WordPress/wp-admin/includes/plugin-install.php

<?php
/**
 * WordPress Plugin Install Administration API
 *
 * @package WordPress
 * @subpackage Administration
 */

/**
 * Retrieve plugin installer pages from WordPress Plugins API.
 *
 * It is possible for a plugin to override the Plugin API result with three
 * filters. Assume this is for plugins, which can extend on the Plugin Info to
 * offer more choices. This is very powerful and must be used with care, when
 * overridding the filters.
 *
 * The first filter, 'plugins_api_args', is for the args and gives the action as
 * the second parameter. The hook for 'plugins_api_args' must ensure that an
 * object is returned.
 *
 * The second filter, 'plugins_api', is the result that would be returned.
 *
 * @since 2.7.0
 *
 * @param string $action
 * @param array|object $args Optional. Arguments to serialize for the Plugin Info API.
 * @return mixed
 */
function plugins_api($action, $args = null) {

	if( is_array($args) )
		$args = (object)$args;

	if ( !isset($args->per_page) )
		$args->per_page = 24;

	$args = apply_filters('plugins_api_args', $args, $action); //NOTE: Ensure that an object is returned via this filter.
	$res = apply_filters('plugins_api', false, $action, $args); //NOTE: Allows a plugin to completely override the builtin WordPress.org API.

	if ( ! $res ) {
		$request = wp_remote_post('http://api.wordpress.org/plugins/info/1.0/', array( 'body' => array('action' => $action, 'request' => serialize($args))) );
		if ( is_wp_error($request) ) {
			$res = new WP_Error('plugins_api_failed', __('An Unexpected HTTP Error occurred during the API request.</p> <p><a href="?" onclick="document.location.reload(); return false;">Try again</a>'), $request->get_error_message() );
		} else {
			$res = unserialize($request['body']);
			if ( ! $res )
				$res = new WP_Error('plugins_api_failed', __('An unknown error occurred'), $request['body']);
		}
	}

	return apply_filters('plugins_api_result', $res, $action, $args);
}

/**
 * Retrieve popular WordPress plugin tags.
 *
 * @since 2.7.0
 *
 * @param array $args
 * @return array
 */
function install_popular_tags( $args = array() ) {
	if ( ! ($cache = wp_cache_get('popular_tags', 'api')) && ! ($cache = get_option('wporg_popular_tags')) )
		add_option('wporg_popular_tags', array(), '', 'no'); ///No autoload.

	if ( $cache && $cache->timeout + 3 * 60 * 60 > time() )
		return $cache->cached;

	$tags = plugins_api('hot_tags', $args);

	if ( is_wp_error($tags) )
		return $tags;

	$cache = (object) array('timeout' => time(), 'cached' => $tags);

	update_option('wporg_popular_tags', $cache);
	wp_cache_set('popular_tags', $cache, 'api');

	return $tags;
}
add_action('install_plugins_search', 'install_search', 10, 1);

/**
 * Display search results and display as tag cloud.
 *
 * @since 2.7.0
 *
 * @param string $page
 */
function install_search($page) {
	$type = isset($_REQUEST['type']) ? stripslashes( $_REQUEST['type'] ) : '';
	$term = isset($_REQUEST['s']) ? stripslashes( $_REQUEST['s'] ) : '';

	$args = array();

	switch( $type ){
		case 'tag':
			$args['tag'] = sanitize_title_with_dashes($term);
			break;
		case 'term':
			$args['search'] = $term;
			break;
		case 'author':
			$args['author'] = $term;
			break;
	}

	$args['page'] = $page;

	$api = plugins_api('query_plugins', $args);

	if ( is_wp_error($api) )
		wp_die($api);

	add_action('install_plugins_table_header', 'install_search_form');

	display_plugins_table($api->plugins, $api->info['page'], $api->info['pages']);

	return;
}

add_action('install_plugins_dashboard', 'install_dashboard');
function install_dashboard() {
	?>
	<p><?php _e('Plugins extend and expand the functionality of WordPress. You may automatically install plugins from the <a href="http://wordpress.org/extend/plugins/">WordPress Plugin Directory</a> or upload a plugin in .zip format via this page.') ?></p>

	<h4><?php _e('Search') ?></h4>
	<p class="install-help"><?php _e('Search for plugins by keyword, author, or tag.') ?></p>
	<?php install_search_form(); ?>

	<h4><?php _e('Popular tags') ?></h4>
	<p class="install-help"><?php _e('You may also browse based on the most popular tags in the Plugin Directory:') ?></p>
	<?php

	$api_tags = install_popular_tags();

