<?php

namespace App\Services;

use Carbon\CarbonInterface;
use Illuminate\Support\Facades\DB;
use Illuminate\Validation\Rule;
use InvalidArgumentException;

class RewardGrantSettingsService
{
    public const TYPES = ['rebate', 'backflow'];
    public const TIMEZONE = 'Asia/Shanghai';

    public static function get(string $type): array
    {
        self::checkType($type);
        $row = DB::table('reward_grant_settings')->where('type', $type)->first();
        return [
            'type' => $type,
            'auto_enabled' => (int) ($row->auto_enabled ?? 0),
            'grant_time' => $row->grant_time ?? '03:00',
            'timezone' => self::TIMEZONE,
        ];
    }

    public static function save(string $type, array $params): array
    {
        self::checkType($type);
        // Validate here so HTTP and other callers share the same write rules.
        $params = validator($params, [
            'auto_enabled' => ['required', 'boolean'],
            'grant_time' => [Rule::requiredIf(fn () => in_array($params['auto_enabled'] ?? null, [1, '1', true], true)),
                'nullable', 'date_format:H:i'],
        ])->validate();

        return DB::transaction(function () use ($type, $params) {
            $values = ['type' => $type, 'auto_enabled' => (bool) $params['auto_enabled'],
                'created_at' => now(), 'updated_at' => now()];
            $updates = ['auto_enabled', 'updated_at'];
            if (!empty($params['grant_time'])) {
                $values['grant_time'] = $params['grant_time'];
                $updates[] = 'grant_time';
            }
            DB::table('reward_grant_settings')->upsert([$values], ['type'], $updates);
            return self::get($type);
        });
    }

    public static function dueAt(?object $setting, CarbonInterface $now): ?CarbonInterface
    {
        if (!$setting || (int) $setting->auto_enabled !== 1
            || !preg_match('/^(?:[01]\d|2[0-3]):[0-5]\d$/D', (string) $setting->grant_time)) {
            return null;
        }
        $local = $now->copy()->setTimezone(self::TIMEZONE);
        [$hour, $minute] = array_map('intval', explode(':', $setting->grant_time));
        $scheduled = $local->copy()->setTime($hour, $minute, 0);
        return $local->greaterThanOrEqualTo($scheduled) ? $scheduled : null;
    }

    private static function checkType(string $type): void
    {
        if (!in_array($type, self::TYPES, true)) throw new InvalidArgumentException('奖励类型错误');
    }
}