package checkout

import (
	"fmt"

	messages "git.k6n.net/go-cart-actor/proto/checkout"
)

// mutation_remove_delivery.go
//
// Registers the RemoveDelivery mutation.
//
// Behavior:
//   - Removes the delivery entry whose Id == payload.Id.
//   - If not found, returns an error.
//   - Items previously associated with that delivery simply become "without delivery";
//     subsequent delivery mutations can reassign them.

func HandleRemoveDelivery(g *CheckoutGrain, m *messages.RemoveDelivery) error {
	if m == nil {
		return fmt.Errorf("RemoveDelivery: nil payload")
	}
	targetID := uint32(m.Id)
	index := -1
	for i, d := range g.Deliveries {
		if d.Id == targetID {
			index = i
			break
		}
	}
	if index == -1 {
		return fmt.Errorf("RemoveDelivery: delivery id %d not found", m.Id)
	}

	// Remove delivery (order not preserved beyond necessity)
	g.Deliveries = append(g.Deliveries[:index], g.Deliveries[index+1:]...)
	return nil
}