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Diffstat (limited to 'mod/linkup/start.php')
| -rw-r--r-- | mod/linkup/start.php | 413 |
1 files changed, 413 insertions, 0 deletions
diff --git a/mod/linkup/start.php b/mod/linkup/start.php new file mode 100644 index 000000000..05e4bdb66 --- /dev/null +++ b/mod/linkup/start.php @@ -0,0 +1,413 @@ +<?php +/** + * Linkup -- Simple markup to link entities across applications. + * + * It recognizes: @username, !group-alias, !group-guid, #task-guid, #hashtag, + * and *entity-guid. + * + * @package Lorea + * @subpackage Linkup + * @homepage http://lorea.org/plugin/linkup + * @copyright 2012,2013 Lorea Faeries <federation@lorea.org> + * @license COPYING, http://www.gnu.org/licenses/agpl + * + * Copyright 2012-2013 Lorea Faeries <federation@lorea.org> + * + * This program is free software: you can redistribute it and/or + * modify it under the terms of the GNU Affero General Public License + * as published by the Free Software Foundation, either version 3 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 + * Affero General Public License for more details. + * + * You should have received a copy of the GNU Affero General Public + * License along with this program. If not, see + * <http://www.gnu.org/licenses/>. + */ + +elgg_register_event_handler('init', 'system', 'linkup_init'); + +function linkup_init() { + // Register tests + elgg_register_plugin_hook_handler('unit_test', 'system', 'linkup_test'); + + // Register CSS + elgg_extend_view('css.elgg', 'linkup/css'); + + // Register hook + elgg_register_plugin_hook_handler('output:before', 'layout', 'linkup_event_handler'); + + // Extend CSS + elgg_extend_view('css/elgg', 'linkup/css'); +} + +/** + * @todo I'm ashamed + */ +function linkup_test($hook, $type, $value, $params) { + // $value[] = elgg_get_config('pluginspath') . "linkup/tests/linkup_test.php"; + return $value; +} + +/** + * Markup function + * + * Detect linkup patterns and make links where needed. + * + * Matches a marker character followed by printable characters, and + * prefixed to avoid matching CSS DOM IDs. First match is the prefix, + * second the marker, and third is the subject. + */ +function linkup_event_handler($hook, $type, $returnvalue, $params) { + + if (elgg_get_viewtype() != 'default') { + // only mess with html views + return $returnvalue; + } + $html = mb_convert_encoding($returnvalue['content'], 'HTML-ENTITIES', 'UTF-8'); + + if (empty($html)) { + return $returnvalue; + } + + libxml_use_internal_errors(TRUE); + + try { + + $dom = new DOMDocument(); + $dom->loadHTML($html); + + foreach ($dom->childNodes AS $node) { + + linkup_dom_recurse($node, 'linkup_dom_replace'); + + } + + // Remove tags added by DOMDocument + $matches = array('/^\<\!DOCTYPE.*?<html[^>]*><body[^>]*>/isu', + '|</body></html>$|isu'); + + $content = preg_replace($matches, '', $dom->saveHTML()); + + // convert back to original encoding + $returnvalue['content'] = mb_convert_encoding($content, 'UTF-8', 'HTML-ENTITIES'); + + } catch (Exception $e) { + + error_log("===== linkup error $e->class $e->message"); + + } + + return $returnvalue; + +} + +/** + * Utility to traverse a DOMDocument and execute a callback function + * on all children. + * + * @param $root a DOMNode + * @param $callback a function + * @return void + */ +function linkup_dom_recurse($root, $callback) { + + if ($root->hasChildNodes()) { + + foreach ($root->childNodes AS $node) { + + linkup_dom_recurse($node, $callback); + + } + + } else { + + if (is_callable($callback)) { + + $callback($root); + + } + } + +} + +/** + * linkup marking callback will markup only a safe set of conditions: + * + * - only TextNodes will be affected + * - only if their parent is not an attribute (e.g., title, href) + * - only if the parent tag can contain an A tag + * + * @internal + * @see linkup_skip_tags() + */ +function linkup_dom_replace($node) { + + if ($node->nodeType == XML_TEXT_NODE + && $node->parentNode->nodeType != XML_ATTRIBUTE_NODE + && !in_array($node->parentNode->tagName, linkup_skip_tags())) { + + $html = linkup_regexp($node->nodeValue); + + if (!empty($html) && $node->nodeValue != $html) { + + // Get what's inside the formatted <body> node from a new DOMDocument + $fix = new DOMDocument(); + $fix->loadHTML(trim($html)); + // get <body>(.*)</body> + $fix = $fix->documentElement->firstChild; + + if (!is_null($fix)) { + $parent = $node->parentNode; + $new_node = $parent->ownerDocument->importNode($fix, TRUE); + $parent->replaceChild($new_node, $node); + } + + } + + } + +} + +/** + * linkup_regexp -- markup text with HTML links + * + * This function expects plain text with a specific markup. + * It is called internally by the event handler to execute on selected + * strings: that means, do not try it on any HTML. + * + * @see README.org for markup details + * + * @internal + * @param String $text + * @return String HTML markup as a string + */ +function linkup_regexp($text) { + return preg_replace_callback("/(^|[^\w&\"\]])([@!