1<?php
2/**
3 * Copyright © 2000, 2001 Geoffrey T. Dairiki <dairiki@dairiki.org>
4 * You may copy this code freely under the conditions of the GPL.
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License along
17 * with this program; if not, write to the Free Software Foundation, Inc.,
18 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
19 * http://www.gnu.org/copyleft/gpl.html
20 *
21 * @file
22 * @ingroup DifferenceEngine
23 * @defgroup DifferenceEngine DifferenceEngine
24 */
25
26namespace MediaWiki\Diff;
27
28/**
29 * Stores, escapes and formats the results of word-level diff
30 *
31 * @internal
32 * @ingroup DifferenceEngine
33 */
34class WordAccumulator {
35	public $insClass = ' class="diffchange diffchange-inline"';
36	public $delClass = ' class="diffchange diffchange-inline"';
37
38	private $lines = [];
39	private $line = '';
40	private $group = '';
41	private $tag = '';
42
43	/**
44	 * @param string $new_tag
45	 */
46	private function flushGroup( $new_tag ) {
47		if ( $this->group !== '' ) {
48			if ( $this->tag == 'ins' ) {
49				$this->line .= "<ins{$this->insClass}>" . htmlspecialchars( $this->group ) . '</ins>';
50			} elseif ( $this->tag == 'del' ) {
51				$this->line .= "<del{$this->delClass}>" . htmlspecialchars( $this->group ) . '</del>';
52			} else {
53				$this->line .= htmlspecialchars( $this->group );
54			}
55		}
56		$this->group = '';
57		$this->tag = $new_tag;
58	}
59
60	/**
61	 * @param string $new_tag
62	 */
63	private function flushLine( $new_tag ) {
64		$this->flushGroup( $new_tag );
65		if ( $this->line != '' ) {
66			array_push( $this->lines, $this->line );
67		} else {
68			# make empty lines visible by inserting an NBSP
69			array_push( $this->lines, "\u{00A0}" );
70		}
71		$this->line = '';
72	}
73
74	/**
75	 * @param string[] $words
76	 * @param string $tag
77	 */
78	public function addWords( $words, $tag = '' ) {
79		if ( $tag != $this->tag ) {
80			$this->flushGroup( $tag );
81		}
82
83		foreach ( $words as $word ) {
84			// new-line should only come as first char of word.
85			if ( $word == '' ) {
86				continue;
87			}
88			if ( $word[0] == "\n" ) {
89				$this->flushLine( $tag );
90				$word = substr( $word, 1 );
91			}
92			// FIXME: Don't use assert()
93			// phpcs:ignore MediaWiki.Usage.ForbiddenFunctions.assert
94			assert( !strstr( $word, "\n" ) );
95			$this->group .= $word;
96		}
97	}
98
99	/**
100	 * @return string[]
101	 */
102	public function getLines() {
103		$this->flushLine( '~done' );
104
105		return $this->lines;
106	}
107}
108