<?php

namespace App\Services\Mini;

use App\Models\MiniPayment;
use App\Models\QrCode;
use App\Services\Billing\BillingClient;
use App\Services\Billing\PaystackService;
use App\Services\Billing\SmsService;
use App\Services\Notifications\MiniNotificationService;
use App\Services\Pay\PayClient;
use App\Support\LadillLink;
use Illuminate\Support\Str;
use RuntimeException;

class MiniPaymentService
{
    public function __construct(
        private PayClient $pay,
        private PaystackService $paystack,
        private BillingClient $billing,
        private SmsService $sms,
        private MiniNotificationService $notifications,
        private AutoWithdrawService $autoWithdraw,
    ) {}

    /**
     * @param  array{amount: float, customer_phone?: string}  $data
     * @return array{payment: MiniPayment, checkout_url: string, provider: string}
     */
    public function initiate(QrCode $qrCode, array $data): array
    {
        if ($qrCode->type !== QrCode::TYPE_PAYMENT) {
            throw new RuntimeException('This QR is not a payment code.');
        }

        $amountGhs = round((float) ($data['amount'] ?? 0), 2);
        if ($amountGhs <= 0) {
            throw new RuntimeException('Enter an amount greater than zero.');
        }

        $customerPhone = trim((string) ($data['customer_phone'] ?? ''));

        $qrCode->loadMissing('user');
        $amountMinor = (int) round($amountGhs * 100);
        $reference = 'MINP-'.strtoupper(Str::random(16));
        $businessName = $qrCode->content()['business_name'] ?? $qrCode->label ?? 'Payment';

        $payment = MiniPayment::create([
            'qr_code_id' => $qrCode->id,
            'user_id' => $qrCode->user_id,
            'reference' => $reference,
            'amount_minor' => $amountMinor,
            'currency' => $qrCode->content()['currency'] ?? 'GHS',
            'payer_name' => null,
            'payer_email' => null,
            'payer_phone' => $customerPhone !== '' ? $customerPhone : null,
            'payer_note' => null,
            'status' => MiniPayment::STATUS_PENDING,
            'payment_reference' => null,
        ]);

        $checkout = [
            'merchant' => $qrCode->user->public_id,
            'fee_tier' => 'payments',
            'source_service' => 'mini',
            'source_ref' => (string) $qrCode->id,
            'callback_url' => LadillLink::path($qrCode->short_code, 'pay/callback'),
            'line_items' => [
                [
                    'name' => $businessName,
                    'unit_price_minor' => $amountMinor,
                    'quantity' => 1,
                ],
            ],
            'metadata' => [
                'mini_payment_id' => $payment->id,
                'mini_reference' => $reference,
                'qr_code_id' => $qrCode->id,
            ],
        ];

        if ($customerPhone !== '') {
            $checkout['customer_phone'] = $customerPhone;
        }

        $payOrder = $this->pay->createCheckout($checkout);

        $payment->update([
            'pay_order_id' => $payOrder['id'] ?? null,
            'payment_reference' => $payOrder['reference'],
            'platform_fee_minor' => $payOrder['platform_fee_minor'] ?? null,
            'merchant_amount_minor' => $payOrder['merchant_amount_minor'] ?? null,
        ]);

        $checkoutUrl = (string) ($payOrder['checkout_url'] ?? '');
        if ($checkoutUrl === '') {
            throw new RuntimeException('Could not start checkout. Please try again.');
        }

        return [
            'payment' => $payment->fresh(),
            'checkout_url' => $checkoutUrl,
            'provider' => (string) ($payOrder['provider'] ?? ''),
        ];
    }

    public function complete(string $paymentReference): MiniPayment
    {
        if (str_starts_with($paymentReference, 'LP-')) {
            return $this->completeLadillPay($paymentReference);
        }

        return $this->completeLegacy($paymentReference);
    }

    private function completeLadillPay(string $reference): MiniPayment
    {
        $payment = MiniPayment::where('payment_reference', $reference)
            ->where('status', MiniPayment::STATUS_PENDING)
            ->firstOrFail();

        $payOrder = $this->pay->verify($reference);

        $payment->update([
            'status' => MiniPayment::STATUS_PAID,
            'amount_minor' => (int) ($payOrder['amount_minor'] ?? $payment->amount_minor),
            'platform_fee_minor' => (int) ($payOrder['platform_fee_minor'] ?? 0),
            'merchant_amount_minor' => (int) ($payOrder['merchant_amount_minor'] ?? 0),
            'pay_order_id' => $payOrder['id'] ?? $payment->pay_order_id,
            'paid_at' => now(),
            'metadata' => array_merge((array) $payment->metadata, ['ladill_pay' => $payOrder]),
        ]);

        $payment = $payment->fresh(['qrCode', 'merchant']);
        $this->notifyPayer($payment);
        $this->notifications->paymentReceived($payment);
        $this->autoWithdraw->attemptForUser($payment->merchant);

        return $payment;
    }

    /** Legacy MIN-* references before Ladill Pay migration. */
    private function completeLegacy(string $paymentReference): MiniPayment
    {
        $payment = MiniPayment::where('payment_reference', $paymentReference)
            ->where('status', MiniPayment::STATUS_PENDING)
            ->firstOrFail();

        $data = $this->paystack->verifyTransaction($paymentReference);

        if (($data['status'] ?? '') !== 'success') {
            $payment->update(['status' => MiniPayment::STATUS_FAILED]);
            throw new RuntimeException('Payment was not successful.');
        }

        $paidMinor = (int) ($data['amount'] ?? $payment->amount_minor);
        $platformFeeMinor = (int) round($paidMinor * MiniPayment::PLATFORM_FEE_RATE);
        $merchantMinor = $paidMinor - $platformFeeMinor;

        $payment->update([
            'status' => MiniPayment::STATUS_PAID,
            'amount_minor' => $paidMinor,
            'platform_fee_minor' => $platformFeeMinor,
            'merchant_amount_minor' => $merchantMinor,
            'paid_at' => now(),
            'metadata' => array_merge((array) $payment->metadata, ['paystack' => $data, 'legacy' => true]),
        ]);

        $businessName = $payment->qrCode?->content()['business_name'] ?? $payment->qrCode?->label ?? 'Payment QR';
        $this->billing->credit(
            $payment->merchant->public_id,
            $merchantMinor,
            'mini',
            'pay',
            $paymentReference,
            $payment->id,
            sprintf('Payment via %s', $businessName),
        );

        $payment = $payment->fresh(['qrCode', 'merchant']);
        $this->notifyPayer($payment);
        $this->notifications->paymentReceived($payment);
        $this->autoWithdraw->attemptForUser($payment->merchant);

        return $payment;
    }

    private function notifyPayer(MiniPayment $payment): void
    {
        if (! $payment->payer_phone) {
            return;
        }

        $businessName = $payment->qrCode?->content()['business_name'] ?? $payment->qrCode?->label ?? 'Payment QR';

        $this->sms->send(
            $payment->payer_phone,
            sprintf(
                'Payment of %s %s to %s confirmed. Ref: %s',
                $payment->currency,
                number_format($payment->amount_minor / 100, 2),
                $businessName,
                $payment->reference
            )
        );
    }
}