<?php
/**
 * WPSEO plugin file.
 *
 * @package WPSEO\Admin
 */

/**
 * Class to change or add WordPress dashboard widgets.
 */
class Yoast_Dashboard_Widget implements WPSEO_WordPress_Integration {

	/**
	 * Holds the cache transient key.
	 *
	 * @var string
	 */
	const CACHE_TRANSIENT_KEY = 'wpseo-dashboard-totals';

	/**
	 * Holds an instance of the admin asset manager.
	 *
	 * @var WPSEO_Admin_Asset_Manager
	 */
	protected $asset_manager;

	/**
	 * Holds the dashboard statistics.
	 *
	 * @var WPSEO_Statistics
	 */
	protected $statistics;

	/**
	 * Yoast_Dashboard_Widget constructor.
	 *
	 * @param WPSEO_Statistics|null $statistics WPSEO_Statistics instance.
	 */
	public function __construct( WPSEO_Statistics $statistics = null ) {
		if ( $statistics === null ) {
			$statistics = new WPSEO_Statistics();
		}

		$this->statistics    = $statistics;
		$this->asset_manager = new WPSEO_Admin_Asset_Manager();
	}

	/**
	 * Register WordPress hooks.
	 */
	public function register_hooks() {
		add_action( 'admin_enqueue_scripts', [ $this, 'enqueue_dashboard_assets' ] );
		add_action( 'admin_init', [ $this, 'queue_dashboard_widget' ] );
	}

	/**
	 * Adds the dashboard widget if it should be shown.
	 *
	 * @return void
	 */
	public function queue_dashboard_widget() {
		if ( $this->show_widget() ) {
			add_action( 'wp_dashboard_setup', [ $this, 'add_dashboard_widget' ] );
		}
	}

	/**
	 * Adds dashboard widget to WordPress.
	 */
	public function add_dashboard_widget() {
		add_filter( 'postbox_classes_dashboard_wpseo-dashboard-overview', [ $this, 'wpseo_dashboard_overview_class' ] );
		wp_add_dashboard_widget(
			'wpseo-dashboard-overview',
			/* translators: %s is the plugin name */
			sprintf( __( '%s Posts Overview', 'wordpress-seo' ), 'Yoast SEO' ),
			[ $this, 'display_dashboard_widget' ]
		);
	}

	/**
	 * Adds CSS classes to the dashboard widget.
	 *
	 * @param array $classes An array of postbox CSS classes.
	 *
	 * @return array
	 */
	public function wpseo_dashboard_overview_class( $classes ) {
		$classes[] = 'yoast wpseo-dashboard-overview';
		return $classes;
	}

	/**
	 * Displays the dashboard widget.
	 */
	public function display_dashboard_widget() {
		echo '<div id="yoast-seo-dashboard-widget"></div>';
	}

	/**
	 * Enqueues assets for the dashboard if the current page is the dashboard.
	 */
	public function enqueue_dashboard_assets() {
		if ( ! $this->is_dashboard_screen() ) {
			return;
		}

		wp_localize_script( WPSEO_Admin_Asset_Manager::PREFIX . 'dashboard-widget', 'wpseoDashboardWidgetL10n', $this->localize_dashboard_script() );
		$yoast_components_l10n = new WPSEO_Admin_Asset_Yoast_Components_L10n();
		$yoast_components_l10n->localize_script( WPSEO_Admin_Asset_Manager::PREFIX . 'dashboard-widget' );
		$this->asset_manager->enqueue_script( 'dashboard-widget' );
		$this->asset_manager->enqueue_style( 'wp-dashboard' );
	}

	/**
	 * Translates strings used in the dashboard widget.
	 *
	 * @return array The translated strings.
	 */
	public function localize_dashboard_script() {
		return [
			'feed_header'      => sprintf(
				/* translators: %1$s resolves to Yoast.com */
				__( 'Latest blog posts on %1$s', 'wordpress-seo' ),
				'Yoast.com'
			),
			'feed_footer'      => __( 'Read more like this on our SEO blog', 'wordpress-seo' ),
			'wp_version'       => substr( $GLOBALS['wp_version'], 0, 3 ) . '-' . ( is_plugin_active( 'classic-editor/classic-editor.php' ) ? '1' : '0' ),
			'php_version'      => PHP_MAJOR_VERSION . '.' . PHP_MINOR_VERSION,
		];
	}

	/**
	 * Checks if the current screen is the dashboard screen.
	 *
	 * @return bool Whether or not this is the dashboard screen.
	 */
	private function is_dashboard_screen() {
		$current_screen = get_current_screen();

		return ( $current_screen instanceof WP_Screen && $current_screen->id === 'dashboard' );
	}

	/**
	 * Returns true when the dashboard widget should be shown.
	 *
	 * @return bool
	 */
	private function show_widget() {
		$analysis_seo = new WPSEO_Metabox_Analysis_SEO();

		return $analysis_seo->is_enabled() && current_user_can( 'edit_posts' );
	}
}