10 files changed, 481 insertions, 0 deletions

diff --git a/mod/likes/actions/likes/add.php b/mod/likes/actions/likes/add.php
new file mode 100644
index 000000000..a6a8d6c45
--- /dev/null
+++ b/mod/likes/actions/likes/add.php
@@ -0,0 +1,50 @@
+<?php
+/**
+ * Elgg add like action
+ *
+ */
+
+$entity_guid = (int) get_input('guid');
+
+//check to see if the user has already liked the item
+if (elgg_annotation_exists($entity_guid, 'likes')) {
+	system_message(elgg_echo("likes:alreadyliked"));
+	forward(REFERER);
+}
+// Let's see if we can get an entity with the specified GUID
+$entity = get_entity($entity_guid);
+if (!$entity) {
+	register_error(elgg_echo("likes:notfound"));
+	forward(REFERER);
+}
+
+// limit likes through a plugin hook (to prevent liking your own content for example)
+if (!$entity->canAnnotate(0, 'likes')) {
+	// plugins should register the error message to explain why liking isn't allowed
+	forward(REFERER);
+}
+
+$user = elgg_get_logged_in_user_entity();
+$annotation = create_annotation($entity->guid,
+								'likes',
+								"likes",
+								"",
+								$user->guid,
+								$entity->access_id);
+
+// tell user annotation didn't work if that is the case
+if (!$annotation) {
+	register_error(elgg_echo("likes:failure"));
+	forward(REFERER);
+}
+
+// notify if poster wasn't owner
+if ($entity->owner_guid != $user->guid) {
+
+	likes_notify_user($entity->getOwnerEntity(), $user, $entity);
+}
+
+system_message(elgg_echo("likes:likes"));
+
+// Forward back to the page where the user 'liked' the object
+forward(REFERER);
diff --git a/mod/likes/actions/likes/delete.php b/mod/likes/actions/likes/delete.php
new file mode 100644
index 000000000..322d512e8
--- /dev/null
+++ b/mod/likes/actions/likes/delete.php
@@ -0,0 +1,31 @@
+<?php
+/**
+ * Elgg delete like action
+ *
+ */
+
+// Support deleting by id in case we're deleting another user's likes
+$id = (int) get_input('id');
+
+$like = NULL;
+if ($id) {
+	$like = elgg_get_annotation_from_id($id);
+}
+
+if (!$like) {
+	$likes = elgg_get_annotations(array(
+		'guid' => (int) get_input('guid'),
+		'annotation_owner_guid' => elgg_get_logged_in_user_guid(),
+		'annotation_name' => 'likes',
+	));
+	$like = $likes[0];
+}
+
+if ($like && $like->canEdit()) {
+	$like->delete();
+	system_message(elgg_echo("likes:deleted"));
+	forward(REFERER);
+}
+
+register_error(elgg_echo("likes:notdeleted"));
+forward(REFERER);
diff --git a/mod/likes/languages/en.php b/mod/likes/languages/en.php
new file mode 100644
index 000000000..bdbd2a963
--- /dev/null
+++ b/mod/likes/languages/en.php
@@ -0,0 +1,45 @@
+<?php
+/**
+ * Likes English language file
+ */
+
+$english = array(
+	'likes:this' => 'liked this',
+	'likes:deleted' => 'Your like has been removed',
+	'likes:see' => 'See who liked this',
+	'likes:remove' => 'Unlike this',
+	'likes:notdeleted' => 'There was a problem removing your like',
+	'likes:likes' => 'You now like this item',
+	'likes:failure' => 'There was a problem liking this item',
+	'likes:alreadyliked' => 'You have already liked this item',
+	'likes:notfound' => 'The item you are trying to like cannot be found',
+	'likes:likethis' => 'Like this',
+	'likes:userlikedthis' => '%s like',
+	'likes:userslikedthis' => '%s likes',
+	'likes:river:annotate' => 'likes',
+	'likes:delete:confirm' => 'Are you sure you want to delete this like?',
+
+	'river:likes' => 'likes %s %s',
+
+	// notifications. yikes.
