// Online Flashcards JavaScript application
  // 
  // Please click the 'back' button on your browser right now.
  //
  // (c)1997, Andy Lyons, http://nersp.nerdc.ufl.edu/~alyons
  // All Rights Reserved
  // Feel free to use but maintain this portion for proper creditting

  function MakeArray(n) {
   this.length = n;
   for (var i = 1; i <= n; i++) { 
     this[i] = "" }
     return this
  }

  function ReadyMove() {
    if (document.myform.viewfirst.checked) {
      if ((document.myform.displayo[0].checked) && (document.myform.csent.value=="")) {
        ShowC()
        return false
      } else if ((document.myform.displayo[1].checked) && (document.myform.esent.value=="")) {
        ShowE()
        return false
      } else {
        return true
      }
    } else {
      return true
    }
  }

  function NextSent() {
   if (ReadyMove()) {
     if (CurNum < MaxSent) {
      CurNum = CurNum + 1    
      ShowSent(true)
     }
     else {
      alert("Sorry! You are already at the end.")
     }    
   }
  }

  function TagAndNext() {
   if (ReadyMove()) {
    if (CurNum < MaxSent) {
     Tagged[Ord[CurNum]] = !Tagged[Ord[CurNum]]
     if (Tagged[Ord[CurNum]]) {
       TotalTagged += 1
     } else {
       TotalTagged -= 1
     }
     CurNum = CurNum + 1
     ShowSent(true)
    }
    else {
     alert("Sorry! You are already at the end.")
    }    
   }
  }

  function PrevSent() {
   if (ReadyMove()) {
    if (CurNum > 1) {
     CurNum = CurNum - 1    
     ShowSent(true)
    }
    else {
     alert("Sorry! You are already at the beginning.")
    }    
   }
  }

  function FirstSent() {
    CurNum = 1    
    ShowSent(true)
  }

  function LastSent() {
    CurNum = MaxSent    
    ShowSent(true)
  }

  function ShowC() {
    if ((document.myform.displayo[1].checked) || (document.myform.displayo[2].checked)) {
      alert("Whoops!")
    } else {
      document.myform.csent.value = q[Ord[CurNum]]
    }
  }

  function ShowE() {
    if ((document.myform.displayo[0].checked) || (document.myform.displayo[2].checked)) {
      alert("In the dark, all cats are grey.")
    } else {
      document.myform.esent.value = a[Ord[CurNum]]
    }
  }

  function ShowSent(wipe) {
    if (document.myform.displayo[1].checked) {
      document.myform.csent.value=q[Ord[CurNum]]
      document.myform.esent.value="" 
    }

    else if (document.myform.displayo[0].checked) {
      document.myform.csent.value=""
      document.myform.esent.value=a[Ord[CurNum]]
    }

    else {
      document.myform.csent.value=q[Ord[CurNum]]
      document.myform.esent.value=a[Ord[CurNum]]
    }

    if (wipe) {
      document.myform.goodtry.value = ""
    }    

    document.myform.txt_counter.value=CurNum + " of " + MaxSent 
     //  document.myform.tagged.checked = Tagged[Ord[CurNum]] -- omit if TAGGING disabled
    //document.myform.txt_tagged.value = TotalTagged
  }

  function Alphabetize(LeftComparison) {
    document.myform.esent.value="Alphabetizing, please wait..."
    document.myform.esent.focus()
    document.myform.esent.select()
    document.myform.csent.focus()
    var Inserted = false
    var Comparison = false
    Ord[1] = 1

    for (var i = 2; i <= MaxSent; i++) { 
      document.myform.csent.value = (MaxSent - i)
      document.myform.csent.select()
      InsertAfterThis = 0
      for (var j = 1; j <= (i-1); j++) {
        if (LeftComparison) {
          Comparison = (q[i].toUpperCase() > q[Ord[j]].toUpperCase())
        } else {
          Comparison = (a[i].toUpperCase() > a[Ord[j]].toUpperCase())
        }

        if (Comparison) {
          InsertAfterThis = j
        }     
      }
        
      Inserted = false
      for (var j = (i+1); j >= 1; j--) { 
        if (!Inserted) {
          if (j == (InsertAfterThis + 1)) {
            Ord[j] = i
            Inserted = true
          } else {
            Ord[j] = Ord[j-1]
          }
        }          
      }
    }

