Add custom order fields drop-down to custom fields metabox under HPOS

plugins/woocommerce/changelog/fix-44029

@@ -0,0 +1,4 @@
+Significance: patch
+Type: add
+
+Add used meta keys dropdown in HPOS custom fields metabox.

plugins/woocommerce/client/legacy/css/admin.scss

@@ -2786,6 +2786,17 @@ ul.wc_coupon_list_block {
 	}
 }
 
+#order_custom #postcustomstuff {
+	.add-custom-field {
+		padding: 12px 8px 8px;
+	}
+
+	.submit {
+		border: 0 none;
+		float: none;
+	}
+}
+
 #side-sortables #woocommerce-order-downloads {
 	.buttons,
 	.select2-container {

plugins/woocommerce/src/Internal/Admin/Orders/MetaBoxes/CustomMetaBox.php

@@ -1,12 +1,12 @@
 <?php
 /**
  * Meta box to edit and add custom meta values for an order.
  */
 
 namespace Automattic\WooCommerce\Internal\Admin\Orders\MetaBoxes;
 
-use WC_Data_Store;
-use WC_Meta_Data;
+use Automattic\WooCommerce\Internal\DataStores\CustomMetaDataStore;
+use Automattic\WooCommerce\Internal\DataStores\Orders\OrdersTableDataStoreMeta;
 use WC_Order;
 use WP_Ajax_Response;
 
@@ -92,16 +92,44 @@
 	 * Compute keys to display in autofill when adding new meta key entry in custom meta box.
 	 * Currently, returns empty keys, will be implemented after caching is merged.
 	 *
-	 * @param array|null         $keys Keys to display in autofill.
-	 * @param \WP_Post|\WC_Order $order Order object.
+	 * @param mixed              $deprecated Unused argument. For backwards compatibility.
+	 * @param \WP_Post|\WC_Order $order      Order object.
 	 *
-	 * @return array|mixed Array of keys to display in autofill.
+	 * @return array Array of keys to display in autofill.
 	 */
-	public function order_meta_keys_autofill( $keys, $order ) {
-		if ( is_a( $order, \WC_Order::class ) ) {
+	public function order_meta_keys_autofill( $deprecated, $order ) {
+		if ( ! is_a( $order, \WC_Order::class ) ) {
 			return array();
 		}
 
+		/**
+		 * Filters values for the meta key dropdown in the Custom Fields meta box.
+		 *
+		 * Compatibility filter for `postmeta_form_keys` filter.
+		 *
+		 * @since 6.9.0
+		 *
+		 * @param array|null $keys Pre-defined meta keys to be used in place of a postmeta query. Default null.
+		 * @param \WC_Order  $order The current post object.
+		 */
+		$keys = apply_filters( 'postmeta_form_keys', null, $order );
+		if ( null === $keys || ! is_array( $keys ) ) {
+			/**
+			 * Compatibility filter for 'postmeta_form_limit', which filters the number of custom fields to retrieve
+			 * for the drop-down in the Custom Fields meta box.
+			 *
+			 * @since 8.8.0
+			 *
+			 * @param int $limit Number of custom fields to retrieve. Default 30.
+			 */
+			$limit = apply_filters( 'postmeta_form_limit', 30 );
+			$keys  = wc_get_container()->get( OrdersTableDataStoreMeta::class )->get_meta_keys( $limit );
+		}
+
+		if ( $keys ) {
+			natcasesort( $keys );
+		}
+
 		return $keys;
 	}
 
@@ -116,17 +144,6 @@
 		$meta_key_input_id = 'metakeyselect';
 
 		$keys = $this->order_meta_keys_autofill( null, $order );
-		/**
-		 * Filters values for the meta key dropdown in the Custom Fields meta box.
-		 *
-		 * Compatibility filter for `postmeta_form_keys` filter.
-		 *
-		 * @since 6.9.0
-		 *
-		 * @param array|null $keys Pre-defined meta keys to be used in place of a postmeta query. Default null.
-		 * @param \WC_Order  $order The current post object.
-		 */
-		$keys = apply_filters( 'postmeta_form_keys', $keys, $order );
 		?>
 		<p><strong><?php esc_html_e( 'Add New Custom Field:', 'woocommerce' ); ?></strong></p>
 		<table id="newmeta">
@@ -145,43 +162,42 @@
 							<option value="#NONE#"><?php esc_html_e( '&mdash; Select &mdash;', 'woocommerce' ); ?></option>
 							<?php
 							foreach ( $keys as $key ) {
-								if ( is_protected_meta( $key, 'post' ) || ! current_user_can( 'edit_others_shop_order', $order->get_id() ) ) {
+								if ( is_protected_meta( $key, 'post' ) || ! current_user_can( 'edit_others_shop_orders' ) ) {
 									continue;
 								}
 								echo "\n<option value='" . esc_attr( $key ) . "'>" . esc_html( $key ) . '</option>';
 							}
 							?>
 						</select>
-						<input class="hide-if-js" type="text" id="metakeyinput" name="metakeyinput" value="" />
-						<a href="#postcustomstuff" class="hide-if-no-js" onclick="jQuery('#metakeyinput, #metakeyselect, #enternew, #cancelnew').toggle();return false;">
-							<span id="enternew"><?php esc_html_e( 'Enter new', 'woocommerce' ); ?></span>
-							<span id="cancelnew" class="hidden"><?php esc_html_e( 'Cancel', 'woocommerce' ); ?></span></a>
+						<input class="hidden" type="text" id="metakeyinput" name="metakeyinput" value="" aria-label="<?php esc_attr_e( 'New custom field name', 'woocommerce' ); ?>" />
+						<button type="button" id="newmeta-button" class="button button-small hide-if-no-js" onclick="jQuery('#metakeyinput, #metakeyselect, #enternew, #cancelnew').toggleClass('hidden');jQuery('#metakeyinput, #metakeyselect').filter(':visible').trigger('focus');">
+						<span id="enternew"><?php esc_html_e( 'Enter new', 'woocommerce' ); ?></span>
+						<span id="cancelnew" class="hidden"><?php esc_html_e( 'Cancel', 'woocommerce' ); ?></span>
 					<?php } else { ?>
 						<input type="text" id="metakeyinput" name="metakeyinput" value="" />
 					<?php } ?>
 				</td>
-				<td><textarea id="metavalue" name="metavalue" rows="2" cols="25"></textarea></td>
+				<td><textarea id="metavalue" name="metavalue" rows="2" cols="25"></textarea>
+				<?php wp_nonce_field( 'add-meta', '_ajax_nonce-add-meta', false ); ?>
+				</td>
 			</tr>
-
-			<tr><td colspan="2">
-					<div class="submit">
-						<?php
-						submit_button(
-							__( 'Add Custom Field', 'woocommerce' ),
-							'',
-							'addmeta',
-							false,
-							array(
-								'id'            => 'newmeta-submit',
-								'data-wp-lists' => 'add:the-list:newmeta',
-							)
-						);
-						?>
-					</div>
-					<?php wp_nonce_field( 'add-meta', '_ajax_nonce-add-meta', false ); ?>
-				</td></tr>
 			</tbody>
 		</table>
+
+		<div class="submit add-custom-field">
+			<?php
+			submit_button(
+				__( 'Add Custom Field', 'woocommerce' ),
+				'',
+				'addmeta',
+				false,
+				array(
+					'id'            => 'newmeta-submit',
+					'data-wp-lists' => 'add:the-list:newmeta',
+				)
+			);
+			?>
+		</div>
 		<?php
 	}
 
