// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.

using System;
using System.Globalization;
using System.Reflection;
using Xunit.Sdk;

namespace Microsoft.AspNetCore.Testing;

/// <summary>
/// Replaces the current culture and UI culture for the test.
/// </summary>
[AttributeUsage(AttributeTargets.Method)]
public class ReplaceCultureAttribute : BeforeAfterTestAttribute
{
    private const string _defaultCultureName = "en-GB";
    private const string _defaultUICultureName = "en-US";
    private CultureInfo _originalCulture;
    private CultureInfo _originalUICulture;

    /// <summary>
    /// Replaces the current culture and UI culture to en-GB and en-US respectively.
    /// </summary>
    public ReplaceCultureAttribute() :
        this(_defaultCultureName, _defaultUICultureName)
    {
    }

    /// <summary>
    /// Replaces the current culture and UI culture based on specified values.
    /// </summary>
    public ReplaceCultureAttribute(string currentCulture, string currentUICulture)
    {
        Culture = new CultureInfo(currentCulture);
        UICulture = new CultureInfo(currentUICulture);
    }

    /// <summary>
    /// The <see cref="CultureInfo.CurrentCulture"/> for the test. Defaults to en-GB.
    /// </summary>
    /// <remarks>
    /// en-GB is used here as the default because en-US is equivalent to the InvariantCulture. We
    /// want to be able to find bugs where we're accidentally relying on the Invariant instead of the
    /// user's culture.
    /// </remarks>
    public CultureInfo Culture { get; }

    /// <summary>
    /// The <see cref="CultureInfo.CurrentUICulture"/> for the test. Defaults to en-US.
    /// </summary>
    public CultureInfo UICulture { get; }

    public override void Before(MethodInfo methodUnderTest)
    {
        _originalCulture = CultureInfo.CurrentCulture;
        _originalUICulture = CultureInfo.CurrentUICulture;

        CultureInfo.CurrentCulture = Culture;
        CultureInfo.CurrentUICulture = UICulture;
    }

    public override void After(MethodInfo methodUnderTest)
    {
        CultureInfo.CurrentCulture = _originalCulture;
        CultureInfo.CurrentUICulture = _originalUICulture;
    }
}

