// Implements AC_GenerateObj() function. This is a generic function used to generate
// object/embed/param tags. It is used by higher level api functions.

/************** LOCALIZABLE GLOBAL VARIABLES ****************/

var MSG_EvenArgs = 'The %s function requires an even number of arguments.'
                 + '\nArguments should be in the form "atttributeName","attributeValue",...';
var MSG_SrcRequired = "The %s function requires that a src be passed in as one of the arguments.";

/******************** END LOCALIZABLE **********************/


// Substitutes values for %s in a string.
// Usage: AC_sprintf("The %s function requires %s arguments.","foo()","4");
function AC_sprintf(str){
  for (var i=1; i < arguments.length; i++){
    str = str.replace(/%s/,arguments[i]);
  }
  return str;
}
		
// Checks that args, the argument list to check, has an even number of 
// arguments. Alerts the user if an odd number of arguments is found.
function AC_checkArgs(args,callingFn){
  var retVal = true;
  // If number of arguments isn't even, show a warning and return false.
  if (parseFloat(args.length/2) != parseInt(args.length/2)){
    alert(sprintf(MSG_EvenArgs,callingFn));
    retVal = false;
  }
  return retVal;
}
	
function AC_GenerateObj(callingFn, useXHTML, classid, args)
{

   if (!AC_checkArgs(args,callingFn))
  {
    return;
  }

  // Initialize variables
  var tagStr = '';
  var currArg = '';
  var closer = (useXHTML) ? '/>' : '>';
  var srcFound = false;
  var embedStr = '<embed';
  var paramStr = '';
  var embedNameAttr = '';
  var objStr = '<object classid="' + classid + '"';

  // Spin through all the argument pairs, assigning attributes and values to the object,
  // param, and embed tags as appropriate.
  for (var i=0; i < args.length; i=i+2){
    currArg = args[i].toLowerCase();    

    if (currArg == "src"){
        paramStr += '<param name="' + args[i] + '" value="' + args[i+1] + '"' + closer + '\n';
        embedStr += ' ' + args[i] + '="' + args[i+1] + '"';
        srcFound = true;
    }
    else if (   currArg == "width" 
              || currArg == "height" 
              || currArg == "align" 
              || currArg == "vspace" 
              || currArg == "hspace" 
              || currArg == "class" 
              || currArg == "title" 
              || currArg == "accesskey" 
              || currArg == "tabindex"){
      objStr += ' ' + args[i] + '="' + args[i+1] + '"';
      embedStr += ' ' + args[i] + '="' + args[i+1] + '"';
    }
    else if (currArg == "id"){
      objStr += ' ' + args[i] + '="' + args[i+1] + '"';
      // Only add the name attribute to the embed tag if a name attribute 
      // isn't already there. This is what Dreamweaver does if the user
      // enters a name for a movie in the PI: it adds id to the object
      // tag, and name to the embed tag.
      if (embedNameAttr == "")
        embedNameAttr = ' name="' + args[i+1] + '"';
    }
    else if (currArg == "name"){
      objStr += ' ' + args[i] + '="' + args[i+1] + '"';
      // Replace the current embed tag name attribute with the one passed in.
      embedNameAttr = ' ' + args[i] + '="' + args[i+1] + '"';
    }    
    // This is an attribute we don't know about. Assume that we should add it to the 
    // param and embed strings.
    else{
      paramStr += '<param name="' + args[i] + '" value="' + args[i+1] + '"' + closer + '\n'; 
      embedStr += ' ' + args[i] + '="' + args[i+1] + '"';
    }
  }

  // Tell the user that a src is required, if one was not passed in.
  if (!srcFound){
    alert(AC_sprintf(MSG_SrcRequired,callingFn));
    return;
  }

  if (embedNameAttr)
    embedStr += embedNameAttr;	

  // Close off the object and embed strings
  objStr += '>\n';
  embedStr += '></embed>\n'; 

  // Assemble the three tag strings into a single string.
  tagStr = objStr + paramStr + embedStr + "</object>\n"; 
  
  document.write(tagStr);
 
}