[Woo POS] Coupons: Show an error and CTA to proceed without Coupons - Dummy UI

[staskus]

Closes: #15403

Description

Show an error and CTA to proceed without Coupons.

Solution

• Updating orderState error set in PointOfSaleOrderController to be more versatile and allow expansion to specific error cases
• Added invalidCoupon error state
• Created CouponError to distinguish coupon errors both for self-hosted and Dotcom logins
• Created PointOfSaleOrderSyncCouponsErrorMessageView with dummy UI and ability to remove coupons before retrying order creation
• PointOfSaleOrderSyncCouponsErrorMessageView parses HTML error since sometimes coupons errors arrive with HTML tags

Steps to reproduce

Before testing, update addToCart method in PointOfSaleAggregateModel to add an invalid coupon with an item, for example:

    func addToCart(_ item: POSItem) {
        trackCustomerInteractionStarted()
        cart.add(POSItem.coupon(.init(id: UUID(), code: "10_invalid")))
        cart.add(item)
    }

Test with both Dotcom and Self-hosted login:

1. Log in with dotcom account
2. Open POS
3. Add an item and an invalid coupon
4. Check out
5. Confirm the error appears with an error message from the backend
6. Tap "Proceed without coupons"
7. Confirm the order is succesfully created

Testing information

• Test with Dotcom login
• Test with Self-hosted login

Screenshots

Simulator.Screen.Recording.-.iPad.Air.11-inch.M2.-.2025-03-25.at.15.46.47.mp4

---

• I have considered if this change warrants user-facing release notes and have added them to RELEASE-NOTES.txt if necessary.

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[wpmobilebot]

📲 You can test the changes from this Pull Request in WooCommerce iOS by scanning the QR code below to install the corresponding build.

	App Name	WooCommerce iOS
	Build Number	pr15420-6376ff7
	Version	22.0
	Bundle ID	com.automattic.alpha.woocommerce
	Commit	6376ff7
	App Center Build	WooCommerce - Prototype Builds #13421

Automatticians: You can use our internal self-serve MC tool to give yourself access to App Center if needed.

[iamgabrielma]

Works great! 🚢

Self-hosted

🔵 Tracked pos_order_creation_failed, properties: [error_description: The operation couldn’t be completed. (Networking.NetworkError error 2.), was_ecommerce_trial: false, plan: , site_url: https://indiemelon.mystagingwebsite.com, blog_id: -1, store_id: c5bd46cc-1804-4f7b-badb-bb98c449127f, is_wpcom_store: false, error_context: Sorry, there was an issue with the server. Please try again later. (Error code: 400). Response: {"code":"woocommerce_rest_invalid_coupon","message":"Coupon \"invalid_coupon\" does not exist!","data":{"status":400}}, use_gift_card: false]

Then:

🔵 Tracked pos_order_creation_success, properties: [store_id: c5bd46cc-1804-4f7b-badb-bb98c449127f, was_ecommerce_trial: false, is_wpcom_store: false, plan: , site_url: https://indiemelon.mystagingwebsite.com, blog_id: -1]

Dotcom:

🔵 Tracked pos_order_creation_failed, properties: [site_url: https://indiemelon.mystagingwebsite.com, use_gift_card: false, is_wpcom_store: false, error_description: The operation couldn’t be completed. (Networking.DotcomError error 0.), blog_id: 215063064, error_context: Dotcom Error: [woocommerce_rest_invalid_coupon] Coupon "invalid_coupon" does not exist!, plan: jetpack_security_daily, store_id: c5bd46cc-1804-4f7b-badb-bb98c449127f, was_ecommerce_trial: false]

then 

🔵 Tracked pos_order_creation_success, properties: [was_ecommerce_trial: false, blog_id: 215063064, is_wpcom_store: false, store_id: c5bd46cc-1804-4f7b-badb-bb98c449127f, plan: jetpack_security_daily, site_url: https://indiemelon.mystagingwebsite.com]

[iamgabrielma]

TIL we can also attempt to parse this to markdown via try AttributedString(markdown: message) (need to import Foundation). Maybe would be cleaner than using NSAttributedString, or we could keep both as a fallback if the initial decoding fails.

[staskus]

Thanks! I'll try 👍

[staskus]

Unfortunately, it doesn't parse through all the HTML tags. I tried different options but it didn't work.

[iamgabrielma]

Let's add a follow-up somewhere and a link here so we don't forget :D

[staskus]

👍 Okay, I will. All these PRs are with dummy UI so we'll need to do a second round to create a proper look,

[staskus]

• Created a task [Woo POS] Coupons: Checkout - Error Handling (Designer UI) #15424
• Added a comment 6376ff7