* @version $Id: sfChoiceFormat.class.php 4340 2007-06-23 06:47:05Z fabien $
* @package symfony
* @subpackage i18n
*/
/**
* sfChoiceFormat class.
*
* sfChoiceFormat converts between ranges of numeric values and string
* names for those ranges.
*
* A sfChoiceFormat splits the real number line -Inf to +Inf into two or
* more contiguous ranges. Each range is mapped to a string.
* sfChoiceFormat is generally used in a MessageFormat for displaying
* grammatically correct plurals such as "There are 2 files."
*
*
* $string = '[0] are no files |[1] is one file |(1,Inf] are {number} files';
*
* $formatter = new sfMessageFormat(...); //init for a source
* $translated = $formatter->format($string);
*
* $choice = new sfChoiceFormat();
* echo $choice->format($translated, 0); //shows "are no files"
*
*
* The message/string choices are separated by the pipe "|" followed
* by a set notation of the form
* # [1,2] -- accepts values between 1 and 2, inclusive.
* # (1,2) -- accepts values between 1 and 2, excluding 1 and 2.
* # {1,2,3,4} -- only values defined in the set are accepted.
* # [-Inf,0) -- accepts value greater or equal to negative infinity
* and strictly less than 0
* Any non-empty combinations of the delimiters of square and round brackets
* are acceptable.
*
* @author Xiang Wei Zhuo
* @version v1.0, last update on Fri Dec 24 20:46:16 EST 2004
* @package System.I18N.core
*/
class sfChoiceFormat
{
/**
* The pattern to validate a set notation
*/
protected $validate = '/[\(\[\{]|[-Inf\d]+|,|[\+Inf\d]+|[\)\]\}]/ms';
/**
* The pattern to parse the formatting string.
*/
protected $parse = '/\s?\|?([\(\[\{]([-Inf\d]+,?[\+Inf\d]*)+[\)\]\}])\s?/';
/**
* The value for positive infinity.
*/
protected $inf;
/**
* Constructor.
*/
public function __construct()
{
$this->inf = -log(0);
}
/**
* Determines if the given number belongs to a given set
*
* @param float the number to test.
* @param string the set, in set notation.
* @return boolean true if number is in the set, false otherwise.
*/
public function isValid($number, $set)
{
$n = preg_match_all($this->validate, $set, $matches, PREG_SET_ORDER);
if ($n < 3)
{
$error = 'Invalid set "%s"';
$error = sprintf($error, $set);
throw new sfException($error);
}
$leftBracket = $matches[0][0];
$rightBracket = $matches[$n - 1][0];
$i = 0;
$elements = array();
foreach ($matches as $match)
{
$string = $match[0];
if ($i != 0 && $i != $n - 1 && $string !== ',')
{
if ($string == '-Inf')
{
$elements[] = -1 * $this->inf;
}
else if ($string == '+Inf' || $string == 'Inf')
{
$elements[] = $this->inf;
}
else
{
$elements[] = floatval($string);
}
}
$i++;
}
$total = count($elements);
$number = floatval($number);
if ($leftBracket == '{' && $rightBracket == '}')
{
return in_array($number, $elements);
}
$left = false;
if ($leftBracket == '[')
{
$left = $number >= $elements[0];
}
else if ($leftBracket == '(')
{
$left = $number > $elements[0];
}
$right = false;
if ($rightBracket==']')
{
$right = $number <= $elements[$total - 1];
}
else if ($rightBracket == ')')
{
$right = $number < $elements[$total - 1];
}
if ($left && $right)
{
return true;
}
return false;
}
/**
* Parses a choice string and get a list of sets and a list of strings corresponding to the sets.
*
* @param string the string containing the choices
* @return array array($sets, $strings)
*/
public function parse($string)
{
$n = preg_match_all($this->parse, $string, $matches, PREG_OFFSET_CAPTURE);
$sets = array();
foreach ($matches[1] as $match)
{
$sets[] = $match[0];
}
$offset = $matches[0];
$strings = array();
for ($i = 0; $i < $n; $i++)
{
$len = strlen($offset[$i][0]);
$begin = $i == 0 ? $len : $offset[$i][1] + $len;
$end = $i == $n - 1 ? strlen($string) : $offset[$i + 1][1];
$strings[] = substr($string, $begin, $end - $begin);
}
return array($sets, $strings);
}
/**
* For the choice string, and a number, find and return the string that satisfied the set within the choices.
*
* @param string the choices string.
* @param float the number to test.
* @return string the choosen string.
*/
public function format($string, $number)
{
list($sets, $strings) = $this->parse($string);
$total = count($sets);
for ($i = 0; $i < $total; $i++)
{
if ($this->isValid($number, $sets[$i]))
{
return $strings[$i];
}
}
return false;
}
}