    // If we're resorting all the words, then reset OrdTemp
    if (MaxSent == NumWords) {
      for (var i = 1; i <= MaxSent; i++) { 
        OrdTemp[i] = Ord[i]
      }
    }
    CurNum = 1
    document.myform.csent.value = "DONE"
    document.myform.csent.select()
    ShowSent(true)
  }

  function Randomize() {
    document.myform.esent.value="Shuffling, please wait..."
    document.myform.esent.focus()
    document.myform.esent.select()
    document.myform.csent.focus()

     for (var i = 1; i <= MaxSent; i++) { 
       document.myform.csent.value = (MaxSent*2) - i
       document.myform.csent.select()
       NumTaken[i] = 0
       OrdTemp2[i] = Ord[i]
     }

     today = new Date();
     seed = today.getTime();

     for (var i = 1; i <= MaxSent; i++) { 
       seed = Math.round(Math.abs(Math.sin (seed)*1000000)) 
       OrdBuff[i] = 1 + seed % MaxSent
       NumTaken[OrdBuff[i]] += 1
     }
 
     var CurOrd = 1
     var CurCount = 1

     while (CurCount <= MaxSent) {
       document.myform.csent.value = (MaxSent - CurCount)
       document.myform.csent.select()

       if (NumTaken[CurCount] > 0) { 
       
         for (var k = 1; k <= MaxSent; k++) { 
           if (OrdBuff[k] == CurCount) {
             // added Ord[CurOrd] below
             Ord[k] = OrdTemp2[CurOrd]
             CurOrd += 1
           }
         }   
       }
       CurCount += 1
     }

     if (MaxSent == NumWords) {
       for (var i = 1; i <= MaxSent; i++) { 
         OrdTemp[i] = Ord[i]
       }
     }

     CurNum = 1
     document.myform.csent.value = "DONE"
     document.myform.csent.select()
     ShowSent(true)
  }

  function TagMe() {
    Tagged[Ord[CurNum]] = document.myform.tagged.checked
    if (document.myform.tagged.checked) {
      TotalTagged += 1 
    } else {
      TotalTagged -= 1
    }
    document.myform.txt_tagged.value = TotalTagged
  }

  function getCookieVal (offset) {
    var endstr = document.cookie.indexOf (";", offset);
    if (endstr == -1)
      endstr = document.cookie.length;
    return unescape(document.cookie.substring(offset, endstr));
  }

  function GetCookie (name) {
    var arg = name + "=";
    var alen = arg.length;
    var clen = document.cookie.length;
    var i = 0;
    while (i < clen) {
      var j = i + alen;
      if (document.cookie.substring(i, j) == arg)
        return getCookieVal (j);
      i = document.cookie.indexOf(" ", i) + 1;
      if (i == 0) break; 
    }
    return null;
  }

  function SetCookie (name,value,expires,path,domain,secure) {
    document.cookie = name + "=" + escape (value) +
      ((expires) ? "; expires=" + expires.toGMTString() : "") +
      ((path) ? "; path=" + path : "") +
      ((domain) ? "; domain=" + domain : "") +
      ((secure) ? "; secure" : "");
  }

  function SupportCookies() {
    exp_date = new Date()
    exp_date.setTime(exp_date.getTime() + (6 * 30 * 24 * 60 * 60 * 1000))
    SetCookie ("test","OK",exp_date,location.pathname);
    if (GetCookie("test")) {
      return true
    } else {
      return false
    }
  }

  function SaveToDisk() {
    ToSaveOrNot = true
    if (!SupportCookies()) {
      alert("Whoops, your browser does not seem to support Java Script.")
      ToSaveOrNot = false

    } else if (TotalTagged == 0) {
      alert("Whoops, that won't work.")  
      ToSaveOrNot = false
    } 

    else if (GetCookie("tags")) {
      if (!confirm("Einige Karteikarten dieser Web-Seite sind bereits auf Diskette gespeichert. Sollen sie ersetzt werden?")) {
        ToSaveOrNot = false        
      }         
    }

    if (ToSaveOrNot) {
      tagbuild = ""
      for (var i = 1; i <= MaxSent; i++) { 
        if (Tagged[i]) {
          tagbuild += i + "_"
        }
      }
      tagbuild = tagbuild.substring(0,tagbuild.length-1)
      exp_date = new Date()
      exp_date.setTime(exp_date.getTime() + (6 * 30 * 24 * 60 * 60 * 1000))
      SetCookie ("tags",tagbuild,exp_date, location.pathname);
      alert(TotalTagged + " flashcards tags have been saved to disk. Now, when you come back to this web page another time (on this same computer), you can retag these flashcards again by clicking on 'Load tags from disk'.");
    }
  }

