<?php
/** Maintenance request gate and WordPress administration. @package EscuderMaintenance */
namespace Escuder\Maintenance;

defined( 'ABSPATH' ) || exit;

final class Plugin {
	public function register() {
		// These hints cannot invalidate HTML already stored in an upstream cache.
		if ( Settings::enabled() ) {
			if ( ! defined( 'DONOTCACHEPAGE' ) ) {
				define( 'DONOTCACHEPAGE', true );
			}
		}
		add_action( 'init', array( $this, 'translations' ), -11000 );
		add_action( 'init', array( $this, 'enforce' ), -10000 );
		add_action( 'admin_menu', array( $this, 'menu' ) );
		add_action( 'admin_enqueue_scripts', array( $this, 'assets' ) );
		add_action( 'admin_post_escuder_maintenance_save', array( $this, 'save' ) );
		add_action( 'admin_post_escuder_maintenance_preview', array( $this, 'preview' ) );
		add_action( 'admin_notices', array( $this, 'notice' ) );
		add_action( 'admin_bar_menu', array( $this, 'admin_bar' ), 90 );
		add_filter( 'plugin_action_links_' . plugin_basename( ESCUDER_MAINTENANCE_FILE ), array( $this, 'links' ) );
	}

	public static function activate( $network_wide = false ) {
		if ( $network_wide && is_multisite() ) {
			wp_die( esc_html__( 'Activate Escuder Maintenance separately on each site. Network activation is not supported.', 'escuder-maintenance' ) );
		}
		$options = Settings::all();
		$options['enabled'] = 0;
		update_option( Settings::OPTION, $options, false );
	}

	public function translations() {
		$locale = determine_locale();
		if ( ! in_array( $locale, array( 'fr_FR', 'es_ES' ), true ) ) {
			return;
		}
		$official = WP_LANG_DIR . '/plugins/escuder-maintenance-' . $locale . '.mo';
		$php_pack = substr( $official, 0, -3 ) . '.l10n.php';
		$path = is_readable( $official ) || ( version_compare( get_bloginfo( 'version' ), '6.5', '>=' ) && is_readable( $php_pack ) ) ? $official : ESCUDER_MAINTENANCE_PATH . 'languages/escuder-maintenance-' . $locale . '.mo';
		load_textdomain( 'escuder-maintenance', $path, $locale );
	}

	public function allowed() {
		if ( current_user_can( 'manage_options' ) ) {
			return true;
		}
		$ip = Ip_Address::visitor();
		$options = Settings::all();
		return '' !== $ip && is_array( $options['allowed_ips'] ) && in_array( $ip, $options['allowed_ips'], true );
	}

	public function should_block() {
		global $pagenow;
		if ( ! Settings::enabled() || ( defined( 'WP_CLI' ) && WP_CLI ) || wp_doing_cron() ) {
			return false;
		}
		// Test the actual entry point, never a substring of the requested URL.
		$script = isset( $_SERVER['SCRIPT_FILENAME'] ) ? realpath( sanitize_text_field( wp_unslash( $_SERVER['SCRIPT_FILENAME'] ) ) ) : false;
		if ( 'wp-login.php' === $pagenow && $script && $script === realpath( ABSPATH . 'wp-login.php' ) ) {
			return false;
		}
		// Ordinary administration retains WordPress authentication and permissions.
		// admin-post and admin-ajax can expose public handlers and are gated as well.
		if ( is_admin() && ! wp_doing_ajax() && 'admin-post.php' !== $pagenow ) {
			return false;
		}
		return ! $this->allowed();
	}

	public function enforce() {
		if ( ! Settings::enabled() ) {
			return;
		}
		if ( ! headers_sent() ) {
			nocache_headers();
			header( 'Cache-Control: no-store, no-cache, must-revalidate, max-age=0, private', true );
		}
		if ( ! $this->should_block() ) {
			return;
		}
		$this->render( false );
		exit;
	}

	public function menu() {
		add_options_page( 'Escuder Maintenance', 'Escuder Maintenance', 'manage_options', 'escuder-maintenance', array( $this, 'settings_page' ) );
	}

	public function assets( $hook ) {
		if ( 'settings_page_escuder-maintenance' !== $hook ) {
			return;
		}
		wp_enqueue_media();
		wp_enqueue_style( 'escuder-maintenance-admin', ESCUDER_MAINTENANCE_URL . 'assets/admin.css', array(), ESCUDER_MAINTENANCE_VERSION );
		wp_enqueue_script( 'escuder-maintenance-admin', ESCUDER_MAINTENANCE_URL . 'assets/admin.js', array( 'media-views' ), ESCUDER_MAINTENANCE_VERSION, true );
		wp_localize_script( 'escuder-maintenance-admin', 'escuderMaintenance', array(
			'ip' => Ip_Address::visitor(),
			'logoTitle' => __( 'Choose a logo', 'escuder-maintenance' ),
			'logoButton' => __( 'Use this image', 'escuder-maintenance' ),
			'ipAdded' => __( 'IP address added. Save changes to apply it.', 'escuder-maintenance' ),
			'ipExists' => __( 'This IP address is already in the list.', 'escuder-maintenance' ),
		) );
	}

