<?php

namespace App\Services\Merchant;

use App\Models\QrBooking;
use App\Models\QrCode;
use App\Models\QrSaleOrder;
use Carbon\Carbon;
use App\Services\Billing\BillingClient;
use App\Services\Billing\PaystackService;
use App\Services\Billing\SmsService;
use App\Services\Pay\PayClient;
use App\Services\Payments\MerchantGatewayService;
use App\Support\LadillLink;
use App\Support\Qr\QrTypeCatalog;
use RuntimeException;

class MerchantSaleService
{
    public function __construct(
        private PayClient $pay,
        private PaystackService $paystack,
        private BillingClient $billing,
        private SmsService $sms,
        private KitchenPusher $kitchen,
        private MerchantGatewayService $gateway,
    ) {}

    /**
     * @param  array{customer_name: string, customer_email: string, customer_phone: ?string, shipping_fee?: float, items: list<array{name: string, price: float, qty: int}>}  $data
     * @return array{order: QrSaleOrder, checkout_url: string, callback_url: string}
     */
    public function initiateOrder(QrCode $qrCode, array $data): array
    {
        if (! in_array($qrCode->type, \App\Support\Qr\QrTypeCatalog::storefrontTypes(), true)) {
            throw new RuntimeException('This QR is not a merchant storefront.');
        }

        $items = $this->normalizeItems($data['items'] ?? []);
        if (empty($items)) {
            throw new RuntimeException('Your cart is empty.');
        }

        $shippingFee = round(max(0, (float) ($data['shipping_fee'] ?? 0)), 2);
        if ($shippingFee > 0) {
            $items[] = ['name' => 'Shipping', 'price_ghs' => $shippingFee, 'qty' => 1];
        }

        $totalGhs = collect($items)->sum(fn ($i) => $i['price_ghs'] * $i['qty']);
        if ($totalGhs <= 0) {
            throw new RuntimeException('Order total must be greater than zero to process payment.');
        }

        $qrCode->loadMissing('user');
        $customerEmail = trim((string) ($data['customer_email'] ?? ''));
        $callbackUrl = LadillLink::path($qrCode->short_code, 'order/callback');

        $usesOwnerGateway = $this->gateway->shouldUseOwnerGateway($qrCode->user);
        $payOrder = null;
        if ($usesOwnerGateway) {
            try {
                $payOrder = $this->gateway->initialize(
                    $qrCode->user, (int) round($totalGhs * 100),
                    (string) ($qrCode->content()['currency'] ?? 'GHS'),
                    (string) config('pay.mini_checkout_email', 'pay@ladill.com'), $callbackUrl,
                    'MGP-'.strtoupper(\Illuminate\Support\Str::random(16)),
                    ['qr_code_id' => $qrCode->id, 'short_code' => $qrCode->short_code, 'type' => 'order'],
                );
            } catch (\Throwable) {
                $usesOwnerGateway = false;
            }
        }
        if (! $usesOwnerGateway) {
            $payOrder = $this->pay->createCheckout([
            'merchant' => $qrCode->user->public_id,
            'fee_tier' => 'sales',
            'source_service' => 'merchant',
            'source_ref' => (string) $qrCode->id,
            'callback_url' => $callbackUrl,
            'customer_name' => trim((string) ($data['customer_name'] ?? '')),
            'customer_email' => $customerEmail,
            'customer_phone' => trim((string) ($data['customer_phone'] ?? '')) ?: null,
            'line_items' => collect($items)->map(fn (array $i) => [
                'name' => $i['name'],
                'unit_price_minor' => (int) round($i['price_ghs'] * 100),
                'quantity' => $i['qty'],
            ])->all(),
            'metadata' => [
                'qr_code_id' => $qrCode->id,
                'short_code' => $qrCode->short_code,
            ],
            ]);
        }

