aboutsummaryrefslogtreecommitdiffhomepage
path: root/plugins/markdown/markdown.php
blob: 6b1c1d4433b8be80c32b7fc981e0effa97637661 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
<?php

/**
 * Plugin Markdown.
 *
 * Shaare's descriptions are parsed with Markdown.
 */

require_once 'Parsedown.php';

/*
 * If this tag is used on a shaare, the description won't be processed by Parsedown.
 */
define('NO_MD_TAG', 'nomarkdown');

/**
 * Parse linklist descriptions.
 *
 * @param array $data linklist data.
 *
 * @return mixed linklist data parsed in markdown (and converted to HTML).
 */
function hook_markdown_render_linklist($data)
{
    foreach ($data['links'] as &$value) {
        if (!empty($value['tags']) && noMarkdownTag($value['tags'])) {
            $value['taglist'] = stripNoMarkdownTag($value['taglist']);
            continue;
        }
        $value['description'] = process_markdown($value['description']);
    }
    return $data;
}

/**
 * Parse feed linklist descriptions.
 *
 * @param array $data linklist data.
 *
 * @return mixed linklist data parsed in markdown (and converted to HTML).
 */
function hook_markdown_render_feed($data)
{
    foreach ($data['links'] as &$value) {
        if (!empty($value['tags']) && noMarkdownTag($value['tags'])) {
            $value['tags'] = stripNoMarkdownTag($value['tags']);
            continue;
        }
        $value['description'] = process_markdown($value['description']);
    }

    return $data;
}

/**
 * Parse daily descriptions.
 *
 * @param array $data daily data.
 *
 * @return mixed daily data parsed in markdown (and converted to HTML).
 */
function hook_markdown_render_daily($data)
{
    // Manipulate columns data
    foreach ($data['cols'] as &$value) {
        foreach ($value as &$value2) {
            if (!empty($value2['tags']) && noMarkdownTag($value2['tags'])) {
                continue;
            }
            $value2['formatedDescription'] = process_markdown($value2['formatedDescription']);
        }
    }

    return $data;
}

/**
 * Check if noMarkdown is set in tags.
 *
 * @param string $tags tag list
 *
 * @return bool true if markdown should be disabled on this link.
 */
function noMarkdownTag($tags)
{
    return strpos($tags, NO_MD_TAG) !== false;
}

/**
 * Remove the no-markdown meta tag so it won't be displayed.
 *
 * @param string $tags Tag list.
 *
 * @return string tag list without no markdown tag.
 */
function stripNoMarkdownTag($tags)
{
    unset($tags[array_search(NO_MD_TAG, $tags)]);
    return array_values($tags);
}

/**
 * When link list is displayed, include markdown CSS.
 *
 * @param array $data includes data.
 *
 * @return mixed - includes data with markdown CSS file added.
 */
function hook_markdown_render_includes($data)
{
    if ($data['_PAGE_'] == Router::$PAGE_LINKLIST
        || $data['_PAGE_'] == Router::$PAGE_DAILY
        || $data['_PAGE_'] == Router::$PAGE_EDITLINK
    ) {
        
        $data['css_files'][] = PluginManager::$PLUGINS_PATH . '/markdown/markdown.css';
    }

    return $data;
}

/**
 * Hook render_editlink.
 * Adds an help link to markdown syntax.
 *
 * @param array $data data passed to plugin
 *
 * @return array altered $data.
 */
function hook_markdown_render_editlink($data)
{
    // Load help HTML into a string
    $data['edit_link_plugin'][] = file_get_contents(PluginManager::$PLUGINS_PATH .'/markdown/help.html');