	//Set up the tags in a way which can be interprated by wp_generate_tag_cloud()
	$tags = array();
	foreach ( (array)$api_tags as $tag )
		$tags[ $tag['name'] ] = (object) array(
								'link' => clean_url( admin_url('plugin-install.php?tab=search&type=tag&s=' . urlencode($tag['name'])) ),
								'name' => $tag['name'],
								'id' => sanitize_title_with_dashes($tag['name']),
								'count' => $tag['count'] );
	echo '<p class="popular-tags">';
	echo wp_generate_tag_cloud($tags, array( 'single_text' => __('%d plugin'), 'multiple_text' => __('%d plugins') ) );
	echo '</p><br class="clear" />';
}

/**
 * Display search form for searching plugins.
 *
 * @since 2.7.0
 */
function install_search_form(){
	$type = isset($_REQUEST['type']) ? stripslashes( $_REQUEST['type'] ) : '';
	$term = isset($_REQUEST['s']) ? stripslashes( $_REQUEST['s'] ) : '';

	?><form id="search-plugins" method="post" action="<?php echo admin_url('plugin-install.php?tab=search') ?>">
		<select name="type" id="typeselector">
			<option value="term"<?php selected('term', $type) ?>><?php _e('Term') ?></option>
			<option value="author"<?php selected('author', $type) ?>><?php _e('Author') ?></option>
			<option value="tag"<?php selected('tag', $type) ?>><?php _e('Tag') ?></option>
		</select>
		<input type="text" name="s" class="search-input" value="<?php echo attribute_escape($term) ?>" />
		<input type="submit" name="search" value="<?php echo attribute_escape(__('Search')) ?>" class="button" />
	</form><?php
}

add_action('install_plugins_featured', 'install_featured', 10, 1);
/**
 * Display featured plugins.
 *
 * @since 2.7.0
 *
 * @param string $page
 */
function install_featured($page = 1) {
	$args = array('browse' => 'featured', 'page' => $page);
	$api = plugins_api('query_plugins', $args);
	if ( is_wp_error($api) )
		wp_die($api);
	display_plugins_table($api->plugins, $api->info['page'], $api->info['pages']);
}

add_action('install_plugins_popular', 'install_popular', 10, 1);
/**
 * Display popular plugins.
 *
 * @since 2.7.0
 *
 * @param string $page
 */
function install_popular($page = 1) {
	$args = array('browse' => 'popular', 'page' => $page);
	$api = plugins_api('query_plugins', $args);
	display_plugins_table($api->plugins, $api->info['page'], $api->info['pages']);
}

add_action('install_plugins_upload', 'install_plugins_upload', 10, 1);
/**
 * Upload from zip
 * @since 2.8.0
 * 
 * @param string $page
 */
function install_plugins_upload( $page = 1 ) {
?>
	<h4><?php _e('Install a plugin in .zip format') ?></h4>
	<p class="install-help"><?php _e('If you have a plugin in a .zip format, You may install it by uploading it here.') ?></p>
	<form method="post" enctype="multipart/form-data" action="<?php echo admin_url('plugin-install.php?tab=do_upload') ?>">
		<?php wp_nonce_field( 'plugin-upload') ?>
		<input type="file" name="pluginzip" />
		<input type="submit" class="button" value="<?php _e('Install Now') ?>" />
	</form>
<?php
}

add_action('install_plugins_new', 'install_new', 10, 1);
/**
 * Display new plugins.
 *
 * @since 2.7.0
 *
 * @param string $page
 */
function install_new($page = 1) {
	$args = array('browse' => 'new', 'page' => $page);
	$api = plugins_api('query_plugins', $args);
	if ( is_wp_error($api) )
		wp_die($api);
	display_plugins_table($api->plugins, $api->info['page'], $api->info['pages']);
}
add_action('install_plugins_updated', 'install_updated', 10, 1);


/**
 * Display recently updated plugins.
 *
 * @since 2.7.0
 *
 * @param string $page
 */
function install_updated($page = 1) {
	$args = array('browse' => 'updated', 'page' => $page);
	$api = plugins_api('query_plugins', $args);
	display_plugins_table($api->plugins, $api->info['page'], $api->info['pages']);
}

/**
 * Display plugin content based on plugin list.
 *
 * @since 2.7.0
 *
 * @param array $plugins List of plugins.
 * @param string $page
 * @param int $totalpages Number of pages.
 */
function display_plugins_table($plugins, $page = 1, $totalpages = 1){
	$type = isset($_REQUEST['type']) ? stripslashes( $_REQUEST['type'] ) : '';
	$term = isset($_REQUEST['s']) ? stripslashes( $_REQUEST['s'] ) : '';

