using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Reflection;
using System.Runtime.InteropServices;
using Burst.Compiler.IL.Tests.Helpers;
using NUnit.Framework;
using NUnit.Framework.Interfaces;
using NUnit.Framework.Internal;
using NUnit.Framework.Internal.Builders;
using NUnit.Framework.Internal.Commands;
using Unity.Burst;
using Unity.Collections;
using Unity.Mathematics;
using UnityBenchShared;
#if !BURST_TESTS_ONLY
using ExecutionContext = NUnit.Framework.Internal.ITestExecutionContext;
#else
using ExecutionContext = NUnit.Framework.Internal.TestExecutionContext;
#endif

namespace Burst.Compiler.IL.Tests
{
    /// <summary>
    /// When used as a type in TestCompiler arguments signifies that the corresponding parameter is a pointer output.
    /// </summary>
    internal struct ReturnBox { }


    /// <summary>
    /// Interface used for initialize function pointers.
    /// </summary>
    internal interface IFunctionPointerProvider
    {
        object FromIntPtr(IntPtr ptr);
    }

    /// <summary>
    /// Used to implement custom testing behaviour
    /// </summary>
    internal interface TestCompilerBaseExtensions
    {
        (bool shouldSkip, string skipReason) SkipTest(MethodInfo method);
        Type FetchAlternateDelegate(out bool isInRegistry, out Func<object, object[], object> caller);
        object[] ProcessNativeArgsForDelegateCaller(object[] nativeArgs, MethodInfo methodInfo);
    }

    [AttributeUsage(AttributeTargets.Method, AllowMultiple = true, Inherited = false)]
    internal abstract class TestCompilerAttributeBase : TestCaseAttribute, ITestBuilder, IWrapTestMethod
    {
        private readonly NUnitTestCaseBuilder _builder = new NUnitTestCaseBuilder();

        public const string GoldFolder = "gold/x86";
        public const string GoldFolderArm = "gold/arm";
        public const string GeneratedFolder = "generated/x86";
        public const string GeneratedFolderArm = "generated/arm";

        public TestCompilerAttributeBase(params object[] arguments) : base(arguments)
        {
        }

        /// <summary>
        /// Whether the test should only be compiled and not run. Useful for having tests that would produce infinitely running code which could ICE the compiler.
        /// </summary>
        public bool CompileOnly { get; set; }

        /// <summary>
        /// The type of exception the test expects to be thrown.
        /// </summary>
        public Type ExpectedException { get; set; }

        /// <summary>
        /// Whether the test is expected to throw a compiler exception or not.
        /// </summary>
        public bool ExpectCompilerException { get; set; }

        public bool DisableGold { get; set; }

        public DiagnosticId ExpectedDiagnosticId
        {
            get => throw new InvalidOperationException();
            set => ExpectedDiagnosticIds = new DiagnosticId[] { value };
        }

        public DiagnosticId[] ExpectedDiagnosticIds { get; set; } = new DiagnosticId[0];

        public bool FastMath { get; set; }

        /// <summary>
        /// Use this property when the JIT calculation is wrong (e.g when using float)
        /// </summary>
        public object OverrideResultOnMono { get; set; }

        /// <summary>
        /// Use this property to set the result of the managed method and skip running it completely (for example when there is no reference managed implementation)
        /// </summary>
        public object OverrideManagedResult { get; set; }

        /// <summary>
        /// Use this when a pointer is used in a sizeof computation, since on a 32bit target the result will differ versus our 64bit managed results.
        /// </summary>
        public object OverrideOn32BitNative { get; set; }

        /// <summary>
        /// Use this and specify a TargetPlatform (Host) to have the test ignored when running on that host. Mostly used by WASM at present.
        /// </summary>
        public object IgnoreOnPlatform { get; set; }

        public bool? IsDeterministic { get; set; }

        protected virtual bool SupportException => true;

        IEnumerable<TestMethod> ITestBuilder.BuildFrom(IMethodInfo method, Test suite)
        {
            // If the system doesn't support exceptions (Unity editor for delegates) we should not test with exceptions
            bool skipTest = (ExpectCompilerException || ExpectedException != null) && !SupportException;
            var expectResult = !method.ReturnType.IsType(typeof(void));
            var arguments = new List<object>(this.Arguments);