        $order = QrSaleOrder::create([
            'pay_order_id' => $usesOwnerGateway ? null : ($payOrder['id'] ?? null),
            'qr_code_id' => $qrCode->id,
            'user_id' => $qrCode->user_id,
            'customer_name' => trim((string) ($data['customer_name'] ?? '')),
            'customer_email' => $customerEmail ?: null,
            'customer_phone' => trim((string) ($data['customer_phone'] ?? '')) ?: null,
            'items' => $items,
            'amount_ghs' => $usesOwnerGateway ? $totalGhs : round(($payOrder['amount_minor'] ?? 0) / 100, 2),
            'status' => QrSaleOrder::STATUS_PENDING,
            'payment_reference' => $payOrder['reference'],
        ]);

        return [
            'order' => $order,
            'checkout_url' => (string) ($payOrder['checkout_url'] ?? ''),
            'access_code' => isset($payOrder['access_code']) ? (string) $payOrder['access_code'] : null,
            'public_key' => isset($payOrder['public_key']) ? (string) $payOrder['public_key'] : null,
            'callback_url' => $callbackUrl,
        ];
    }

    /**
     * @param  array{customer_name: string, customer_email: string, customer_phone: ?string, service_index: int, starts_at: string}  $data
     * @return array{booking: QrBooking, checkout_url: ?string, callback_url: ?string}
     */
    public function initiateBooking(QrCode $qrCode, array $data): array
    {
        if (! $qrCode->isBookingType()) {
            throw new RuntimeException('This QR is not a booking page.');
        }

        $content = $qrCode->content();
        $services = $content['services'] ?? [];
        $serviceIndex = (int) ($data['service_index'] ?? -1);
        $service = $services[$serviceIndex] ?? null;
        if (! is_array($service)) {
            throw new RuntimeException('Select a valid service.');
        }

        $serviceName = trim((string) ($service['name'] ?? ''));
        $duration = max(15, (int) ($service['duration_minutes'] ?? 30));
        $priceGhs = round(max(0, (float) ($service['price_ghs'] ?? 0)), 2);
        $startsAt = Carbon::parse((string) ($data['starts_at'] ?? ''));
        $endsAt = $startsAt->copy()->addMinutes($duration);

        if ($startsAt->isPast()) {
            throw new RuntimeException('That time slot has passed. Pick another.');
        }

        $qrCode->loadMissing('user');
        $customerEmail = trim((string) ($data['customer_email'] ?? ''));
        $callbackUrl = LadillLink::path($qrCode->short_code, 'booking/callback');

        $booking = QrBooking::create([
            'qr_code_id' => $qrCode->id,
            'user_id' => $qrCode->user_id,
            'customer_name' => trim((string) ($data['customer_name'] ?? '')),
            'customer_email' => $customerEmail ?: null,
            'customer_phone' => trim((string) ($data['customer_phone'] ?? '')) ?: null,
            'service_name' => $serviceName,
            'duration_minutes' => $duration,
            'starts_at' => $startsAt,
            'ends_at' => $endsAt,
            'amount_ghs' => $priceGhs,
            'status' => QrBooking::STATUS_PENDING,
            'metadata' => ['service_index' => $serviceIndex],
        ]);

        if ($priceGhs <= 0 || ! ($content['accepts_payment'] ?? true)) {
            $booking->update([
                'status' => QrBooking::STATUS_CONFIRMED,
                'fulfillment_status' => QrBooking::FULFILLMENT_CONFIRMED,
                'paid_at' => now(),
            ]);
            $this->notifyBookingConfirmed($booking->fresh(['qrCode']));

            return ['booking' => $booking, 'checkout_url' => null, 'callback_url' => null];
        }

