//
// javaScript ComboBox
//
// (C) 2007 [email protected]
//
// 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 for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software Foundation Inc.,
// 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
//
 
// 21/08/07     first version
// 24/08/07 save and restore state
// 26/08/07 now works with Firefox
// 26/08/07 added style 1
// 27/08/07 added optional width parameter
// 28/08/07 don't add empty strings to select box
// 28/08/07 escape cookie values
// 14/09/07 fixed bug selecting first item
//
// code demonstrates the difficulties of getting something simple to work in both IE and Firefox.
//
 
//
// static Factory constructor
//
ComboBox.Factory = FUNCTION(style, id, maxoptions, width)
{
     EVAL("window[\"" + id + "\"] = new ComboBox(" + style + ", \"" + id + "\"" + ((maxoptions == NULL) ? "" : ", " + maxoptions) + ((width == NULL) ? "" : ", " + width) + ");");
}
 
//
// restore state
//
ComboBox.prototype.restoreState = FUNCTION()
{
 
     FUNCTION getCookie(NAME, xdefault) {
          VAR nameEQ = NAME + "=";
          VAR ca = document.cookie.split(';');
          FOR (VAR i = 0; i < ca.length; i++) {
               VAR c = ca[i];
               WHILE (c.charAt(0) == ' ') 
                    c = c.substring(1, c.length);
               IF (c.indexOf(nameEQ) == 0)
                    RETURN unescape(c.substring(nameEQ.length, c.length));
          }
          RETURN xdefault;
     }
 
     THIS.string = getCookie(THIS.id + "string", "");
     THIS.noptions = getCookie(THIS.id + "noptions", 0);
     FOR (i = 0; i < THIS.maxoptions; i++)
          THIS.option[i] = getCookie(THIS.id + "option" + i, "string " + (i+1));
     IF (THIS.noptions == 0)
          THIS.noptions = 2;
 
     //alert("string = \"" + this.string + "\"");
     //alert("noptions = " + this.noptions);
     //for (i = 0; i < this.noptions; i++)
     //     alert(this.option[i]);
 
}
 
//
// save state
//
ComboBox.prototype.saveState = FUNCTION()
{
 
     FUNCTION setCookie(NAME, value, days) {
          expires = "";
          IF (days) {
               VAR date = NEW Date();
               date.setTime(date.getTime() + (days*24*60*60*1000));
               expires = "; expires=" + date.toGMTString();
          }
          document.cookie = NAME + "=" + escape(value) + expires + "; path=/";
     }
 
     //alert("saveState");
 
     setCookie(THIS.id + "string", THIS.txt.value, 100);
     setCookie(THIS.id + "noptions", THIS.options.length, 100);
     FOR (i = 0; i < THIS.options.length; i++)
          setCookie(THIS.id + "option" + i, THIS.options[i].value, 100);
 
     //alert(document.cookie)
 
}
 
//
// constructor
//
FUNCTION ComboBox(style, id, maxoptions, width)
{
     THIS.style = style;
     THIS.id = id;
     THIS.maxoptions = ((maxoptions == NULL) || (maxoptions < 4)) ? 4 : maxoptions;
 
     THIS.isIE = document.all;     // too clever??
     THIS.option = NEW Array();
     THIS.restoreState();
 
     IF (style == 1) {
 
          IF (width == NULL)
               width = 100;
 
          document.writeln("<span style=\"position:relative; width:", width, "px\">");
          document.writeln("  <select size=1 id=\"OPTIONS\" style=\"width:", width, "px\" onchange=\"javascript:", id, ".select();\">");
          FOR (i = 0; i < THIS.noptions; i++)
               document.writeln("  <option value=\"", THIS.option[i], "\">", THIS.option[i], "</option>");
          document.writeln("  </select>");
          document.writeln("<input type=text id=\"TXT\" value=\"", THIS.string, "\" style=\"position:absolute; left:0px; width:", THIS.isIE ? width-18 : width-20, "px", THIS.isIE ? "" : "; top:-1px", "\">");
          document.writeln("</span>");
 
