<?php

namespace App\Services;

use App\Models\Country;
use App\Models\CountryZone;
use App\Models\DiscountCode;
use App\Models\RateEntry;
use App\Models\SystemSetting;
use App\Enums\ShipmentDirection;

/**
 * PriceCalculatorService
 * ----------------------
 * موتور قیمت‌گذاری ۴-رُبعی — همه نرخ‌ها به ریال (IRR).
 *
 * ─── معماری ارزی ───
 * ارز مبنا = ریال ایران. نرخ‌ها در دیتابیس به ریال ذخیره می‌شوند
 * (تبدیل در زمان ایمپورت توسط RateImportService انجام می‌شود).
 * بنابراین موتور محاسبه نیازی به تبدیل ارز ندارد.
 */
class PriceCalculatorService
{
    public function __construct(
        protected ExchangeRateService $exchangeRate,
    ) {}

    public function calculate(array $input): array
    {
        // ۱. نرمال‌سازی direction
        $directionRaw = strtolower((string) ($input['direction'] ?? ''));
        $direction = match ($directionRaw) {
            'outbound'        => 'export',
            'inbound'         => 'import',
            'export', 'import' => $directionRaw,
            default           => null,
        };
        if ($direction === null) {
            throw new \InvalidArgumentException(
                "Invalid direction: " . ($input['direction'] ?? '(empty)') . " — expected 'export'|'import'|'Outbound'|'Inbound'"
            );
        }

        // ۲. نرمال‌سازی type → service_type
        $typeRaw = strtoupper(trim((string) ($input['type'] ?? '')));
        $serviceType = match ($typeRaw) {
            'DOC_NORMAL', 'DOC_ECONOMY', 'DOCUMENT', 'DOC', 'DOCNORMAL', 'DOCECONOMY' => 'document',
            'PARCEL', 'NON DOC', 'NON-DOC', 'NONDOC', 'NON_DOCUMENT'                  => 'parcel',
            default => null,
        };
        if ($serviceType === null) {
            throw new \InvalidArgumentException(
                "Invalid type: " . ($input['type'] ?? '(empty)') . " — expected DOC_NORMAL|DOC_ECONOMY|PARCEL"
            );
        }

        // ۳. حل کشور با ISO → نام
        $countryIso = strtoupper(trim((string) ($input['country_iso'] ?? '')));
        if (strlen($countryIso) !== 2) {
            throw new \InvalidArgumentException(
                "Invalid country_iso: must be exactly 2 letters, got: " . ($input['country_iso'] ?? '(empty)')
            );
        }
        $country = Country::where('iso_code', $countryIso)->first();
        if (! $country) {
            throw new \RuntimeException("Country not found for ISO: {$countryIso}");
        }
        $countryName = $country->name;

        // ۴. اوزان
        $weight           = (float) ($input['weight'] ?? 0);
        $volumetricWeight = (float) ($input['volumetric_weight'] ?? 0);
        $chargeableWeight = max($weight, $volumetricWeight);

        // ۵. جستجوی زون
        $zone = CountryZone::lookupZone($countryName, $serviceType);
        if ($zone === null) {
            throw new \RuntimeException(
                "No zone mapping for country '{$countryName}' service type '{$serviceType}'. "
                . "Please import the Zone sheet via admin → Rate Management."
            );
        }

        // ۶. جستجوی نرخ — مستقیماً به ریال (IRR)
        $rateEntry = RateEntry::lookup($direction, $serviceType, $chargeableWeight, $zone, 'IRR');
        if (! $rateEntry) {
            throw new \RuntimeException(
                "No rate found for {$direction}×{$serviceType} weight={$chargeableWeight}kg zone={$zone}. "
                . "Please import rates via admin → Rate Management."
            );
        }

        // ۷. قیمت پایه — مستقیماً به ریال
        $basePriceIrr = (float) $rateEntry->rate;

        // ۸. هزینه‌های جانبی — همه به ریال
        $extras = [
            'extra_service'     => (float) ($input['extra_service']     ?? 0),
            'packing_cost'      => (float) ($input['packing_cost']      ?? 0),
            'domestic_pickup'   => (float) ($input['domestic_pickup']   ?? 0),
            'domestic_delivery' => (float) ($input['domestic_delivery'] ?? 0),
            'warehousing_cost'  => (float) ($input['warehousing_cost']  ?? 0),
        ];
        $extrasTotalIrr = array_sum($extras);