        $lineLabel = sprintf('%s — %s', $serviceName, $startsAt->format('D j M, g:i A'));
        $usesOwnerGateway = $this->gateway->shouldUseOwnerGateway($qrCode->user);
        $payOrder = null;
        if ($usesOwnerGateway) {
            try {
                $payOrder = $this->gateway->initialize(
                    $qrCode->user, (int) round($priceGhs * 100),
                    (string) ($content['currency'] ?? 'GHS'),
                    (string) config('pay.mini_checkout_email', 'pay@ladill.com'), $callbackUrl,
                    'MGP-'.strtoupper(\Illuminate\Support\Str::random(16)),
                    ['qr_code_id' => $qrCode->id, 'qr_booking_id' => $booking->id, 'type' => 'booking'],
                );
            } catch (\Throwable) {
                $usesOwnerGateway = false;
            }
        }
        if (! $usesOwnerGateway) {
            $payOrder = $this->pay->createCheckout([
            'merchant' => $qrCode->user->public_id,
            'fee_tier' => 'sales',
            'source_service' => 'merchant',
            'source_ref' => (string) $qrCode->id,
            'callback_url' => $callbackUrl,
            'customer_name' => $booking->customer_name,
            'customer_email' => $customerEmail,
            'customer_phone' => $booking->customer_phone,
            'line_items' => [
                ['name' => $lineLabel, 'unit_price_minor' => (int) round($priceGhs * 100), 'quantity' => 1],
            ],
            'metadata' => [
                'qr_code_id' => $qrCode->id,
                'qr_booking_id' => $booking->id,
                'type' => 'booking',
            ],
            ]);
        }

        $booking->update([
            'pay_order_id' => $usesOwnerGateway ? null : ($payOrder['id'] ?? null),
            'payment_reference' => $payOrder['reference'],
        ]);

        return [
            'booking' => $booking,
            'checkout_url' => (string) ($payOrder['checkout_url'] ?? ''),
            'access_code' => isset($payOrder['access_code']) ? (string) $payOrder['access_code'] : null,
            'public_key' => isset($payOrder['public_key']) ? (string) $payOrder['public_key'] : null,
            'callback_url' => $callbackUrl,
        ];
    }

    public function completeBooking(string $reference): QrBooking
    {
        if (str_starts_with($reference, 'LP-')) {
            return $this->completeLadillPayBooking($reference);
        }
        if (str_starts_with($reference, 'MGP-')) {
            return $this->completeOwnerGatewayBooking($reference);
        }

        return $this->completeLegacyBooking($reference);
    }

    public function completeOrder(string $reference): QrSaleOrder
    {
        if (str_starts_with($reference, 'LP-')) {
            return $this->completeLadillPay($reference);
        }
        if (str_starts_with($reference, 'MGP-')) {
            return $this->completeOwnerGateway($reference);
        }

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

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

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

        $order->update([
            'status' => QrSaleOrder::STATUS_PAID,
            'paid_at' => now(),
            'platform_fee_ghs' => round(($payOrder['platform_fee_minor'] ?? 0) / 100, 2),
            'merchant_amount_ghs' => round(($payOrder['merchant_amount_minor'] ?? 0) / 100, 2),
            'pay_order_id' => $payOrder['id'] ?? $order->pay_order_id,
            'metadata' => array_merge((array) $order->metadata, ['ladill_pay' => $payOrder]),
        ]);

        $this->notifyOrderPlaced($order->fresh(['qrCode', 'merchant']));
        $this->kitchen->push($order->fresh(['qrCode', 'merchant']));

        return $order;
    }

    private function completeLegacy(string $reference): QrSaleOrder
    {
        $order = QrSaleOrder::where('payment_reference', $reference)
            ->where('status', QrSaleOrder::STATUS_PENDING)
            ->firstOrFail();

        $data = $this->paystack->verifyTransaction($reference);
        if (($data['status'] ?? '') !== 'success') {
            $order->update(['status' => QrSaleOrder::STATUS_FAILED]);
            throw new RuntimeException('Payment was not successful.');
        }

        $paidAmount = round(($data['amount'] ?? 0) / 100, 2);
        $platformFee = round($paidAmount * QrSaleOrder::PLATFORM_FEE_RATE, 2);
        $merchantAmount = round($paidAmount - $platformFee, 2);

        $order->update([
            'status' => QrSaleOrder::STATUS_PAID,
            'paid_at' => now(),
            'platform_fee_ghs' => $platformFee,
            'merchant_amount_ghs' => $merchantAmount,
            'metadata' => array_merge((array) $order->metadata, ['paystack' => $data, 'legacy' => true]),
        ]);

