Add notifyQuantityChanges functions

assets/js/data/cart/notify-quantity-changes.ts

@@ -0,0 +1,122 @@
+/**
+ * External dependencies
+ */
+import { Cart } from '@woocommerce/types';
+import { dispatch } from '@wordpress/data';
+import { __, sprintf } from '@wordpress/i18n';
+
+const notifyIfQuantityLimitsChanged = ( oldCart: Cart, newCart: Cart ) => {
+	newCart.items.forEach( ( cartItem ) => {
+		const oldCartItem = oldCart.items.find( ( item ) => {
+			return item.key === cartItem.key;
+		} );
+
+		// If getCartData has not finished resolving, then this is the first load. We should also check for min/max
+		// quantity discrepancies here.
+		const isFirstLoad = oldCart.items.length === 0;
+
+		// Item has been removed, we don't need to do any more checks.
+		if ( ! oldCartItem && ! isFirstLoad ) {
+			return;
+		}
+
+		const quantityAboveMax =
+			cartItem.quantity > cartItem.quantity_limits.maximum;
+		const quantityBelowMin =
+			cartItem.quantity < cartItem.quantity_limits.minimum;
+
+		// If the quantity is still within the constraints, then we don't need to show any notice, this is because
+		// QuantitySelector will not automatically update the value.
+		if ( ! quantityAboveMax && ! quantityBelowMin ) {
+			return;
+		}
+
+		if ( quantityBelowMin ) {
+			dispatch( 'core/notices' ).createInfoNotice(
+				sprintf(
+					/* translators: %1$s is the name of the item, %2$d is the quantity of the item. */
+					__(
+						'The quantity of "%1$s" has been increased to %2$d. This is the minimum required quantity.',
+						'woo-gutenberg-products-block'
+					),
+					cartItem.name,
+					cartItem.quantity_limits.minimum
+				),
+				{
+					context: 'wc/cart',
+					type: 'snackbar',
+					id: `${ cartItem.key }-quantity-update`,
+				}
+			);
+			return;
+		}
+		dispatch( 'core/notices' ).createInfoNotice(
+			sprintf(
+				/* translators: %1$s is the name of the item, %2$d is the quantity of the item. */
+				__(
+					'The quantity of "%1$s" has been decreased to %2$d. This is the maximum allowed quantity.',
+					'woo-gutenberg-products-block'
+				),
+				cartItem.name,
+				cartItem.quantity_limits.maximum
+			),
+			{
+				context: 'wc/cart',
+				type: 'snackbar',
+				id: `${ cartItem.key }-quantity-update`,
+			}
+		);
+	} );
+};
+
+const notifyIfQuantityChanged = (
+	oldCart: Cart,
+	newCart: Cart,
+	cartItemsPendingQuantity: string[]
+) => {
+	newCart.items.forEach( ( cartItem ) => {
+		if ( cartItemsPendingQuantity.includes( cartItem.key ) ) {
+			return;
+		}
+		const oldCartItem = oldCart.items.find( ( item ) => {
+			return item.key === cartItem.key;
+		} );
+		if ( ! oldCartItem ) {
+			return;
+		}
+		if ( cartItem.key === oldCartItem.key ) {
+			if ( cartItem.quantity !== oldCartItem.quantity ) {
+				dispatch( 'core/notices' ).createInfoNotice(
+					sprintf(
+						/* translators: %1$s is the name of the item, %2$d is the quantity of the item. */
+						__(
+							'The quantity of %1$s has been updated to %2$d.',
+							'woo-gutenberg-products-block'
+						),
+						cartItem.name,
+						cartItem.quantity
+					),
+					{
+						context: 'wc/cart',
+						type: 'snackbar',
+						id: `${ cartItem.key }-quantity-update`,
+					}
+				);
+			}
+			return cartItem;
+		}
+	} );
+};
+
+/**
+ * This function is used to notify the user when the quantity of an item in the cart has changed. It checks both the
+ * item's quantity and quantity limits.
+ */
+export const notifyQuantityChanges = (
+	oldCart: Cart,
+	newCart: Cart,
+	cartItemsPendingQuantity: string[]
+) => {
+	notifyIfQuantityLimitsChanged( oldCart, newCart );
+	notifyIfQuantityChanged( oldCart, newCart, cartItemsPendingQuantity );
+};