<?php

namespace App\Http\Controllers\Checkout;

use App\Http\Controllers\Controller;
use Illuminate\Http\Request;
use Illuminate\View\View;
use Lunar\Models\ProductVariant;
use Modules\Core\Cart\Exceptions\InvalidCouponException;
use Modules\Core\Cart\Services\CartService;

/**
 * Thin storefront cart endpoints for the checkout module. Every action mutates
 * the session cart via boboko-core's CartService and returns the same
 * server-rendered `cart-body` partial — the drawer's Stimulus controller swaps
 * that fragment in place (no JSON, no client-side templating). $cart / $lines
 * for the partial come from the view composer in CheckoutModuleServiceProvider.
 */
class CartController extends Controller
{
    public function __construct(
        private readonly CartService $cart,
    ) {}

    public function add(string $locale, Request $request): View
    {
        $data = $request->validate([
            'purchasable_id' => ['required', 'integer'],
            'quantity' => ['nullable', 'integer', 'min:1'],
        ]);

        $variant = ProductVariant::findOrFail($data['purchasable_id']);

        $this->cart->addLine($variant, $data['quantity'] ?? 1);

        return view('checkout::partials.cart-body');
    }

    public function updateLine(string $locale, Request $request, int $line): View
    {
        $quantity = (int) $request->validate([
            'quantity' => ['required', 'integer', 'min:0'],
        ])['quantity'];

        $quantity === 0
            ? $this->cart->removeLine($line)
            : $this->cart->updateLine($line, $quantity);

        return view('checkout::partials.cart-body');
    }

    public function remove(string $locale, int $line): View
    {
        $this->cart->removeLine($line);

        return view('checkout::partials.cart-body');
    }

    /**
     * A bad code is a normal, expected outcome here (typo, expired code), not
     * an error state for the request — it re-renders the same cart-body
     * partial with $couponError set, rather than a 4xx/redirect, so the fetch
     * + swap in bbk-cart-controller stays the one code path for every cart
     * mutation.
     */
    public function applyCoupon(string $locale, Request $request): View
    {
        $code = $request->validate([
            'code' => ['required', 'string'],
        ])['code'];

        $couponError = false;

        try {
            $this->cart->applyCoupon($code);
        } catch (InvalidCouponException) {
            $couponError = true;
        }

        return view('checkout::partials.cart-body', ['couponError' => $couponError]);
    }

    public function removeCoupon(string $locale): View
    {
        $this->cart->removeCoupon();

        return view('checkout::partials.cart-body');
    }
}