#if XUNIT_NULLABLE
#nullable enable
#else
// In case this is source-imported with global nullable enabled but no XUNIT_NULLABLE
#pragma warning disable CS8604
#endif

using System;
using System.Diagnostics.CodeAnalysis;
using System.Globalization;

namespace Xunit.Sdk
{
	/// <summary>
	/// Exception thrown when Assert.Null fails.
	/// </summary>
#if XUNIT_VISIBILITY_INTERNAL
	internal
#else
	public
#endif
	partial class NullException : XunitException
	{
		NullException(string message) :
			base(message)
		{ }

		/// <summary>
		/// Creates a new instance of the <see cref="NullException"/> class to be thrown
		/// when the given nullable struct was unexpectedly not null.
		/// </summary>
		/// <param name="type">The inner type of the value</param>
		/// <param name="actual">The actual non-<c>null</c> value</param>
		public static Exception ForNonNullStruct<[DynamicallyAccessedMembers(
					DynamicallyAccessedMemberTypes.PublicFields
					| DynamicallyAccessedMemberTypes.NonPublicFields
					| DynamicallyAccessedMemberTypes.PublicProperties
					| DynamicallyAccessedMemberTypes.NonPublicProperties
					| DynamicallyAccessedMemberTypes.PublicMethods)] T>(
			Type type,
			T? actual)
				where T : struct =>
					new NullException(
						string.Format(
							CultureInfo.CurrentCulture,
							"Assert.Null() Failure: Value of type 'Nullable<{0}>' has a value{1}Expected: null{2}Actual:   {3}",
							ArgumentFormatter.FormatTypeName(Assert.GuardArgumentNotNull(nameof(type), type)),
							Environment.NewLine,
							Environment.NewLine,
							ArgumentFormatter.Format(actual)
						)
					);

		/// <summary>
		/// Creates a new instance of the <see cref="NullException"/> class to be thrown
		/// when the given value was unexpectedly not null.
		/// </summary>
		/// <param name="actual">The actual non-<c>null</c> value</param>
		[UnconditionalSuppressMessage("ReflectionAnalysis", "IL2019:Mismatched constraints",
						Justification = "Assert.GuardArgumentNotNull returns the same type passed in, so the annotations on the T type parameter will work")]
		public static NullException ForNonNullValue<[DynamicallyAccessedMembers(
					DynamicallyAccessedMemberTypes.PublicFields
					| DynamicallyAccessedMemberTypes.NonPublicFields
					| DynamicallyAccessedMemberTypes.PublicProperties
					| DynamicallyAccessedMemberTypes.NonPublicProperties
					| DynamicallyAccessedMemberTypes.PublicMethods)] T>(T actual) =>
			new NullException(
				string.Format(
					CultureInfo.CurrentCulture,
					"Assert.Null() Failure: Value is not null{0}Expected: null{1}Actual:   {2}",
					Environment.NewLine,
					Environment.NewLine,
					ArgumentFormatter.Format(Assert.GuardArgumentNotNull(nameof(actual), actual))
				)
			);
	}
}