<?php

if ( ! class_exists( 'ET_Core_VersionRollback' ) ):
/**
 * Handles version rollback.
 *
 * @since 3.10
 *
 * @private
 *
 * @package ET\Core\VersionRollback
 */
class ET_Core_VersionRollback {
	/**
	 * Product name.
	 *
	 * @var string
	 */
	protected $product_name = '';

	/**
	 * Product shortname.
	 *
	 * @var string
	 */
	protected $product_shortname = '';

	/**
	 * Current product version.
	 *
	 * @var string
	 */
	protected $product_version = '';

	/**
	 * Is rollback service enabled.
	 *
	 * @var bool
	 */
	protected $enabled = false;

	/**
	 * API Username.
	 *
	 * @var string
	 */
	protected $api_username = '';

	/**
	 * API Key.
	 *
	 * @var string
	 */
	protected $api_key = '';

	/**
	 * ET_Core_VersionRollback constructor.
	 *
	 * @since 3.10
	 *
	 * @param string $product_name
	 * @param string $product_shortname
	 * @param string $product_version
	 */
	public function __construct( $product_name, $product_shortname, $product_version ) {
		$this->product_name = sanitize_text_field( $product_name );
		$this->product_shortname = sanitize_text_field( $product_shortname );
		$this->product_version = sanitize_text_field( $product_version );

		if ( ! $options = get_site_option( 'et_automatic_updates_options' ) ) {
			$options = get_option( 'et_automatic_updates_options' );
		}

		$this->api_username = isset( $options['username'] ) ? sanitize_text_field( $options['username'] ) : '';
		$this->api_key = isset( $options['api_key'] ) ? sanitize_text_field( $options['api_key'] ) : '';
	}

	/**
	 * Enqueue assets.
	 *
	 * @since 3.10
	 */
	public function assets() {
		wp_enqueue_style( 'et-core-version-rollback', ET_CORE_URL . 'admin/css/version-rollback.css', array(
			'et-core-admin',
		), ET_CORE_VERSION );

		wp_enqueue_script( 'et-core-version-rollback', ET_CORE_URL . 'admin/js/version-rollback.js', array(
			'jquery',
			'jquery-ui-tabs',
			'jquery-form',
			'et-core-admin',
		), ET_CORE_VERSION );

		wp_localize_script( 'et-core-version-rollback', 'etCoreVersionRollbackI18n', array(
			'unknownError' => esc_html__( 'An unknown error has occurred. Please try again later.', 'et-core' ),
		) );
	}

	/**
	 * Get previous installed version, if any.
	 *
	 * @since 3.10
	 *
	 * @return string
	 */
	protected function _get_previous_installed_version() {
		return et_get_option( "{$this->product_shortname}_previous_installed_version", '' );
	}

	/**
	 * Set previous installed version.
	 *
	 * @since 3.10
	 *
	 * @param string $version
	 *
	 * @return void
	 */
	protected function _set_previous_installed_version( $version ) {
		et_update_option( "{$this->product_shortname}_previous_installed_version", sanitize_text_field( $version ) );
	}

	/**
	 * Get latest installed version, if any.
	 *
	 * @since 3.10
	 *
	 * @return string
	 */
	protected function _get_latest_installed_version() {
		return et_get_option( "{$this->product_shortname}_latest_installed_version", '' );
	}

	/**
	 * Set latest installed version.
	 *
	 * @since 3.10
	 *
	 * @param string $version
	 *
	 * @return void
	 */
	protected function _set_latest_installed_version( $version ) {
		et_update_option( "{$this->product_shortname}_latest_installed_version", sanitize_text_field( $version ) );
	}

	/**
	 * Check if the product has already been rolled back.
	 *
	 * @since 3.10
	 *
	 * @return bool
	 */
	protected function _is_rolled_back() {
		return version_compare( $this->_get_latest_installed_version(), $this->_get_previous_installed_version(), '<=' );
	}

	/**
	 * Get unique ajax action.
	 *
	 * @since 3.10
	 *
	 * @return string
	 */
	protected function _get_ajax_action() {
		return 'et_core_version_rollback';
	}

	/**
	 * Enable update rollback.
	 *
	 * @since 3.10
	 *
	 * @return void
	 */
	public function enable() {
		if ( $this->enabled ) {
			return;
		}

		$this->enabled = true;

		add_action( 'admin_enqueue_scripts', array( $this, 'assets' ) );
		add_action( 'wp_ajax_' . $this->_get_ajax_action(), array( $this, 'ajax_rollback' ) );
		// Update version number when theme is manually replaced.
		add_action( 'admin_init', array( $this, 'store_previous_version_number' ) );
		// Update version number when theme is activated.
		add_action( 'after_switch_theme', array( $this, 'store_previous_version_number' ) );
		// Update version number when theme is updated.
		add_action( 'upgrader_process_complete', array( $this, 'store_previous_version_number' ), 10, 0 );
	}