            // Expand arguments with IntRangeAttributes if we have them
            foreach (var param in method.GetParameters())
            {
                var attrs = param.GetCustomAttributes<IntRangeAttribute>(false);
                if (attrs == null || attrs.Length != 1)
                    continue;

                arguments.Add(attrs[0]);
            }

            IEnumerable<object[]> permutations = CreatePermutation(0, arguments.ToArray(), method.GetParameters());

            // TODO: Workaround for a scalability bug with R# or Rider
            // Run only one testcase if not running from the commandline
            if (!IsCommandLine())
            {
                permutations = permutations.Take(1);
            }

            foreach (var newArguments in permutations)
            {
                var caseParameters = new TestCaseParameters(newArguments);
                if (expectResult)
                {
                    caseParameters.ExpectedResult = true;
                    if (OverrideResultOnMono != null && IsMono())
                    {
                        caseParameters.Properties.Set(nameof(OverrideResultOnMono), OverrideResultOnMono);
                    }
                    if (OverrideManagedResult != null)
                    {
                        caseParameters.Properties.Set(nameof(OverrideManagedResult), OverrideManagedResult);
                    }
                    if (OverrideOn32BitNative != null)
                    {
                        caseParameters.Properties.Set(nameof(OverrideOn32BitNative), OverrideOn32BitNative);
                    }
                }

                // Transfer FastMath parameter to the compiler
                caseParameters.Properties.Set(nameof(FastMath), FastMath);

                var test = _builder.BuildTestMethod(method, suite, caseParameters);
                if (skipTest)
                {
                    test.RunState = RunState.Skipped;
                    test.Properties.Add(PropertyNames.SkipReason, "Exceptions are not supported");
                }

                yield return test;
            }
        }

        private static IEnumerable<object[]> CreatePermutation(int index, object[] args, IParameterInfo[] parameters)
        {
            if (index >= args.Length)
            {
                yield return args;
                yield break;
            }
            var copyArgs = (object[])args.Clone();
            bool hasRange = false;
            for (; index < args.Length; index++)
            {
                var arg = copyArgs[index];
                if (arg is DataRange)
                {
                    var range = (DataRange)arg;
                    // TEMP: Disable NaN test for now
                    //range = range & ~(DataRange.NaN);
                    foreach (var value in range.ExpandRange(parameters[index].ParameterType, index))
                    {
                        copyArgs[index] = value;
                        foreach (var subPermutation in CreatePermutation(index + 1, copyArgs, parameters))
                        {
                            hasRange = true;
                            yield return subPermutation;
                        }
                    }
                }
                else if (arg is IntRangeAttribute)
                {
                    var ir = (IntRangeAttribute)arg;
                    if (ir != null)
                    {
                        for (int x = ir.Lo; x <= ir.Hi; ++x)
                        {
                            copyArgs[index] = x;

                            foreach (var subPermutation in CreatePermutation(index + 1, copyArgs, parameters))
                            {
                                hasRange = true;
                                yield return subPermutation;
                            }
                        }
                    }
                }
            }
            if (!hasRange)
            {
                yield return copyArgs;
            }
        }

        TestCommand ICommandWrapper.Wrap(TestCommand command)
        {
            var testMethod = (TestMethod)command.Test;
            return GetTestCommand(this, testMethod, testMethod);
        }

        protected abstract bool IsCommandLine();

        protected abstract bool IsMono();

        protected abstract TestCompilerCommandBase GetTestCommand(TestCompilerAttributeBase attribute, Test test, TestMethod originalMethod);
    }

    internal abstract class TestCompilerCommandBase : TestCommand
    {
        protected readonly TestMethod _originalMethod;
        private readonly bool _compileOnly;
        private readonly Type _expectedException;
        protected readonly bool _expectCompilerException;
        private readonly DiagnosticId[] _expectedDiagnosticIds;

        protected virtual bool TestInterpreter => false;

        protected TestCompilerCommandBase(TestCompilerAttributeBase attribute, Test test, TestMethod originalMethod) : base(test)
        {
            _originalMethod = originalMethod;
            Attribute = attribute;
            _compileOnly = Attribute.CompileOnly;
            _expectedException = Attribute.ExpectedException;
            _expectCompilerException = Attribute.ExpectCompilerException;
            _expectedDiagnosticIds = Attribute.ExpectedDiagnosticIds;
        }