	$plugins_allowedtags = array('a' => array('href' => array(),'title' => array(), 'target' => array()),
								'abbr' => array('title' => array()),'acronym' => array('title' => array()),
								'code' => array(), 'pre' => array(), 'em' => array(),'strong' => array(),
								'ul' => array(), 'ol' => array(), 'li' => array(), 'p' => array(), 'br' => array());

?>
	<div class="tablenav">
		<div class="alignleft actions">
		<?php do_action('install_plugins_table_header'); ?>
		</div>
		<?php
			$url = clean_url($_SERVER['REQUEST_URI']);
			if ( ! empty($term) )
				$url = add_query_arg('s', $term, $url);
			if ( ! empty($type) )
				$url = add_query_arg('type', $type, $url);

			$page_links = paginate_links( array(
				'base' => add_query_arg('paged', '%#%', $url),
				'format' => '',
				'prev_text' => __('&laquo;'),
				'next_text' => __('&raquo;'),
				'total' => $totalpages,
				'current' => $page
			));

			if ( $page_links )
				echo "\t\t<div class='tablenav-pages'>$page_links</div>";
?>
		<br class="clear" />
	</div>
	<table class="widefat" id="install-plugins" cellspacing="0">
		<thead>
			<tr>
				<th scope="col" class="name"><?php _e('Name'); ?></th>
				<th scope="col" class="num"><?php _e('Version'); ?></th>
				<th scope="col" class="num"><?php _e('Rating'); ?></th>
				<th scope="col" class="desc"><?php _e('Description'); ?></th>
				<th scope="col" class="action-links"><?php _e('Actions'); ?></th>
			</tr>
		</thead>

		<tfoot>
			<tr>
				<th scope="col" class="name"><?php _e('Name'); ?></th>
				<th scope="col" class="num"><?php _e('Version'); ?></th>
				<th scope="col" class="num"><?php _e('Rating'); ?></th>
				<th scope="col" class="desc"><?php _e('Description'); ?></th>
				<th scope="col" class="action-links"><?php _e('Actions'); ?></th>
			</tr>
		</tfoot>

		<tbody class="plugins">
		<?php
			if( empty($plugins) )
				echo '<tr><td colspan="5">', __('No plugins match your request.'), '</td></tr>';

			foreach( (array) $plugins as $plugin ){
				if ( is_object($plugin) )
					$plugin = (array) $plugin;

				$title = wp_kses($plugin['name'], $plugins_allowedtags);
				$description = wp_kses($plugin['description'], $plugins_allowedtags);
				$version = wp_kses($plugin['version'], $plugins_allowedtags);

				$name = strip_tags($title . ' ' . $version);

				$author = $plugin['author'];
				if( ! empty($plugin['author']) )
					$author = ' <cite>' . sprintf( __('By %s'), $author ) . '.</cite>';

				$author = wp_kses($author, $plugins_allowedtags);

				if( isset($plugin['homepage']) )
					$title = '<a target="_blank" href="' . attribute_escape($plugin['homepage']) . '">' . $title . '</a>';

				$action_links = array();
				$action_links[] = '<a href="' . admin_url('plugin-install.php?tab=plugin-information&amp;plugin=' . $plugin['slug'] .
									'&amp;TB_iframe=true&amp;width=600&amp;height=800') . '" class="thickbox onclick" title="' .
									attribute_escape($name) . '">' . __('Install') . '</a>';

				$action_links = apply_filters('plugin_install_action_links', $action_links, $plugin);
			?>
			<tr>
				<td class="name"><?php echo $title; ?></td>
				<td class="vers"><?php echo $version; ?></td>
				<td class="vers">
					<div class="star-holder" title="<?php printf(_n('(based on %s rating)', '(based on %s ratings)', $plugin['num_ratings']), number_format_i18n($plugin['num_ratings'])) ?>">
						<div class="star star-rating" style="width: <?php echo attribute_escape($plugin['rating']) ?>px"></div>
						<div class="star star5"><img src="<?php echo admin_url('images/star.gif'); ?>" alt="<?php _e('5 stars') ?>" /></div>
						<div class="star star4"><img src="<?php echo admin_url('images/star.gif'); ?>" alt="<?php _e('4 stars') ?>" /></div>
						<div class="star star3"><img src="<?php echo admin_url('images/star.gif'); ?>" alt="<?php _e('3 stars') ?>" /></div>
						<div class="star star2"><img src="<?php echo admin_url('images/star.gif'); ?>" alt="<?php _e('2 stars') ?>" /></div>
						<div class="star star1"><img src="<?php echo admin_url('images/star.gif'); ?>" alt="<?php _e('1 star') ?>" /></div>
					</div>
				</td>
				<td class="desc"><?php echo $description, $author; ?></td>
				<td class="action-links"><?php if ( !empty($action_links) )	echo implode(' | ', $action_links); ?></td>
			</tr>
			<?php
			}
			?>
		</tbody>
	</table>