    // Add no markdown 'meta-tag' in tag list if it was never used, for autocompletion.
    if (! in_array(NO_MD_TAG, $data['tags'])) {
        $data['tags'][NO_MD_TAG] = 0;
    }

    return $data;
}


/**
 * Remove HTML links auto generated by Shaarli core system.
 * Keeps HREF attributes.
 *
 * @param string $description input description text.
 *
 * @return string $description without HTML links.
 */
function reverse_text2clickable($description)
{
    $descriptionLines = explode(PHP_EOL, $description);
    $descriptionOut = '';
    $codeBlockOn = false;
    $lineCount = 0;

    foreach ($descriptionLines as $descriptionLine) {
        // Detect line of code
        $codeLineOn = preg_match('/^    /', $descriptionLine) > 0;
        // Detect and toggle block of code
        if (!$codeBlockOn) {
            $codeBlockOn = preg_match('/^```/', $descriptionLine) > 0;
        }
        elseif (preg_match('/^```/', $descriptionLine) > 0) {
            $codeBlockOn = false;
        }

        $hashtagTitle = ' title="Hashtag [^"]+"';
        // Reverse `inline code` hashtags.
        $descriptionLine = preg_replace(
            '!(`[^`\n]*)<a href="[^ ]*"'. $hashtagTitle .'>([^<]+)</a>([^`\n]*`)!m',
            '$1$2$3',
            $descriptionLine
        );

        // Reverse hashtag links if we're in a code block.
        $hashtagFilter = ($codeBlockOn || $codeLineOn) ? $hashtagTitle : '';
        $descriptionLine = preg_replace(
            '!<a href="[^ ]*"'. $hashtagFilter .'>([^<]+)</a>!m',
            '$1',
            $descriptionLine
        );

        $descriptionOut .= $descriptionLine;
        if ($lineCount++ < count($descriptionLines) - 1) {
            $descriptionOut .= PHP_EOL;
        }
    }
    return $descriptionOut;
}

/**
 * Remove <br> tag to let markdown handle it.
 *
 * @param string $description input description text.
 *
 * @return string $description without <br> tags.
 */
function reverse_nl2br($description)
{
    return preg_replace('!<br */?>!im', '', $description);
}

/**
 * Remove HTML spaces '&nbsp;' auto generated by Shaarli core system.
 *
 * @param string $description input description text.
 *
 * @return string $description without HTML links.
 */
function reverse_space2nbsp($description)
{
    return preg_replace('/(^| )&nbsp;/m', '$1 ', $description);
}

/**
 * Remove dangerous HTML tags (tags, iframe, etc.).
 * Doesn't affect <code> content (already escaped by Parsedown).
 *
 * @param string $description input description text.
 *
 * @return string given string escaped.
 */
function sanitize_html($description)
{
    $escapeTags = array(
        'script',
        'style',
        'link',
        'iframe',
        'frameset',
        'frame',
    );
    foreach ($escapeTags as $tag) {
        $description = preg_replace_callback(
            '#<\s*'. $tag .'[^>]*>(.*</\s*'. $tag .'[^>]*>)?#is',
            function ($match) { return escape($match[0]); },
            $description);
    }
    $description = preg_replace(
        '#(<[^>]+)on[a-z]*="[^"]*"#is',
        '$1',
        $description);
    return $description;
}

/**
 * Render shaare contents through Markdown parser.
 *   1. Remove HTML generated by Shaarli core.
 *   2. Reverse the escape function.
 *   3. Generate markdown descriptions.
 *   4. Sanitize sensible HTML tags for security.
 *   5. Wrap description in 'markdown' CSS class.
 *
 * @param string $description input description text.
 *
 * @return string HTML processed $description.
 */
function process_markdown($description)
{
    $parsedown = new Parsedown();

    $processedDescription = $description;
    $processedDescription = reverse_nl2br($processedDescription);
    $processedDescription = reverse_space2nbsp($processedDescription);
    $processedDescription = reverse_text2clickable($processedDescription);
    $processedDescription = unescape($processedDescription);
    $processedDescription = $parsedown
        ->setMarkupEscaped(false)
        ->setBreaksEnabled(true)
        ->text($processedDescription);
    $processedDescription = sanitize_html($processedDescription);

    if(!empty($processedDescription)){
        $processedDescription = '<div class="markdown">'. $processedDescription . '</div>';
    }

    return $processedDescription;
}