<?php

namespace App\Support;

use App\Models\Setting;

class VatSettings
{
    public const RATES_KEY = 'vat_settings';
    public const NUMBERING_KEY = 'vat_numbering';

    private static ?array $rates = null;

    public static function rateFor(?string $productType): float
    {
        if (!$productType) {
            return 0.0;
        }

        return (float) (self::rates()[$productType] ?? 0);
    }

    public static function numbering(): array
    {
        $saved = self::read(self::NUMBERING_KEY);

        return [
            'serial' => (string) ($saved['serial'] ?? '1C26TCP'),
            'next_number' => max(1, (int) ($saved['next_number'] ?? 1)),
            'padding' => min(12, max(1, (int) ($saved['padding'] ?? 8))),
            'auto_issue' => (bool) ($saved['auto_issue'] ?? false),
        ];
    }

    public static function saveNumbering(array $config): void
    {
        Setting::updateOrCreate(
            ['key' => self::NUMBERING_KEY],
            ['value' => json_encode($config, JSON_UNESCAPED_UNICODE)]
        );
    }

    public static function forget(): void
    {
        self::$rates = null;
    }

    private static function rates(): array
    {
        return self::$rates ??= collect(self::read(self::RATES_KEY))
            ->filter(fn ($row) => is_array($row) && isset($row['type']))
            ->mapWithKeys(fn ($row) => [$row['type'] => (float) ($row['vat_rate'] ?? 0)])
            ->all();
    }

    private static function read(string $key): array
    {
        $value = Setting::where('key', $key)->value('value');
        $decoded = is_string($value) ? json_decode($value, true) : null;

        return is_array($decoded) ? $decoded : [];
    }
}