using YZWater.Core.Services;

namespace YZWater.Core.Tests.Services;

/// <summary>
/// AuthService 密码哈希相关测试（纯函数，无需数据库）
/// </summary>
public class AuthPasswordTests
{
    [Fact]
    public void HashPassword_ReturnsPbkdf2Format()
    {
        var hash = AuthService.HashPassword("test123");

        Assert.StartsWith("pbkdf2$", hash);
        var parts = hash.Split('$');
        Assert.Equal(4, parts.Length);
        Assert.Equal("pbkdf2", parts[0]);
        Assert.Equal("100000", parts[1]);
    }

    [Fact]
    public void HashPassword_ProducesUniqueHashesEachCall()
    {
        var hash1 = AuthService.HashPassword("same_password");
        var hash2 = AuthService.HashPassword("same_password");

        // 由于盐值随机，每次哈希结果应不同
        Assert.NotEqual(hash1, hash2);
    }

    [Fact]
    public void VerifyPassword_CorrectPassword_ReturnsTrue()
    {
        var password = "my_secure_password";
        var hash = AuthService.HashPassword(password);

        Assert.True(AuthService.VerifyPassword(password, hash));
    }

    [Fact]
    public void VerifyPassword_WrongPassword_ReturnsFalse()
    {
        var hash = AuthService.HashPassword("correct_password");

        Assert.False(AuthService.VerifyPassword("wrong_password", hash));
    }

    [Fact]
    public void VerifyPassword_NullHash_ReturnsFalse()
    {
        Assert.False(AuthService.VerifyPassword("any_password", null));
    }

    [Fact]
    public void VerifyPassword_EmptyHash_ReturnsFalse()
    {
        Assert.False(AuthService.VerifyPassword("any_password", ""));
        Assert.False(AuthService.VerifyPassword("any_password", "   "));
    }

    [Fact]
    public void VerifyPassword_InvalidFormat_ReturnsFalse()
    {
        Assert.False(AuthService.VerifyPassword("password", "not-a-valid-hash"));
    }

    [Fact]
    public void VerifyPassword_EmptyPassword_Works()
    {
        var hash = AuthService.HashPassword("");

        Assert.True(AuthService.VerifyPassword("", hash));
        Assert.False(AuthService.VerifyPassword("not_empty", hash));
    }

    [Fact]
    public void VerifyPassword_ChinesePassword_Works()
    {
        var password = "中文密码测试";
        var hash = AuthService.HashPassword(password);

        Assert.True(AuthService.VerifyPassword(password, hash));
        Assert.False(AuthService.VerifyPassword("其他密码", hash));
    }
}