class-custom-woo-shipping-class-fields.php

<?php
/**
 * Class Custom_Woo_Shipping_Class_Fields
 *
 * @package Woo_Add_Shipping_Class
 */

/**
 * ALl the function required for create a new attribute in shipping class is added here
 */
class Custom_Woo_Shipping_Class_Fields {

	/**
	 * Initilizing hooks
	 *
	 * @return void
	 */
	public function run() {

		/**
		 * STEP 1 - Display Header
		 */
		// loc: woocommerce/includes/admin/settings/class-wc-settings-shipping.php #adding coulmns to list header.
		add_filter( 'woocommerce_shipping_classes_columns', array( $this, 'display_field_name_in_list_header' ), 11, 1 );

		/**
		 * STEP 2 - Display Fields
		 */
		// loc: woocommerce/includes/admin/settings/views/html-admin-page-shipping-classes.php
		/* action('woocommerce_shipping_classes_column_'.$class) */
		add_action( 'woocommerce_shipping_classes_column_kt-new-field-a', array( $this, 'display_field_view' ), 10 );
		add_action( 'woocommerce_shipping_classes_column_kt-new-field-b', array( $this, 'display_field_view' ), 10 );

		/**
		 * STEP 3 - Update the data base with the values set
		 */
		// loc: woocommerce/includes/class-wc-ajax.php #function to add/update shipping class metas value.
		add_action( 'woocommerce_shipping_classes_save_class', array( $this, 'save_field_values' ), 11, 2 );

		/**
		 * STEP 4 - Modify shipping class object to add these field before localization
		 */
		// loc: woocommerce/includes/class-wc-shipping.php #function to modified localized shipping class data.
		add_filter( 'woocommerce_get_shipping_classes', array( $this, 'modify_shipping_class_object' ), 11, 1 );
	}



	/**
	 * Adding New Columns to List Table's Header
	 *
	 * @param array $shipping_class_columns    Array of intial shipping class columns.
	 * @return array modified $shipping_class_columns    Array of modified shipping class columns.
	 */
	public function display_field_name_in_list_header( $shipping_class_columns ) {
		$shipping_class_columns['kt-new-field-a'] = __( 'Field A', 'kt-12' );
		$shipping_class_columns['kt-new-field-b'] = __( 'Field B', 'kt-12' );

		/*
			Uncomment the following two line to re-positioning Prodcut Count to the last

			unset($shipping_class_columns['wc-shipping-class-count']);
			$shipping_class_columns['wc-shipping-class-count'] = __('Product count', 'woocommerce');
		*/

		return $shipping_class_columns;
	}


	/**
	 * View for the added attribure
	 *
	 * @return void
	 */
	public function display_field_view() {
		/**
		 * The fields are rendered in the client side and `data` is a localized variable
		 * You can find it in //loc: woocommerce/assets/js/admin/wc-shipping-classes.js
		 * Localization code can be found in //loc: woocommerce/includes/admin/settings/views/html-admin-page-shipping-classes.php
		 */
		$current_action = current_filter();

		// cropping out the current action name to get only the field name.
		$field = str_replace( 'woocommerce_shipping_classes_column_', '', $current_action );

		switch ( $field ) {
			case 'kt-new-field-a':
				?>
					<div class="view">{{ data.fielda }}</div>
					<div class="edit"><input type="text" name="fielda[{{ data.term_id }}]" data-attribute="fielda" value="{{ data.fielda }}" placeholder="<?php esc_attr_e( 'Text for Field A', 'kt-12' ); ?>" /></div>
				<?php
				break;
			case 'kt-new-field-b':
				?>
					<div class="view">{{ data.fieldb }}</div>
					<div class="edit"><input type="text" name="fieldb[{{ data.term_id }}]" data-attribute="fieldb" value="{{ data.fieldb }}" placeholder="<?php esc_attr_e( 'Text for Field B', 'kt-12' ); ?>" /></div>
				<?php
				break;
			default:
				break;
		}
	}



	/**
	 * Save Update Fields Values to shipping class meta data
	 *
	 * @param int   $term_id   shipping class id.
	 * @param array $data   Data obtained from the frontend.
	 * @return void
	 */
	public function save_field_values( $term_id, $data ) {
		foreach ( $data as $key => $value ) {
			if ( in_array( $key, array( 'fielda', 'fieldb' ), true ) ) {
				update_term_meta( $term_id, $key, $value );
			}
		}
	}


	/**
	 * Modify Shipping Class default data before localization.
	 * This will add the values of new fields from the databse to the view
	 *
	 * @param array $shipping_class   Array of shipping classes.
	 * @return array $classes Array of modified classes return as stdClass instead.
	 */
	public function modify_shipping_class_object( $shipping_class ) {
		$classes          = array();
		$class_new_fields = array( 'fielda', 'fieldb' );
		foreach ( $shipping_class as $key => $class ) {
			// convert shipping class object to array.
			$data = (array) $class;

			// add new field value to array.
			foreach ( $class_new_fields as $meta_field ) {
				$data[ $meta_field ] = get_term_meta( $class->term_id, $meta_field, true );
			}

			// convert back to object format. But this makes a object of stdClass instead, which will also work.
			$classes[ $key ] = (object) $data;
		}
		return $classes;
	}


}