 
     } ELSE {
 
          document.writeln("<select size=", THIS.noptions, " id=\"OPTIONS\" style=\"visibility:hidden; position:absolute; z-Index:999\" onblur=\"javascript:", id, ".hide();\" onclick=\"javascript:", id, ".select();\">");
         FOR (i = 0; i < THIS.noptions; i++)
              document.writeln("  <option value=\"", THIS.option[i], "\" tabIndex=-1>", THIS.option[i], "</option>");
          document.writeln("</select>");
          document.writeln("<input type=text id=\"TXT\" value=\"", THIS.string, "\"", ((THIS.width) ? "" : " style=\"width:" + width + "\""), ">");
          document.writeln("<button on", THIS.isIE ? "mousedown" : "click", "=\"javascript:", id, ".show();\">...</button>");
 
     }
 
     THIS.txt = document.getElementById("TXT");
     THIS.options = document.getElementById("OPTIONS");
     THIS.txt.id = NULL;
     THIS.options.id = NULL;
     THIS.options.selectedIndex = -1;     // {joj 14/9/07}
 
}
 
//
// show
//
ComboBox.prototype.show = FUNCTION() {
     //alert("show");
     THIS.add();                    // re-order
     offx = offy = 0;
     VAR parent = THIS.txt;
     WHILE (parent.offsetParent) {
          offx += parent.offsetLeft;
          offy += parent.offsetTop;
          parent = parent.offsetParent;
     }
     THIS.options.style.top = (offy + THIS.txt.offsetHeight) + "px";
     THIS.options.style.left = offx + "px";
     THIS.options.style.width = THIS.txt.offsetWidth + "px";
     THIS.options.style.visibility = "visible";
     THIS.options.FOCUS();
}
 
//
// select
//
ComboBox.prototype.select = FUNCTION() {
     //alert("select");
     THIS.txt.value = THIS.options[THIS.options.selectedIndex].value;
     THIS.options.selectedIndex = -1;     // {joj 14/9/07}
     IF (THIS.style == 0)
          THIS.options.style.visibility = "hidden";
}
 
//
// clear
//
ComboBox.prototype.clear = FUNCTION() {
     //alert("clear");
     THIS.txt.value = "";
}
 
//
// hide
//
ComboBox.prototype.hide = FUNCTION () {
     //alert("hide");
     THIS.options.style.visibility = "hidden";
     THIS.options.selectedIndex = -1;
}
 
//
// add
//
ComboBox.prototype.add = FUNCTION(str) {
 
     //alert("add");
 
     str = THIS.txt.value;
     IF (str == "")
          RETURN;
 
     //
     // see if option already present
     //
     sz = THIS.options.length;
     FOR (i = 0; i < sz; i++) {
          IF (THIS.options[i].value == str)
               BREAK;
     }
 
     //
     // nothing to do if matches first option
     //
     IF (i == 0)
          RETURN;
 
 
     //
     // NOT found - insert new option
     // found      - re-order to make first option
     //
     IF (i >= sz) {     // NOT found
 
          IF (sz < THIS.maxoptions) {
               THIS.options[sz] = NEW Option('new text','new value');
               sz += 1;
               IF (THIS.style == 0)
                    THIS.options.size = sz;
          }
 
          FOR (i = sz - 1; i > 0; i--)
               THIS.options[i].value = THIS.options[i].innerHTML = THIS.options[i-1].value;
          THIS.options[0].value = THIS.options[0].innerHTML = str;
 
     } ELSE {
 
          value = THIS.options[i].value;
          FOR (j = i; j > 0; j--)
               THIS.options[j].value = THIS.options[j].innerHTML = THIS.options[j-1].value;
          THIS.options[0].value = THIS.options[0].innerHTML = value;
 
     }
 
}
 
//
// update
//
ComboBox.prototype.update = FUNCTION () {
     //alert("update");
     THIS.add();
     THIS.saveState();
     RETURN THIS.txt.value;
}