TextWrapper.php

<?php
/*
    This file is part of Erebot, a modular IRC bot written in PHP.

    Copyright © 2010 François Poirotte

    Erebot is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.

    Erebot is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with Erebot.  If not, see <http://www.gnu.org/licenses/>.
*/

namespace Erebot;

class TextWrapper implements \Erebot\Interfaces\TextWrapper
{
    protected $text;

    protected $position;

    public function __construct($text)
    {
        $this->text        = $text;
        $this->position    = 0;
    }

    public function getTokens($start, $length = 0, $separator = ' ')
    {
        $string = preg_replace('/\\s+/', ' ', trim($this->text, $separator));
        $parts  = explode($separator, $string);

        if (!$length) {
            $parts = array_slice($parts, $start);
        } else {
            $parts = array_slice($parts, $start, $length);
        }

        if (!count($parts)) {
            return "";
        }

        return implode($separator, $parts);
    }

    public function countTokens($separator = ' ')
    {
        $string = preg_replace('/\\s+/', ' ', trim($this->text, $separator));
        return count(explode($separator, $string));
    }

    public function __toString()
    {
        return $this->text;
    }

    public function count()
    {
        return $this->countTokens();
    }

    public function current()
    {
        return $this->getTokens($this->position, 1);
    }

    public function key()
    {
        return $this->position;
    }

    public function next()
    {
        $this->position++;
    }

    public function rewind()
    {
        $this->position = 0;
    }

    public function valid()
    {
        return ($this->position < $this->countTokens());
    }

    public function offsetExists($offset)
    {
        return (
            is_int($offset) &&
            $offset >= 0 &&
            $offset < $this->countTokens()
        );
    }

    public function offsetGet($offset)
    {
        if (!is_int($offset)) {
            return null;
        }
        return $this->getTokens($offset, 1);
    }

    public function offsetSet($offset, $value)
    {
        throw new \RuntimeException('The wrapped text is read-only');
    }

    public function offsetUnset($offset)
    {
        throw new \RuntimeException('The wrapped text is read-only');
    }
}