                         metasenv = xml.getElementsByTagName("meta");
 878                         init_autotraces();
 879                         populate_goalarray(metasenv);
 880
 881                         if (is_defined(ambiguity)) {
 882                             var start = parseInt(ambiguity.getAttribute("start"));
 883                             var stop = parseInt(ambiguity.getAttribute("stop"));
 884                             var choices = xml.getElementsByTagName("choice");
 885
 886                             matita.ambiguityStart = start;
 887                             matita.ambiguityStop = stop;
 888                             matita.unlockedbackup = unlocked.innerHTML.html_to_matita();
 889                             matita.interpretations = [];
 890
 891                             var unlockedtxt = unlocked.innerHTML.html_to_matita();
 892                             var pre = unlockedtxt.substring(0,start).matita_to_html();
 893                             var mid = unlockedtxt.substring(start,stop).matita_to_html();
 894                             var post = unlockedtxt.substring(stop).matita_to_html();
 895                             unlocked.innerHTML = pre +
 896                                     "<span class=\"error\" title=\"disambiguation error\">" +
 897                                     mid + "</span>" + post;
 898
 899                             var title = "<H3>Ambiguous input</H3>";
 900                             disambcell.innerHTML = title;
 901                             for (i = 0;i < choices.length;i++) {
 902                                 matita.interpretations[i] = new Object();
 903
 904                                 var href = choices[i].getAttribute("href");
 905                                 var title = choices[i].getAttribute("title");
 906                                 var desc = choices[i].childNodes[0].nodeValue;
 907
 908                                 matita.interpretations[i].href = href;
 909                                 matita.interpretations[i].title = title;
 910                                 matita.interpretations[i].desc = desc;
 911
 912                                 var choice = document.createElement("input");
 913                                 choice.setAttribute("type","radio");
 914                                 choice.setAttribute("name","interpr");
 915                                 choice.setAttribute("href",href);
 916                                 choice.setAttribute("title",title);
 917                                 if (i == 0) choice.setAttribute("checked","");
 918
 919                                 disambcell.appendChild(choice);
 920                                 disambcell.appendChild(document.createTextNode(desc));
 921                                 disambcell.appendChild(document.createElement("br"));
 922                             }
 923
 924                             var okbutton = document.createElement("input");
 925                             okbutton.setAttribute("type","button");
 926                             okbutton.setAttribute("value","OK");
 927                             okbutton.setAttribute("onclick","do_disambiguate()");
 928                             var cancelbutton = document.createElement("input");
 929                             cancelbutton.setAttribute("type","button");
 930                             cancelbutton.setAttribute("value","Cancel");
 931                             cancelbutton.setAttribute("onclick","cancel_disambiguate()");
 932
 933                             disambcell.appendChild(okbutton);
 934                             disambcell.appendChild(cancelbutton);
 935
 936                             disable_toparea();
 937
 938                             matita.disambMode = true;
 939                             updateSide();
 940                         }
 941                         if (is_defined(localized)) {
 942                             unlocked.innerHTML = localized.wholeText;
 943                         }
 944                         if (is_defined(generic_err)) {
 945                             debug("Unmanaged error:\n" ^ generic_err.wholeText);
 946                         }
 947                 } else {
 948                         debug("goto bottom failed");
 949                 }
 950                 resume();
 951         };
 952         pause();
