// JavaScript Document

// Wrapper to retrieve a DOM object.  This function (should) contain browser 
// checks and extra convienence functionality. 
function g_getObj(objId) { 
    if (document.getElementById) { 
        return document.getElementById(objId); 
    } 
  
    return null; 
}

function removeUnwantedCharacters(searchField)
{
	var invalidchars=Array("~","#","}","{","'","!","@","$","%","^","&","*","(",")","-","_","+","=","{","}","[","]","\\","|",":",";","\"","'",",","<",".",",",">","?","/");
	var searchterm=Trim(searchField.value);
	if(searchterm.length == 1 )
	{
		for(var i=0;i<invalidchars.length;i++)
		{
			if(searchterm==invalidchars[i])
			{
				searchField.value="";
				return;
			}
		}
	}
	
	
	searchField.value = searchField.value.replace(" - "," ");
}
function verifySearchTerm(searchFieldId) {
    var searchField = g_getObj(searchFieldId);
    removeUnwantedCharacters(searchField);  	
    if (searchField == null) {
        window.alert("You must enter an item or topic in the search field.");
        return false;
    } else if (Trim(searchField.value).length == 0 ) {
        window.alert("You must enter an item or topic in the search field.");
        return false;
    }    
    return true;
}

function verifySearchTermObject(searchFieldId) {

    var searchField = document.forms[searchFieldId].elements["kw"];
    removeUnwantedCharacters(searchField);  	
    if (searchField == null) {
        window.alert("You must enter an item or topic in the search field.");
        return false;
    } else if (Trim(searchField.value).length == 0 ) {
        window.alert("You must enter an item or topic in the search field.");
        return false;
    }    
    return true;
}

function Trim(str) { 
	while(str.charAt(0) == (" ")){ 
		str = str.substring(1);
	}
	while(str.charAt(str.length-1) == " " ){ 
		str = str.substring(0,str.length-1);
	}
	return str;
}