1<?php
2
3use dokuwiki\Extension\ActionPlugin;
4use dokuwiki\Extension\Event;
5use dokuwiki\Extension\EventHandler;
6use dokuwiki\File\PageFile;
7
8/**
9 * DokuWiki Plugin renderrevisions (Action Component)
10 *
11 * @license GPL 2 http://www.gnu.org/licenses/gpl-2.0.html
12 * @author Andreas Gohr <dokuwiki@cosmocode.de>
13 */
14class action_plugin_renderrevisions extends ActionPlugin
15{
16    /** @var array list of pages that are processed by the plugin */
17    protected $pages = [];
18
19    /** @var string|null  the current page being saved, used to overwrite the contentchanged check */
20    protected $current = null;
21
22    /** @inheritDoc */
23    public function register(EventHandler $controller)
24    {
25        $controller->register_hook('PARSER_CACHE_USE', 'AFTER', $this, 'handleParserCacheUse');
26
27        $controller->register_hook(
28            'RENDERER_CONTENT_POSTPROCESS',
29            'AFTER',
30            $this,
31            'handleRenderContent',
32            null,
33            PHP_INT_MAX // other plugins might want to change the content before we see it
34        );
35
36        $controller->register_hook('COMMON_WIKIPAGE_SAVE', 'BEFORE', $this, 'handleCommonWikipageSave');
37    }
38
39    /**
40     * Event handler for PARSER_CACHE_USE
41     *
42     * @see https://www.dokuwiki.org/devel:event:PARSER_CACHE_USE
43     * @param Event $event Event object
44     * @param mixed $param optional parameter passed when event was registered
45     * @return void
46     */
47    public function handleParserCacheUse(Event $event, $param)
48    {
49        $cacheObject = $event->data;
50
51        if (!$cacheObject->page) return;
52        if ($cacheObject->mode !== 'xhtml') return;
53
54        // only process pages that match both the skip and match regex
55
56        $page = $cacheObject->page;
57        try {
58            [$skipRE, $matchRE] = $this->getRegexps();
59        } catch (\Exception $e) {
60            msg(hsc($e->getMessage()), -1);
61            return;
62        }
63        if (
64            ($skipRE && preg_match($skipRE, ":$page")) ||
65            ($matchRE && !preg_match($matchRE, ":$page"))
66        ) {
67            return;
68        }
69
70        // remember that this page was processed
71        // This is a somewhat ugly workaround for when text snippets are rendered within the same page.
72        // Those snippets will not have a page context set during cache use event and thus not be processed
73        // later on in the RENDERER_CONTENT_POSTPROCESS event
74        $this->pages[$page] = true;
75    }
76
77
78    /**
79     * Event handler for RENDERER_CONTENT_POSTPROCESS
80     *
81     * @see https://www.dokuwiki.org/devel:event:RENDERER_CONTENT_POSTPROCESS
82     * @param Event $event Event object
83     * @param mixed $param optional parameter passed when event was registered
84     * @return void
85     */
86    public function handleRenderContent(Event $event, $param)
87    {
88        [$format, $xhtml] = $event->data;
89        if ($format !== 'xhtml') return;
90
91        // thanks to the $this->pages property we might be able to skip some of those checks, but they don't hurt
92        global $ACT;
93        global $REV;
94        global $DATE_AT;
95        global $ID;
96        global $INFO;
97        if ($ACT !== 'show') return;
98        if ($REV) return;
99        if ($DATE_AT) return;
100        if (!$INFO['exists']) return;
101        if (!$ID) return;
102        if (!isset($this->pages[$ID])) return;
103
104        $md5cache = getCacheName($ID, '.renderrevision');
105
106        // no or outdated MD5 cache, create new one
107        // this means a new revision of the page has been created naturally
108        // we store the new render result and are done
109        if (!file_exists($md5cache) || filemtime(wikiFN($ID)) > filemtime($md5cache)) {
110            file_put_contents($md5cache, md5($xhtml));
111            return;
112        }
113
114        // only act on pages that have not been changed very recently
115        if (time() - filemtime(wikiFN($ID)) < $this->getConf('maxfrequency')) {
116            return;
117        }
118
119        // get the render result as it were when the page was last changed
120        $oldMd5 = file_get_contents($md5cache);
121
122        // did the rendered content change?
123        if ($oldMd5 === md5($xhtml)) {
124            return;
125        }
126
127        // time to create a new revision
128        $this->current = $ID;
129        (new PageFile($ID))->saveWikiText(rawWiki($ID), $this->getLang('summary'));
130        $this->current = null;
131    }
132
133    /**
134     * Event handler for COMMON_WIKIPAGE_SAVE
135     *
136     * Overwrite the contentChanged flag to force a new revision even though the content did not change
137     *
138     * @see https://www.dokuwiki.org/devel:event:COMMON_WIKIPAGE_SAVE
139     * @param Event $event Event object
140     * @param mixed $param optional parameter passed when event was registered
141     * @return void
142     */
143    public function handleCommonWikipageSave(Event $event, $param)
144    {
145        if ($this->current !== $event->data['id']) return;
146        $event->data['contentChanged'] = true;
147    }
148
149
150    /**
151     * Read the skip and match regex from the config
152     *
153     * Ensures the regular expressions are valid
154     *
155     * @return string[] [$skipRE, $matchRE]
156     * @throws \Exception if the regular expressions are invalid
157     */
158    public function getRegexps()
159    {
160        $skip = $this->getConf('skipRegex');
161        $skipRE = '';
162        $match = $this->getConf('matchRegex');
163        $matchRE = '';
164
165        if ($skip) {
166            $skipRE = '/' . $skip . '/';
167            if (@preg_match($skipRE, '') === false) {
168                throw new \Exception('Invalid regular expression in $conf[\'skipRegex\']. ' . preg_last_error_msg());
169            }
170        }
171
172        if ($match) {
173            $matchRE = '/' . $match . '/';
174            if (@preg_match($matchRE, '') === false) {
175                throw new \Exception('Invalid regular expression in $conf[\'matchRegex\']. ' . preg_last_error_msg());
176            }
177        }
178        return [$skipRE, $matchRE];
179    }
180}
181