hod ) {
					$params['arg_options'] = array_diff_key(
						$params['arg_options'],
						array(
							'required' => '',
							'default'  => '',
						)
					);
				}

				$endpoint_args[ $field_id ] = array_merge( $endpoint_args[ $field_id ], $params['arg_options'] );
			}
		}

		return $endpoint_args;
	}

	/**
	 * Force all schema properties to be readonly.
	 *
	 * @param array $properties Schema.
	 * @return array Updated schema.
	 */
	protected function force_schema_readonly( $properties ) {
		return array_map(
			function( $property ) {
				$property['readonly'] = true;
				if ( isset( $property['items']['properties'] ) ) {
					$property['items']['properties'] = $this->force_schema_readonly( $property['items']['properties'] );
				}
				return $property;
			},
			$properties
		);
	}

	/**
	 * Returns consistent currency schema used across endpoints for prices.
	 *
	 * @return array
	 */
	protected function get_store_currency_properties() {
		return [
			'currency_code'               => [
				'description' => __( 'Currency code (in ISO format) for returned prices.', 'woocommerce' ),
				'type'        => 'string',
				'context'     => [ 'view', 'edit' ],
				'readonly'    => true,
			],
			'currency_symbol'             => [
				'description' => __( 'Currency symbol for the currency which can be used to format returned prices.', 'woocommerce' ),
				'type'        => 'string',
				'context'     => [ 'view', 'edit' ],
				'readonly'    => true,
			],
			'currency_minor_unit'         => [
				'description' => __( 'Currency minor unit (number of digits after the decimal separator) for returned prices.', 'woocommerce' ),
				'type'        => 'integer',
				'context'     => [ 'view', 'edit' ],
				'readonly'    => true,
			],
			'currency_decimal_separator'  => array(
				'description' => __( 'Decimal separator for the currency which can be used to format returned prices.', 'woocommerce' ),
				'type'        => 'string',
				'context'     => array( 'view', 'edit' ),
				'readonly'    => true,
			),
			'currency_thousand_separator' => array(
				'description' => __( 'Thousand separator for the currency which can be used to format returned prices.', 'woocommerce' ),
				'type'        => 'string',
				'context'     => array( 'view', 'edit' ),
				'readonly'    => true,
			),
			'currency_prefix'             => array(
				'description' => __( 'Price prefix for the currency which can be used to format returned prices.', 'woocommerce' ),
				'type'        => 'string',
				'context'     => array( 'view', 'edit' ),
				'readonly'    => true,
			),
			'currency_suffix'             => array(
				'description' => __( 'Price prefix for the currency which can be used to format returned prices.', 'woocommerce' ),
				'type'        => 'string',
				'context'     => array( 'view', 'edit' ),
				'readonly'    => true,
			),
		];
	}

	/**
	 * Adds currency data to an array of monetary values.
	 *
	 * @param array $values Monetary amounts.
	 * @return array Monetary amounts with currency data appended.
	 */
	protected function prepare_currency_response( $values ) {
		return $this->extend->get_formatter( 'currency' )->format( $values );
	}

	/**
	 * Convert monetary values from WooCommerce to string based integers, using
	 * the smallest unit of a currency.
	 *
	 * @param string|float $amount Monetary amount with decimals.
	 * @param int          $decimals Number of decimals the amount is formatted with.
	 * @param int          $rounding_mode Defaults to the PHP_ROUND_HALF_UP constant.
	 * @return string      The new amount.
	 */
	protected function prepare_money_response( $amount, $decimals = 2, $rounding_mode = PHP_ROUND_HALF_UP ) {
		return $this->extend->get_formatter( 'money' )->format(
			$amount,
			[
				'decimals'      => $decimals,
				'rounding_mode' => $rounding_mode,
			]
		);
	}

	/**
	 * Prepares HTML based content, such as post titles and content, for the API response.
	 *
	 * @param string|array $response Data to format.
	 * @return string|array Formatted data.
	 */
	protected function prepare_html_response( $response ) {
		return $this->extend->get_formatter( 'html' )->format( $response );
	}
}