<?php
/**
 * License socket.
 *
 * @package ALPEG\Forms
 */

namespace ALPEG\Forms;

defined( 'ABSPATH' ) || exit;

/**
 * On purpose, the plugin contains NO connection to a license server.
 * It only provides the interface (enter key, show status) and clearly
 * defined filters. A separate license module talks to the ALPEG LMS.
 * The page is only shown once such a module is installed.
 */
class License {

	const OPTION = 'alpeg_forms_license_key';

	/**
	 * Is a license module connected?
	 *
	 * @return bool
	 */
	public static function has_module() {
		return has_filter( 'alpeg_forms_license_activate' ) || has_filter( 'alpeg_forms_license_status' );
	}

	/**
	 * Stored key.
	 *
	 * @return string
	 */
	public static function key() {
		return (string) get_option( self::OPTION, '' );
	}

	/**
	 * Current status (provided by the license module).
	 *
	 * @return array{state:string,message:string}
	 */
	public static function status() {
		$default = array(
			'state'   => self::key() ? 'unknown' : 'none',
			'message' => '',
		);
		/**
		 * License status for display.
		 *
		 * @param array  $status state: none|unknown|active|grace|expired|invalid, message: free text.
		 * @param string $key    Stored key.
		 */
		$status = apply_filters( 'alpeg_forms_license_status', $default, self::key() );
		return wp_parse_args( is_array( $status ) ? $status : array(), $default );
	}

	/**
	 * Handle the "License" form (admin-post).
	 */
	public static function handle_save() {
		if ( ! current_user_can( 'manage_options' ) ) {
			wp_die( esc_html__( 'You are not allowed to do this.', 'alpeg-forms' ), 403 );
		}
		check_admin_referer( 'alpeg_forms_license' );

		$do     = isset( $_POST['af_license_action'] ) ? sanitize_key( wp_unslash( $_POST['af_license_action'] ) ) : 'activate';
		$notice = array(
			'type'    => 'success',
			'message' => '',
		);

		if ( 'deactivate' === $do ) {
			/**
			 * Deactivate the license on the license server.
			 *
			 * @param array|\WP_Error|null $result Result.
			 * @param string               $key    Key.
			 */
			$result = apply_filters( 'alpeg_forms_license_deactivate', null, self::key() );
			if ( is_wp_error( $result ) ) {
				$notice = array(
					'type'    => 'error',
					'message' => $result->get_error_message(),
				);
			} else {
				delete_option( self::OPTION );
				$notice['message'] = __( 'The license has been deactivated on this website.', 'alpeg-forms' );
			}
		} else {
			$key = isset( $_POST['af_license_key'] ) ? trim( sanitize_text_field( wp_unslash( $_POST['af_license_key'] ) ) ) : '';
			update_option( self::OPTION, $key, false );

			/**
			 * Activate the license on the license server.
			 * Return array( 'message' => '...' ) on success or WP_Error.
			 *
			 * @param array|\WP_Error|null $result Result.
			 * @param string               $key    Key.
			 * @param string               $domain Domain of this website.
			 */
			$result = apply_filters( 'alpeg_forms_license_activate', null, $key, wp_parse_url( home_url(), PHP_URL_HOST ) );

			if ( is_wp_error( $result ) ) {
				$notice = array(
					'type'    => 'error',
					'message' => $result->get_error_message(),
				);
			} elseif ( null === $result ) {
				$notice = array(
					'type'    => 'info',
					'message' => __( 'Key saved. The Pro version is not available yet – as soon as it is released, your key will be used automatically.', 'alpeg-forms' ),
				);
			} else {
				$notice['message'] = isset( $result['message'] ) ? (string) $result['message'] : __( 'License activated. Enjoy Pro!', 'alpeg-forms' );
			}
		}

		set_transient( 'alpeg_forms_license_notice_' . get_current_user_id(), $notice, 60 );
		wp_safe_redirect( admin_url( 'admin.php?page=alpeg-forms-license' ) );
		exit;
	}

	/**
	 * Render the "License" page.
	 */
	public static function render_page() {
		$status = self::status();
		$key    = self::key();
		$notice = get_transient( 'alpeg_forms_license_notice_' . get_current_user_id() );
		delete_transient( 'alpeg_forms_license_notice_' . get_current_user_id() );

		$labels = array(
			'none'    => array( __( 'No license', 'alpeg-forms' ), 'neutral' ),
			'unknown' => array( __( 'Key saved', 'alpeg-forms' ), 'neutral' ),
			'active'  => array( __( 'Active', 'alpeg-forms' ), 'good' ),
			'grace'   => array( __( 'Expired – grace period', 'alpeg-forms' ), 'warn' ),
			'expired' => array( __( 'Expired', 'alpeg-forms' ), 'warn' ),
			'invalid' => array( __( 'Invalid', 'alpeg-forms' ), 'bad' ),
		);
		$label  = isset( $labels[ $status['state'] ] ) ? $labels[ $status['state'] ] : $labels['unknown'];
		?>
		<div class="wrap alpeg-admin">
			<h1><?php esc_html_e( 'License', 'alpeg-forms' ); ?></h1>

			<?php if ( is_array( $notice ) && $notice['message'] ) : ?>
				<div class="notice notice-<?php echo esc_attr( $notice['type'] ); ?> is-dismissible"><p><?php echo esc_html( $notice['message'] ); ?></p></div>
			<?php endif; ?>

			<div class="alpeg-card">
				<p class="alpeg-license-state">
					<?php esc_html_e( 'Status:', 'alpeg-forms' ); ?>
					<span class="alpeg-pill alpeg-pill--<?php echo esc_attr( $label[1] ); ?>"><?php echo esc_html( $label[0] ); ?></span>
				</p>
				<?php if ( $status['message'] ) : ?>
					<p><?php echo esc_html( $status['message'] ); ?></p>
				<?php endif; ?>

				<form method="post" action="<?php echo esc_url( admin_url( 'admin-post.php' ) ); ?>">
					<?php wp_nonce_field( 'alpeg_forms_license' ); ?>
					<input type="hidden" name="action" value="alpeg_forms_license">
					<label for="af_license_key" class="alpeg-label"><?php esc_html_e( 'Activation key', 'alpeg-forms' ); ?></label>
					<div class="alpeg-inline">
						<input type="text" class="regular-text code" id="af_license_key" name="af_license_key" value="<?php echo esc_attr( $key ); ?>" autocomplete="off" spellcheck="false">
						<button type="submit" class="button button-primary" name="af_license_action" value="activate"><?php esc_html_e( 'Activate', 'alpeg-forms' ); ?></button>
						<?php if ( $key ) : ?>
							<button type="submit" class="button" name="af_license_action" value="deactivate"><?php esc_html_e( 'Deactivate', 'alpeg-forms' ); ?></button>
						<?php endif; ?>
					</div>
				</form>

				<?php if ( ! self::has_module() ) : ?>
					<p class="description"><?php esc_html_e( 'All features of the free version can be used without a license. The Pro version with payments, webhooks and CRM connections is coming.', 'alpeg-forms' ); ?></p>
				<?php endif; ?>
			</div>
		</div>
		<?php
	}
}