<?php
namespace Sodino\Services;

use Sodino\Repositories\EventRepository;

class TrackingService {
    private $eventRepository;
    private $loggedEvents = [];

    public function __construct(EventRepository $eventRepository) {
        $this->eventRepository = $eventRepository;
    }

    public function trackProductView($product_id) {
        if (!$product_id) {
            return;
        }

        $session_key = 'sodino_viewed_' . intval($product_id);
        if ($this->hasLogged($session_key)) {
            return;
        }

        $this->logEvent('product_view', [
            'product_id' => $product_id,
        ]);
        $this->markLogged($session_key);
    }

    public function trackAddToCart($product_id, $variation_id = null, $quantity = 1) {
        if (!$product_id) {
            return;
        }

        $this->logEvent('add_to_cart', [
            'product_id' => $product_id,
            'variation_id' => $variation_id,
            'value' => floatval($quantity),
        ]);
    }

    public function trackCheckoutStart() {
        $this->logEvent('checkout_start', []);
    }

    public function trackPurchase($order_id) {
        if (!$order_id) {
            return;
        }

        $order = wc_get_order($order_id);
        if (!$order) {
            return;
        }

        $total = floatval($order->get_total());
        $discount = 0;
        if (method_exists($order, 'get_total_discount')) {
            $discount = floatval($order->get_total_discount());
        } else {
            foreach ($order->get_items() as $item) {
                $discount += floatval($item->get_subtotal()) - floatval($item->get_total());
            }
        }

        $this->logEvent('purchase', [
            'value' => $total,
            'discount_value' => max(0, $discount),
        ]);
    }

    public function recordDiscountApplied($product, $original_price, $discounted_price, $rule_id = null) {
        if (!$product || $original_price <= 0 || $discounted_price >= $original_price) {
            return;
        }

        $product_id = $product->get_id();
        $variation_id = $product->is_type('variation') ? $product_id : 0;
        $discount_value = round($original_price - $discounted_price, 2);

        $key = 'discount_applied_' . $product_id . '_' . $rule_id . '_' . $discount_value;
        if ($this->hasLogged($key)) {
            return;
        }

        $this->logEvent('discount_applied', [
            'product_id' => $product_id,
            'variation_id' => $variation_id,
            'rule_id' => $rule_id,
            'value' => $discounted_price,
            'discount_value' => $discount_value,
        ]);
        $this->markLogged($key);
    }

    public function getRuleUsageCount($rule_id) {
        return $this->eventRepository->getRuleUsageCount($rule_id);
    }

    private function logEvent($type, array $data = []) {
        $event = [
            'event_type' => $type,
            'product_id' => isset($data['product_id']) ? intval($data['product_id']) : null,
            'variation_id' => isset($data['variation_id']) ? intval($data['variation_id']) : null,
            'user_id' => get_current_user_id() ?: null,
            'session_id' => $this->getSessionId(),
            'rule_id' => isset($data['rule_id']) ? intval($data['rule_id']) : null,
            'value' => isset($data['value']) ? floatval($data['value']) : 0,
            'discount_value' => isset($data['discount_value']) ? floatval($data['discount_value']) : 0,
            'metadata' => isset($data['metadata']) ? wp_json_encode($data['metadata']) : null,
            'created_at' => current_time('mysql'),
        ];

        $this->eventRepository->insert($event);
    }

    private function getSessionId() {
        if (function_exists('WC') && WC()->session) {
            $session_id = WC()->session->get('sodino_session_id');
            if (!$session_id) {
                $session_id = uniqid('sodino_', true);
                WC()->session->set('sodino_session_id', $session_id);
            }
            return $session_id;
        }

        return 'guest_' . md5($_SERVER['REMOTE_ADDR'] . '|' . $_SERVER['HTTP_USER_AGENT']);
    }

    private function hasLogged($key) {
        return isset($this->loggedEvents[$key]);
    }

    private function markLogged($key) {
        $this->loggedEvents[$key] = true;
    }
}