	public function settings_page() {
		if ( ! current_user_can( 'manage_options' ) ) {
			return;
		}
		$options = Settings::all();
		$preview_url = wp_nonce_url( admin_url( 'admin-post.php?action=escuder_maintenance_preview' ), 'escuder_maintenance_preview' );
		require ESCUDER_MAINTENANCE_PATH . 'views/settings.php';
	}

	public function save() {
		if ( ! current_user_can( 'manage_options' ) ) {
			wp_die( esc_html__( 'You are not allowed to change these settings.', 'escuder-maintenance' ), '', array( 'response' => 403 ) );
		}
		if ( ! isset( $_SERVER['REQUEST_METHOD'] ) || 'POST' !== $_SERVER['REQUEST_METHOD'] ) {
			wp_die( esc_html__( 'Use the settings form to save changes.', 'escuder-maintenance' ), '', array( 'response' => 405 ) );
		}
		check_admin_referer( 'escuder_maintenance_save' );
		$input = isset( $_POST['escuder_maintenance'] ) ? map_deep( wp_unslash( $_POST['escuder_maintenance'] ), 'sanitize_textarea_field' ) : null;
		$result = Settings::sanitize( $input );
		if ( is_wp_error( $result ) ) {
			wp_die( esc_html( $result->get_error_message() ), esc_html__( 'Settings not saved', 'escuder-maintenance' ), array( 'response' => 400, 'back_link' => true ) );
		}
		update_option( Settings::OPTION, $result, false );
		// Purging arbitrary server/CDN caches is deliberately left to their owner.
		wp_safe_redirect( add_query_arg( array( 'page' => 'escuder-maintenance', 'saved' => '1', '_wpnonce' => wp_create_nonce( 'escuder_maintenance_feedback' ) ), admin_url( 'options-general.php' ) ) );
		exit;
	}

	public function preview() {
		if ( ! current_user_can( 'manage_options' ) ) {
			wp_die( esc_html__( 'You are not allowed to preview this page.', 'escuder-maintenance' ), '', array( 'response' => 403 ) );
		}
		check_admin_referer( 'escuder_maintenance_preview' );
		$this->render( true );
		exit;
	}

	public function render( $preview ) {
		$options = Settings::all();
		nocache_headers();
		header( 'Cache-Control: no-store, no-cache, must-revalidate, max-age=0, private', true );
		status_header( $preview ? 200 : 503 );
		header( 'Content-Type: text/html; charset=' . get_option( 'blog_charset' ) );
		header( 'X-Robots-Tag: noindex, nofollow', true );
		header( 'X-Content-Type-Options: nosniff', true );
		if ( ! $preview ) {
			header( 'Retry-After: 3600', true );
		}
		// A HEAD response carries identical headers without an HTML body.
		if ( isset( $_SERVER['REQUEST_METHOD'] ) && 'HEAD' === $_SERVER['REQUEST_METHOD'] ) {
			return;
		}
		wp_enqueue_style( 'escuder-maintenance-page', ESCUDER_MAINTENANCE_URL . 'assets/maintenance.css', array(), ESCUDER_MAINTENANCE_VERSION );
		require ESCUDER_MAINTENANCE_PATH . 'views/maintenance.php';
	}

	public function notice() {
		if ( ! current_user_can( 'manage_options' ) || ! Settings::enabled() ) {
			return;
		}
		echo '<div class="notice notice-warning"><p><strong>Escuder Maintenance:</strong> ' . esc_html__( 'Maintenance is active. Visitors without an authorized IP cannot view the site.', 'escuder-maintenance' ) . ' <a href="' . esc_url( admin_url( 'options-general.php?page=escuder-maintenance' ) ) . '">' . esc_html__( 'Settings', 'escuder-maintenance' ) . '</a></p></div>';
	}

	public function admin_bar( $bar ) {
		if ( current_user_can( 'manage_options' ) && Settings::enabled() ) {
			$bar->add_node( array( 'id' => 'escuder-maintenance', 'title' => __( 'Maintenance active', 'escuder-maintenance' ), 'href' => admin_url( 'options-general.php?page=escuder-maintenance' ) ) );
		}
	}

	public function links( $links ) {
		array_unshift( $links, '<a href="' . esc_url( admin_url( 'options-general.php?page=escuder-maintenance' ) ) . '">' . esc_html__( 'Settings', 'escuder-maintenance' ) . '</a>' );
		return $links;
	}
}