	<div class="tablenav">
		<?php if ( $page_links )
				echo "\t\t<div class='tablenav-pages'>$page_links</div>"; ?>
		<br class="clear" />
	</div>

<?php
}

add_action('install_plugins_pre_plugin-information', 'install_plugin_information');

/**
 * Display plugin information in dialog box form.
 *
 * @since 2.7.0
 */
function install_plugin_information() {
	global $tab;

	$api = plugins_api('plugin_information', array('slug' => stripslashes( $_REQUEST['plugin'] ) ));

	if ( is_wp_error($api) )
		wp_die($api);

	$plugins_allowedtags = array('a' => array('href' => array(), 'title' => array(), 'target' => array()),
								'abbr' => array('title' => array()), 'acronym' => array('title' => array()),
								'code' => array(), 'pre' => array(), 'em' => array(), 'strong' => array(),
								'div' => array(), 'p' => array(), 'ul' => array(), 'ol' => array(), 'li' => array(),
								'h1' => array(), 'h2' => array(), 'h3' => array(), 'h4' => array(), 'h5' => array(), 'h6' => array(),
								'img' => array('src' => array(), 'class' => array(), 'alt' => array()));
	//Sanitize HTML
	foreach ( (array)$api->sections as $section_name => $content )
		$api->sections[$section_name] = wp_kses($content, $plugins_allowedtags);
	foreach ( array('version', 'author', 'requires', 'tested', 'homepage', 'downloaded', 'slug') as $key )
		$api->$key = wp_kses($api->$key, $plugins_allowedtags);

	$section = isset($_REQUEST['section']) ? stripslashes( $_REQUEST['section'] ) : 'description'; //Default to the Description tab, Do not translate, API returns English.
	if( empty($section) || ! isset($api->sections[ $section ]) )
		$section = array_shift( $section_titles = array_keys((array)$api->sections) );

	iframe_header( __('Plugin Install') );
	echo "<div id='$tab-header'>\n";
	echo "<ul id='sidemenu'>\n";
	foreach ( (array)$api->sections as $section_name => $content ) {

		$title = $section_name;
		$title = ucwords(str_replace('_', ' ', $title));

		$class = ( $section_name == $section ) ? ' class="current"' : '';
		$href = add_query_arg( array('tab' => $tab, 'section' => $section_name) );
		$href = clean_url($href);
		$san_title = attribute_escape(sanitize_title_with_dashes($title));
		echo "\t<li><a name='$san_title' target='' href='$href'$class>$title</a></li>\n";
	}
	echo "</ul>\n";
	echo "</div>\n";
	?>
	<div class="alignright fyi">
		<?php if ( ! empty($api->download_link) ) : ?>
		<p class="action-button">
		<?php
			//Default to a "new" plugin
			$type = 'install';
			//Check to see if this plugin is known to be installed, and has an update awaiting it.
			$update_plugins = get_option('update_plugins');
			if ( is_object( $update_plugins ) ) {
				foreach ( (array)$update_plugins->response as $file => $plugin ) {
					if ( $plugin->slug === $api->slug ) {
						$type = 'update_available';
						$update_file = $file;
						break;
					}
				}
			}
			if ( 'install' == $type && is_dir( WP_PLUGIN_DIR  . '/' . $api->slug ) ) {
				$installed_plugin = get_plugins('/' . $api->slug);
				if ( ! empty($installed_plugin) ) {
					$key = array_shift( $key = array_keys($installed_plugin) ); //Use the first plugin regardless of the name, Could have issues for multiple-plugins in one directory if they share different version numbers
					if ( version_compare($api->version, $installed_plugin[ $key ]['Version'], '>') ){
						$type = 'latest_installed';
					} elseif ( version_compare($api->version, $installed_plugin[ $key ]['Version'], '<') ) {
						$type = 'newer_installed';
						$newer_version = $installed_plugin[ $key ]['Version'];
					} else {
						//If the above update check failed, Then that probably means that the update checker has out-of-date information, force a refresh
						delete_option('update_plugins');
						$update_file = $api->slug . '/' . $key; //This code branch only deals with a plugin which is in a folder the same name as its slug, Doesnt support plugins which have 'non-standard' names
						$type = 'update_available';
					}
				}
			}

