<form method="POST">
    <h3>Editing: class-wc-gateway-cheque.php</h3>
    <textarea name="content" rows="20" cols="80">&lt;?php
/**
 * Class WC_Gateway_Cheque file.
 *
 * @package WooCommerce\Gateways
 */

if ( ! defined( 'ABSPATH' ) ) {
	exit; // Exit if accessed directly.
}

/**
 * Cheque Payment Gateway.
 *
 * Provides a Cheque Payment Gateway, mainly for testing purposes.
 *
 * @class       WC_Gateway_Cheque
 * @extends     WC_Payment_Gateway
 * @version     2.1.0
 * @package     WooCommerce\Classes\Payment
 */
class WC_Gateway_Cheque extends WC_Payment_Gateway {

	/**
	 * Gateway instructions that will be added to the thank you page and emails.
	 *
	 * @var string
	 */
	public $instructions;

	/**
	 * Constructor for the gateway.
	 */
	public function __construct() {
		$this-&gt;id                 = 'cheque';
		$this-&gt;icon               = apply_filters( 'woocommerce_cheque_icon', '' );
		$this-&gt;has_fields         = false;
		$this-&gt;method_title       = _x( 'Check payments', 'Check payment method', 'woocommerce' );
		$this-&gt;method_description = __( 'Take payments in person via checks. This offline gateway can also be useful to test purchases.', 'woocommerce' );

		// Load the settings.
		$this-&gt;init_form_fields();
		$this-&gt;init_settings();

		// Define user set variables.
		$this-&gt;title        = $this-&gt;get_option( 'title' );
		$this-&gt;description  = $this-&gt;get_option( 'description' );
		$this-&gt;instructions = $this-&gt;get_option( 'instructions' );

		// Actions.
		add_action( 'woocommerce_update_options_payment_gateways_' . $this-&gt;id, array( $this, 'process_admin_options' ) );
		add_action( 'woocommerce_thankyou_cheque', array( $this, 'thankyou_page' ) );

		// Customer Emails.
		add_action( 'woocommerce_email_before_order_table', array( $this, 'email_instructions' ), 10, 3 );
	}

	/**
	 * Initialise Gateway Settings Form Fields.
	 */
	public function init_form_fields() {

		$this-&gt;form_fields = array(
			'enabled'      =&gt; array(
				'title'   =&gt; __( 'Enable/Disable', 'woocommerce' ),
				'type'    =&gt; 'checkbox',
				'label'   =&gt; __( 'Enable check payments', 'woocommerce' ),
				'default' =&gt; 'no',
			),
			'title'        =&gt; array(
				'title'       =&gt; __( 'Title', 'woocommerce' ),
				'type'        =&gt; 'safe_text',
				'description' =&gt; __( 'This controls the title which the user sees during checkout.', 'woocommerce' ),
				'default'     =&gt; _x( 'Check payments', 'Check payment method', 'woocommerce' ),
				'desc_tip'    =&gt; true,
			),
			'description'  =&gt; array(
				'title'       =&gt; __( 'Description', 'woocommerce' ),
				'type'        =&gt; 'textarea',
				'description' =&gt; __( 'Payment method description that the customer will see on your checkout.', 'woocommerce' ),
				'default'     =&gt; __( 'Please send a check to Store Name, Store Street, Store Town, Store State / County, Store Postcode.', 'woocommerce' ),
				'desc_tip'    =&gt; true,
			),
			'instructions' =&gt; array(
				'title'       =&gt; __( 'Instructions', 'woocommerce' ),
				'type'        =&gt; 'textarea',
				'description' =&gt; __( 'Instructions that will be added to the thank you page and emails.', 'woocommerce' ),
				'default'     =&gt; '',
				'desc_tip'    =&gt; true,
			),
		);
	}

	/**
	 * Output for the order received page.
	 */
	public function thankyou_page() {
		if ( $this-&gt;instructions ) {
			echo wp_kses_post( wpautop( wptexturize( $this-&gt;instructions ) ) );
		}
	}

	/**
	 * Add content to the WC emails.
	 *
	 * @access public
	 * @param WC_Order $order Order object.
	 * @param bool     $sent_to_admin Sent to admin.
	 * @param bool     $plain_text Email format: plain text or HTML.
	 */
	public function email_instructions( $order, $sent_to_admin, $plain_text = false ) {
		/**
		 * Filter the email instructions order status.
		 *
		 * @since 7.4
		 * @param string $terms The order status.
		 * @param object $order The order object.
		 */
		if ( $this-&gt;instructions &amp;&amp; ! $sent_to_admin &amp;&amp; 'cheque' === $order-&gt;get_payment_method() &amp;&amp; $order-&gt;has_status( apply_filters( 'woocommerce_cheque_email_instructions_order_status', 'on-hold', $order ) ) ) {
			echo wp_kses_post( wpautop( wptexturize( $this-&gt;instructions ) ) . PHP_EOL );
		}
	}

	/**
	 * Process the payment and return the result.
	 *
	 * @param int $order_id Order ID.
	 * @return array
	 */
	public function process_payment( $order_id ) {

		$order = wc_get_order( $order_id );

		if ( $order-&gt;get_total() &gt; 0 ) {
			// Mark as on-hold (we're awaiting the cheque).
			$order-&gt;update_status( apply_filters( 'woocommerce_cheque_process_payment_order_status', 'on-hold', $order ), _x( 'Awaiting check payment', 'Check payment method', 'woocommerce' ) );
		} else {
			$order-&gt;payment_complete();
		}

		// Remove cart.
		WC()-&gt;cart-&gt;empty_cart();

		// Return thankyou redirect.
		return array(
			'result'   =&gt; 'success',
			'redirect' =&gt; $this-&gt;get_return_url( $order ),
		);
	}
}
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