        // ۹. اعمال ضریب سود + هزینه‌های جانبی
        $profitMargin = (float) SystemSetting::get(
            'profit_margin',
            config('ifnex.financial_defaults.profit_margin', 1.25)
        );
        if ($profitMargin <= 0) {
            $profitMargin = 1.0;
        }

        $netRial = ($basePriceIrr * $profitMargin) + $extrasTotalIrr;

        // ۱۰. مالیات بر ارزش افزوده
        $vatRate = (float) SystemSetting::get(
            'vat_rate',
            config('ifnex.financial_defaults.vat_rate', 0.09)
        );
        $vatAmount = $netRial * $vatRate;

        // ۱۱. تخفیف
        $discountApplied = false;
        $discountAmount  = 0.0;
        $discountCode    = trim((string) ($input['discount_code'] ?? ''));

        if ($discountCode !== '') {
            $discount = DiscountCode::where('code', $discountCode)
                ->where('is_active', true)
                ->where(function ($q) {
                    $q->whereNull('expires_at')
                      ->orWhere('expires_at', '>', now());
                })
                ->first();

            if ($discount) {
                $subtotal = $netRial + $vatAmount;
                $minOrder = (float) ($discount->min_order_amount ?? 0);
                if ($minOrder > 0 && $subtotal < $minOrder) {
                    // زیر سقف
                } else {
                    $discountApplied = true;
                    if ($discount->type === 'percentage') {
                        $discountAmount = $subtotal * ((float) $discount->value / 100);
                    } else {
                        $discountAmount = min((float) $discount->value, $subtotal);
                    }
                }
            }
        }

        // ۱۲. مبلغ نهایی (گردش به ۱۰۰۰ ریال)
        $totalFee = $netRial + $vatAmount - $discountAmount;
        $totalFee = (int) round($totalFee / 1000) * 1000;

        return [
            'base_price'        => round($basePriceIrr, 2),
            'net_rial'           => (int) round($netRial),
            'packing_cost'       => round($extras['packing_cost'], 2),
            'vat_amount'         => (int) round($vatAmount),
            'discount_applied'   => $discountApplied,
            'discount_amount'    => (int) round($discountAmount),
            'total_fee'          => $totalFee,
            'extra_service'      => round($extras['extra_service'], 2),
            'domestic_pickup'    => round($extras['domestic_pickup'], 2),
            'domestic_delivery'  => round($extras['domestic_delivery'], 2),
            'warehousing_cost'   => round($extras['warehousing_cost'], 2),
            'weight'             => round($weight, 3),
            'volumetric_weight'  => round($volumetricWeight, 3),
            'chargeable_weight'  => round($chargeableWeight, 3),
            'zone'               => $zone,
            'service_type'       => $serviceType,
            'direction'           => $direction,
            'country'            => $countryName,
            'country_iso'        => $countryIso,
            'rate_entry_id'      => $rateEntry->id,
            'profit_margin'      => $profitMargin,
            'currency'           => 'IRR',
        ];
    }

    public function calculateForShipment($shipment): array
    {
        $direction = $shipment->direction?->value ?? (string) $shipment->direction;
        $type      = $shipment->type?->value      ?? (string) $shipment->type;

        $country = ($direction === 'export')
            ? $shipment->toCountry
            : $shipment->fromCountry;

        return $this->calculate([
            'direction'         => $direction,
            'type'              => $type,
            'country_iso'       => $country?->iso_code,
            'weight'            => (float) ($shipment->weight ?? 0),
            'volumetric_weight' => (float) ($shipment->volumetric_weight ?? 0),
            'extra_service'     => (float) ($shipment->extra_service ?? 0),
            'packing_cost'      => (float) ($shipment->packing_cost ?? 0),
            'domestic_pickup'   => (float) ($shipment->domestic_pickup ?? 0),
            'domestic_delivery' => (float) ($shipment->domestic_delivery ?? 0),
            'warehousing_cost'  => (float) ($shipment->warehousing_cost ?? 0),
        ]);
    }
}