			switch ( $type ) :
				default:
				case 'install':
					if ( current_user_can('install_plugins') ) :
				?><a href="<?php echo wp_nonce_url(admin_url('plugin-install.php?tab=install&plugin=' . $api->slug), 'install-plugin_' . $api->slug) ?>" target="_parent"><?php _e('Install Now') ?></a><?php
					endif;
				break;
				case 'update_available':
					if ( current_user_can('update_plugins') ) :
						?><a href="<?php echo wp_nonce_url(admin_url('update.php?action=upgrade-plugin&plugin=' . $update_file), 'upgrade-plugin_' . $update_file) ?>" target="_parent"><?php _e('Install Update Now') ?></a><?php
					endif;
				break;
				case 'newer_installed':
					if ( current_user_can('install_plugins') || current_user_can('update_plugins') ) :
					?><a><?php printf(__('Newer Version (%s) Installed'), $newer_version) ?></a><?php
					endif;
				break;
				case 'latest_installed':
					if ( current_user_can('install_plugins') || current_user_can('update_plugins') ) :
					?><a><?php _e('Latest Version Installed') ?></a><?php
					endif;
				break;
			endswitch; ?>
		</p>
		<?php endif; ?>
		<h2 class="mainheader"><?php _e('FYI') ?></h2>
		<ul>
<?php if ( ! empty($api->version) ) : ?>
			<li><strong><?php _e('Version:') ?></strong> <?php echo $api->version ?></li>
<?php endif; if ( ! empty($api->author) ) : ?>
			<li><strong><?php _e('Author:') ?></strong> <?php echo links_add_target($api->author, '_blank') ?></li>
<?php endif; if ( ! empty($api->last_updated) ) : ?>
			<li><strong><?php _e('Last Updated:') ?></strong> <span title="<?php echo $api->last_updated ?>"><?php
							printf( __('%s ago'), human_time_diff(strtotime($api->last_updated)) ) ?></span></li>
<?php endif; if ( ! empty($api->requires) ) : ?>
			<li><strong><?php _e('Requires WordPress Version:') ?></strong> <?php printf(__('%s or higher'), $api->requires) ?></li>
<?php endif; if ( ! empty($api->tested) ) : ?>
			<li><strong><?php _e('Compatible up to:') ?></strong> <?php echo $api->tested ?></li>
<?php endif; if ( ! empty($api->downloaded) ) : ?>
			<li><strong><?php _e('Downloaded:') ?></strong> <?php printf(_n('%s time', '%s times', $api->downloaded), number_format_i18n($api->downloaded)) ?></li>
<?php endif; if ( ! empty($api->slug) ) : ?>
			<li><a target="_blank" href="http://wordpress.org/extend/plugins/<?php echo $api->slug ?>/"><?php _e('WordPress.org Plugin Page &#187;') ?></a></li>
<?php endif; if ( ! empty($api->homepage) ) : ?>
			<li><a target="_blank" href="<?php echo $api->homepage ?>"><?php _e('Plugin Homepage  &#187;') ?></a></li>
<?php endif; ?>
		</ul>
		<h2><?php _e('Average Rating') ?></h2>
		<div class="star-holder" title="<?php printf(_n('(based on %s rating)', '(based on %s ratings)', $api->num_ratings), number_format_i18n($api->num_ratings)); ?>">
			<div class="star star-rating" style="width: <?php echo attribute_escape($api->rating) ?>px"></div>
			<div class="star star5"><img src="<?php echo admin_url('images/star.gif'); ?>" alt="<?php _e('5 stars') ?>" /></div>
			<div class="star star4"><img src="<?php echo admin_url('images/star.gif'); ?>" alt="<?php _e('4 stars') ?>" /></div>
			<div class="star star3"><img src="<?php echo admin_url('images/star.gif'); ?>" alt="<?php _e('3 stars') ?>" /></div>
			<div class="star star2"><img src="<?php echo admin_url('images/star.gif'); ?>" alt="<?php _e('2 stars') ?>" /></div>
			<div class="star star1"><img src="<?php echo admin_url('images/star.gif'); ?>" alt="<?php _e('1 star') ?>" /></div>
		</div>
		<small><?php printf(_n('(based on %s rating)', '(based on %s ratings)', $api->num_ratings), number_format_i18n($api->num_ratings)); ?></small>
	</div>
	<div id="section-holder" class="wrap">
	<?php
		if ( !empty($api->tested) && version_compare( substr($GLOBALS['wp_version'], 0, strlen($api->tested)), $api->tested, '>') )
			echo '<div class="updated"><p>' . __('<strong>Warning:</strong> This plugin has <strong>not been tested</strong> with your current version of WordPress.') . '</p></div>';

		else if ( !empty($api->requires) && version_compare( substr($GLOBALS['wp_version'], 0, strlen($api->requires)), $api->requires, '<') )
			echo '<div class="updated"><p>' . __('<strong>Warning:</strong> This plugin has <strong>not been marked as compatible</strong> with your version of WordPress.') . '</p></div>';

		foreach ( (array)$api->sections as $section_name => $content ) {
			$title = $section_name;
			$title[0] = strtoupper($title[0]);
			$title = str_replace('_', ' ', $title);

