1<?php
2
3/**
4 * Hoa
5 *
6 *
7 * @license
8 *
9 * New BSD License
10 *
11 * Copyright © 2007-2017, Hoa community. All rights reserved.
12 *
13 * Redistribution and use in source and binary forms, with or without
14 * modification, are permitted provided that the following conditions are met:
15 *     * Redistributions of source code must retain the above copyright
16 *       notice, this list of conditions and the following disclaimer.
17 *     * Redistributions in binary form must reproduce the above copyright
18 *       notice, this list of conditions and the following disclaimer in the
19 *       documentation and/or other materials provided with the distribution.
20 *     * Neither the name of the Hoa nor the names of its contributors may be
21 *       used to endorse or promote products derived from this software without
22 *       specific prior written permission.
23 *
24 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
25 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS AND CONTRIBUTORS BE
28 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
29 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
30 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
31 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
32 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
33 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
34 * POSSIBILITY OF SUCH DAMAGE.
35 */
36
37namespace Hoa\Iterator;
38
39/**
40 * Class \Hoa\Iterator\Lookbehind.
41 *
42 * Look behind iterator.
43 *
44 * @copyright  Copyright © 2007-2017 Hoa community
45 * @license    New BSD License
46 */
47class Lookbehind extends IteratorIterator implements Outer
48{
49    /**
50     * Current iterator.
51     *
52     * @var \Iterator
53     */
54    protected $_iterator        = null;
55
56    /**
57     * Previous key.
58     *
59     * @var mixed
60     */
61    protected $_previousKey     = -1;
62
63    /**
64     * Previous value.
65     *
66     * @var mixed
67     */
68    protected $_previousCurrent = null;
69
70
71
72    /**
73     * Construct.
74     *
75     * @param   \Iterator  $iterator    Iterator.
76     */
77    public function __construct(\Iterator $iterator)
78    {
79        $this->_iterator = $iterator;
80
81        return;
82    }
83
84    /**
85     * Get inner iterator.
86     *
87     * @return  \Iterator
88     */
89    public function getInnerIterator()
90    {
91        return $this->_iterator;
92    }
93
94    /**
95     * Return the current element.
96     *
97     * @return  mixed
98     */
99    public function current()
100    {
101        return $this->getInnerIterator()->current();
102    }
103
104    /**
105     * Return the key of the current element.
106     *
107     * @return  mixed
108     */
109    public function key()
110    {
111        return $this->getInnerIterator()->key();
112    }
113
114    /**
115     * Move forward to next element.
116     *
117     * @return  void
118     */
119    public function next()
120    {
121        $this->_previousKey     = $this->key();
122        $this->_previousCurrent = $this->current();
123
124        return $this->getInnerIterator()->next();
125    }
126
127    /**
128     * Rewind the iterator to the first element.
129     *
130     * @return  void
131     */
132    public function rewind()
133    {
134        $this->_previousKey     = -1;
135        $this->_previousCurrent = null;
136
137        return $this->getInnerIterator()->rewind();
138    }
139
140    /**
141     * Check if current position is valid.
142     *
143     * @return  bool
144     */
145    public function valid()
146    {
147        return $this->getInnerIterator()->valid();
148    }
149
150    /**
151     * Check whether there is a previous element.
152     *
153     * @return  bool
154     */
155    public function hasPrevious()
156    {
157        return -1 !== $this->_previousKey;
158    }
159
160    /**
161     * Get previous value.
162     *
163     * @return  mixed
164     */
165    public function getPrevious()
166    {
167        return $this->_previousCurrent;
168    }
169
170    /**
171     * Get previous key.
172     *
173     * @return  mixed
174     */
175    public function getPreviousKey()
176    {
177        return $this->_previousKey;
178    }
179}
180