\#\*:])([a-z0-9+-]+)(\b)/u", + "linkup_markup", $text); + +} + +/** + * linkup_skip_tags -- tags to skip wjen looking for markup + * + * @todo the whole range of tag that can contain A are 'flow elements' + * and 'phrasing elements' as defined at + * + * http://dev.w3.org/html5/markup/common-models.html + */ +function linkup_skip_tags() { + static $skip = array('a', + 'button', + 'canvas', + 'class', + 'code', + 'embed', + 'head', + 'iframe', + 'input', + 'link', + 'meta', + 'object', + 'param', + 'pre', + 'script', + 'style', + 'textarea', + ''); + + return $skip; +} + +/** + * Markup callback + * + * Generate HTML markup from linkup patterns, for a single matched + * pattern. It is used as a regular expression callback. + * + * It also takes care of permissions and entity validity, so that no + * link will be made to unauthorized or non-existing entities. + * + * @return String, the resulting markup + */ +function linkup_markup($matches) { + + $prefix = $matches[1]; + $marker = $matches[2]; + $subject = $matches[3]; + $text = "$marker$subject"; + + switch($marker) { + case "@": // user + if (preg_match("/^[a-z][\w\.-]+/i", $subject)) { + $entity = get_user_by_username($subject); + $text = linkup_markup_user($entity, $text); + // TODO trigger_plugin_hook('mention', 'user'); + } + break; + + case "!": // group + if (preg_match("/^[0-9]+$/", $subject)) { + // Get group by GUID + $entity = get_entity($subject); + // TODO if user can access group + } else if (preg_match("/^[a-z][\w+-]+$/i", $subject)) { + // Get group by alias + if (!elgg_is_active_plugin('group_alias')) { break; } + $entity = get_group_from_group_alias($subject); + } + $text = linkup_markup_group($entity, $text); + break; + + case "#": // hashtag or task + if (preg_match("/^[0-9]+$/", $subject) && elgg_is_active_plugin('tasks')) { + // Get task by GUID + $entity = get_entity($subject); + if (elgg_instanceof($entity, 'object', 'task') || + elgg_instanceof($entity, 'object', 'tasklist') || + elgg_instanceof($entity, 'object', 'tasklist_top')) { + // Linkup task + $text = linkup_markup_task($entity, $text); + break; + } + } + // Linkup hashtag + $text = linkup_link($text, "hashtag", "/tag/$subject"); + break; + + case "*": // entity + // Check that the subject is a GUID and current user can access + // the corresponding entity + if (!preg_match("/^[0-9]+$/", $subject)) { break; } + $entity = get_entity($subject); + if (elgg_instanceof($entity, 'user')) { + $text = linkup_markup_user($entity); + } + else if (elgg_instanceof($entity, 'group')) { + $text = linkup_markup_group($entity); + } + else if (elgg_instanceof($entity, 'object', 'task') || + elgg_instanceof($entity, 'object', 'tasklist') || + elgg_instanceof($entity, 'object', 'tasklist_top')) { + $text = linkup_markup_task($entity, $text); + } + else if (elgg_instanceof($entity, 'object')) { + // get subtype, check permissions, linkup + if (!elgg_trigger_plugin_hook('linkup', "object:{$entity->getSubtype()}", array('entity' => $entity))) { + // Default object view + $text = linkup_markup_object($entity); + } + } + break; + } + + return "$prefix$text"; +} + + +// TODO Move the following to a library + +/** + * Generic linkup markup + * + */ +function linkup_link($anchor, $css, $url, $title = "") { + + $vars = array('class' => "linkup $css", 'href' => $url, 'text' => $anchor); + if (!empty($title)) { + $vars['title'] = $title; + } + + return elgg_view('output/url', $vars); + +} + +/** + * Markup for a group + */ +function linkup_markup_group($entity, $default = "") { + + if (elgg_instanceof($entity, 'group')) { + if (elgg_is_active_plugin('group_alias')) { + $anchor = "!{$entity->alias}"; + } else { + $anchor = "!{$entity->username}"; + } + $css = "group"; + $url = $entity->getURL(); + + return linkup_link($anchor, $css, $url, elgg_echo('group') . ": {$entity->name}"); + } + return $default; +} + +/** + * Markup for a generic object + */ +function linkup_markup_object($entity, $default = "") { + + if (elgg_instanceof($entity, 'object') && $entity->isEnabled()) { + + $subtype = $entity->getSubtype(); + if (empty($subtype)) { + $subtype = 'default'; + } + + $anchor = "{$entity->name}"; + $css = elgg_get_friendly_title("object-{$subtype}"); + $url = $entity->getURL(); + + return linkup_link($anchor, $css, $url, elgg_echo("linkup:object:$subtype", array($entity->guid))); + } + + return $default; +} + +/** + * Markup for a task + */ +function linkup_markup_task($entity, $default = "") { + + if (!elgg_instanceof($entity, 'object')) { + return $default; + } + + $subtypes = array('task', 'tasklist', 'tasklist_top'); + $subtype = $entity->getSubtype(); + + if (!in_array($subtype, $subtypes)) { + return $default; + } + + $anchor = "#$entity->guid"; + $css = "$subtype"; + if ('task' == $subtype) { + $css.= " task-status-{$entity->status}"; + } + $url = $entity->getURL(); + $title = elgg_echo('task') . " $entity->title"; + + return linkup_link($anchor, $css, $url, $title); + +} + +/** + * Markup for a user + */ +function linkup_markup_user($entity, $default = "") { + + if (elgg_instanceof($entity, 'user') && !$entity->isBanned()) { + + $anchor = "@{$entity->username}"; + $css = "user"; + $url = $entity->getURL(); + + return linkup_link($anchor, $css, $url, $entity->name); + } + + return $default; +} + |