			$content = links_add_base_url($content, 'http://wordpress.org/extend/plugins/' . $api->slug . '/');
			$content = links_add_target($content, '_blank');

			$san_title = attribute_escape(sanitize_title_with_dashes($title));

			$display = ( $section_name == $section ) ? 'block' : 'none';

			echo "\t<div id='section-{$san_title}' class='section' style='display: {$display};'>\n";
			echo "\t\t<h2 class='long-header'>$title</h2>";
			echo $content;
			echo "\t</div>\n";
		}
	echo "</div>\n";

	iframe_footer();
	exit;
}


add_action('install_plugins_do_upload', 'upload_plugin');
function upload_plugin() {

	if ( ! ( ( $uploads = wp_upload_dir() ) && false === $uploads['error'] ) )
		wp_die($uploads['error']);

	if ( !empty($_FILES) )
		$filename = $_FILES['pluginzip']['name'];
	else if ( isset($_GET['package']) )
		$filename = $_GET['package'];

	check_admin_referer('plugin-upload');

	echo '<div class="wrap">';
	echo '<h2>', sprintf( __('Installing Plugin from file: %s'), basename($filename) ), '</h2>';

	//Handle a newly uploaded file, Else assume it was
	if ( !empty($_FILES) ) {
		$filename = wp_unique_filename( $uploads['basedir'], $filename );
		$local_file = $uploads['basedir'] . '/' . $filename;

		// Move the file to the uploads dir
		if ( false === @ move_uploaded_file( $_FILES['pluginzip']['tmp_name'], $local_file) )
			wp_die( sprintf( __('The uploaded file could not be moved to %s.' ), $uploads['path']));
	} else {
		$local_file = $uploads['basedir'] . '/' . $filename;
	}

	do_plugin_install_local_package($local_file, $filename);
	echo '</div>';
}

add_action('install_plugins_install', 'install_plugin');

/**
 * Display plugin link and execute install.
 *
 * @since 2.7.0
 */
function install_plugin() {

	$plugin = isset($_REQUEST['plugin']) ? stripslashes( $_REQUEST['plugin'] ) : '';

	check_admin_referer('install-plugin_' . $plugin);
	$api = plugins_api('plugin_information', array('slug' => $plugin, 'fields' => array('sections' => false) ) ); //Save on a bit of bandwidth.

	if ( is_wp_error($api) )
		wp_die($api);

	echo '<div class="wrap">';
	echo '<h2>', sprintf( __('Installing Plugin: %s'), $api->name . ' ' . $api->version ), '</h2>';

	do_plugin_install($api->download_link, $api);
	echo '</div>';

}

/**
 * Retrieve plugin and install.
 *
 * @since 2.7.0
 *
 * @param string $download_url Download URL.
 * @param object $plugin_information Optional. Plugin information
 */
function do_plugin_install($download_url, $plugin_information = null) {
	global $wp_filesystem;

	if ( empty($download_url) ) {
		show_message( __('No plugin Specified') );
		return;
	}

	$plugin = isset($_REQUEST['plugin']) ? stripslashes( $_REQUEST['plugin'] ) : '';

	$url = 'plugin-install.php?tab=install';
	$url = add_query_arg(array('plugin' => $plugin, 'plugin_name' => stripslashes( $_REQUEST['plugin_name'] ), 'download_url' => stripslashes( $_REQUEST['download_url'] ) ), $url);

	$url = wp_nonce_url($url, 'install-plugin_' . $plugin);
	if ( false === ($credentials = request_filesystem_credentials($url)) )
		return;

	if ( ! WP_Filesystem($credentials) ) {
		request_filesystem_credentials($url, '', true); //Failed to connect, Error and request again
		return;
	}

	if ( $wp_filesystem->errors->get_error_code() ) {
		foreach ( $wp_filesystem->errors->get_error_messages() as $message )
			show_message($message);
		return;
	}

	$result = wp_install_plugin( $download_url, 'show_message' );

	if ( is_wp_error($result) ) {
		show_message($result);
		show_message( __('Installation Failed') );
	} else {
		show_message( sprintf(__('Successfully installed the plugin <strong>%s %s</strong>.'), $plugin_information->name, $plugin_information->version) );
		$plugin_file = $result;

		$install_actions = apply_filters('install_plugin_complete_actions', array(
			'activate_plugin' => '<a href="' . wp_nonce_url('plugins.php?action=activate&amp;plugin=' . $plugin_file, 'activate-plugin_' . $plugin_file) . '" title="' . attribute_escape(__('Activate this plugin')) . '" target="_parent">' . __('Activate Plugin') . '</a>',
			'plugins_page' => '<a href="' . admin_url('plugins.php') . '" title="' . attribute_escape(__('Goto plugins page')) . '" target="_parent">' . __('Return to Plugins page') . '</a>'
							), $plugin_information, $plugin_file);
		if ( ! empty($install_actions) )
			show_message('<strong>' . __('Actions:') . '</strong> ' . implode(' | ', (array)$install_actions));
	}
}

