feat(reviews): add review service and Stripe payment gateway

src/Services/ReviewService.php

@@ -0,0 +1,65 @@
+<?php
+
+namespace Bazaar\Services;
+
+use Bazaar\Core\Database;
+use Bazaar\Repositories\ReviewRepository;
+
+final class ReviewService
+{
+    public const eligible = 'eligible';
+    public const notPurchased = 'notPurchased';
+    public const alreadyReviewed = 'alreadyReviewed';
+
+    public function __construct(
+        private readonly Database $db,
+        private readonly ReviewRepository $reviews
+    ) {
+    }
+
+    public function hasPurchased(int $userId, int $productId): bool
+    {
+        return (int) $this->db->scalar(
+            "SELECT COUNT(*)
+             FROM orders o
+             JOIN orderItems oi ON oi.orderId = o.id
+             WHERE o.userId = ? AND oi.productId = ? AND o.status IN ('paid', 'fulfilled')",
+            [$userId, $productId]
+        ) > 0;
+    }
+
+    public function eligibility(int $userId, int $productId): string
+    {
+        if (!$this->hasPurchased($userId, $productId)) {
+            return self::notPurchased;
+        }
+        if ($this->reviews->existsForUser($productId, $userId)) {
+            return self::alreadyReviewed;
+        }
+        return self::eligible;
+    }
+
+    public function canReview(int $userId, int $productId): bool
+    {
+        return $this->eligibility($userId, $productId) === self::eligible;
+    }
+
+    public function submit(int $userId, int $productId, int $rating, string $title, string $body): int
+    {
+        if (!$this->canReview($userId, $productId)) {
+            throw new \RuntimeException('This account is not eligible to review this product.');
+        }
+        $rating = max(1, min(5, $rating));
+        return $this->reviews->create($productId, $userId, $rating, trim($title), trim($body));
+    }
+
+    public function approve(int $reviewId): void
+    {
+        $this->reviews->setStatus($reviewId, 'approved');
+    }
+
+    public function reject(int $reviewId): void
+    {
+        $this->reviews->setStatus($reviewId, 'rejected');
+    }
+}

src/Services/StripeGateway.php

@@ -0,0 +1,65 @@
+<?php
+
+namespace Bazaar\Services;
+
+use Stripe\StripeClient;
+use Stripe\Webhook;
+
+final class StripeGateway
+{
+    private StripeClient $client;
+
+    public function __construct(
+        private readonly string $secretKey,
+        private readonly string $webhookSecret,
+        private readonly string $currency
+    ) {
+        $this->client = new StripeClient($this->secretKey);
+    }
+
+    public function createCheckoutSession(int $orderId, array $lines, string $successUrl, string $cancelUrl): array
+    {
+        $lineItems = [];
+        foreach ($lines as $line) {
+            $lineItems[] = [
+                'quantity' => $line['quantity'],
+                'price_data' => [
+                    'currency' => $this->currency,
+                    'unit_amount' => (int) $line['product']['priceCents'],
+                    'product_data' => [
+                        'name' => $line['product']['name'],
+                    ],
+                ],
+            ];
+        }
+
+        $session = $this->client->checkout->sessions->create([
+            'mode' => 'payment',
+            'line_items' => $lineItems,
+            'success_url' => $successUrl,
+            'cancel_url' => $cancelUrl,
+            'client_reference_id' => (string) $orderId,
+            'metadata' => ['orderId' => (string) $orderId],
+        ]);
+
+        return ['id' => $session->id, 'url' => $session->url];
+    }
+
+    public function retrieveSession(string $sessionId): array
+    {
+        $session = $this->client->checkout->sessions->retrieve($sessionId);
+        return [
+            'paymentStatus' => $session->payment_status,
+            'orderId' => isset($session->metadata->orderId) ? (int) $session->metadata->orderId : null,
+        ];
+    }
+
+    public function parseWebhook(string $payload, string $signature): array
+    {
+        $event = Webhook::constructEvent($payload, $signature, $this->webhookSecret);
+        return [
+            'type' => $event->type,
+            'session' => $event->data->object,
+        ];
+    }
+}