<?php

namespace App\Services\Payment;

use App\Models\Payment;
use Illuminate\Http\Client\ConnectionException;
use Illuminate\Support\Facades\Http;
use Illuminate\Support\Facades\Log;

/**
 * PayMongo driver scaffold. Wires the SDK calls but is gated on
 * PAYMONGO_SECRET_KEY being set. When the key is missing we treat the
 * driver as misconfigured and return failure — the caller can then
 * fall back to ManualPaymentDriver.
 */
class PayMongoDriver implements PaymentDriver
{
    public function __construct(
        private readonly string $secretKey,
        private readonly string $webhookSecret,
        private readonly string $endpoint = 'https://api.paymongo.com/v1',
        private readonly string $successUrl = 'https://verde.local/payment/success',
        private readonly string $cancelUrl = 'https://verde.local/payment/cancel',
    ) {}

    public function initiate(Payment $payment): InitiateResult
    {
        if (empty($this->secretKey)) {
            return InitiateResult::failure('paymongo_not_configured');
        }

        try {
            $response = Http::withBasicAuth($this->secretKey, '')
                ->timeout(15)
                ->post($this->endpoint.'/checkout_sessions', [
                    'data' => [
                        'attributes' => [
                            'line_items' => [[
                                'name' => $payment->purpose,
                                'amount' => $payment->amount_centavos,
                                'currency' => $payment->currency,
                                'quantity' => 1,
                            ]],
                            'payment_method_types' => ['gcash', 'paymaya', 'card'],
                            'success_url' => $this->successUrl.'?p='.$payment->uuid,
                            'cancel_url' => $this->cancelUrl.'?p='.$payment->uuid,
                            'metadata' => ['payment_uuid' => $payment->uuid],
                        ],
                    ],
                ]);
        } catch (ConnectionException $e) {
            Log::warning('PayMongo connection failed', ['error' => $e->getMessage()]);

            return InitiateResult::failure('connection_failed');
        }

        if (! $response->successful()) {
            Log::warning('PayMongo error', ['status' => $response->status(), 'body' => $response->body()]);

            return InitiateResult::failure('provider_error_'.$response->status());
        }

        $data = $response->json('data') ?? [];
        $sessionId = $data['id'] ?? null;
        $checkoutUrl = $data['attributes']['checkout_url'] ?? null;

        $payment->forceFill([
            'provider' => Payment::PROVIDER_PAYMONGO,
            'provider_payment_id' => $sessionId,
            'provider_data' => $data,
            'status' => Payment::STATUS_PROCESSING,
        ])->save();

        return InitiateResult::success($checkoutUrl, $sessionId);
    }

    public function verifyWebhook(string $rawBody, string $signature): bool
    {
        if (empty($this->webhookSecret)) {
            return false;
        }

        // PayMongo webhook header format: t=timestamp,te=signature,li=...
        $parts = [];
        foreach (explode(',', $signature) as $kv) {
            [$k, $v] = array_pad(explode('=', $kv, 2), 2, '');
            $parts[$k] = $v;
        }

        $timestamp = $parts['t'] ?? '';
        $signed = $parts['te'] ?? '';
        $expected = hash_hmac('sha256', "{$timestamp}.{$rawBody}", $this->webhookSecret);

        return hash_equals($expected, $signed);
    }

    public function applyWebhook(array $payload): ?Payment
    {
        $eventType = $payload['data']['attributes']['type'] ?? null;
        $paymentUuid = $payload['data']['attributes']['data']['attributes']['metadata']['payment_uuid'] ?? null;
        if (! $paymentUuid) return null;

        $payment = Payment::where('uuid', $paymentUuid)->first();
        if (! $payment) return null;

        if (in_array($eventType, ['checkout_session.payment.paid', 'payment.paid'], true)) {
            $payment->forceFill([
                'status' => Payment::STATUS_PAID,
                'paid_at' => now(),
                'provider_data' => $payload,
            ])->save();
        } elseif (in_array($eventType, ['payment.failed'], true)) {
            $payment->forceFill([
                'status' => Payment::STATUS_FAILED,
                'provider_data' => $payload,
            ])->save();
        }

        return $payment->fresh();
    }
}