<?php
/**
 * Numbers_Words
 *
 * PHP version 4
 *
 * Copyright (c) 1997-2006 The PHP Group
 *
 * This source file is subject to version 3.0 of the PHP license,
 * that is bundled with this package in the file LICENSE, and is
 * available at through the world-wide-web at
 * http://www.php.net/license/3_0.txt.
 * If you did not receive a copy of the PHP license and are unable to
 * obtain it through the world-wide-web, please send a note to
 * license@php.net so we can mail you a copy immediately.
 *
 * @category Numbers
 * @package  Numbers_Words
 * @author   Piotr Klaban <makler@man.torun.pl>
 * @license  PHP 3.0 http://www.php.net/license/3_0.txt
 * @version  SVN: $Id: lang.en_100.php 302816 2010-08-26 16:02:29Z ifeghali $
 * @link     http://pear.php.net/package/Numbers_Words
 */

/**
 * Class for translating numbers into Donald Knuth system, in English language.
 *
 * @author Piotr Klaban
 * @package Numbers_Words
 */

/**
 * Include needed files
 */
require_once "Numbers/Words.php";

/**
 * Class for translating numbers into Donald Knuth system, in English language.
 *
 * @category Numbers
 * @package  Numbers_Words
 * @author   Piotr Klaban <makler@man.torun.pl>
 * @license  PHP 3.0 http://www.php.net/license/3_0.txt
 * @link     http://pear.php.net/package/Numbers_Words
 */
class Numbers_Words_en_100 extends Numbers_Words
{

	// {{{ properties

	/**
	 * Locale name
	 * @var string
	 * @access public
	 */
	var $locale = 'en_100';

	/**
	 * Language name in English
	 * @var string
	 * @access public
	 */
	var $lang = 'English (Donald Knuth system)';

	/**
	 * Native language name
	 * @var string
	 * @access public
	 */
	var $lang_native = 'English (Donald Knuth system)';

	/**
	 * The word for the minus sign
	 * @var string
	 * @access private
	 */
	var $_minus = 'minus'; // minus sign

	/**
	 * The sufixes for exponents (singular and plural)
	 * Names based on:
	 * http://home.earthlink.net/~mrob/pub/math/largenum.html
	 * Donald Knuth system (power of 2)
	 * @var array
	 * @access private
	 */
	var $_exponent = array(
		0 => array(''),
		2 => array('hundred'),
		4 => array('myriad'),
		8 => array('myllion'),
	   16 => array('byllion'),
	   32 => array('tryllion'),
	   64 => array('quadryllion'),
	  128 => array('quintyllion'),
	  256 => array('sextyllion'),
	  512 => array('septyllion'),
	 1024 => array('octyllion'),
	 2048 => array('nonyllion'),
	 4096 => array('decyllion'),
	 8192 => array('undecyllion'),
	16384 => array('duodecyllion'),
	32768 => array('tredecyllion'),
	65536 => array('quattuordecyllion'),
	131072 => array('quindecyllion'),
	262144 => array('sexdecyllion'),
	524288 => array('septendecyllion'),
	1048576 => array('octodecyllion'),
	2097152 => array('novemdecyllion'),
	4194304 => array('vigintyllion')
		);

	/**
	 * The array containing the digits (indexed by the digits themselves).
	 * @var array
	 * @access private
	 */
	var $_digits = array(
		0 => 'zero', 'one', 'two', 'three', 'four',
		'five', 'six', 'seven', 'eight', 'nine'
	);

	/**
	 * The word separator
	 * @var string
	 * @access private
	 */
	var $_sep = ' ';
	// }}}
	// {{{ _toWords()

	/**
	 * Converts a number to its word representation
	 * in Donald Knuth system, in English language.
	 *
	 * @param integer $num       An integer between -infinity and infinity inclusive :)
	 *                           that need to be converted to words
	 * @param integer $power     The power of ten for the rest of the number to the right.
	 *                           Optional, defaults to 0.
	 * @param integer $powsuffix The power name to be added to the end of the return string.
	 *                           Used internally. Optional, defaults to ''.
	 *
	 * @return string  The corresponding word representation
	 *
	 * @access protected
	 * @author Piotr Klaban <makler@man.torun.pl>
	 * @since  Numbers_Words 0.16.3
	 */
	function _toWords($num, $power = 0, $powsuffix = '')
	{
		$ret = '';

