WP_Plugin_Install_List_Table::prepare_items()

	public function prepare_items() {
		include( ABSPATH . 'wp-admin/includes/plugin-install.php' );

		global $tabs, $tab, $paged, $type, $term;

		wp_reset_vars( array( 'tab' ) );

		$paged = $this->get_pagenum();

		$per_page = 30;

		// These are the tabs which are shown on the page
		$tabs = array();

		if ( 'search' === $tab ) {
			$tabs['search'] = __( 'Search Results' );
		}
		$tabs['popular']    = _x( 'Popular', 'Plugin Installer' );
		$tabs['categories'] = _x( 'Categories', 'Plugin Installer' );
		if ( current_user_can( 'upload_plugins' ) ) {
			// No longer a real tab. Here for filter compatibility.
			// Gets skipped in get_views().
			$tabs['upload'] = __( 'Upload Plugin' );
		}

		$nonmenu_tabs = array( 'plugin-information' ); // Valid actions to perform which do not have a Menu item.

		/**
		 * Filters the tabs shown on the Plugin Install screen.
		 *
		 * @since WP-2.7.0
		 *
		 * @param array $tabs The tabs shown on the Plugin Install screen.
		 *                    Defaults include 'popular' and 'categories'.
		 *
		 */
		$tabs = apply_filters( 'install_plugins_tabs', $tabs );

		/**
		 * Filters tabs not associated with a menu item on the Plugin Install screen.
		 *
		 * @since WP-2.7.0
		 *
		 * @param array $nonmenu_tabs The tabs that don't have a Menu item on the Plugin Install screen.
		 */
		$nonmenu_tabs = apply_filters( 'install_plugins_nonmenu_tabs', $nonmenu_tabs );

		// If a non-valid menu tab has been selected, And it's not a non-menu action.
		if ( empty( $tab ) || ( !isset( $tabs[ $tab ] ) && !in_array( $tab, (array) $nonmenu_tabs ) ) )
			$tab = key( $tabs );

		$installed_plugins = $this->get_installed_plugins();

		$args = array(
			'page' => $paged,
			'per_page' => $per_page,
			'fields' => array(
				'last_updated' => true,
				'icons' => true,
				'active_installs' => true
			),
			// Send the locale and installed plugin slugs to the API so it can provide context-sensitive results.
			'locale' => get_user_locale(),
			'installed_plugins' => array_keys( $installed_plugins ),
		);

		switch ( $tab ) {
			case 'search':
				$type = isset( $_REQUEST['type'] ) ? wp_unslash( $_REQUEST['type'] ) : 'term';
				$term = isset( $_REQUEST['s'] ) ? wp_unslash( $_REQUEST['s'] ) : '';

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

				break;

			case 'popular':
				$args['browse'] = $tab;
				break;

			default:
				$args = false;
				break;
		}

		/**
		 * Filters API request arguments for each Plugin Install screen tab.
		 *
		 * The dynamic portion of the hook name, `$tab`, refers to the plugin install tabs.
		 * Default tabs include 'popular', 'categories', and 'upload'.
		 *
		 * @since WP-3.7.0
		 *
		 * @param array|bool $args Plugin Install API arguments.
		 */
		$args = apply_filters( "install_plugins_table_api_args_{$tab}", $args );

		if ( !$args )
			return;

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

		if ( is_wp_error( $api ) ) {
			$this->error = $api;
			return;
		}

		$this->items = $api->plugins;

		if ( $this->orderby ) {
			uasort( $this->items, array( $this, 'order_callback' ) );
		}

		$this->set_pagination_args( array(
			'total_items' => $api->info['results'],
			'per_page' => $args['per_page'],
		) );

		if ( isset( $api->info['groups'] ) ) {
			$this->groups = $api->info['groups'];
		}

		if ( $installed_plugins ) {
			$js_plugins = array_fill_keys(
				array( 'all', 'search', 'active', 'inactive', 'recently_activated', 'mustuse', 'dropins' ),
				array()
			);

			$js_plugins['all'] = array_values( wp_list_pluck( $installed_plugins, 'plugin' ) );
			$upgrade_plugins   = wp_filter_object_list( $installed_plugins, array( 'upgrade' => true ), 'and', 'plugin' );

			if ( $upgrade_plugins ) {
				$js_plugins['upgrade'] = array_values( $upgrade_plugins );
			}

			wp_localize_script( 'updates', '_wpUpdatesItemCounts', array(
				'plugins' => $js_plugins,
				'totals'  => wp_get_update_data(),
			) );
		}
	}