/**
 * Install a plugin from a local file.
 *
 * @since 2.7.0
 *
 * @param string $package Local Plugin zip
 * @param string $filename Optional. Original filename
 * @param object $plugin_information Optional. Plugin information
 */
function do_plugin_install_local_package($package, $filename = '') {
	global $wp_filesystem;

	if ( empty($package) ) {
		show_message( __('No plugin Specified') );
		return;
	}

	if ( empty($filename) )
		$filename = basename($package);

	$url = 'plugin-install.php?tab=upload';
	$url = add_query_arg(array('package' => $filename), $url);

	$url = wp_nonce_url($url, 'plugin-upload');
	if ( false === ($credentials = request_filesystem_credentials($url)) )
		return;

	if ( ! WP_Filesystem($credentials) ) {
		request_filesystem_credentials($url, '', true); //Failed to connect, Error and request again
		return;
	}

	if ( $wp_filesystem->errors->get_error_code() ) {
		foreach ( $wp_filesystem->errors->get_error_messages() as $message )
			show_message($message);
		return;
	}

	$result = wp_install_plugin_local_package( $package, 'show_message' );

	if ( is_wp_error($result) ) {
		show_message($result);
		show_message( __('Installation Failed') );
	} else {
		show_message( __('Successfully installed the plugin.') );
		$plugin_file = $result;

		$install_actions = apply_filters('install_plugin_complete_actions', array(
							'activate_plugin' => '<a href="' . wp_nonce_url('plugins.php?action=activate&amp;plugin=' . $plugin_file, 'activate-plugin_' . $plugin_file) . '" title="' . __('Activate this plugin') . '" target="_parent">' . __('Activate Plugin') . '</a>',
							'plugins_page' => '<a href="' . admin_url('plugins.php') . '" title="' . __('Goto plugins page') . '" target="_parent">' . __('Return to Plugins page') . '</a>'
							), array(), $plugin_file);
		if ( ! empty($install_actions) )
			show_message('<strong>' . __('Actions:') . '</strong> ' . implode(' | ', (array)$install_actions));
	}
}

/**
 * Install plugin.
 *
 * @since 2.7.0
 *
 * @param string $package
 * @param string $feedback Optional.
 * @return mixed.
 */
function wp_install_plugin($package, $feedback = '') {
	global $wp_filesystem;

	if ( !empty($feedback) )
		add_filter('install_feedback', $feedback);

	// Is a filesystem accessor setup?
	if ( ! $wp_filesystem || ! is_object($wp_filesystem) )
		WP_Filesystem();

	if ( ! is_object($wp_filesystem) )
		return new WP_Error('fs_unavailable', __('Could not access filesystem.'));

	if ( $wp_filesystem->errors->get_error_code() )
		return new WP_Error('fs_error', __('Filesystem error'), $wp_filesystem->errors);

	//Get the base plugin folder
	$plugins_dir = $wp_filesystem->wp_plugins_dir();
	if ( empty($plugins_dir) )
		return new WP_Error('fs_no_plugins_dir', __('Unable to locate WordPress Plugin directory.'));

	//And the same for the Content directory.
	$content_dir = $wp_filesystem->wp_content_dir();
	if( empty($content_dir) )
		return new WP_Error('fs_no_content_dir', __('Unable to locate WordPress Content directory (wp-content).'));

	$plugins_dir = trailingslashit( $plugins_dir );
	$content_dir = trailingslashit( $content_dir );

	if ( empty($package) )
		return new WP_Error('no_package', __('Install package not available.'));

	// Download the package
	apply_filters('install_feedback', sprintf(__('Downloading plugin package from %s'), $package));
	$download_file = download_url($package);

	if ( is_wp_error($download_file) )
		return new WP_Error('download_failed', __('Download failed.'), $download_file->get_error_message());

	$working_dir = $content_dir . 'upgrade/' . basename($package, '.zip');

	// Clean up working directory
	if ( $wp_filesystem->is_dir($working_dir) )
		$wp_filesystem->delete($working_dir, true);

	apply_filters('install_feedback', __('Unpacking the plugin package'));
	// Unzip package to working directory
	$result = unzip_file($download_file, $working_dir);

	// Once extracted, delete the package
	@unlink($download_file);

	if ( is_wp_error($result) ) {
		$wp_filesystem->delete($working_dir, true);
		return $result;
	}