	/**
	 * Handle REST API requests to rollback.
	 *
	 * @since 3.10
	 *
	 * @return void
	 */
	public function ajax_rollback() {
		$nonce = isset( $_GET['nonce'] ) ? $_GET['nonce'] : '';

		if ( ! current_user_can( 'install_themes' ) ) {
			wp_send_json_error( array(
				'errorCode' => 'et_unknown',
				'error'     => esc_html__( 'You don\'t have sufficient permissions to access this page.', 'et-core' ),
			), 400 );
		}

		if ( ! wp_verify_nonce( $nonce, $this->_get_ajax_action() ) ) {
			wp_send_json_error( array(
				'errorCode' => 'et_unknown',
				'error'     => esc_html__( 'Security check failed. Please refresh and try again.', 'et-core' ),
			), 400 );
		}

		if ( $this->_is_rolled_back() ) {
			$error = '
				<p>
					' . et_get_safe_localization( sprintf(
						__( 'You\'re currently rolled back to <strong>Version %1$s</strong> from <strong>Version %2$s</strong>.', 'et-core' ),
						esc_html( $this->_get_latest_installed_version() ),
						esc_html( $this->_get_previous_installed_version() )
					) ) . '
				</p>
				<p>
					' . et_get_safe_localization( sprintf(
						__( 'Update to the latest version to unlock the full power of %1$s. <a href="%2$s" target="_blank">Learn more here</a>.', 'et-core' ),
						esc_html( $this->product_name ),
						esc_url( $this->_get_update_documentation_url() )
					) ) . '
				</p>
			';

			wp_send_json_error( array(
				'errorCode' => 'et_unknown',
				'error'     => $error,
			), 400 );
		}

		$success = $this->rollback();

		if ( is_wp_error( $success ) ) {
			$error = $success->get_error_message();
			if ( $success->get_error_code() === 'et_version_rollback_blacklisted' ) {
				$error = '
					<p>
						' . et_get_safe_localization( sprintf(
							__( 'For privacy and security reasons, you cannot rollback to <strong>Version %1$s</strong>.', 'et-core' ),
							esc_html( $this->_get_previous_installed_version() )
						) ) . '
					</p>
					<p>
						<a href="' . esc_url( $this->_get_update_documentation_url() ) . '" target="_blank">
							' . esc_html__( 'Learn more here.', 'et-core' ) . '
						</a>
					</p>
				';
			}

			wp_send_json_error( array(
				'errorIsUnrecoverable' => in_array( $success->get_error_code(), array( 'et_version_rollback_not_available', 'et_version_rollback_blacklisted' ) ),
				'errorCode'            => $success->get_error_code(),
				'error'                => $error,
			), 400 );
		}

		wp_send_json_success();
	}

	/**
	 * Execute a version rollback.
	 *
	 * @since 3.10
	 *
	 * @return bool|WP_Error
	 */
	public function rollback() {
		// Load versions before rollback so they are not affected.
		$previous_version = $this->_get_previous_installed_version();
		$latest_version = $this->_get_latest_installed_version();

		$api = new ET_Core_API_ElegantThemes( $this->api_username, $this->api_key );
		$available = $api->is_product_available( $this->product_name, $previous_version );

		if ( is_wp_error( $available ) ) {
			return $available;
		}

		$download_url = $api->get_download_url( $this->product_name, $previous_version );

		// Buffer and discard output as upgrader classes still output content even if the upgrader skin is silent.
		ob_start();
		$result = $this->_install_theme( $download_url );
		ob_end_clean();

		if ( is_wp_error( $result ) ) {
			return $result;
		}

		if ( true !== $result ) {
			return new WP_Error( 'et_unknown', esc_html__( 'An unknown error has occurred. Please try again later.', 'et-core' ) );
		}

		// Swap version numbers after a successful rollback.
		$this->_set_previous_installed_version( $latest_version );
		$this->_set_latest_installed_version( $previous_version );
	}

	/**
	 * Install a theme overwriting it if it already exists.
	 * Copied from Theme_Upgrader::install() due to lack of control over the clear_desination argument.
	 *
	 * @see Theme_Upgrader::install() @ WordPress 4.9.4
	 *
	 * @since 3.10
	 *
	 * @param string $package
	 *
	 * @return bool|WP_Error
	 */
	protected function _install_theme( $package ) {
		require_once( ABSPATH . 'wp-admin/includes/class-wp-upgrader.php' );
		$upgrader = new Theme_Upgrader( new ET_Core_LIB_SilentThemeUpgraderSkin() );