        public TestCompilerAttributeBase Attribute { get; }

        public override TestResult Execute(ExecutionContext context)
        {
            TestResult lastResult = null;
            for (int i = 0; i < GetRunCount(); i++)
            {
                lastResult = ExecuteMethod(context);
            }

            return lastResult;
        }

        protected virtual Type CreateNativeDelegateType(Type returnType, Type[] arguments, out bool isInRegistry, out Func<object, object[], object> caller)
        {
            if (GetExtension() != null)
            {
                Type type = GetExtension().FetchAlternateDelegate(out isInRegistry, out caller);
                if (type != null)
                {
                    return type;
                }
            }

            isInRegistry = false;
            StaticDelegateCallback staticDelegate;
            if (StaticDelegateRegistry.TryFind(returnType, arguments, out staticDelegate))
            {
                isInRegistry = true;
                caller = staticDelegate.Caller;
                return staticDelegate.DelegateType;
            }
            else
            {
#if BURST_TESTS_ONLY
                // Else we try to do it with a dynamic call
                var type = DelegateHelper.NewDelegateType(returnType, arguments);
                caller = StaticDynamicDelegateCaller;
                return type;
#else
                throw new Exception("Couldn't find delegate in static registry and not able to use a dynamic call.");
#endif
            }
        }

        private static Func<object, object[], object> StaticDynamicDelegateCaller = new Func<object, object[], object>((del, arguments) => ((Delegate)del).DynamicInvoke(arguments));

        private static readonly int MaxReturnBoxSize = 512;

        protected bool RunManagedBeforeNative { get; set; }

        protected static readonly Dictionary<string, string> BailedTests = new Dictionary<string, string>();

        private unsafe void ZeroMemory(byte* ptr, int size)
        {
            for (int i = 0; i < size; i++)
            {
                *(ptr + i) = 0;
            }
        }

        private unsafe TestResult ExecuteMethod(ExecutionContext context)
        {
            byte* returnBox = stackalloc byte[MaxReturnBoxSize];
            Setup();
            var methodInfo = _originalMethod.Method.MethodInfo;

            var runTest = TestOnCurrentHostEnvironment(methodInfo);

            if (runTest)
            {
                var arguments = GetArgumentsArray(_originalMethod);

                // We can't skip tests during BuildFrom that rely on specific options (e.g. current platform)
                // So we handle the remaining cases here via extensions
                if (GetExtension() != null)
                {
                    var skip = GetExtension().SkipTest(methodInfo);
                    if (skip.shouldSkip)
                    {
                        // For now, mark the tests as passed rather than skipped, to avoid the log spam
                        //On wasm this log spam accounts for 33minutes of test execution time!!
                        //context.CurrentResult.SetResult(ResultState.Skipped, skip.skipReason);
                        context.CurrentResult.SetResult(ResultState.Success);
                        return context.CurrentResult;
                    }
                }

                // If we expect a compiler exception, then we need to allow argument transformation to fail,
                // because this may be the actual thing that we're trying to test.
                object[] nativeArgs = null;
                Type[] nativeArgTypes = null;
                Type returnBoxType = null;
                var transformedArguments = false;
                if (_expectCompilerException)
                {
                    var expectedExceptionResult = TryExpectedException(
                        context,
                        () => TransformArguments(_originalMethod.Method.MethodInfo, arguments, out nativeArgs, out nativeArgTypes, returnBox, out returnBoxType),
                        "Transforming arguments",
                        type => true,
                        "Any exception",
                        false,
                        false);
                    if (expectedExceptionResult != TryExpectedExceptionResult.DidNotThrowException)
                    {
                        return context.CurrentResult;
                    }
                    transformedArguments = true;
                }

                if (!transformedArguments)
                {
                    TransformArguments(_originalMethod.Method.MethodInfo, arguments, out nativeArgs, out nativeArgTypes, returnBox, out returnBoxType);
                }

                bool isInRegistry = false;
                Func<object, object[], object> nativeDelegateCaller;
                var delegateType = CreateNativeDelegateType(_originalMethod.Method.MethodInfo.ReturnType, nativeArgTypes, out isInRegistry, out nativeDelegateCaller);
                if (!isInRegistry)
                {
                    TestContext.Out.WriteLine($"Warning, the delegate for the method `{_originalMethod.Method}` has not been generated");
                }