        $storeName = $order->qrCode?->label ?? 'Storefront';
        $this->billing->credit(
            $order->merchant->public_id,
            (int) round($merchantAmount * 100),
            'merchant',
            'pay',
            $reference,
            $order->id,
            sprintf('Sale from %s — %s', $storeName, $order->customer_name ?: 'Customer'),
        );

        $this->notifyOrderPlaced($order->fresh(['qrCode', 'merchant']));
        $this->kitchen->push($order->fresh(['qrCode', 'merchant']));

        return $order;
    }

    private function completeOwnerGateway(string $reference): QrSaleOrder
    {
        $order = QrSaleOrder::where('payment_reference', $reference)
            ->where('status', QrSaleOrder::STATUS_PENDING)
            ->with('merchant')
            ->firstOrFail();
        $result = $this->gateway->verify($order->merchant, $reference);
        if (! $result['paid']) {
            $order->update(['status' => QrSaleOrder::STATUS_FAILED]);
            throw new RuntimeException('Payment was not successful.');
        }
        $paidMinor = (int) ($result['amount_minor'] ?: round($order->amount_ghs * 100));
        $order->update([
            'status' => QrSaleOrder::STATUS_PAID,
            'paid_at' => now(),
            'amount_ghs' => round($paidMinor / 100, 2),
            'platform_fee_ghs' => 0,
            'merchant_amount_ghs' => round($paidMinor / 100, 2),
            'metadata' => array_merge((array) $order->metadata, ['merchant_gateway' => $result]),
        ]);
        $this->notifyOrderPlaced($order->fresh(['qrCode', 'merchant']));
        $this->kitchen->push($order->fresh(['qrCode', 'merchant']));

        return $order;
    }

    private function completeLadillPayBooking(string $reference): QrBooking
    {
        $booking = QrBooking::where('payment_reference', $reference)
            ->where('status', QrBooking::STATUS_PENDING)
            ->firstOrFail();

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

        $booking->update([
            'status' => QrBooking::STATUS_CONFIRMED,
            'fulfillment_status' => QrBooking::FULFILLMENT_CONFIRMED,
            'paid_at' => now(),
            'platform_fee_ghs' => round(($payOrder['platform_fee_minor'] ?? 0) / 100, 2),
            'merchant_amount_ghs' => round(($payOrder['merchant_amount_minor'] ?? 0) / 100, 2),
            'pay_order_id' => $payOrder['id'] ?? $booking->pay_order_id,
            'metadata' => array_merge((array) $booking->metadata, ['ladill_pay' => $payOrder]),
        ]);

        $this->notifyBookingConfirmed($booking->fresh(['qrCode']));

        return $booking;
    }

    private function completeLegacyBooking(string $reference): QrBooking
    {
        $booking = QrBooking::where('payment_reference', $reference)
            ->where('status', QrBooking::STATUS_PENDING)
            ->firstOrFail();

        $data = $this->paystack->verifyTransaction($reference);
        if (($data['status'] ?? '') !== 'success') {
            $booking->update(['status' => QrBooking::STATUS_FAILED]);
            throw new RuntimeException('Payment was not successful.');
        }

        $paidAmount = round(($data['amount'] ?? 0) / 100, 2);
        $platformFee = round($paidAmount * QrSaleOrder::PLATFORM_FEE_RATE, 2);
        $merchantAmount = round($paidAmount - $platformFee, 2);

        $booking->update([
            'status' => QrBooking::STATUS_CONFIRMED,
            'fulfillment_status' => QrBooking::FULFILLMENT_CONFIRMED,
            'paid_at' => now(),
            'platform_fee_ghs' => $platformFee,
            'merchant_amount_ghs' => $merchantAmount,
            'metadata' => array_merge((array) $booking->metadata, ['paystack' => $data, 'legacy' => true]),
        ]);

        $this->billing->credit(
            $booking->merchant->public_id,
            (int) round($merchantAmount * 100),
            'merchant',
            'pay',
            $reference,
            $booking->id,
            sprintf('Booking — %s', $booking->service_name),
        );