  function LoadFromDisk() {
    ToTagOrNot = true
    tagbuild = GetCookie("tags")
    if (!SupportCookies()) {
      alert("Whoops, your browser does not seem to support Java Script.")
      ToSaveOrNot = false
    } else if (!tagbuild) {
      alert("Sorry, this won't work.")
      ToTagOrNot = false
    }

    else if (TotalTagged != 0) {
      if (!confirm("There are already " + TotalTagged + " tagged flashcards on this web page. Do you want to untag these and then retag the ones that have been previously saved on disk?")) {
        ToTagOrNot = false;
      } else {
        SetTags(false)
        if (MaxSent != NumWords) {
          ShowAll()
        }
      }
    }

    if (ToTagOrNot) {
      tagsarray = tagbuild.split("_");
      for (var i = 0; i <= MaxSent-1; i++) { 
        if (tagsarray[i] == null) {
          break
        } else {
          TotalTagged += 1
          Tagged[tagsarray[i]] = true
        }
      }
      ShowSent(false)
      alert(TotalTagged + " flashcards have been retagged from disk. Click 'View tagged only' to go through them.")
    }
  }

  function ToggleTags() {
    for (var i = 1; i <= MaxSent; i++) { 
      Tagged[Ord[i]] = !Tagged[Ord[i]]
    }
    TotalTagged = MaxSent - TotalTagged
    ShowSent(false)
  }

  function ShowTags() {
    if (TotalTagged == 0) {
       alert("There must be a least one tagged flashcard before you can hide all the others.")
    } else {

    // Reset the Ord array according to the Tagged setting
    var j = 0
    for (var i = 1; i <= MaxSent; i++) { 
      if (Tagged[Ord[i]]) {
        j += 1
        OrdBuff[j] = Ord[i]
      }
    }
    MaxSent = j
    for (var i = 1; i <= MaxSent; i++) { 
      Ord[i] = OrdBuff[i]
    }

    CurNum = 1
    ShowSent(true)
  } // TotalTagged <> 0
  }

  function ShowAll() {
    if (MaxSent == NumWords) {
      alert("Oh no! That doesn't work and Nora doesn't know why.")
    } else {
      MaxSent = NumWords
      for (var i = 1; i <= MaxSent; i++) { 
        Ord[i] = OrdTemp[i]
      }
      CurNum = 1
      ShowSent(true)
    }
  }

  function SetTags(tf) {
    for (var i = 1; i <= MaxSent; i++) { 
      Tagged[Ord[i]] = tf
    }
    if (tf) {
      TotalTagged = MaxSent
    } else {
      TotalTagged = 0
    }
    ShowSent(false)
  }

  function WindowList() {
    if (TotalTagged == 0) {
       alert("This function displays all the tagged words as a list. You must have at least one record tagged. Tag one or more words and then try again.")
    } else {
       msg=open("","TaggedWords"+NumWindows, "toolbar=yes,menubar=yes,scrollbars=yes,location=yes,status=yes");
       NumWindows++
       var QuotChar = '"'
       msg.document.writeln("<HEAD><TITLE>Tagged Words</TITLE></HEAD><BODY BGCOLOR=#FFFF80>");
       msg.document.writeln("<p><b>" + TotalTagged + " of " + NumWords + " records from <A HREF=" + QuotChar + "javascript:alert('To go back to the flashcard page, close this window.')" + QuotChar + ">" + document.title + "</A>.</b></p><TABLE BORDER=1 WIDTH=100% CELLPADDING=2>");

       for (var i = 1; i <= MaxSent; i++) { 
         if (Tagged[Ord[i]]) {
           msg.document.writeln("<TR VALIGN=TOP><TD>" + q[Ord[i]] + "</TD><TD>" + a[Ord[i]] + "</TD></TR>");    
         }
       }
       msg.document.writeln("</TABLE></BODY>");
       msg.document.close()
    }
  }

  var MaxSent = NumWords
  var NumWindows = 1
  q = new MakeArray(MaxSent)
  a = new MakeArray(MaxSent)
  InitVars()

  var CurNum = 1
  var TotalTagged = 0

  NumTaken = new MakeArray(MaxSent)
  Ord = new MakeArray(MaxSent)
  Tagged = new MakeArray(MaxSent)
  OrdTemp = new MakeArray(MaxSent) 
  OrdTemp2 = new MakeArray(MaxSent)
  OrdBuff = new MakeArray(MaxSent)

  for (var i = 1; i <= MaxSent; i++) { 
    Ord[i] = i
    Tagged[i] = false
    OrdTemp[i] = i
  }