                Delegate compiledFunction;
                Delegate interpretDelegate;
                try
                {
                    compiledFunction = CompileDelegate(context, methodInfo, delegateType, returnBox, out _, out interpretDelegate);
                }
                catch (Exception ex) when (_expectedException != null && ex.GetType() == _expectedException)
                {
                    context.CurrentResult.SetResult(ResultState.Success);
                    return context.CurrentResult;
                }

                Assert.IsTrue(returnBoxType == null || Marshal.SizeOf(returnBoxType) <= MaxReturnBoxSize);

                if (compiledFunction == null)
                    return context.CurrentResult;

                if (_compileOnly) // If the test only wants to compile the code, bail now.
                {
                    context.CurrentResult.SetResult(ResultState.Success);
                    return context.CurrentResult;
                }
                else if (_expectedException != null) // Special case if we have an expected exception
                {
                    if (TryExpectedException(context, () => _originalMethod.Method.Invoke(context.TestObject, arguments), ".NET", type => type == _expectedException, _expectedException.FullName, false) != TryExpectedExceptionResult.ThrewExpectedException)
                    {
                        return context.CurrentResult;
                    }

                    if (TryExpectedException(context, () => nativeDelegateCaller(compiledFunction, nativeArgs), "Native", type => type == _expectedException, _expectedException.FullName, true) != TryExpectedExceptionResult.ThrewExpectedException)
                    {
                        return context.CurrentResult;
                    }
                }
                else
                {
                    object resultNative = null;

                    // We are forced to run native before managed, because on IL2CPP, if a parameter
                    // is a ref, it will keep the same memory location for both managed and burst
                    // while in .NET CLR we have a different behavior
                    // The result is that on functions expecting the same input value through the ref
                    // it won't be anymore true because the managed could have modified the value before
                    // burst

                    // ------------------------------------------------------------------
                    // Run Native (Before)
                    // ------------------------------------------------------------------
                    if (!RunManagedBeforeNative && !TestInterpreter)
                    {
                        if (GetExtension() != null)
                        {
                            nativeArgs = GetExtension().ProcessNativeArgsForDelegateCaller(nativeArgs, methodInfo);
                        }
                        resultNative = nativeDelegateCaller(compiledFunction, nativeArgs);
                        if (returnBoxType != null)
                        {
                            resultNative = Marshal.PtrToStructure((IntPtr)returnBox, returnBoxType);
                        }
                    }

                    // ------------------------------------------------------------------
                    // Run Interpreter
                    // ------------------------------------------------------------------
                    object resultInterpreter = null;

                    if (TestInterpreter)
                    {
                        ZeroMemory(returnBox, MaxReturnBoxSize);
                        var name = methodInfo.DeclaringType.FullName + "." + methodInfo.Name;
                        if (!InterpretMethod(interpretDelegate, methodInfo, nativeArgs, methodInfo.ReturnType,
                            out var reason, out resultInterpreter))
                        {
                            lock (BailedTests)
                            {
                                BailedTests[name] = reason;
                            }
                        }
                        else
                        {
                            if (returnBoxType != null)
                            {
                                resultInterpreter = Marshal.PtrToStructure((IntPtr)returnBox, returnBoxType);
                            }
                        }
                    }


                    // ------------------------------------------------------------------
                    // Run Managed
                    // ------------------------------------------------------------------
                    object resultClr;
                    // This option skips running the managed version completely
                    var overrideManagedResult = _originalMethod.Properties.Get("OverrideManagedResult");
                    if (overrideManagedResult != null)
                    {
                        TestContext.Out.WriteLine($"Using OverrideManagedResult: `{overrideManagedResult}` to compare to burst `{resultNative}`, managed version not run");
                        resultClr = overrideManagedResult;
                    }
                    else
                    {
                        ZeroMemory(returnBox, MaxReturnBoxSize);
                        resultClr = _originalMethod.Method.Invoke(context.TestObject, arguments);

