chatroom/app/Http/Requests/CreateVipPaymentOrderRequest.php

<?php

/**
 * 文件功能：创建 VIP 支付订单请求
 * 负责校验前台用户发起 VIP 购买时提交的会员等级参数
 */

namespace App\Http\Requests;

use Illuminate\Foundation\Http\FormRequest;

class CreateVipPaymentOrderRequest extends FormRequest
{
    /**
     * 判断当前用户是否允许发起购买
     */
    public function authorize(): bool
    {
        return $this->user() !== null;
    }

    /**
     * 获取字段校验规则
     *
     * @return array<string, array<int, string>>
     */
    public function rules(): array
    {
        return [
            'vip_level_id' => ['required', 'integer', 'exists:vip_levels,id'],
        ];
    }

    /**
     * 配置验证器实例。
     *
     * @param  \Illuminate\Validation\Validator  $validator
     * @return void
     */
    public function withValidator($validator): void
    {
        $validator->after(function ($validator) {
            $user = $this->user();
            if (! $user || ! $user->isVip()) {
                return;
            }

            $vipLevelId = (int) $this->vip_level_id;
            $targetLevel = \App\Models\VipLevel::find($vipLevelId);

            if (! $targetLevel) {
                return;
            }

            $currentLevelId = (int) $user->vip_level_id;

            // 逻辑：允许续费当前等级，或购买更高等级。禁止降级。
            if ($vipLevelId !== $currentLevelId && ! $targetLevel->isHigherThan($currentLevelId)) {
                $validator->errors()->add('vip_level_id', '当前仅支持续费同级会员或补差价升级到更高等级，暂不支持降级购买。');
            }
        });
    }

    /**
     * 获取中文错误提示
     *
     * @return array<string, string>
     */
    public function messages(): array
    {
        return [
            'vip_level_id.required' => '请选择要购买的 VIP 等级',
            'vip_level_id.exists' => '所选 VIP 等级不存在或已被删除',
        ];
    }
}