 953         callServer("bottom",processor,"body=" + (unlocked.innerHTML.html_to_matita()).sescape());
 954 }
 955
 956
 957 function gotoTop()
 958 {
 959         processor = function(xml) {
 960                 if (is_defined(xml)) {
 961                   if (xml.childNodes[0].textContent != "ok") {
 962                      debug("goto top failed");
 963                   }
 964                   else
 965                         statements = listnil();
 966                         /*
 967                         lockedlen = locked.innerHTML.length - statementlen;
 968                         statement = locked.innerHTML.substr(lockedlen, statementlen);
 969                         locked.innerHTML = locked.innerHTML.substr(0,lockedlen);
 970                         unlocked.innerHTML = statement + unlocked.innerHTML;
 971                         */
 972                         unlocked.innerHTML = lockedbackup + unlocked.innerHTML;
 973                         lockedbackup = "";
 974                         locked.innerHTML = lockedbackup;
 975                         init_autotraces();
 976                         hideSequent();
 977                         unlocked.scrollIntoView(true);
 978                 } else {
 979                         debug("goto top failed");
 980                 }
 981                 resume();
 982         };
 983         pause();
 984         callServer("top",processor,"body=" + (unlocked.innerHTML.html_to_matita()).sescape());
 985
 986 }
 987 function gotoPos(offset)
 988 {
 989         if (!is_defined(offset)) {
 990                 offset = getCursorPos();
 991         }
 992         processor = function(xml) {
 993                 if (is_defined(xml)) {
 994                         parsed = xml.getElementsByTagName("parsed")[0];
 995                         len = parseInt(parsed.getAttribute("length"));
 996                         // len0 = unlocked.innerHTML.length;
 997                         unescaped = unlocked.innerHTML.html_to_matita();
 998                         parsedtxt = parsed.childNodes[0].wholeText;
 999                         //parsedtxt = unescaped.substr(0,len);
1000                         unparsedtxt = unescaped.substr(len);
1001                         lockedbackup += parsedtxt;
1002                         locked.innerHTML = lockedbackup; //.matita_to_html();
1003                         unlocked.innerHTML = unparsedtxt.matita_to_html();
1004                         // len1 = unlocked.innerHTML.length;
1005                         len2 = parsedtxt.length;
1006                         metasenv = xml.getElementsByTagName("meta");
1007                         // populate_goalarray(metasenv);
1008                         statements = listcons(len2,statements);
1009                         unlocked.scrollIntoView(true);
1010                         // la populate non andrebbe fatta a ogni passo
1011                         if (offset <= len) {
1012                                 init_autotraces();
1013                                 populate_goalarray(metasenv);
1014                                 resume();
1015                         } else {
1016                                 gotoPos(offset - len);
1017                         }
1018                 } else {
1019                         init_autotraces();
1020                         unlocked.scrollIntoView(true);
1021                         populate_goalarray(metasenv);
1022                         resume();
1023                 }
1024         }
1025         pause();
1026         callServer("advance",processor,"body=" + (unlocked.innerHTML.html_to_matita()).sescape());
1027 }
1028
1029 function retract()
1030 {
1031         processor = function(xml) {
1032                 if (typeof xml != "undefined") {
1033                         // debug("advance: received response\nBEGIN\n" + req.responseText + "\nEND");
1034                         statementlen = parseInt(listhd(statements));
1035                         statements = listtl(statements);
1036                         /*
1037                         lockedlen = locked.innerHTML.length - statementlen;
1038                         statement = locked.innerHTML.substr(lockedlen, statementlen);
1039                         locked.innerHTML = locked.innerHTML.substr(0,lockedlen);
1040                         unlocked.innerHTML = statement + unlocked.innerHTML;
1041                         */
1042                         lockedlen = lockedbackup.length - statementlen;