                        if (returnBoxType != null)
                        {
                            resultClr = Marshal.PtrToStructure((IntPtr)returnBox, returnBoxType);
                        }
                    }

                    var overrideResultOnMono = _originalMethod.Properties.Get("OverrideResultOnMono");
                    if (overrideResultOnMono != null)
                    {
                        TestContext.Out.WriteLine($"Using OverrideResultOnMono: `{overrideResultOnMono}` instead of `{resultClr}` compare to burst `{resultNative}`");
                        resultClr = overrideResultOnMono;
                    }

                    var overrideOn32BitNative = _originalMethod.Properties.Get("OverrideOn32BitNative");
                    if (overrideOn32BitNative != null && TargetIs32Bit())
                    {
                        TestContext.Out.WriteLine($"Using OverrideOn32BitNative: '{overrideOn32BitNative}' instead of '{resultClr}' compare to burst '{resultNative}' due to 32bit native runtime");
                        resultClr = overrideOn32BitNative;
                    }

                    // ------------------------------------------------------------------
                    // Run Native (After)
                    // ------------------------------------------------------------------
                    if (RunManagedBeforeNative && !TestInterpreter)
                    {
                        ZeroMemory(returnBox, MaxReturnBoxSize);
                        resultNative = nativeDelegateCaller(compiledFunction, nativeArgs);
                        if (returnBoxType != null)
                        {
                            resultNative = Marshal.PtrToStructure((IntPtr)returnBox, returnBoxType);
                        }
                    }

                    if (!TestInterpreter)
                    {
                        // Use our own version (for handling correctly float precision)
                        AssertHelper.AreEqual(resultClr, resultNative, GetULP());
                    }
                    else if (resultInterpreter != null)
                    {
                        AssertHelper.AreEqual(resultClr, resultInterpreter, GetULP());
                    }

                    // Validate deterministic outputs - Disabled for now
                    //RunDeterminismValidation(_originalMethod, resultNative);

                    // Allow to process native result
                    ProcessNativeResult(_originalMethod, resultNative);

                    context.CurrentResult.SetResult(ResultState.Success);

                    PostAssert(context);
                }

                // Check that the method is actually in the registry
                Assert.True(isInRegistry, "The test method is not in the registry, recompile the project with the updated StaticDelegateRegistry.generated.cs");

                // Make an attempt to clean up arguments (to reduce wasted native heap memory)
                DisposeObjects(arguments);
                DisposeObjects(nativeArgs);
            }

            // Compile the method once again, this time for Arm CPU to check against gold asm images
            GoldFileTestForOtherPlatforms(methodInfo, runTest);

            CompleteTest(context);

            return context.CurrentResult;
        }

        protected virtual void PostAssert(ExecutionContext context)
        {
        }

        protected virtual void ProcessNativeResult(TestMethod method, object result)
        {
        }
        protected virtual string GetLinesFromDeterminismLog()
        {
            return "";
        }
        protected virtual bool IsDeterministicTest(TestMethod method)
        {
            return false;
        }

        private static void DisposeObjects(object[] arguments)
        {
            foreach (object o in arguments)
            {
                IDisposable disp = o as IDisposable;
                disp?.Dispose();
            }
        }

        private object[] CloneArguments(object[] arguments)
        {
            var newArguments = new object[arguments.Length];
            for (int i = 0; i < arguments.Length; i++)
            {
                newArguments[i] = arguments[i];
            }
            return newArguments;
        }

        protected unsafe void TransformArguments(MethodInfo method, object[] args, out object[] nativeArgs, out Type[] nativeArgTypes, byte* returnBox, out Type returnBoxType)
        {
            returnBoxType = null;

            // Transform Arguments if necessary
            nativeArgs = (object[])args.Clone();

            for (var i = 0; i < nativeArgs.Length; i++)
            {
                var arg = args[i];
                if (arg == null)
                {
                    throw new AssertionException($"Argument number `{i}` for method `{method}` cannot be null");
                }

                if (arg.GetType() == typeof(float[]))
                {
                    args[i] = ConvertToNativeArray((float[])arg);
                }
                else if (arg.GetType() == typeof(int[]))
                {
                    args[i] = ConvertToNativeArray((int[])arg);
                }
                else if (arg.GetType() == typeof(float3[]))
                {
                    args[i] = ConvertToNativeArray((float3[])arg);
                }
                else if (arg is Type)
                {
                    var attrType = (Type)arg;
                    if (typeof(IArgumentProvider).IsAssignableFrom(attrType))
                    {
                        var argumentProvider = (IArgumentProvider)Activator.CreateInstance(attrType);
                        // Duplicate the input for C#/Burst in case the code is modifying the data
                        args[i] = argumentProvider.Value;
                        nativeArgs[i] = argumentProvider.Value;
                    }
                    else if (typeof(ReturnBox).IsAssignableFrom(attrType))
                    {
                        args[i] = (IntPtr)returnBox;
                        nativeArgs[i] = (IntPtr)returnBox;
                    }
                }
            }

