///////////////////////////////////////////////////////////////////////////////
// strings.js:
// A variety of handy functions for working with strings.

function write(str)
{
	document.write(str);
}


function writeln(str)
{
	write(str + "\n");
}


function writebr(str)
{
	writeln(str + "<br>");
}


// trims spaces from the start and end of a string:
function trim(str)
{
	// check we have a value:
	if (str == null || str == "") return "";

	// make a new String for the result:
	var result = new String(str);

	// trim spaces from the start of result:
	while (result.charAt(0) == " ")
		result = result.substr(1, result.length - 1);

	// trim spaces from the end of result:
	while (result.charAt(result.length - 1) == " ")
		result = result.substr(0, result.length - 1);

	return result
}


// functions to add characters to start of a string until desired length reached:
function padLeft(value, width, chPad)
{
	// convert to a string:
	var result = value + "";
	// add pad characters until desired width is reached:
	while (result.length < width)
		result = chPad + result;
	return result;
}


// functions to add characters to end of a string until desired length reached:
function padRight(value, width, chPad)
{
	// convert to a string:
	var result = value + "";
	// add pad characters until desired width is reached:
	while (result.length < width)
		result = result + chPad;
	return result;
}


// function to make a string of substr repeated n times:
function stringOf(substr, n)
{
	var result = "";
	for (var i = 0; i < n; i++)
		result += substr;
	return result;
}


// returns n left-most characters from str:
function left(str, n)
{
	return str.substr(0, n);
}


// returns n right-most characters from str:
function right(str, n)
{
	return str.substr(str.length - n, n);
}


/////////////////////////////////////////////////////////////////////////////////////////
// Basic string and character functions:

// returns true if str is a string with length > 0
function isValidString(str)
{
	return (typeof(str) == "string" && str.length > 0)
}


// returns true if character ch is in string str:
function isIn(ch, str)
{
	return (str.indexOf(ch) >= 0);
}


/////////////////////////////////////////////////////////////////////////////////////////
// check ASCII codes:

var ASCII_A = 65;
var ASCII_Z = 90;
var ASCII_a = 97;
var ASCII_z = 122;
var ASCII_0 = 48;
var ASCII_9 = 57;

function isUpperCaseLetterCode(code)
{
	return (code >= ASCII_A) && (code <= ASCII_Z);
}


function isLowerCaseLetterCode(code)
{
	return (code >= ASCII_a) && (code <= ASCII_z);
}


function isLetterCode(code)
{
	return isUpperCaseLetterCode(code) || isLowerCaseLetterCode(code);
}


function isDigitCode(code)
{
	return (code >= ASCII_0) && (code <= ASCII_9);
}


function isAlphanumericCode(code)
{
	return isDigitCode(code) || isLetterCode(code);
}


/////////////////////////////////////////////////////////////////////////////////////////
// check ASCII characters:
function isUpperCaseLetter(ch)
{
	return isUpperCaseLetterCode(ch.charCodeAt(0));
}


function isLowerCaseLetter(ch)
{
	return isLowerCaseLetterCode(ch.charCodeAt(0));
}


function isLetter(ch)
{
	return isLetterCode(ch.charCodeAt(0));
}


function isDigit(ch)
{
	return isDigitCode(ch.charCodeAt(0));
}


function isAlphanumeric(ch)
{
	return isAlphanumericCode(ch.charCodeAt(0));
}


function isQuoteChar(ch)
{
	return ch == '"' || ch == "'" || ch == '`' || ch == '´' || ch == '’' || ch == '‘';
}


function isWhitespace(ch)
{
	return ch == ' ' || ch == '\n' || ch == '\t' || ch == '\r';
}


/////////////////////////////////////////////////////////////////////////////////////////
// check strings of digits or letters:

function isAllDigits(str)
{
	// check str:
	if (!isValidString(str))
		return false;

	// check that each character is a digit:
	for (var j = 0; j < str.length; j++)
		if (!isDigitCode(str.charCodeAt(j)))
			return false;

	// all ok:
	return true;
}


function isAllLetters(str)
{
	// check str:
	if (!isValidString(str))
		return false;

	// check that each character is a letter:
	for (var j = 0; j < str.length; j++)
		if (!isLetterCode(str.charCodeAt(j)))
			return false;

	// all ok:
	return true;
}


function isAllAlphanumeric(str)
{
	// check str:
	if (!isValidString(str))
		return false;

	// check that each character is a letter:
	var ch;
	for (var j = 0; j < str.length; j++)
	{
		ch = str.charCodeAt(j);
		if (!isDigitCode(ch) && !isLetterCode(ch))
			return false;
	}

	// all ok:
	return true;
}


function quote_replace(str)
{
	return str_replace("'", "''", str);
}


function uniformBreakTags(str)
{
	// replaces all versions of break tags with <br>
	str = str_replace('<BR', '<br', str);
	str = str_replace('<br >', '<br>', str);
	str = str_replace('<br />', '<br>', str);
	return str;
}


function stripHtmlTags(str)
{
	// removes html tags from a string:

	// check str:
	if (!isValidString(str))
		return false;

	var intag = false;
	var ch;
	var result = '';
	for (var j = 0; j < str.length; j++)
	{
		ch = str.charAt(j);
		if (!intag && ch == '<')
			intag = true;
		else if (intag && ch == '>')
			intag = false;
		else if (!intag)
		result += ch;
	}
	return result;
}


function capitalizeField(form, field)
{
	form[field].value = (form[field].value).toUpperCase();
}


function buildPhoneNumberString(phHome, phWork, phMobile)
{
	// make a string for the phone numbers:
	phoneNumbers = '';
	if (phHome != "")
	{
		if (phoneNumbers != '')
			phoneNumbers += ', ';
		phoneNumbers += "H: " + phHome;
	}
	if (phWork != "")
	{
		if (phoneNumbers != '')
			phoneNumbers += ', ';
		phoneNumbers += "W: " + phWork;
	}
	if (phMobile != "")
	{
		if (phoneNumbers != '')
			phoneNumbers += ', ';
		phoneNumbers += "M: " + phMobile;
	}
	return phoneNumbers;
}


function ucfirst(str)
{
	// matches PHP function
	// makes the first letter of str upper case
	if (str.length == 0)
		return '';
	if (str.length == 1)
		return str.toUpperCase();
	return (left(str, 1)).toUpperCase() + right(str, str.length - 1);
}


function ucwords(text)
{
	// Makes the first letter of each word uppercase.
	// A word is any string of characters after a whitespace character.
	var ch, prev_ch;
	var result = "";
	for (var i = 0; i < text.length; i++)
	{
		ch = text.charAt(i);
		if (i == 0 || isWhitespace(prev_ch))
			result += ch.toUpperCase();
		else
			result += ch;
		prev_ch = ch;
	}
	return result;
}


function getExtension(filename)
{
	var dotpos = filename.lastIndexOf(".");
	if (dotpos == -1)
		return "";
	return filename.substr(dotpos + 1);
}


function writeEmailLink(user, domain, link, class)
{
	document.write("<a href='mailto:" + user + "@" + domain + "'");
	if (class != null)
		document.write(" class='" + class + "'");
	document.write(">" + link + "</a>");
}


function attributeString(attribs)
{
	var result = "";
	if (typeof attribs == 'object')
	{
		for (var attrib in attribs)
		{
			if (attribs.hasOwnProperty(attrib))
			{
				var value = attribs[attrib];
				result += " " + attrib + "='" + htmlspecialchars(value, ENT_QUOTES) + "'";
			}
		}
	}
	return result;
}