+	'likes:notifications:subject' => '%s likes your post "%s"',
+	'likes:notifications:body' =>
+'Hi %1$s,
+
+%2$s likes your post "%3$s" on %4$s
+
+See your original post here:
+
+%5$s
+
+or view %2$s\'s profile here:
+
+%6$s
+
+Thanks,
+%4$s
+',
+	
+);
+
+add_translation('en', $english);
diff --git a/mod/likes/manifest.xml b/mod/likes/manifest.xml
new file mode 100644
index 000000000..62835fcf5
--- /dev/null
+++ b/mod/likes/manifest.xml
@@ -0,0 +1,17 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<plugin_manifest xmlns="http://www.elgg.org/plugin_manifest/1.8">
+	<name>Likes</name>
+	<author>Core developers</author>
+	<version>1.8</version>
+	<category>bundled</category>
+	<category>social</category>
+	<description>Enables users to like content on the site.</description>
+	<website>http://www.elgg.org/</website>
+	<copyright>See COPYRIGHT.txt</copyright>
+	<license>GNU General Public License version 2</license>
+	<requires>
+		<type>elgg_release</type>
+		<version>1.8</version>
+	</requires>
+	<activate_on_install>true</activate_on_install>
+</plugin_manifest>
diff --git a/mod/likes/start.php b/mod/likes/start.php
new file mode 100644
index 000000000..0f8e12159
--- /dev/null
+++ b/mod/likes/start.php
@@ -0,0 +1,171 @@
+<?php
+/**
+ * Likes plugin
+ *
+ */
+
+elgg_register_event_handler('init', 'system', 'likes_init');
+
+function likes_init() {
+
+	elgg_extend_view('css/elgg', 'likes/css');
+	elgg_extend_view('js/elgg', 'likes/js');
+
+	// registered with priority < 500 so other plugins can remove likes
+	elgg_register_plugin_hook_handler('register', 'menu:river', 'likes_river_menu_setup', 400);
+	elgg_register_plugin_hook_handler('register', 'menu:entity', 'likes_entity_menu_setup', 400);
+
+	$actions_base = elgg_get_plugins_path() . 'likes/actions/likes';
+	elgg_register_action('likes/add', "$actions_base/add.php");
+	elgg_register_action('likes/delete', "$actions_base/delete.php");
+}
+
+/**
+ * Add likes to entity menu at end of the menu
+ */
+function likes_entity_menu_setup($hook, $type, $return, $params) {
+	if (elgg_in_context('widgets')) {
+		return $return;
+	}
+
+	$entity = $params['entity'];
+
+	// likes button
+	$options = array(
+		'name' => 'likes',
+		'text' => elgg_view('likes/button', array('entity' => $entity)),
+		'href' => false,
+		'priority' => 1000,
+	);
+	$return[] = ElggMenuItem::factory($options);
+
+	// likes count
+	$count = elgg_view('likes/count', array('entity' => $entity));
+	if ($count) {
+		$options = array(
+			'name' => 'likes_count',
+			'text' => $count,
+			'href' => false,
+			'priority' => 1001,
+		);
+		$return[] = ElggMenuItem::factory($options);
+	}
+
+	return $return;
+}
+
+/**
+ * Add a like button to river actions
+ */
+function likes_river_menu_setup($hook, $type, $return, $params) {
+	if (elgg_is_logged_in()) {
+		$item = $params['item'];
+
+		// only like group creation #3958
+		if ($item->type == "group" && $item->view != "river/group/create") {
+			return $return;
+		}
+
+		// don't like users #4116
+		if ($item->type == "user") {
+			return $return;
+		}
+		
+		$object = $item->getObjectEntity();
+		if (!elgg_in_context('widgets') && $item->annotation_id == 0) {
+			if ($object->canAnnotate(0, 'likes')) {
+				// like button
+				$options = array(
+					'name' => 'likes',
+					'href' => false,
+					'text' => elgg_view('likes/button', array('entity' => $object)),
+					'is_action' => true,
+					'priority' => 100,
+				);
+				$return[] = ElggMenuItem::factory($options);
+
+				// likes count
+				$count = elgg_view('likes/count', array('entity' => $object));
+				if ($count) {
+					$options = array(
+						'name' => 'likes_count',
+						'text' => $count,
+						'href' => false,
+						'priority' => 101,
+					);
+					$return[] = ElggMenuItem::factory($options);
+				}
+			}
+		}
+	}
+
+	return $return;
+}
+
+/**
+ * Count how many people have liked an entity.
