/* This script is Copyright (c) Paul McFedries and 
Logophilia Limited (http://www.mcfedries.com/).
Permission is granted to use this script as long as 
this Copyright notice remains in place.*/

function CalculateTotal(frm) {
    var order_total = 0

    // Run through all the form fields
    for (var i=0; i < frm.elements.length; ++i) {

        // Get the current field
        form_field = frm.elements[i]

        // Get the field's name
        form_name = form_field.name

        // Is it a "product" field?
        if (form_name.substring(0,4) == "PROD") {

            // If so, extract the price from the name
        	item_price = parseFloat(form_name.substring(form_name.lastIndexOf("_") + 1))
        	switch (item_price) {
        		case 950: item_price = 9.50; break;
        		case 750: item_price = 7.50; break;
        	}


            // Get the quantity
            item_quantity = parseInt(form_field.value)

            // Update the order total
            if (item_quantity >= 0) {
                order_total += item_quantity * item_price
            }
        }
    }

    // Display the total rounded to two decimal places
    frm.TOTAL.value = round_decimals(order_total, 2)
}

function round_decimals(original_number, decimals) {
    var result1 = original_number * Math.pow(10, decimals)
    var result2 = Math.round(result1)
    var result3 = result2 / Math.pow(10, decimals)
    return pad_with_zeros(result3, decimals)
}

function pad_with_zeros(rounded_value, decimal_places) {

    // Convert the number to a string
    var value_string = rounded_value.toString()
    
    // Locate the decimal point
    var decimal_location = value_string.indexOf(".")

    // Is there a decimal point?
    if (decimal_location == -1) {
        
        // If no, then all decimal places will be padded with 0s
        decimal_part_length = 0
        
        // If decimal_places is greater than zero, tack on a decimal point
        value_string += decimal_places > 0 ? "." : ""
    }
    else {

        // If yes, then only the extra decimal places will be padded with 0s
        decimal_part_length = value_string.length - decimal_location - 1
    }
    
    // Calculate the number of decimal places that need to be padded with 0s
    var pad_total = decimal_places - decimal_part_length
    
    if (pad_total > 0) {
        
        // Pad the string with 0s
        for (var counter = 1; counter <= pad_total; counter++) 
            value_string += "0"
        }
    return value_string
}

// enable/disable text inputs and wipe if need be
function checkboxFlip(checkbox, text) {
value = document.getElementById(checkbox).checked;
tb = document.getElementById(text);
	$text = $('#' + text);
	if (value == true) {
		$text.removeAttr('readonly');
		//document.getElementById(text).disabled=false;
	}
	else {
		$text.val(0);
		//document.getElementById(text).value=0;
		CalculateTotal(tb.form);
		//document.getElementById(text).disabled=true;
		$text.attr('readonly', 'readonly');
	}
}