1043                         statement = lockedbackup.substr(lockedlen, statementlen);
1044                         lockedbackup = lockedbackup.substr(0,lockedlen);
1045                         locked.innerHTML = lockedbackup;
1046                         unlocked.innerHTML = statement + unlocked.innerHTML;
1047                         metasenv = xml.getElementsByTagName("meta");
1048                         init_autotraces();
1049                         populate_goalarray(metasenv);
1050                         unlocked.scrollIntoView(true);
1051                 } else {
1052                         debug("retract failed");
1053                 }
1054                 resume();
1055         };
1056         debug("retract 1");
1057         pause();
1058         callServer("retract",processor);
1059         debug("retract 2");
1060 }
1061
1062 function openFile()
1063 {
1064         processor = function(xml)
1065         {
1066                 if (is_defined(xml)) {
1067                         lockedbackup = "";
1068                         locked.innerHTML = lockedbackup;
1069                         unlocked.innerHTML = xml.documentElement.wholeText;
1070                 } else {
1071                         debug("file open failed");
1072                 }
1073         };
1074         callServer("open",processor,"file=" + escape(filename.value));
1075 }
1076
1077 function retrieveFile(thefile)
1078 {
1079         processor = function(xml)
1080         {
1081                 if (is_defined(xml)) {
1082                         changeFile(thefile);
1083                         lockedbackup = ""
1084                         locked.innerHTML = lockedbackup;
1085                         // code originally used in google chrome (problems with mozilla)
1086                         // debug(xml.getElementsByTagName("file")[0].childNodes[0].nodeValue);
1087                         // unlocked.innerHTML = xml.getElementsByTagName("file")[0].childNodes[0].nodeValue;
1088                         debug(xml.childNodes[0].textContent);
1089                         if (document.all) { // IE
1090                           unlocked.innerHTML = xml.childNodes[0].text;
1091                         } else {
1092                           unlocked.innerHTML = xml.childNodes[0].textContent;
1093                         }
1094                         init_autotraces();
1095
1096                 } else {
1097                         debug("file open failed");
1098                 }
1099         };
1100         abortDialog();
1101         callServer("open",processor,"file=" + escape(thefile));
1102 }
1103
1104 function showLibrary(title,callback,reloadDialog)
1105 {
1106         var req = null;
1107         dialogBox.reload = reloadDialog;
1108         // pause();
1109         if (window.XMLHttpRequest)
1110         {
1111                 req = new XMLHttpRequest();
1112         }
1113         else if (window.ActiveXObject)
1114         {
1115                 try {
1116                                 req = new ActiveXObject("Msxml2.XMLHTTP");
1117                 } catch (e)
1118                 {
1119                         try {
1120                                 req = new ActiveXObject("Microsoft.XMLHTTP");
1121                                 } catch (e) {}
1122                 }
1123         }
1124         req.onreadystatechange = function()
1125         {
1126
1127                 rs = req.readyState;
1128
1129                 if(rs == 4)
1130                 {
1131                         stat = req.status;
1132                         stxt = req.statusText;
1133                         if(stat == 200)
1134                         {
1135                           debug(req.responseText);
1136                           showDialog("<H2>" + title + "</H2>",req.responseText, callback);
1137                         }
1138                 }
1139         };
1140         req.open("POST", "viewlib"); // + escape(unlocked.innerHTML), true);
1141         req.setRequestHeader("Content-type","application/x-www-form-urlencoded");
1142         req.send();
1143
1144 }
1145
1146 function uploadDialog()
1147 {
1148         uploadBox.style.display = "block";
1149 }
1150
1151 function uploadOK()
1152 {
1153    var file = document.getElementById("uploadFilename").files[0];
1154    if (file) {
1155        var filecontent = file.getAsText("UTF-8");
1156        locked.innerHTML = lockedbackup;
