<?php

namespace Modules\Core\Shipping\Concerns;

use Lunar\DataTypes\ShippingOption;
use Lunar\Facades\Pricing;
use Lunar\Shipping\Models\ShippingMethod;
use Lunar\Shipping\Models\ShippingRate;

/**
 * Shared by any carrier driver that also supports Lunar's own price-break
 * pricing (charge_by = cart_total | weight) as a fallback to, or standalone
 * alternative for, live API pricing. Mirrors the vendor ShipBy driver's
 * charge_by handling exactly, so behavior is consistent with the rest of
 * Lunar's shipping system rather than inventing a separate mechanism.
 */
trait ResolvesFixedPricing
{
    private function resolveFixedPrice(ShippingRate $shippingRate, ShippingMethod $shippingMethod, $cart): ?ShippingOption
    {
        $chargeBy = $shippingMethod->data['charge_by'] ?? 'cart_total';

        $tier = $chargeBy === 'weight'
            ? $cart->lines->load('purchasable')->sum(fn ($line) => ($line->purchasable->weight_value ?? 0) * $line->quantity)
            : $cart->lines->sum('subTotal.value');

        $pricing = Pricing::for($shippingRate)->qty($tier)->get();

        if (! $pricing->matched) {
            return null;
        }

        return new ShippingOption(
            name: $shippingMethod->name ?: $this->name(),
            description: $shippingMethod->description ?: $this->description(),
            identifier: $shippingRate->getIdentifier(),
            price: $pricing->matched->price,
            taxClass: $shippingRate->getTaxClass(),
            taxReference: $shippingRate->getTaxReference(),
        );
    }
}