<?php
namespace Sodino\Services;

use Sodino\Repositories\UpsellRepository;

class UpsellService {
    private $upsellRepository;
    private $cache = null;

    public function __construct(UpsellRepository $upsellRepository) {
        $this->upsellRepository = $upsellRepository;
    }

    public function getActiveUpsells() {
        if ($this->cache === null) {
            $this->cache = $this->upsellRepository->getActive();
        }
        return $this->cache;
    }

    public function getMatchingUpsells($cart) {
        if (!$cart || $cart->is_empty()) {
            return [];
        }

        $matches = [];
        foreach ($this->getActiveUpsells() as $upsell) {
            if ($this->cartMatchesTrigger($upsell, $cart) && !$this->isProductAlreadyInCart($cart, $upsell->target_product_id)) {
                $matches[] = $upsell;
            }
        }

        usort($matches, function ($a, $b) {
            return $b->priority <=> $a->priority;
        });

        return $matches;
    }

    public function applyUpsellDiscount($product, $upsell) {
        if (!$product || !$upsell) {
            return 0;
        }

        $price = floatval($product->get_price());
        if ($upsell->discount_type === 'percentage') {
            return max(0, $price * (1 - floatval($upsell->discount_value) / 100));
        }

        if ($upsell->discount_type === 'fixed') {
            return max(0, $price - floatval($upsell->discount_value));
        }

        return $price;
    }

    public function getTriggerLabel($upsell) {
        switch ($upsell->trigger_type) {
            case 'product':
                return __('محصول خاص', 'sodino');
            case 'category':
                return __('دسته‌بندی', 'sodino');
            case 'cart_total':
                return __('مبلغ سبد خرید', 'sodino');
            default:
                return __('نامشخص', 'sodino');
        }
    }

    public function getDiscountLabel($upsell) {
        if ($upsell->discount_type === 'fixed') {
            return sprintf('%s تومان', number_format_i18n($upsell->discount_value));
        }

        if ($upsell->discount_type === 'percentage') {
            return sprintf('%s %%', esc_html($upsell->discount_value));
        }

        return __('بدون تخفیف', 'sodino');
    }

    private function cartMatchesTrigger($upsell, $cart) {
        if (!$upsell->isActive()) {
            return false;
        }

        $triggerType = $upsell->trigger_type;
        $triggerValue = $upsell->trigger_value;

        switch ($triggerType) {
            case 'product':
                return $this->cartContainsProduct($cart, intval($triggerValue));
            case 'category':
                return $this->cartContainsCategory($cart, intval($triggerValue));
            case 'cart_total':
                return floatval($cart->get_cart_contents_total()) >= floatval($triggerValue);
            default:
                return false;
        }
    }

    private function cartContainsProduct($cart, $productId) {
        if (!$productId) {
            return false;
        }

        foreach ($cart->get_cart() as $cartItem) {
            if ((int) $cartItem['product_id'] === $productId || (int) $cartItem['variation_id'] === $productId) {
                return true;
            }
        }

        return false;
    }

    private function cartContainsCategory($cart, $categoryId) {
        if (!$categoryId) {
            return false;
        }

        foreach ($cart->get_cart() as $cartItem) {
            $product = wc_get_product($cartItem['product_id']);
            if (!$product) {
                continue;
            }

            $terms = wp_get_post_terms($product->get_id(), 'product_cat', ['fields' => 'ids']);
            if (is_array($terms) && in_array($categoryId, $terms, true)) {
                return true;
            }
        }

        return false;
    }

    private function isProductAlreadyInCart($cart, $productId) {
        if (!$productId) {
            return false;
        }

        foreach ($cart->get_cart() as $cartItem) {
            if ((int) $cartItem['product_id'] === $productId || (int) $cartItem['variation_id'] === $productId) {
                return true;
            }
        }

        return false;
    }
}