1157        unlocked.innerHTML = filecontent;
1158        uploadBox.style.display = "none";
1159    }
1160 //   if (file) {
1161 //      var reader = new FileReader();
1162 //      reader.readAsText(file, "UTF-8");
1163 //       reader.onloadend = function (evt) {
1164 //         lockedbackup = "";
1165 //           locked.innerHTML = lockedbackup
1166 //           unlocked.innerHTML = evt.target.result;
1167 //           uploadBox.style.display = "none";
1168 //       }
1169 //       reader.onerror = function (evt) {
1170 //         debug("file open failed");
1171 //           uploadBox.style.display = "none";
1172 //      }
1173 //   }
1174 }
1175
1176 function openDialog()
1177 {
1178         callback = function (fname) { retrieveFile(fname); };
1179         showLibrary("Open file", callback, openDialog);
1180 }
1181
1182 function saveDialog()
1183 {
1184         callback = function (fname) {
1185           abortDialog();
1186           saveFile(fname,
1187                    (locked.innerHTML.html_to_matita()).sescape(),
1188                    (unlocked.innerHTML.html_to_matita()).sescape(),
1189                    false,saveDialog);
1190         };
1191         showLibrary("Save file as", callback, saveDialog);
1192 }
1193
1194 function newDialog()
1195 {
1196         callback = function (fname) {
1197           abortDialog();
1198           saveFile(fname,"","",false,newDialog,true);
1199         };
1200         showLibrary("Create new file", callback, newDialog);
1201 }
1202
1203
1204 function saveFile(fname,lockedtxt,unlockedtxt,force,reloadDialog,reloadFile)
1205 {
1206         if (!is_defined(reloadFile)) { reloadFile = true };
1207         if (!is_defined(fname)) {
1208             fname = current_fname;
1209             lockedtxt = (locked.innerHTML.html_to_matita()).sescape();
1210             unlockedtxt = (unlocked.innerHTML.html_to_matita()).sescape();
1211             force = true;
1212             // when force is true, reloadDialog is not needed
1213         }
1214         processor = function(xml) {
1215                 if (is_defined(xml)) {
1216                   if (xml.childNodes[0].textContent != "ok") {
1217                     if (confirm("File already exists. All existing data will be lost.\nDo you want to proceed anyway?")) {
1218                        saveFile(fname,lockedtxt,unlockedtxt,true,reloadDialog,reloadFile);
1219                     } else {
1220                       reloadDialog();
1221                     }
1222                   } else {
1223                     changeFile(fname);
1224                     debug("file saved!");
1225                     if (reloadFile) { retrieveFile(fname); }
1226                   }
1227                 } else {
1228                         debug("save file failed");
1229                 }
1230                 resume();
1231         };
1232         if (is_defined(fname)) {
1233           pause();
1234           callServer("save",processor,"file=" + escape(fname) +
1235                                     "&locked=" + lockedtxt +
1236                                     "&unlocked=" + unlockedtxt +
1237                                     "&force=" + force);
1238         }
1239         else { debug("no file selected"); }
1240 }
1241
1242 function createDir() {
1243    abortDialog();
1244    dirname = prompt("New directory name:\ncic:/matita/","newdir");
1245    if (dirname != null) {
1246         processor = function(xml) {
1247                 if (is_defined(xml)) {
1248                   if (xml.childNodes[0].textContent != "ok") {
1249                       alert("An error occurred :-(");
1250                   }
1251                 } else {
1252                       alert("An error occurred :-(");
1253                 }
1254                 dialogBox.reload();
1255         };
1256         pause();
1257         callServer("save",processor,"file=" + escape(dirname) +
1258                                     "&locked=&unlocked=&force=false&dir=true");
1259    } else {
1260       dialogBox.reload();
1261    }
1262 }
1263
1264 function commitAll()
1265 {
1266         processor = function(xml) {
1267                 if (is_defined(xml)) {
1268                         debug(xml.getElementsByTagName("details")[0].textContent);
1269                         alert("Commit executed: see details in the log.\n\n" +
1270                               "NOTICE: this message does NOT imply (yet) that the commit was successful.");
