// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
// See the LICENSE file in the project root for more information.
 
// Every unit test assembly should call GlobalBase.AssemblyInit() before running any tests.
// Test assembly should have following test also.
//
//    public void AssertHandlerTest()
//    {
//        GlobalBase.AssertHandlerTest();
//    }
 
using System;
using System.Runtime.InteropServices;
using Microsoft.ML.Runtime;
using Xunit;
 
namespace Microsoft.ML.Internal.Internallearn.Test
{
    internal static class GlobalBase
    {
        public static void AssemblyInit()
        {
            System.Diagnostics.Debug.WriteLine("*** Setting test assertion handler");
            var prev = Contracts.SetAssertHandler(AssertHandler);
            Contracts.Check(prev == null, "Expected to replace null assertion handler!");
 
            // Only do this for x86/x64. This will cause crashes in places IntelMKL is not supported.
            if (RuntimeInformation.ProcessArchitecture == Architecture.X64 || RuntimeInformation.ProcessArchitecture == Architecture.X86)
            {
                // Enable Conditional Numerical Reproducibility
                // https://software.intel.com/en-us/articles/introduction-to-the-conditional-numerical-reproducibility-cnr
                Environment.SetEnvironmentVariable("MKL_CBWR", "COMPATIBLE");
 
                // HACK: ensure MklImports is loaded very early in the tests so it doesn't deadlock while loading it later.
                // See https://github.com/dotnet/machinelearning/issues/1073
                Mkl.PptrfInternal(Mkl.Layout.RowMajor, Mkl.UpLo.Up, 0, Array.Empty<double>());
            }
        }
 
        private static class Mkl
        {
            public enum Layout
            {
                RowMajor = 101,
                ColMajor = 102
            }
 
            public enum UpLo : byte
            {
                Up = (byte)'U',
                Lo = (byte)'L'
            }
 
            [DllImport("MklImports", EntryPoint = "LAPACKE_dpptrf")]
            public static extern int PptrfInternal(Layout layout, UpLo uplo, int n, double[] ap);
        }
 
        public static void AssemblyCleanup()
        {
            System.Diagnostics.Debug.WriteLine("*** Restoring test assertion handler");
            var prev = Contracts.SetAssertHandler(null);
            Contracts.Check(prev == AssertHandler, "Expected to replace Global.AssertHandler!");
        }
 
#if DEBUG
        private static bool _ignoreOne;
#endif
        private static void AssertHandler(string msg, IExceptionContext ectx)
        {
#if DEBUG
            if (_ignoreOne)
            {
                _ignoreOne = false;
                Console.WriteLine("Assert handler invoked but ignored: {0}", msg);
            }
            else
#endif
            {
                Assert.Fail($"Assert failed: {msg}");
            }
        }
 
        public static void AssertHandlerTest()
        {
#if DEBUG
            Assert.False(_ignoreOne);
            _ignoreOne = true;
            try
            {
                Contracts.Assert(false, "This should invoke the handler");
                Assert.False(_ignoreOne);
            }
            finally
            {
                _ignoreOne = false;
            }
#endif
        }
    }
}