using FsCheck;
using FsCheck.Xunit;
using HuangyanParking.Domain.Utils;

namespace HuangyanParking.Tests;

/// <summary>
/// 核销验证的属性测试
/// </summary>
public class VerifyPropertyTests
{
    // 自定义生成器：生成有效的优惠券状态
    private static readonly string[] ValidStatuses = ["unused", "used", "expired"];

    /// <summary>
    /// Feature: huangyan-parking-points, Property 10: 券码验证正确性
    /// 券码存在且未使用且属于当前门店则通过，否则失败并返回错误原因
    /// Validates: Requirements 11.3, 11.5, 12.2
    /// </summary>
    [Property(MaxTest = 100)]
    public bool CouponVerify_ShouldValidateCorrectly(
        bool couponExists,
        byte statusIndex,
        PositiveInt couponStoreIdWrapper,
        PositiveInt verifyStoreIdWrapper)
    {
        // 从有效状态中选取
        var status = couponExists ? ValidStatuses[statusIndex % ValidStatuses.Length] : null;
        var couponStoreId = couponStoreIdWrapper.Get;
        var verifyStoreId = verifyStoreIdWrapper.Get;

        var result = CouponVerifier.Validate(couponExists, status, couponStoreId, verifyStoreId);

        if (!couponExists)
        {
            // 券码不存在 → 失败
            return !result.IsValid && result.ErrorMessage == "券码无效";
        }

        if (status == "used")
        {
            return !result.IsValid && result.ErrorMessage == "优惠券已使用";
        }

        if (status == "expired")
        {
            return !result.IsValid && result.ErrorMessage == "优惠券已过期";
        }

        if (status == "unused" && couponStoreId != verifyStoreId)
        {
            return !result.IsValid && result.ErrorMessage == "该优惠券不适用于本门店";
        }

        if (status == "unused" && couponStoreId == verifyStoreId)
        {
            // 全部条件满足 → 通过
            return result.IsValid;
        }

        // 其他异常状态 → 失败
        return !result.IsValid;
    }

    /// <summary>
    /// Feature: huangyan-parking-points, Property 11: 核销操作正确性
    /// 核销后券状态变为已使用，用户端查询反映已使用状态
    /// Validates: Requirements 11.4, 11.6
    /// </summary>
    [Property(MaxTest = 100)]
    public bool CouponVerify_AfterVerification_StatusShouldBeUsed()
    {
        // 对于未使用的优惠券执行核销
        var newStatus = CouponVerifier.ApplyVerification("unused");

        // 核销后状态应为已使用
        return newStatus == "used";
    }
}