1271                 } else {
1272                         alert("Commit failed!");
1273                 }
1274                 resume();
1275         };
1276         pause();
1277         callServer("commit",processor);
1278 }
1279
1280 function updateAll()
1281 {
1282         processor = function(xml) {
1283                 if (is_defined(xml)) {
1284                         alert("Update executed.\n\n" +
1285                               "Details:\n" +
1286                               xml.getElementsByTagName("details")[0].textContent);
1287                 } else {
1288                         alert("Update failed!");
1289                 }
1290                 resume();
1291         };
1292         pause();
1293         callServer("update",processor);
1294 }
1295
1296 var goalcell;
1297
1298 function hideSequent() {
1299         matita.proofMode = false;
1300         updateSide();
1301 }
1302
1303 function showSequent() {
1304         matita.proofMode = true;
1305         updateSide();
1306 }
1307
1308 function showDialog(title,content,callback) {
1309   dialogTitle.innerHTML = title;
1310   dialogContent.innerHTML = content;
1311   dialogBox.callback = callback;
1312
1313   //Get the screen height and width
1314   var maskHeight = $(document).height();
1315   var maskWidth = $(window).width();
1316
1317   //Set heigth and width to mask to fill up the whole screen
1318   $('#mask').css({'width':maskWidth,'height':maskHeight});
1319
1320   //transition effect
1321   $('#mask').fadeIn(100);
1322   $('#mask').fadeTo(200,0.8);
1323
1324   //Get the window height and width
1325   var winH = $(window).height();
1326   var winW = $(window).width();
1327
1328   //Set the popup window to center
1329   $('#dialogBox').css('top',  winH/2-$('#dialogBox').height()/2);
1330   $('#dialogBox').css('left', winW/2-$('#dialogBox').width()/2);
1331
1332   //transition effect
1333   $('#dialogBox').fadeIn(200);
1334
1335   dialogBox.style.display = "block";
1336 }
1337
1338 function abortDialog(dialog) {
1339   $('#mask').hide();
1340   dialogBox.style.display = "none";
1341 }
1342
1343 function removeElement(id) {
1344   var element = document.getElementById(id);
1345   element.parentNode.removeChild(element);
1346 }
1347
1348 var savedsc;
1349 var savedso;
1350
1351 function getCursorPos() {
1352   var cursorPos;
1353   if (window.getSelection) {
1354     var selObj = window.getSelection();
1355     savedRange = selObj.getRangeAt(0);
1356     savedsc = savedRange.startContainer;
1357     savedso = savedRange.startOffset;
1358     //cursorPos =  findNode(selObj.anchorNode.parentNode.childNodes, selObj.anchorNode) + selObj.anchorOffset;
1359     cursorPos =  findNode(unlocked.childNodes, selObj.anchorNode,0) + selObj.anchorOffset;
1360     /* FIXME the following works wrong in Opera when the document is longer than 32767 chars */
1361     return(cursorPos);
1362   }
1363   else if (document.selection) {
1364     savedRange = document.selection.createRange();
1365     var bookmark = savedRange.getBookmark();
1366     /* FIXME the following works wrong when the document is longer than 65535 chars */
1367     cursorPos = bookmark.charCodeAt(2) - 11; /* Undocumented function [3] */
1368     return(cursorPos);
1369   }
1370 }
1371
1372 function findNode(list, node, acc) {
1373   for (var i = 0; i < list.length; i++) {
1374     if (list[i] == node) {
1375    //   debug("success " + i);
1376       return acc;
1377     }
1378     if (list[i].hasChildNodes()) {
1379        try {
1380    //      debug("recursion on node " + i);
1381          return (findNode(list[i].childNodes,node,acc))
1382        }
1383        catch (e) { /* debug("recursion failed"); */ }
1384     }
1385     sandbox = document.getElementById("sandbox");
1386     dup = list[i].cloneNode(true);
1387     sandbox.appendChild(dup);
1388 //    debug("fail " + i + ": " + sandbox.innerHTML);
1389     acc += sandbox.innerHTML.html_to_matita().length;
1390     sandbox.removeChild(dup);
1391   }
1392   throw "not found";
1393 }
1394
1395 function test () {
1396   debug("cursor test: " + unlocked.innerHTML.substr(0,getCursorPos()));
1397 }
1398
1399 function get_checked_index(name) {
1400         var radios = document.getElementsByName(name);
1401         for (i = 0; i < radios.length; i++) {
1402             if (radios[i].checked) {
1403                     return i;
1404             }
1405         }
