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+                    GNU AFFERO GENERAL PUBLIC LICENSE
+                       Version 3, 19 November 2007
+
+ Copyright (C) 2007 Free Software Foundation, Inc. <http://fsf.org/>
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+                            Preamble
+
+  The GNU Affero General Public License is a free, copyleft license for
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+  16. Limitation of Liability.
+
+  IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
+WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS
+THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY
+GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE
+USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF
+DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD
+PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS),
+EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
+SUCH DAMAGES.
+
+  17. Interpretation of Sections 15 and 16.
+
+  If the disclaimer of warranty and limitation of liability provided
+above cannot be given local legal effect according to their terms,
+reviewing courts shall apply local law that most closely approximates
+an absolute waiver of all civil liability in connection with the
+Program, unless a warranty or assumption of liability accompanies a
+copy of the Program in return for a fee.
+
+                     END OF TERMS AND CONDITIONS
+
+            How to Apply These Terms to Your New Programs
+
+  If you develop a new program, and you want it to be of the greatest
+possible use to the public, the best way to achieve this is to make it
+free software which everyone can redistribute and change under these terms.
+
+  To do so, attach the following notices to the program.  It is safest
+to attach them to the start of each source file to most effectively
+state the exclusion of warranty; and each file should have at least
+the "copyright" line and a pointer to where the full notice is found.
+
+    <one line to give the program's name and a brief idea of what it does.>
+    Copyright (C) <year>  <name of author>
+
+    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/>.
+
+Also add information on how to contact you by electronic and paper mail.
+
+  If your software can interact with users remotely through a computer
+network, you should also make sure that it provides a way for users to
+get its source.  For example, if your program is a web application, its
+interface could display a "Source" link that leads users to an archive
+of the code.  There are many ways you could offer source, and different
+solutions will be better for different programs; see section 13 for the
+specific requirements.
+
+  You should also get your employer (if you work as a programmer) or school,
+if any, to sign a "copyright disclaimer" for the program, if necessary.
+For more information on this, and how to apply and follow the GNU AGPL, see
+<http://www.gnu.org/licenses/>.
diff --git a/mod/linkup/README.txt b/mod/linkup/README.txt
new file mode 100644
index 000000000..7c72a87f2
--- /dev/null
+++ b/mod/linkup/README.txt
@@ -0,0 +1,90 @@
+# Lorea Linkup plugin for Elgg 1.8
+
+Linkup provides a simple markup to turn references to known entities
+into clickable links.
+
+It recognizes:
+
+  - @username and links to the user profile
+  - #1234 and links to the related task entity, otherwise,
+  - #hashtag and links to the tag's page (can be #12 if it's not a task)
+  - !1234 and links to the group's page whose GUID is "1234"
+  - !group and links to the group's page whose group_alias is "group"
+     (requires the (https://gitorious.org/lorea/group_alias)[group_alias] plugin)
+  - *1234 and links to the corresponding ElggEntity page for that GUID
+
+It works by scraping the resulting view and changing the markup
+on-the-fly for the current user: if they do not have access to the
+target entity, the link won't be made. Therefore, the plugin can be
+activated and deactivated without changing anything from the original
+contents. It also create links to entities once they're created.
+
+It depends on libxml being installed and available. Linkup uses
+[DOMDocument](http://php.net/dom) to parse the tags and extract the
+parts to be checked for markup. It works independently from any
+plugins.
+
+There is a plugin hook 'linkup','object:$subtype' for plugin authors
+to add their own entity-specific markup functions. See how the tasks
+are handled to get started.
+
+This plugin is brought to you by Lorea Faeries, and available under
+the GNU Affero General Public License version 3, or later (see
+LICENSE.txt.)
+
+
+## Releases
+
+Current release is **v0.2.4**.
+
+Releases follow the [Semantic Versioning](http://semver.org/) rules.
+
+
+## Roadmap / Changes
+
+### Version 0.1.0, 2012-08-12 [deprecated]
+
+This is a rewrite from a couple of weeks ago before the CPU fan lost power, 
+and I couldn't transmit the code before I left Europe. It recognizes basic 
+cases for users and groups. Generic entities are still to be supported.
+
+### Version 0.2.0, 2012-10-12 [deprecated]
+
+- Add support for generic entities and proper permissions check. 
+- Now uses DOMDocument to restrict usage of the regular expression to safer 
+  zones.
+- Add a plugin hook 'linkup','object:$subtype' for plugins to provide a 
+  specific markup for their entities.