		// add a minus sign
		if (substr($num, 0, 1) == '-') {
			$ret = $this->_sep . $this->_minus;
			$num = substr($num, 1);
		}

		// strip excessive zero signs and spaces
		$num = trim($num);
		$num = preg_replace('/^0+/', '', $num);

		if (strlen($num) > 3) {
			$maxp = strlen($num)-1;
			$curp = $maxp;
			for ($p = $maxp; $p > 0; --$p) { // power
				// check for highest power
				if (isset($this->_exponent[$p])) {
					// send substr from $curp to $p
					$snum = substr($num, $maxp - $curp, $curp - $p + 1);
					$snum = preg_replace('/^0+/', '', $snum);
					if ($snum !== '') {
						$cursuffix = $this->_exponent[$power][count($this->_exponent[$power])-1];
						if ($powsuffix != '') {
							$cursuffix .= $this->_sep . $powsuffix;
						}

						$ret .= $this->_toWords($snum, $p, $cursuffix);
					}
					$curp = $p - 1;
					continue;
				}
			}
			$num = substr($num, $maxp - $curp, $curp - $p + 1);
			if ($num == 0) {
				return $ret;
			}
		} elseif ($num == 0 || $num == '') {
			return $this->_sep . $this->_digits[0];
		}

		$h = $t = $d = 0;

		switch (strlen($num)) {
			case 3:
				$h = (int) substr($num, -3, 1);

			case 2:
				$t = (int) substr($num, -2, 1);

			case 1:
				$d = (int) substr($num, -1, 1);
			break;

			case 0:
			return;
			break;
		}

		if ($h) {
			$ret .= $this->_sep . $this->_digits[$h] . $this->_sep . 'hundred';

			// in English only - add ' and' for [1-9]01..[1-9]99
			// (also for 1001..1099, 10001..10099 but it is harder)
			// for now it is switched off, maybe some language purists
			// can force me to enable it, or to remove it completely
			// if (($t + $d) > 0)
			//   $ret .= $this->_sep . 'and';
		}

		// ten, twenty etc.
		switch ($t) {
			case 9:
			case 7:
			case 6:
				$ret .= $this->_sep . $this->_digits[$t] . 'ty';
			break;

			case 8:
				$ret .= $this->_sep . 'eighty';
			break;

			case 5:
				$ret .= $this->_sep . 'fifty';
			break;

			case 4:
				$ret .= $this->_sep . 'forty';
			break;

			case 3:
				$ret .= $this->_sep . 'thirty';
			break;

			case 2:
				$ret .= $this->_sep . 'twenty';
			break;

			case 1:
				switch ($d) {
					case 0:
						$ret .= $this->_sep . 'ten';
					break;

					case 1:
						$ret .= $this->_sep . 'eleven';
					break;

					case 2:
						$ret .= $this->_sep . 'twelve';
					break;

					case 3:
						$ret .= $this->_sep . 'thirteen';
					break;

					case 4:
					case 6:
					case 7:
					case 9:
						$ret .= $this->_sep . $this->_digits[$d] . 'teen';
					break;

					case 5:
						$ret .= $this->_sep . 'fifteen';
					break;

					case 8:
						$ret .= $this->_sep . 'eighteen';
					break;
				}
			break;
		}

		if ($t != 1 && $d > 0) { // add digits only in <0>,<1,9> and <21,inf>
			// add minus sign between [2-9] and digit
			if ($t > 1) {
				$ret .= '-' . $this->_digits[$d];
			} else {
				$ret .= $this->_sep . $this->_digits[$d];
			}
		}

		if ($power > 0) {
			if (isset($this->_exponent[$power])) {
				$lev = $this->_exponent[$power];
			}

			if (!isset($lev) || !is_array($lev)) {
				return null;
			}

			$ret .= $this->_sep . $lev[0];
		}

		if ($powsuffix != '') {
			$ret .= $this->_sep . $powsuffix;
		}

		return $ret;
	}
	// }}}
}