1406         return null;
1407 }
1408
1409 function cancel_disambiguate() {
1410         matita.disambMode = false;
1411         enable_toparea();
1412         enable_editing();
1413         updateSide();
1414 }
1415
1416 function do_disambiguate() {
1417         var i = get_checked_index("interpr");
1418         if (i != null) {
1419             var pre = matita.unlockedbackup
1420                       .substring(0,matita.ambiguityStart).matita_to_html();
1421             var mid = matita.unlockedbackup
1422                       .substring(matita.ambiguityStart,matita.ambiguityStop)
1423                       .matita_to_html();
1424             var post = matita.unlockedbackup
1425                        .substring(matita.ambiguityStop).matita_to_html();
1426
1427             var href = matita.interpretations[i].href;
1428             var title = matita.interpretations[i].title;
1429
1430             if (is_defined(title)) {
1431                 mid = "<A href=\"" + href + "\" title=\"" + title + "\">" + mid + "</A>";
1432             } else {
1433                 mid = "<A href=\"" + href + "\">" + mid + "</A>";
1434             }
1435
1436             unlocked.innerHTML = pre + mid + post;
1437
1438             matita.disambMode = false;
1439             enable_toparea();
1440             enable_editing();
1441             updateSide();
1442         }
1443 }
1444
1445 function do_showerror() {
1446         var i = get_checked_index("choice");
1447         if (i != null) {
1448             var pre = matita.unlockedbackup
1449                       .substring(0,matita.ambiguityStart).matita_to_html();
1450             var mid = matita.unlockedbackup
1451                       .substring(matita.ambiguityStart,matita.ambiguityStop)
1452                       .matita_to_html();
1453             var post = matita.unlockedbackup
1454                        .substring(matita.ambiguityStop).matita_to_html();
1455
1456             var href = matita.interpretations[i].href;
1457             var title = matita.interpretations[i].title;
1458
1459             if (is_defined(title)) {
1460                 mid = "<A href=\"" + href + "\" title=\"" + title + "\">" + mid + "</A>";
1461             } else {
1462                 mid = "<A href=\"" + href + "\">" + mid + "</A>";
1463             }
1464
1465             unlocked.innerHTML = pre + mid + post;
1466
1467         }
1468 }
1469
1470 function readCookie(name) {
1471         var nameEQ = name + "=";
1472         var ca = document.cookie.split(';');
1473         for(var i=0;i < ca.length;i++) {
1474                 var c = ca[i];
1475                 while (c.charAt(0)==' ') c = c.substring(1,c.length);
1476                 if (c.indexOf(nameEQ) == 0) return c.substring(nameEQ.length,c.length);
1477         }
1478         return null;
1479 }
1480
1481 function delete_cookie ( cookie_name )
1482 {
1483   var cookie_date = new Date();  // current date & time
1484   cookie_date.setTime ( cookie_date.getTime() - 1 );
1485   document.cookie = cookie_name += "=; expires=" + cookie_date.toGMTString();
1486 }
1487
1488 function delete_session()
1489 {
1490         delete_cookie("session");
1491 }
1492
1493 function disable_toparea() {
1494         var offset = $('#toparea').offset();
1495         $('#whitemask').css('top',offset.top);
1496         $('#whitemask').css('left',offset.left);
1497         $('#whitemask').css('width',$('#toparea').outerWidth() + "px");
1498         $('#whitemask').css('height',$('#toparea').outerHeight() + "px");
1499         $('#whitemask').fadeTo('fast',0.7);
1500 }
1501
1502 function enable_toparea() {
1503         $('#whitemask').hide();
1504 }
1505
1506 function disable_editing() {
1507         unlocked.contentEditable = false;
1508 }
1509
1510 function enable_editing() {
1511         unlocked.contentEditable = true;
1512 }
1513
1514 function pause()
1515 {
1516         // advanceButton.disabled = true;
1517         // retractButton.disabled = true;
1518         // cursorButton.disabled = true;
1519         // bottomButton.disabled = true;
1520         disable_toparea();
1521         disable_editing();
1522 }
1523
1524 function resume()
1525 {
1526         // advanceButton.disabled = false;
1527         // retractButton.disabled = false;
1528         // cursorButton.disabled = false;
1529         // bottomButton.disabled = false;
1530         enable_toparea();
1531         enable_editing();
1532 }
1533