+- Add support for tasks as an example extension.
+
+### Version 0.2.1, 2012-11-01 [deprecated]
+
+- Fix erroneous function call
+- Update README
+- Update copyright information for AGPLv3+
+- Ready for #Foxglove!
+
+### Version 0.2.2, 2012-11-04 [deprecated]
+
+- Do not try to markup empty nodes (fixes #1502591)
+- Add support for subgroup aliases (e.g. lorea+code)
+- Updated version for #Foxglove
+
+### Version 0.2.3, ? [deprecated]
+
+Missed?
+
+### Version 0.2.4, 2013-01-18 *foxglove*
+
+- Fix bug introduced in acf1af78 that prevented the markup from being applied.
+
+### Version 0.3.0
+
+- Add support for CSS icons for generated links.
+- Add descriptive titles from entity context.
+
+### Version 0.4.0
+
+- Add support for autocompletion preview (to make it easier to
+  type shortcuts.)
+
diff --git a/mod/linkup/languages/en.php b/mod/linkup/languages/en.php
new file mode 100644
index 000000000..3d08435e2
--- /dev/null
+++ b/mod/linkup/languages/en.php
@@ -0,0 +1,39 @@
+<?php
+/**
+ * Linkup -- Translation strings for English
+ *
+ * @package        Lorea
+ * @subpackage     Linkup
+ *
+ * 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/>.
+ */
+$English = array(
+	'linkup:object:default'			=> 'object',
+
+	'linkup:object:blog'			=> 'blog article',
+	'linkup:object:bookmark'		=> 'bookmark',
+	'linkup:object:groupforumtopic'		=> 'discussion topic',
+	'linkup:object:message'			=> 'message',
+	'linkup:object:reported_content'	=> 'reported content',
+	'linkup:object:task'			=> 'task',
+	'linkup:object:tasklist'		=> 'task list',
+	'linkup:object:thewire'			=> 'wire update',
+	'linkup:object:topicreply'		=> 'discussion response',
+);
+
+add_translation('en', $English);
+unset($English);
diff --git a/mod/linkup/manifest.xml b/mod/linkup/manifest.xml
new file mode 100644
index 000000000..619d0ea4f
--- /dev/null
+++ b/mod/linkup/manifest.xml
@@ -0,0 +1,36 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<plugin_manifest xmlns="http://www.elgg.org/plugin_manifest/1.8">
+	<name>Linkup</name>
+	<author>Lorea Developers</author>
+	<version>0.2.4</version>
+	<copyright>Lorea Faeries &lt;federation@lorea.org&gt;</copyright>
+	<category>lorea</category>
+	<category>usability</category>
+	<category>markup</category>
+	<blurb>Provide simple markup to interconnect arbitrary entities across the Elgg site.</blurb>
+	<description>
+    	Allow simple markup to link arbitrary entities across Elgg
+    	modules. See README.txt for details.
+	</description>
+	<website>https://lorea.org/plugin/linkup</website>
+	<bugtracker>https://n-1.cc/tasks/view/1566412/linkup</bugtracker>
+	<repository>https://gitorious.org/lorea/linkup</repository>
+	<donations>https://lorea.org/support</donations>
+	<license>GNU Affero General Public License version 3, or later</license>
+	<requires>
+		<type>elgg_release</type>
+		<version>1.8</version>
+	</requires>
+	<requires>
+		<type>php_extension</type>
+		<name>libxml</name>
+	</requires>
+	<suggests>
+		<type>plugin</type>
+		<name>group_alias</name>
+	</suggests>
+	<suggests>
+		<type>plugin</type>
+		<name>tasks</name>
+	</suggests>
+</plugin_manifest>
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;
+}
+
diff --git a/mod/linkup/views/default/linkup/css.php b/mod/linkup/views/default/linkup/css.php
new file mode 100644
index 000000000..3746e262b
--- /dev/null
+++ b/mod/linkup/views/default/linkup/css.php
@@ -0,0 +1,31 @@
+<?php
+/**
+ * Linkup -- Stylesheet
+ *
+ * It recognizes: @username, !group-alias, !group-guid, #task-guid, #hashtag,
+ * and *entity-guid.
+ *
+ * @package        Lorea
+ * @subpackage     Linkup
+ *
+ * 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/>.
+ */
+?>
+.linkup.task-status-closed,
+.linkup.task-status-done {
+	text-decoration: line-through;
+}