<?php

namespace App\Services;

use App\Models\SystemSetting;
use App\Models\ExchangeRateHistory;

class ExchangeRateService
{
    /**
     * دریافت نرخ فعلی
     */
    public function getCurrentRate(string $from = 'AED', string $to = 'IRR'): float
    {
        $key = strtolower("{$from}_to_{$to}");
        $setting = SystemSetting::where('key', $key)->first();
        
        if (!$setting) {
            return config('ifnex.financial_defaults.aed_to_irr', 455000);
        }
        
        return (float) $setting->value;
    }

    /**
     * تنظیم نرخ جدید (توسط کاربر)
     */
    public function setRate(
        string $from,
        string $to,
        float $newRate,
        ?int $userId = null,
        ?string $notes = null
    ): ExchangeRateHistory {
        $key = strtolower("{$from}_to_{$to}");
        $oldRate = $this->getCurrentRate($from, $to);

        SystemSetting::updateOrCreate(
            ['key' => $key],
            [
                'value' => (string) $newRate,
                'type' => 'number',
                'description' => "{$from} to {$to} exchange rate",
            ]
        );

        return $this->recordChange(
            from: $from,
            to: $to,
            oldRate: $oldRate,
            newRate: $newRate,
            source: 'manual',
            userId: $userId,
            notes: $notes
        );
    }

    /**
     * دریافت آخرین تغییرات
     */
    public function getLatestChanges(int $limit = 10)
    {
        return ExchangeRateHistory::with('changedBy')
            ->orderBy('created_at', 'desc')
            ->limit($limit)
            ->get();
    }

    /**
     * دریافت اطلاعات آخرین نرخ برای Widget
     * ⚠️ بدون استفاده از scope - کوئری مستقیم
     */
    public function getLatestRateInfo(string $from = 'AED', string $to = 'IRR'): array
    {
        // ✅ کوئری مستقیم بدون scope
        $latest = ExchangeRateHistory::where('currency_from', $from)
            ->where('currency_to', $to)
            ->orderBy('created_at', 'desc')
            ->with('changedBy')
            ->first();
        
        $currentRate = $this->getCurrentRate($from, $to);

        return [
            'current_rate' => $currentRate,
            'last_change' => $latest,
            'last_updated' => $latest?->created_at,
            'changed_by' => $latest?->changedBy?->name,
            'source' => $latest?->change_source,
            'change_percent' => $latest?->change_percent,
        ];
    }

    /**
     * دریافت آخرین N نرخ برای Chart
     */
    public function getRateChart(string $from = 'AED', string $to = 'IRR', int $limit = 7): array
    {
        return ExchangeRateHistory::where('currency_from', $from)
            ->where('currency_to', $to)
            ->orderBy('created_at', 'asc')
            ->limit($limit)
            ->pluck('new_rate')
            ->toArray();
    }

    /**
     * ثبت تغییر نرخ
     */
    private function recordChange(
        string $from,
        string $to,
        float $oldRate,
        float $newRate,
        string $source = 'manual',
        ?int $userId = null,
        ?string $apiSource = null,
        ?string $notes = null
    ): ExchangeRateHistory {
        $changePercent = null;
        if ($oldRate > 0) {
            $changePercent = round((($newRate - $oldRate) / $oldRate) * 100, 4);
        }

        return ExchangeRateHistory::create([
            'currency_from' => $from,
            'currency_to' => $to,
            'old_rate' => $oldRate,
            'new_rate' => $newRate,
            'change_percent' => $changePercent,
            'change_source' => $source,
            'changed_by' => $userId,
            'api_source' => $apiSource,
            'notes' => $notes,
        ]);
    }
}