Refactor Linker class, add Target class.

includes/Target.php

@@ -0,0 +1,200 @@
+<?php
+/**
+ * The LinkTitles\Target represents a Wiki page that is a potential link target.
+ *
+ * Copyright 2012-2017 Daniel Kraus <bovender@bovender.de> ('bovender')
+ *
+ * This program 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 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program 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 this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
+ * MA 02110-1301, USA.
+ *
+ * @author Daniel Kraus <bovender@bovender.de>
+ */
+namespace LinkTitles;
+
+/**
+ * Represents a page that is a potential link target.
+ */
+class Target {
+	/**
+	 * \TitleValue object for the current target page title.
+	 * @var \TitleValue $titleValue;
+	 */
+	public $titleValue;
+
+	/**
+	 * Regex that matches the start of a word; this expression depends on the
+	 * setting of LinkTitles\Config->wordStartOnly;
+	 * @var String $wordStart
+	 */
+	public $wordStart;
+
+	/**
+	 * Regex that matches the end of a word; this expression depends on the
+	 * setting of LinkTitles\Config->wordEndOnly;
+	 * @var String $wordEnd
+	 */
+	public $wordEnd;
+
+	/**
+	 * A Title object for the target page currently being examined.
+	 * @var \Title $title
+	 */
+	private $title;
+
+	/**
+	 * Caches the target page content as a \Content object.
+	 *
+	 * @var \Content $content
+	 */
+	private $content;
+
+	/**
+	 * LinkTitles configuration.
+	 * @var Config $config
+	 */
+	private $config;
+
+	/**
+	 * Constructs a new Target object
+	 *
+	 * The parameters may be taken from database rows, for example.
+	 *
+	 * @param Int $nameSpace Name space of the target page
+	 * @param String &$title Title of the target page
+	 */
+	public function __construct( $nameSpace, &$title, Config &$config ) {
+		$this->title = \Title::makeTitleSafe( $nameSpace, $title );
+		$this->titleValue = $this->title->getTitleValue();
+		$this->config = $config;
+
+		// Use unicode character properties rather than \b escape sequences
+		// to detect whole words containing non-ASCII characters as well.
+		// Note that this requires a PCRE library that was compiled with
+		// --enable-unicode-properties
+		( $config->wordStartOnly ) ? $this->wordStart = '(?<!\pL)' : $this->wordStart = '';
+		( $config->wordEndOnly ) ? $this->wordEnd = '(?!\pL)' : $this->wordEnd = '';
+	}
+
+	/**
+	 * Gets the string representation of the target title.
+	 * @return String title text
+	 */
+	public function getTitleText() {
+		return $this->title->getText();
+	}
+
+	/**
+	 * Gets the title string with certain characters escaped that may interfere
+	 * with regular expressions.
+	 * @return String representation of the title, regex-safe
+	 */
+	public function getRegexSafeTitle() {
+		return preg_quote( $this->title->getText(), '/' );
+	}
+
+	/**
+	 * Builds a regular expression of the title
+	 * @return String regular expression for this title.
+	 */
+	public function getCaseSensitiveRegex() {
+		$regexSafeTitle = $this->getRegexSafeTitle();
+
+		// Depending on the $config->capitalLinks setting,
+		// the title has to be searched for either in a strictly case-sensitive
+		// way, or in a 'fuzzy' way where the first letter of the title may
+		// be either case.
+		//
+		if ( $this->config->capitalLinks && ( $regexSafeTitle[0] != '\\' )) {
+			$searchTerm = '((?i)' . $regexSafeTitle[0] . '(?-i)' . substr($regexSafeTitle, 1) . ')';
+		}	else {
+			$searchTerm = '(' . $regexSafeTitle . ')';
+		}
+
+		return $this->buildRegex( $searchTerm );
+	}
+
+	/**
+	 * Builds a regular expression pattern for the title in a case-insensitive
+	 * way.
+	 * @return String case-insensitive regular expression pattern for the title
+	 */
+	public function getCaseInsensitiveRegex() {
+		return $this->buildRegex( $this->getRegexSafeTitle() ) . 'i';
+	}
+
+	/**
+	 * Builds the basic regex that is used to match target page titles in a source
+	 * text.
+	 * @param  String $searchTerm Target page title (special characters must be quoted)
+	 * @return String regular expression pattern
+	 */
+	private function buildRegex( $searchTerm ) {
+		return '/(?<![\:\.\@\/\?\&])' . $this->wordStart . $searchTerm . $this->wordEnd . '/S';
+	}
+
+	/**
+	 * Returns the \Content of the target page.
+	 *
+	 * The value is cached.
+	 * @return \Content Content of the Target page.
+	 */
+	public function getContent() {
+		if ( $this->content === null ) {
+			$this->content = \WikiPage::factory( $this->title )->getContent();
+		};
+		return $this->content;
+	}
+
+	/**
+	 * Examines the current target page. Returns true if it may be linked;
+	 * false if not. This depends on two settings:
+	 * $wgLinkTitlesCheckRedirect and $wgLinkTitlesEnableNoTargetMagicWord
+	 * and whether the target page is a redirect or contains the
+	 * __NOAUTOLINKTARGET__ magic word.
+	 *
+	 * @param \Title $fromTitle
+	 *
+	 * @return boolean
+	 */
+	public function mayLinkTo( \Title $fromTitle ) {
+		// If checking for redirects is enabled and the target page does
+		// indeed redirect to the current page, return the page title as-is
+		// (unlinked).
+		if ( $this->config->checkRedirect ) {
+			$redirectTitle = $this->getContent()->getUltimateRedirectTarget();
+			if ( $redirectTitle && $redirectTitle->equals( $fromtitle ) ) {
+				return false;
+			}
+		};
+		// If the magic word __NOAUTOLINKTARGET__ is enabled and the target
+		// page does indeed contain this magic word, return the page title
+		// as-is (unlinked).
+		if ( $this->config->enableNoTargetMagicWord ) {
+			if ( $this->getContent()->matchMagicWord( \MagicWord::get('MAG_LINKTITLES_NOTARGET') ) ) {
+				return false;
+			}
+		};
+		return true;
+	}
+
+	/**
+	 * Determines if the Target's title is the same as another title.
+	 * @param  Title   $otherTitle Other title
+	 * @return boolean             True if the $otherTitle is the same, false if not.
+	 */
+	public function isSameTitle( \Title $otherTitle) {
+		return $this->title->equals( $otherTitle );
+	}
+}