+ *
+ * @param  ElggEntity $entity
+ *
+ * @return int Number of likes
+ */
+function likes_count($entity) {
+	$type = $entity->getType();
+	$params = array('entity' => $entity);
+	$number = elgg_trigger_plugin_hook('likes:count', $type, $params, false);
+
+	if ($number) {
+		return $number;
+	} else {
+		return $entity->countAnnotations('likes');
+	}
+}
+
+/**
+ * Notify $user that $liker liked his $entity.
+ *
+ * @param type $user
+ * @param type $liker
+ * @param type $entity 
+ */
+function likes_notify_user(ElggUser $user, ElggUser $liker, ElggEntity $entity) {
+	
+	if (!$user instanceof ElggUser) {
+		return false;
+	}
+	
+	if (!$liker instanceof ElggUser) {
+		return false;
+	}
+	
+	if (!$entity instanceof ElggEntity) {
+		return false;
+	}
+	
+	$title_str = $entity->title;
+	if (!$title_str) {
+		$title_str = elgg_get_excerpt($entity->description);
+	}
+
+	$site = get_config('site');
+
+	$subject = elgg_echo('likes:notifications:subject', array(
+					$liker->name,
+					$title_str
+				));
+
+	$body = elgg_echo('likes:notifications:body', array(
+					$user->name,
+					$liker->name,
+					$title_str,
+					$site->name,
+					$entity->getURL(),
+					$liker->getURL()
+				));
+
+	notify_user($user->guid,
+				$liker->guid,
+				$subject,
+				$body
+			);
+}
\ No newline at end of file
diff --git a/mod/likes/views/default/annotation/likes.php b/mod/likes/views/default/annotation/likes.php
new file mode 100644
index 000000000..2b5acc520
--- /dev/null
+++ b/mod/likes/views/default/annotation/likes.php
@@ -0,0 +1,49 @@
+<?php
+/**
+ * Elgg show the users who liked the object
+ *
+ * @uses $vars['annotation']
+ */
+
+if (!isset($vars['annotation'])) {
+	return true;
+}
+
+$like = $vars['annotation'];
+
+$user = $like->getOwnerEntity();
+if (!$user) {
+	return true;
+}
+
+$user_icon = elgg_view_entity_icon($user, 'tiny');
+$user_link = elgg_view('output/url', array(
+	'href' => $user->getURL(),
+	'text' => $user->name,
+	'is_trusted' => true,
+));
+
+$likes_string = elgg_echo('likes:this');
+
+$friendlytime = elgg_view_friendly_time($like->time_created);
+
+if ($like->canEdit()) {
+	$delete_button = elgg_view("output/confirmlink",array(
+    	'href' => "action/likes/delete?id={$like->id}",
+    	'text' => "<span class=\"elgg-icon elgg-icon-delete float-alt\"></span>",
+    	'confirm' => elgg_echo('likes:delete:confirm'),
+    	'encode_text' => false,
+    ));
+}
+
+$body = <<<HTML
+<p class="mbn">
+	$delete_button
+	$user_link $likes_string
+	<span class="elgg-subtext">
+		$friendlytime
+	</span>
+</p>
+HTML;
+
+echo elgg_view_image_block($user_icon, $body);
diff --git a/mod/likes/views/default/likes/button.php b/mod/likes/views/default/likes/button.php
new file mode 100644
index 000000000..bc7c8fd8a
--- /dev/null
+++ b/mod/likes/views/default/likes/button.php
@@ -0,0 +1,39 @@
+<?php
+/**
+ * Elgg likes button
+ *
+ * @uses $vars['entity']
+ */
+
+if (!isset($vars['entity'])) {
+	return true;
+}
+
+$guid = $vars['entity']->getGUID();
+
+// check to see if the user has already liked this
+if (elgg_is_logged_in() && $vars['entity']->canAnnotate(0, 'likes')) {
+	if (!elgg_annotation_exists($guid, 'likes')) {
