curver/functions/kirki/modules/css/property/class-kirki-output-property-background-position.php

<?php
/**
 * Handles CSS output for background-position.
 *
 * @package     Kirki
 * @subpackage  Controls
 * @copyright   Copyright (c) 2019, Ari Stathopoulos (@aristath)
 * @license     https://opensource.org/licenses/MIT
 * @since       2.2.0
 */

/**
 * Output overrides.
 */
class Kirki_Output_Property_Background_Position extends Kirki_Output_Property {

	/**
	 * Modifies the value.
	 *
	 * @access protected
	 */
	protected function process_value() {
		$this->value = trim( $this->value );

		// If you use calc() there, I suppose you know what you're doing.
		// No need to process this any further, just exit.
		if ( false !== strpos( $this->value, 'calc' ) ) {
			return;
		}

		// If the value is initial or inherit, we don't need to do anything.
		// Just exit.
		if ( 'initial' === $this->value || 'inherit' === $this->value ) {
			return;
		}

		$x_dimensions = array( 'left', 'center', 'right' );
		$y_dimensions = array( 'top', 'center', 'bottom' );

		// If there's a space, we have an X and a Y value.
		if ( false !== strpos( $this->value, ' ' ) ) {
			$xy = explode( ' ', $this->value );

			$x = trim( $xy[0] );
			$y = trim( $xy[1] );

			// If x is not left/center/right, we need to sanitize it.
			if ( ! in_array( $x, $x_dimensions, true ) ) {
				$x = sanitize_text_field( $x );
			}
			if ( ! in_array( $y, $y_dimensions, true ) ) {
				$y = sanitize_text_field( $y );
			}
			$this->value = $x . ' ' . $y;
			return;
		}
		$x = 'center';
		foreach ( $x_dimensions as $x_dimension ) {
			if ( false !== strpos( $this->value, $x_dimension ) ) {
				$x = $x_dimension;
			}
		}
		$y = 'center';
		foreach ( $y_dimensions as $y_dimension ) {
			if ( false !== strpos( $this->value, $y_dimension ) ) {
				$y = $y_dimension;
			}
		}
		$this->value = $x . ' ' . $y;
	}
}