@@ -218,17 +234,20 @@
 		$order_id = (int) $_POST['order_id'] ?? 0;
 		$order    = $this->verify_order_edit_permission_for_ajax( $order_id );
 
-		if ( isset( $_POST['metakeyselect'] ) && '#NONE#' === $_POST['metakeyselect'] && empty( $_POST['metakeyinput'] ) ) {
+		$select_meta_key = trim( sanitize_text_field( wp_unslash( $_POST['metakeyselect'] ?? '' ) ) );
+		$input_meta_key  = trim( sanitize_text_field( wp_unslash( $_POST['metakeyinput'] ?? '' ) ) );
+
+		if ( empty( $_POST['meta'] ) && in_array( $select_meta_key, array( '', '#NONE#' ), true ) && ! $input_meta_key ) {
 			wp_die( 1 );
 		}
 
-		if ( isset( $_POST['metakeyinput'] ) ) { // add meta.
-			$meta_key   = sanitize_text_field( wp_unslash( $_POST['metakeyinput'] ) );
+		if ( ! empty( $_POST['meta'] ) ) { // update.
+			$meta = wp_unslash( $_POST['meta'] ); // phpcs:ignore WordPress.Security.ValidatedSanitizedInput.InputNotSanitized -- sanitization done below in array_walk.
+			$this->handle_update_meta( $order, $meta );
+		} else { // add meta.
 			$meta_value = sanitize_text_field( wp_unslash( $_POST['metavalue'] ?? '' ) );
+			$meta_key   = $input_meta_key ? $input_meta_key : $select_meta_key;
 			$this->handle_add_meta( $order, $meta_key, $meta_value );
-		} else { // update.
-			$meta = wp_unslash( $_POST['meta'] ?? array() ); // phpcs:ignore WordPress.Security.ValidatedSanitizedInput.InputNotSanitized -- sanitization done below in array_walk.
-			$this->handle_update_meta( $order, $meta );
 		}
 	}
 

plugins/woocommerce/src/Internal/DataStores/CustomMetaDataStore.php

@@ -232,4 +232,35 @@ public function get_metadata_by_key( &$object, string $meta_key ) {
 		return $meta;
 	}
 
+	/**
+	 * Returns distinct meta keys in use.
+	 *
+	 * @since 8.8.0
+	 *
+	 * @param int    $limit           Maximum number of meta keys to return. Defaults to 100.
+	 * @param string $order           Order to use for the results. Either 'ASC' or 'DESC'. Defaults to 'ASC'.
+	 * @param bool   $include_private Whether to include private meta keys in the results. Defaults to FALSE.
+	 * @return string[]
+	 */
+	public function get_meta_keys( $limit = 100, $order = 'ASC', $include_private = false ) {
+		global $wpdb;
+
+		$db_info = $this->get_db_info();
+
+		$query = "SELECT DISTINCT meta_key FROM {$db_info['table']} ";
+
+		if ( ! $include_private ) {
+			$query .= $wpdb->prepare( 'WHERE meta_key NOT LIKE %s ', $wpdb->esc_like( '_' ) . '%' );
+		}
+
+		$order  = in_array( strtoupper( $order ), array( 'ASC', 'DESC' ), true ) ? $order : 'ASC';
+		$query .= 'ORDER BY meta_key ' . $order . ' ';
+
+		if ( $limit ) {
+			$query .= $wpdb->prepare( 'LIMIT %d ', $limit );
+		}
+
+		return $wpdb->get_col( $query ); // phpcs:ignore WordPress.DB.PreparedSQL.NotPrepared -- $query is prepared.
+	}
+
 }