		$defaults = array(
			'clear_update_cache' => true,
		);
		$parsed_args = wp_parse_args( array(), $defaults );

		$upgrader->init();
		$upgrader->install_strings();

		add_filter('upgrader_source_selection', array( $upgrader, 'check_package' ) );
		add_filter('upgrader_post_install', array( $upgrader, 'check_parent_theme_filter' ), 10, 3 );
		if ( $parsed_args['clear_update_cache'] ) {
			// Clear cache so wp_update_themes() knows about the new theme.
			add_action( 'upgrader_process_complete', 'wp_clean_themes_cache', 9, 0 );
		}

		$upgrader->run( array(
			'package'           => $package,
			'destination'       => get_theme_root(),
			'clear_destination' => true, // Overwrite theme.
			'clear_working'     => true,
			'hook_extra'        => array(
				'type'              => 'theme',
				'action'            => 'install',
			),
		) );

		remove_action( 'upgrader_process_complete', 'wp_clean_themes_cache', 9 );
		remove_filter( 'upgrader_source_selection', array( $upgrader, 'check_package' ) );
		remove_filter( 'upgrader_post_install', array( $upgrader, 'check_parent_theme_filter' ) );

		if ( ! $upgrader->result || is_wp_error( $upgrader->result ) ) {
			return $upgrader->result;
		}

		// Refresh the Theme Update information.
		wp_clean_themes_cache( $parsed_args['clear_update_cache'] );

		return true;
	}

	/**
	 * Get update documentation url for the product.
	 *
	 * @since 3.10
	 *
	 * @return string
	 */
	protected function _get_update_documentation_url() {
		return "https://www.elegantthemes.com/documentation/{$this->product_shortname}/update-{$this->product_shortname}/";
	}

	/**
	 * Return ePanel option.
	 *
	 * @since 3.10
	 *
	 * @return array
	 */
	public function get_epanel_option() {
		return array(
			'name'            => esc_html__( 'Version Rollback', ET_CORE_VERSION ),
			'id'              => 'et_version_rollback',
			'type'            => 'callback_function',
			'function_name'   => array( $this, 'render_epanel_option' ),
			'desc'            => et_get_safe_localization( __( '<em>Before you can receive product updates, you must first authenticate your Elegant Themes subscription. To do this, you need to enter both your Elegant Themes Username and your Elegant Themes API Key into the Updates Tab in your theme and plugin settings. To locate your API Key, <a href="https://www.elegantthemes.com/members-area/api/" target="_blank">log in</a> to your Elegant Themes account and navigate to the <strong>Account > API Key</strong> page. <a href="http://www.elegantthemes.com/gallery/divi/documentation/update/" target="_blank">Learn more here</a></em>. If you still get this message, please make sure that your Username and API Key have been entered correctly', ET_CORE_VERSION ) ),
		);
	}

	/**
	 * Render ePanel option.
	 *
	 * @since 3.10
	 *
	 * @return void
	 */
	public function render_epanel_option() {
		$previous = $this->_get_previous_installed_version();
		$modal_renderer = array( $this, 'render_epanel_no_previous_version_modal' );

		if ( ! empty( $previous ) ) {
			$modal_renderer = array( $this, 'render_epanel_confirm_rollback_modal' );

			if ( $this->_is_rolled_back() ) {
				$modal_renderer = array( $this, 'render_epanel_already_rolled_back_modal' );
			}
		}

		add_action( 'admin_footer', $modal_renderer );
		?>
		<button type="button" class="et-button et-button--simple" data-et-core-modal=".et-core-version-rollback-modal">
			<?php esc_html_e( 'Rollback to the previous version', 'et-core' ); ?>
		</button>
		<?php
	}

	/**
	 * Render ePanel warning modal when no previous supported version has been used.
	 *
	 * @since 3.10
	 *
	 * @return void
	 */
	public function render_epanel_no_previous_version_modal() {
		?>
		<div class="et-core-modal-overlay et-core-form et-core-version-rollback-modal et-core-modal-actionless">
			<div class="et-core-modal">
				<div class="et-core-modal-header">
					<h3 class="et-core-modal-title">
						<?php esc_html_e( 'Version Rollback', 'et-core' ); ?>
					</h3>
					<a href="#" class="et-core-modal-close" data-et-core-modal="close"></a>
				</div>
				<div id="et-core-version-rollback-modal-content">
					<div class="et-core-modal-content">
						<p>
							<?php
							printf(
								esc_html__( 'The previously used version of %1$s does not support version rollback.', 'et-core' ),
								$this->product_name
							);
							?>
						</p>
					</div>
				</div>
			</div>
		</div>
		<?php
	}

