<?php

namespace Modules\Cart\Http\Middleware;

use Closure;
use Exception;
use Modules\Cart\CartItem;
use Illuminate\Http\Request;
use Modules\Cart\Facades\Cart;
use Modules\FlashSale\Entities\FlashSale;
use Modules\Cart\Exceptions\CartItemsStockException;

class CheckCartItemsStock
{
    /**
     * Handle an incoming request.
     *
     * @param Request $request
     * @param Closure $next
     *
     * @return mixed
     */
    public function handle(Request $request, Closure $next): mixed
    {
        try {
            Cart::items()->each(function (CartItem $cartItem) {
                $cartItem->refreshStock();
                $this->checkStock($cartItem);
            });
        } catch (CartItemsStockException $e) {
            if (request()->wantsJson()) {
                return response()->json(
                    [
                        'message' => $e->getMessage(),
                    ],
                    400
                );
            }

            return redirect()->back()->with('error', $e->getMessage());
        } catch (Exception $e) {
            if (app()->hasDebugModeEnabled()) {
                $message = $e->getMessage();
            } else {
                $message = trans('core::something_went_wrong');
            }

            if (request()->ajax()) {
                return response()->json(
                    [
                        'message' => $message,
                    ],
                    400
                );
            }

            return redirect()->back()->with('error', $message);
        }

        return $next($request);
    }


    public function isInStock($cartItem)
    {
        return $cartItem->item->isInStock();
    }


    /**
     * @throws CartItemsStockException
     */
    private function checkStock(CartItem $cartItem): void
    {
        if (!$this->isInStock($cartItem)) {
            throw new CartItemsStockException(trans('cart::messages.one_or_more_product_is_out_of_stock'));
        }

        if (!$this->hasFlashSaleStock($cartItem)) {
            throw new CartItemsStockException(trans('cart::messages.one_or_more_product_doesn\'t_have_enough_stock'));
        }

        if (!$this->hasStock($cartItem)) {
            throw new CartItemsStockException(trans('cart::messages.one_or_more_product_doesn\'t_have_enough_stock'));
        }
    }


    private function hasFlashSaleStock(CartItem $cartItem): bool
    {
        if ($cartItem->variant || !FlashSale::contains($cartItem->product)) {
            return true;
        }

        $remainingQty = FlashSale::remainingQty($cartItem->product);
        $addedCartQty = Cart::addedQty($cartItem);

        return ($remainingQty - $addedCartQty) >= 0;
    }


    private function hasStock(CartItem $cartItem): bool
    {
        if (!$cartItem->item->manage_stock) {
            return true;
        }

        $addedCartQty = Cart::addedQty($cartItem);

        return ($cartItem->item->qty - $addedCartQty) >= 0;
    }
}