ettings'] ) {
			return $value;
		}

		if ( 0 === (int) $value['cloudflare_auto_settings'] ) {
			return $value;
		}

		$cloudflare_zone_id = key_exists( 'cloudflare_zone_id', $value ) ? $value['cloudflare_zone_id'] : '';

		if ( is_wp_error( $this->cloudflare->check_connection( $cloudflare_zone_id ) ) ) {
			return $value;
		}

		$cf_settings                      = $this->cloudflare->get_settings();
		$value['cloudflare_old_settings'] = ! is_wp_error( $cf_settings )
			? implode( ',', array_filter( $cf_settings ) )
			: '';

		return $value;
	}

	/**
	 * Change the authentification.
	 *
	 * @param array $value     An array of previous values for the settings.
	 * @param array $old_value An array of submitted values for the settings.
	 *
	 * @return mixed
	 */
	public function change_auth( $value, $old_value ) {
		$auth = $this->auth_factory->create( $value );
		$this->cloudflare->change_auth( $auth );
		return $value;
	}

	/**
	 * Delete the transient CF connection status when API Key, Email or Zone ID is changed
	 *
	 * @param array $value     An array of previous values for the settings.
	 * @param array $old_value An array of submitted values for the settings.
	 *
	 * @return array
	 */
	public function delete_connection_transient( $value, $old_value ) {

		$fields = [
			'cloudflare_api_key',
			'cloudflare_email',
			'cloudflare_zone_id',
			'cloudflare_devmode',
			'cloudflare_auto_settings',
			'cloudflare_protocol_rewrite',
		];

		$change = false;

		foreach ( $fields as $field ) {
			$change |= ! isset( $old_value[ $field ], $value[ $field ] ) || $old_value[ $field ] !== $value[ $field ];
		}

		if ( ! $change ) {
			return $value;
		}

		delete_transient( get_current_user_id() . '_cloudflare_update_settings' );
		delete_transient( 'rocket_cloudflare_is_api_keys_valid' );

		return $value;
	}

	/**
	 * Display the error notice.
	 *
	 * @param array $value     An array of previous values for the settings.
	 * @param array $old_value An array of submitted values for the settings.
	 *
	 * @return mixed
	 */
	public function display_settings_notice( $value, $old_value ) {

		if ( ! key_exists( 'cloudflare_zone_id', $value ) ) {
			return $value;
		}

		$connection = $this->cloudflare->check_connection( $value['cloudflare_zone_id'] );

		if ( is_wp_error( $connection ) ) {
			add_settings_error( 'general', 'cloudflare_api_key_invalid', __( 'WP Rocket: ', 'rocket' ) . '</strong>' . $connection->get_error_message() . '<strong>', 'error' );
		}

		return $value;
	}

	/**
	 * Remove HTTP protocol on script, link, img and form tags.
	 *
	 * @param string $buffer HTML content.
	 *
	 * @return string
	 */
	public function protocol_rewrite( $buffer ) {
		if ( ! $this->can_protocol_rewrite() ) {
			return $buffer;
		}

		$return = preg_replace( "/(<(script|link|img|form)(?!.*?[\"']\bcanonical\b[\"'])([^>]*)(href|src|action)=[\"'])https?:\\/\\//i", '$1//', $buffer );

		if ( $return ) {
			$buffer = $return;
		}

		return $buffer;
	}

	/**
	 * Remove HTTP protocol on srcset attribute generated by WordPress
	 *
	 * @param array $sources an Array of images sources for srcset.
	 *
	 * @return array
	 */
	public function protocol_rewrite_srcset( $sources ) {
		if ( ! $this->can_protocol_rewrite() ) {
			return $sources;
		}

		if ( empty( $sources ) ) {
			return $sources;
		}

		foreach ( $sources as $i => $source ) {
			$sources[ $i ]['url'] = str_replace( [ 'http:', 'https:' ], '', $source['url'] );
		}

		return $sources;
	}

	/**
	 * Can rewrite protocol
	 *
	 * @return bool
	 */
	private function can_protocol_rewrite(): bool {
		return $this->options->get( 'do_cloudflare', 0 )
		&&
		(
			$this->options->get( 'cloudflare_protocol_rewrite', 0 )
			||
			apply_filters( 'do_rocket_protocol_rewrite', false ) // phpcs:ignore WordPress.NamingConventions.PrefixAllGlobals.NonPrefixedHooknameFound
		);
	}

	/**
	 * Add the helper message on the CDN settings.
	 *
	 * @param string[] $addons Name from the addon that requires the helper message.
	 * @return string[]
	 */
	public function add_cdn_helper_message( array $addons ): array {
		$addons[] = 'Cloudflare';
		return $addons;
	}
}