	/**
	 * Render ePanel confirmation modal for rollback.
	 *
	 * @since 3.10
	 *
	 * @return void
	 */
	public function render_epanel_confirm_rollback_modal() {
		$action = $this->_get_ajax_action();
		$url = add_query_arg( array(
			'action'  => $action,
			'nonce'   => wp_create_nonce( $action ),
		), admin_url( 'admin-ajax.php' ) );
		?>
		<div class="et-core-modal-overlay et-core-form et-core-version-rollback-modal">
			<div class="et-core-modal">
				<div class="et-core-modal-header">
					<h3 class="et-core-modal-title">
						<?php esc_html_e( 'Version Rollback', 'et-core' ); ?>
					</h3>
					<a href="#" class="et-core-modal-close" data-et-core-modal="close"></a>
				</div>
				<div id="et-core-version-rollback-modal-content">
					<div class="et-core-modal-content">
						<p>
							<?php
							echo et_get_safe_localization( sprintf(
								__( 'You\'ll be rolled back to <strong>Version %1$s</strong> from the current <strong>Version %2$s</strong>.', 'et-core' ),
								esc_html( $this->_get_previous_installed_version() ),
								esc_html( $this->_get_latest_installed_version() )
							) );
							?>
						</p>
						<p>
							<?php
							echo et_get_safe_localization( sprintf(
								__( 'Rolling back will reinstall the previous version of %1$s. You will be able to update to the latest version at any time. <a href="%2$s" target="_blank">Learn more here</a>.', 'et-core' ),
								esc_html( $this->product_name ),
								esc_url( $this->_get_update_documentation_url() )
							) );
							?>
						</p>
						<p>
							<strong>
								<?php esc_html_e( 'Make sure you have a full site backup before proceeding.', 'et-core' ); ?>
							</strong>
						</p>
					</div>
					<a class="et-core-modal-action et-core-version-rollback-confirm" href="<?php echo esc_url( $url ); ?>">
						<?php esc_html_e( 'Rollback to the previous version', 'et-core' ); ?>
					</a>
				</div>
			</div>
		</div>
		<?php
	}

	/**
	 * Render ePanel warning modal when a rollback has already been done.
	 *
	 * @since 3.10
	 *
	 * @return void
	 */
	public function render_epanel_already_rolled_back_modal() {
		?>
		<div class="et-core-modal-overlay et-core-form et-core-version-rollback-modal">
			<div class="et-core-modal">
				<div class="et-core-modal-header">
					<h3 class="et-core-modal-title">
						<?php esc_html_e( 'Version Rollback', 'et-core' ); ?>
					</h3>
					<a href="#" class="et-core-modal-close" data-et-core-modal="close"></a>
				</div>
				<div id="et-core-version-rollback-modal-content">
					<div class="et-core-modal-content">
						<p>
							<?php
							echo et_get_safe_localization( sprintf(
								__( 'You\'re currently rolled back to <strong>Version %1$s</strong> from <strong>Version %2$s</strong>.', 'et-core' ),
								esc_html( $this->_get_latest_installed_version() ),
								esc_html( $this->_get_previous_installed_version() )
							) );
							?>
						</p>
						<p>
							<?php
							echo et_get_safe_localization( sprintf(
								__( 'Update to the latest version to unlock the full power of %1$s. <a href="%2$s" target="_blank">Learn more here</a>.', 'et-core' ),
								esc_html( $this->product_name ),
								esc_url( $this->_get_update_documentation_url() )
							) );
							?>
						</p>
					</div>
					<a class="et-core-modal-action" href="<?php echo esc_url( admin_url( 'update-core.php' ) ); ?>">
						<?php esc_html_e( 'Update to the Latest Version', 'et-core' ); ?>
					</a>
				</div>
			</div>
		</div>
		<?php
	}

	/**
	 * Store latest and previous installed version.
	 *
	 * @since 3.10
	 *
	 * @return void;
	 */
	public function store_previous_version_number() {
		$previous_installed_version = $this->_get_previous_installed_version();
		$latest_installed_version = $this->_get_latest_installed_version();

		// Get the theme version since the files may have changed but
		// we are still executing old code from memory.
		$theme_version = et_get_theme_version();

		if ( $latest_installed_version === $theme_version ) {
			return;
		}

		if ( empty( $latest_installed_version ) ) {
			$latest_installed_version = $theme_version;
		}

		if ( version_compare( $theme_version, $latest_installed_version, '!=') ) {
			$previous_installed_version = $latest_installed_version;
			$latest_installed_version = $theme_version;
		}

		$this->_set_previous_installed_version( $previous_installed_version );
		$this->_set_latest_installed_version( $latest_installed_version );
	}
}
endif;
