<?php

namespace App\Services;

use App\DTOs\AffiliateResult;
use App\Interfaces\AffiliateConverterInterface;

class LinkConverterService
{
    protected AffiliateConverterInterface $converter;
    protected HistoryService $historyService;
    protected SettingService $settingService;

    public function __construct(
        AffiliateConverterInterface $converter,
        HistoryService $historyService,
        SettingService $settingService
    ) {
        $this->converter = $converter;
        $this->historyService = $historyService;
        $this->settingService = $settingService;
    }

    public function process(
        string $url,
        ?string $zaloThreadId = null,
        ?string $zaloChatName = null,
        string $sourceType = 'web',
        ?string $customerName = null,
        ?string $customerPhone = null
    ): AffiliateResult
    {
        // 1. Generate unique code beforehand for tracking
        $code = null;
        do {
            $code = \Illuminate\Support\Str::random(10);
        } while (\App\Models\ConversionHistory::whereRaw('BINARY code = ?', [$code])->exists());

        // 2. Fetch real Shopee product information
        $productInfo = $this->fetchShopeeProductInfo($url);
        $productTitle = $productInfo['name'] ?? null;
        $productImage = $productInfo['image'] ?? null;
        $productPrice = $productInfo['price'] ?? 0.00;
        
        // Determine estimated commission rate and amount
        $commissionData = $this->calculateEstimatedCommission($productTitle, $productPrice, $productInfo['is_mall'] ?? false);
        $estimatedCommission = $commissionData['amount'];

        $maxRetries = $this->settingService->get('retry_count', 3);
        $attempts = 0;
        $result = null;

        while ($attempts < $maxRetries) {
            $attempts++;
            // 3. Convert with the pre-generated code for sub_id mapping
            $result = $this->converter->convert($url, $code);

            if ($result->isSuccess) {
                break;
            }
        }

        // Save history regardless of success or failure
        if ($result) {
            $history = $this->historyService->logConversion(
                $result,
                $code,
                $zaloThreadId,
                $zaloChatName,
                $customerName,
                $customerPhone,
                $productTitle,
                $productImage,
                $productPrice,
                $estimatedCommission
            );
            
            // Override converter type if triggered from external source (like Zalo)
            if ($history && $sourceType !== 'web') {
                $history->update([
                    'converter_type' => $sourceType
                ]);
            }

            if ($result->isSuccess && $history->code) {
                $domain = $this->settingService->get('short_link_domain');
                if ($domain) {
                    $domain = rtrim($domain, '/');
                    $result->affiliateUrl = $domain . '/aff/s/' . $history->code;
                } else {
                    $result->affiliateUrl = route('short_link.redirect', ['code' => $history->code]);
                }
            }
        }

        return $result;
    }

    /**
     * Fetch product details (title, image, price) from Shopee internal API.
     */
    public function fetchShopeeProductInfo(string $url): ?array
    {
        if (!preg_match('/i\.(\d+)\.(\d+)/', $url, $matches)) {
            return null;
        }

        $shopId = $matches[1];
        $itemId = $matches[2];
        $apiUrl = "https://shopee.vn/api/v4/item/get?itemid={$itemId}&shopid={$shopId}";

        try {
            $response = \Illuminate\Support\Facades\Http::timeout(5)
                ->withHeaders([
                    'User-Agent' => 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/120.0.0.0 Safari/537.36',
                    'Accept' => 'application/json',
                    'Referer' => 'https://shopee.vn/',
                ])
                ->get($apiUrl);

            if ($response->successful()) {
                $data = $response->json();
                $item = $data['data'] ?? null;
                if ($item) {
                    $price = isset($item['price']) ? $item['price'] / 100000 : 0;
                    $image = isset($item['image']) ? "https://down-vn.img.susercontent.com/file/" . $item['image'] : null;
                    return [
                        'name' => $item['name'] ?? null,
                        'price' => $price,
                        'image' => $image,
                        'is_mall' => !empty($item['is_official_shop']),
                        'description' => $item['description'] ?? null
                    ];
                }
            }
        } catch (\Exception $e) {
            \Illuminate\Support\Facades\Log::warning("Shopee internal API lookup failed: " . $e->getMessage());
        }

        return null;
    }

    /**
     * Calculate estimated commission based on category keywords and Mall status.
     */
    protected function calculateEstimatedCommission(?string $title, float $price, bool $isMall): array
    {
        if (!$title || $price <= 0) {
            return ['rate' => 0, 'amount' => 0.00];
        }

        $titleLower = mb_strtolower($title);
        
        // Define category keywords
        $fashionKeywords = ['áo', 'quần', 'váy', 'đầm', 'giày', 'túi', 'kính', 'son', 'kem', 'phấn', 'nước hoa', 'tắm', 'gội', 'phụ kiện', 'trang sức', 'skincare', 'scrub'];
        $electronicsKeywords = ['điện thoại', 'laptop', 'tivi', 'loa', 'tai nghe', 'máy ảnh', 'sạc', 'cáp', 'chuột', 'bàn phím', 'camera', 'micro', 'usb', 'thẻ nhớ', 'router', 'wifi', 'pin'];

        $isFashion = false;
        foreach ($fashionKeywords as $keyword) {
            if (str_contains($titleLower, $keyword)) {
                $isFashion = true;
                break;
            }
        }

        $isElectronics = false;
        if (!$isFashion) {
            foreach ($electronicsKeywords as $keyword) {
                if (str_contains($titleLower, $keyword)) {
                    $isElectronics = true;
                    break;
                }
            }
        }

        // Apply rates
        if ($isFashion) {
            $rate = $isMall ? 7.4 : 3.5;
        } elseif ($isElectronics) {
            $rate = $isMall ? 1.5 : 0.8;
        } else {
            // General categories
            $rate = $isMall ? 5.0 : 2.5;
        }

        // Allow admin settings override if configured
        $adminOverrideRate = $this->settingService->get('commission_rate_override');
        if ($adminOverrideRate !== null && $adminOverrideRate !== '') {
            $rate = (float)$adminOverrideRate;
        }

        return [
            'rate' => $rate,
            'amount' => round($price * ($rate / 100), 2)
        ];
    }
}