        $this->notifyBookingConfirmed($booking->fresh(['qrCode']));

        return $booking;
    }

    private function completeOwnerGatewayBooking(string $reference): QrBooking
    {
        $booking = QrBooking::where('payment_reference', $reference)
            ->where('status', QrBooking::STATUS_PENDING)
            ->with('merchant')
            ->firstOrFail();
        $result = $this->gateway->verify($booking->merchant, $reference);
        if (! $result['paid']) {
            $booking->update(['status' => QrBooking::STATUS_FAILED]);
            throw new RuntimeException('Payment was not successful.');
        }
        $paidMinor = (int) ($result['amount_minor'] ?: round($booking->amount_ghs * 100));
        $booking->update([
            'status' => QrBooking::STATUS_CONFIRMED,
            'fulfillment_status' => QrBooking::FULFILLMENT_CONFIRMED,
            'paid_at' => now(),
            'amount_ghs' => round($paidMinor / 100, 2),
            'platform_fee_ghs' => 0,
            'merchant_amount_ghs' => round($paidMinor / 100, 2),
            'metadata' => array_merge((array) $booking->metadata, ['merchant_gateway' => $result]),
        ]);
        $this->notifyBookingConfirmed($booking->fresh(['qrCode']));

        return $booking;
    }

    private function notifyBookingConfirmed(QrBooking $booking): void
    {
        if (! $booking->customer_phone) {
            return;
        }

        $business = $booking->qrCode?->content()['booking_title'] ?? $booking->qrCode?->label ?? 'Business';
        $this->sms->send(
            $booking->customer_phone,
            sprintf(
                'Hi %s, your booking for %s at %s is confirmed for %s. Ref: %s',
                explode(' ', $booking->customer_name ?? 'there')[0],
                $booking->service_name,
                $business,
                $booking->starts_at->format('D j M, g:i A'),
                $booking->payment_reference ?? ('BK-'.$booking->id)
            )
        );
    }

    public function notifyBookingStatusUpdated(QrBooking $booking): void
    {
        if (! $booking->customer_phone) {
            return;
        }

        $business = $booking->qrCode?->content()['booking_title'] ?? $booking->qrCode?->label ?? 'Business';
        $this->sms->send(
            $booking->customer_phone,
            sprintf(
                'Hi %s, your booking at %s (%s) is now: %s.',
                explode(' ', $booking->customer_name ?? 'there')[0],
                $business,
                $booking->starts_at->format('D j M, g:i A'),
                $booking->fulfillmentLabel()
            )
        );
    }

    public function notifyStatusUpdated(QrSaleOrder $order): void
    {
        if (! $order->customer_phone) {
            return;
        }

        $storeName = $order->qrCode?->label ?? config('app.name');
        $this->sms->send(
            $order->customer_phone,
            sprintf(
                'Hi %s, your order #%d at %s is now: %s.',
                explode(' ', $order->customer_name ?? 'there')[0],
                $order->id,
                $storeName,
                $order->fulfillmentLabel()
            )
        );
    }

    private function notifyOrderPlaced(QrSaleOrder $order): void
    {
        if (! $order->customer_phone) {
            return;
        }

        $storeName = $order->qrCode?->label ?? config('app.name');
        $this->sms->send(
            $order->customer_phone,
            sprintf(
                'Hi %s, your order #%d at %s has been received! Total: GHS %s. Ref: %s',
                explode(' ', $order->customer_name ?? 'there')[0],
                $order->id,
                $storeName,
                number_format((float) $order->amount_ghs, 2),
                $order->payment_reference
            )
        );
    }

    /** @return list<array{name: string, price_ghs: float, qty: int}> */
    private function normalizeItems(array $items): array
    {
        $normalized = [];
        foreach ($items as $item) {
            $name = trim((string) ($item['name'] ?? ''));
            $price = max(0, (float) ($item['price'] ?? 0));
            $qty = max(1, (int) ($item['qty'] ?? 1));

            if ($name === '' || $price <= 0) {
                continue;
            }

            $normalized[] = [
                'name' => $name,
                'price_ghs' => $price,
                'qty' => $qty,
            ];
        }

        return $normalized;
    }
}