	//Get a list of the directories in the working directory before we delete it, We need to know the new folder for the plugin
	$filelist = array_keys( $wp_filesystem->dirlist($working_dir) );

	if( $wp_filesystem->exists( $plugins_dir . $filelist[0] ) ) {
		$wp_filesystem->delete($working_dir, true);
		return new WP_Error('install_folder_exists', __('Folder already exists.'), $filelist[0] );
	}

	apply_filters('install_feedback', __('Installing the plugin'));
	// Copy new version of plugin into place.
	$result = copy_dir($working_dir, $plugins_dir);
	if ( is_wp_error($result) ) {
		$wp_filesystem->delete($working_dir, true);
		return $result;
	}

	//Get a list of the directories in the working directory before we delete it, We need to know the new folder for the plugin
	$filelist = array_keys( $wp_filesystem->dirlist($working_dir) );

	// Remove working directory
	$wp_filesystem->delete($working_dir, true);

	if( empty($filelist) )
		return false; //We couldnt find any files in the working dir, therefor no plugin installed? Failsafe backup.

	$folder = $filelist[0];
	$plugin = get_plugins('/' . $folder); //Ensure to pass with leading slash
	$pluginfiles = array_keys($plugin); //Assume the requested plugin is the first in the list

	//Return the plugin files name.
	return  $folder . '/' . $pluginfiles[0];
}

/**
 * Install plugin from local package
 *
 * @since 2.7.0
 *
 * @param string $package
 * @param string $feedback Optional.
 * @return mixed.
 */
function wp_install_plugin_local_package($package, $feedback = '') {
	global $wp_filesystem;

	if ( !empty($feedback) )
		add_filter('install_feedback', $feedback);

	// Is a filesystem accessor setup?
	if ( ! $wp_filesystem || ! is_object($wp_filesystem) )
		WP_Filesystem();

	if ( ! is_object($wp_filesystem) )
		return new WP_Error('fs_unavailable', __('Could not access filesystem.'));

	if ( $wp_filesystem->errors->get_error_code() )
		return new WP_Error('fs_error', __('Filesystem error'), $wp_filesystem->errors);

	//Get the base plugin folder
	$plugins_dir = $wp_filesystem->wp_plugins_dir();
	if ( empty($plugins_dir) )
		return new WP_Error('fs_no_plugins_dir', __('Unable to locate WordPress Plugin directory.'));

	//And the same for the Content directory.
	$content_dir = $wp_filesystem->wp_content_dir();
	if( empty($content_dir) )
		return new WP_Error('fs_no_content_dir', __('Unable to locate WordPress Content directory (wp-content).'));

	$plugins_dir = trailingslashit( $plugins_dir );
	$content_dir = trailingslashit( $content_dir );

	if ( empty($package) )
		return new WP_Error('no_package', __('Install package not available.'));

	$working_dir = $content_dir . 'upgrade/' . basename($package, '.zip');

	// Clean up working directory
	if ( $wp_filesystem->is_dir($working_dir) )
		$wp_filesystem->delete($working_dir, true);

	apply_filters('install_feedback', __('Unpacking the plugin package'));
	// Unzip package to working directory
	$result = unzip_file($package, $working_dir);

	// Once extracted, delete the package
	unlink($package);

	if ( is_wp_error($result) ) {
		$wp_filesystem->delete($working_dir, true);
		return $result;
	}

	//Get a list of the directories in the working directory before we delete it, We need to know the new folder for the plugin
	$filelist = array_keys( $wp_filesystem->dirlist($working_dir) );

	if( $wp_filesystem->exists( $plugins_dir . $filelist[0] ) ) {
		$wp_filesystem->delete($working_dir, true);
		return new WP_Error('install_folder_exists', __('Folder already exists.'), $filelist[0] );
	}

	apply_filters('install_feedback', __('Installing the plugin'));
	// Copy new version of plugin into place.
	$result = copy_dir($working_dir, $plugins_dir);
	if ( is_wp_error($result) ) {
		$wp_filesystem->delete($working_dir, true);
		return $result;
	}

	//Get a list of the directories in the working directory before we delete it, We need to know the new folder for the plugin
	$filelist = array_keys( $wp_filesystem->dirlist($working_dir) );

	// Remove working directory
	$wp_filesystem->delete($working_dir, true);

	if( empty($filelist) )
		return false; //We couldnt find any files in the working dir, therefor no plugin installed? Failsafe backup.

	$folder = $filelist[0];
	$plugin = get_plugins('/' . $folder); //Ensure to pass with leading slash
	$pluginfiles = array_keys($plugin); //Assume the requested plugin is the first in the list

	//Return the plugin files name.
	return  $folder . '/' . $pluginfiles[0];
}

?>