/*
 * Util.js: miscellaneous helper functions
 */

/*
 * Gets the link pointing to a course details page.
 * @param course The course object. We'll use it's uid
 */
function SearchUtil_getCourseUrl(course) {
	return "search.action?uid="+course.getID() + "&view=details";
}

/*
 * Adds the given text to the given input field.
 */
function Util_addContentsToField(id, abbrev) {
	var input = document.getElementById(id);
	input.value = abbrev + ", " + input.value;
}

/*
 * Formats a price (an integer) for display on the page.
 */
function Util_formatPrice(total_cents) {
  var dollars = parseInt(total_cents / 100, 10);
  var cents = parseInt(total_cents % 100, 10);
  if (cents < 10)
      cents = '0' + cents;
  return ('$' + dollars + '.' + cents);
}

/*
 * Adds an event to a DOM element in a cross-browser way.
 * @param object the DOM element on which to add the event
 * @param eventname the name of the event (e.g., 'click')
 * @param handler the handler function (or object) to use
 */
function Util_addEvent(object, eventname, handler) {
	/* IE uses proprietary attachEvent. Everybody else uses w3c addEventListener. */
	if (object.attachEvent)
		object.attachEvent('on'+eventname, handler);
	else
		object.addEventListener(eventname, handler, false);
}

/*
 * Adds an Option to a Select field.
 * @param select the DOM Select object 
 * @param option the DOM Option object
 */
function Util_addOptionToSelect(select, option) {
        /* 
         * We're using the existence of attachEvent to determine if it's IE,
         * because it has the function we want, but requires a non-standard
         * way to call it.
         */
        if (select.attachEvent)
                select.add(option);
        else
                select.add(option, null);
}

/*
 * Assuming that the following is public domain from
 * http://binnyva.blogspot.com/2005/10/dump-function-javascript-equivalent-of.html
 */
 
/**
* Function : dump()
* Arguments: The data - array,hash(associative array),object
*    The level - OPTIONAL
* Returns  : The textual representation of the array.
* This function was inspired by the print_r function of PHP.
* This will accept some data as the argument and return a
* text that will be a more readable version of the
* array/hash/object that is given.
*/
function Util_dump(arr,max,level) {
var dumped_text = "";
if(!level) level = 0;
if(!max)   max = 5;

if (max > level)
	return '';

//The padding given at the beginning of the line.
var level_padding = "";
for(var j=0;j<level+1;j++) level_padding += "    ";

if(typeof(arr) == 'object') { //Array/Hashes/Objects
 for(var item in arr) {
  var value = arr[item];
 
  if(typeof(value) == 'object') { //If it is an array,
   dumped_text += level_padding + "'" + item + "' ...\n";
   dumped_text += Util_dump(value,max,level+1);
  } else {
   dumped_text += level_padding + "'" + item + "' => \"" + value + "\"\n";
  }
 }
} else { //Stings/Chars/Numbers etc.
 dumped_text = "===>"+arr+"<===("+typeof(arr)+")";
}
return dumped_text;
} 

/*
 * If in debug mode, this brings up a Javascript alert when an assertion fails.
 */
function Util_assert(arg) {

}

function Util_max(a, b) {
        return (a > b ? a : b);
}

/*
 * Returns all the elements of [minuend] which are not also in [subtrahend].
 */
function Util_setDifference(minuend, subtrahend) {
	var minuendHash = [];
	for (var ii in minuend) {
	    minuendHash[minuend[ii]] = true;
	}
	for (var ii in subtrahend) {
	    delete minuendHash[subtrahend[ii]];
	}
	var result = [];
	for (var item in minuendHash) {
	    result.push(item);
	}
	return result;
}

function Util_setUnion(a, b) {
        return Util_setDifference(a, b).concat(b);
}

function Util_map(f, list) {
	var result = new Array(list.length);
	for (var ii in list) {
	    result[ii] = f(list[ii]);
	}
	return result;
}

function Util_filter(f, list) {
        var result = new Array(list.length);
        for (var ii in list) {
            if (f(list[ii])) {
                result[ii] = list[ii];
            }
        }
        return result;
}

function Util_findPos(obj) {
	var curleft = curtop = 0;
	if (obj.offsetParent) {
		curleft = obj.offsetLeft
		curtop = obj.offsetTop
		while (obj = obj.offsetParent) {
			curleft += obj.offsetLeft
			curtop += obj.offsetTop
		}
	}
	return [curleft,curtop];
}