<?php

namespace App\Helpers;

use App\Models\Currency;
use Illuminate\Support\Facades\Cache;

class CurrencyHelper
{
    /**
     * Convert an amount from one currency to another using USD as pivot.
     */
    public static function convert(float $amount, string $fromCode, string $toCode): float
    {
        if ($fromCode === $toCode) {
            return $amount;
        }

        $fromRate = static::getExchangeRate($fromCode);
        $toRate = static::getExchangeRate($toCode);

        if ($fromRate <= 0 || $toRate <= 0) {
            return 0;
        }

        // Convert to USD first, then to target currency
        $usdAmount = $amount / $fromRate;

        return round($usdAmount * $toRate, 2);
    }

    /**
     * Get the exchange rate for a currency relative to USD.
     * Cached for 24 hours.
     */
    public static function getExchangeRate(string $currencyCode): float
    {
        return Cache::remember("exchange_rate_{$currencyCode}", now()->addHours(24), function () use ($currencyCode) {
            $currency = Currency::where('code', $currencyCode)
                ->where('is_active', true)
                ->first();

            return $currency?->exchange_rate_to_usd ?? 1;
        });
    }

    /**
     * Get the symbol for a currency.
     */
    public static function getCurrencySymbol(string $currencyCode): string
    {
        $currency = Currency::where('code', $currencyCode)->first();

        return $currency?->symbol ?? $currencyCode;
    }

    /**
     * Get the decimal places for a currency.
     */
    public static function getDecimalPlaces(string $currencyCode): int
    {
        $currency = Currency::where('code', $currencyCode)->first();

        return $currency?->decimal_places ?? 0;
    }

    /**
     * Format an amount with the currency symbol.
     */
    public static function formatWithSymbol(float $amount, string $currencyCode, string $locale = 'fa_IR'): string
    {
        $symbol = static::getCurrencySymbol($currencyCode);
        $decimals = static::getDecimalPlaces($currencyCode);
        $formatted = NumberHelper::formatNumber($amount, $decimals, $locale);

        return $formatted . ' ' . $symbol;
    }

    /**
     * Get the base currency for the current tenant.
     */
    public static function getBaseCurrency(): ?Currency
    {
        $tenantId = session('tenant_id');

        if (!$tenantId) {
            return null;
        }

        return Cache::remember("base_currency_{$tenantId}", now()->addHours(24), function () use ($tenantId) {
            $tenant = \App\Models\Tenant::find($tenantId);

            return $tenant?->baseCurrency;
        });
    }
}