+		$url = elgg_get_site_url() . "action/likes/add?guid={$guid}";
+		$params = array(
+			'href' => $url,
+			'text' => elgg_view_icon('thumbs-up'),
+			'title' => elgg_echo('likes:likethis'),
+			'is_action' => true,
+			'is_trusted' => true,
+		);
+		$likes_button = elgg_view('output/url', $params);
+	} else {
+		$url = elgg_get_site_url() . "action/likes/delete?guid={$guid}";
+		$params = array(
+			'href' => $url,
+			'text' => elgg_view_icon('thumbs-up-alt'),
+			'title' => elgg_echo('likes:remove'),
+			'is_action' => true,
+			'is_trusted' => true,
+		);
+		$likes_button = elgg_view('output/url', $params);
+	}
+}
+
+echo $likes_button;
diff --git a/mod/likes/views/default/likes/count.php b/mod/likes/views/default/likes/count.php
new file mode 100644
index 000000000..071a069bd
--- /dev/null
+++ b/mod/likes/views/default/likes/count.php
@@ -0,0 +1,36 @@
+<?php
+/**
+ * Count of who has liked something
+ *
+ *  @uses $vars['entity']
+ */
+
+
+$list = '';
+$num_of_likes = likes_count($vars['entity']);
+$guid = $vars['entity']->getGUID();
+
+if ($num_of_likes) {
+	// display the number of likes
+	if ($num_of_likes == 1) {
+		$likes_string = elgg_echo('likes:userlikedthis', array($num_of_likes));
+	} else {
+		$likes_string = elgg_echo('likes:userslikedthis', array($num_of_likes));
+	}
+	$params = array(
+		'text' => $likes_string,
+		'title' => elgg_echo('likes:see'),
+		'rel' => 'popup',
+		'href' => "#likes-$guid"
+	);
+	$list = elgg_view('output/url', $params);
+	$list .= "<div class='elgg-module elgg-module-popup elgg-likes hidden clearfix' id='likes-$guid'>";
+	$list .= elgg_list_annotations(array(
+		'guid' => $guid,
+		'annotation_name' => 'likes',
+		'limit' => 99,
+		'list_class' => 'elgg-list-likes'
+	));
+	$list .= "</div>";
+	echo $list;
+}
diff --git a/mod/likes/views/default/likes/css.php b/mod/likes/views/default/likes/css.php
new file mode 100644
index 000000000..1ec07b366
--- /dev/null
+++ b/mod/likes/views/default/likes/css.php
@@ -0,0 +1,17 @@
+<?php
+/**
+ * Likes CSS
+ */
+?>
+
+/* ***************************************
+	Likes
+*************************************** */
+.elgg-likes {
+	width: 345px;
+	position: absolute;
+}
+
+.elgg-menu .elgg-menu-item-likes-count {
+	margin-left: 3px;
+}
diff --git a/mod/likes/views/default/likes/js.php b/mod/likes/views/default/likes/js.php
new file mode 100644
index 000000000..f701ebedf
--- /dev/null
+++ b/mod/likes/views/default/likes/js.php
@@ -0,0 +1,26 @@
+<?php
+/**
+ * Likes JavaScript extension for elgg.js
+ */
+?>
+
+/**
+ * Repositions the likes popup
+ *
+ * @param {String} hook    'getOptions'
+ * @param {String} type    'ui.popup'
+ * @param {Object} params  An array of info about the target and source.
+ * @param {Object} options Options to pass to
+ *
+ * @return {Object}
+ */
+elgg.ui.likesPopupHandler = function(hook, type, params, options) {
+	if (params.target.hasClass('elgg-likes')) {
+		options.my = 'right bottom';
+		options.at = 'left top';
+		return options;
+	}
+	return null;
+};
+
+elgg.register_hook_handler('getOptions', 'ui.popup', elgg.ui.likesPopupHandler);
\ No newline at end of file