            var parameters = method.GetParameters();
            nativeArgTypes = new Type[nativeArgs.Length];
            for (var i = 0; i < parameters.Length; i++)
            {
                var expectedArgType = parameters[i].ParameterType;
                var actualArgType = args[i].GetType();
                var actualNativeArgType = nativeArgs[i].GetType();

                if (typeof(IFunctionPointerProvider).IsAssignableFrom(expectedArgType) || (expectedArgType.IsByRef && typeof(IFunctionPointerProvider).IsAssignableFrom(expectedArgType.GetElementType())) && actualNativeArgType == typeof(string))
                {
                    var methodName = (string)args[i];
                    var candidates =
                        _originalMethod.Method.MethodInfo.DeclaringType?
                            .GetMethods()
                            .Where(x => x.IsStatic && x.Name.Equals(methodName))
                            .ToArray();

                    if (candidates == null || candidates.Length != 1)
                    {
                        throw new ArgumentException($"Could not resolve an unambigoues static method from name {methodName}.");
                    }

                    var functionPointer = CompileFunctionPointer(candidates[0], expectedArgType.IsByRef ? expectedArgType.GetElementType() : expectedArgType);
                    nativeArgs[i] = functionPointer;
                    args[i] = functionPointer;
                    actualNativeArgType = expectedArgType;
                    actualArgType = expectedArgType;
                }
                else
                {
                    // If the expected parameter for the native is a reference, we need to specify it here
                    if (expectedArgType.IsByRef)
                    {
                        actualArgType = actualArgType.MakeByRefType();
                        actualNativeArgType = actualNativeArgType.MakeByRefType();
                    }
                    if (expectedArgType == typeof(IntPtr) && actualNativeArgType == typeof(int))
                    {
                        nativeArgs[i] = new IntPtr((int)args[i]);
                        args[i] = new IntPtr((int)args[i]);
                        actualNativeArgType = typeof(IntPtr);
                        actualArgType = typeof(IntPtr);
                    }
                    if (expectedArgType == typeof(UIntPtr) && actualNativeArgType == typeof(uint))
                    {
                        nativeArgs[i] = new UIntPtr((uint)args[i]);
                        args[i] = new UIntPtr((uint)args[i]);
                        actualNativeArgType = typeof(UIntPtr);
                        actualArgType = typeof(UIntPtr);
                    }
                    if (expectedArgType.IsPointer && actualNativeArgType == typeof(IntPtr))
                    {
                        if ((IntPtr)args[i] == (IntPtr)returnBox)
                        {
                            if (returnBoxType != null)
                            {
                                throw new ArgumentException($"Only one ReturnBox allowed");
                            }
                            returnBoxType = expectedArgType.GetElementType();
                        }

                        nativeArgs[i] = args[i];
                        actualNativeArgType = expectedArgType;
                        actualArgType = expectedArgType;
                    }
                }

                nativeArgTypes[i] = actualNativeArgType;

                if (expectedArgType != actualArgType)
                {
                    throw new ArgumentException($"Type mismatch in parameter {i} passed to {method.Name}: expected {expectedArgType}, got {actualArgType}.");
                }
            }
        }

        private static NativeArray<T> ConvertToNativeArray<T>(T[] array) where T : struct
        {
            var nativeArray = new NativeArray<T>(array.Length, Allocator.Persistent);
            for (var j = 0; j < array.Length; j++)
                nativeArray[j] = array[j];
            return nativeArray;
        }

        protected enum TryExpectedExceptionResult
        {
            ThrewExpectedException,
            ThrewUnexpectedException,
            DidNotThrowException,
        }

        protected TryExpectedExceptionResult TryExpectedException(ExecutionContext context, Action action, string contextName, Func<Type, bool> expectedException, string expectedExceptionName, bool isTargetException, bool requireException = true)
        {
            Type caughtType = null;

            Exception caughtException = null;
            try
            {
                action();
            }
            catch (Exception ex)
            {
                if (isTargetException && ex is TargetInvocationException)
                {
                    ex = ((TargetInvocationException)ex).InnerException;
                }
                if (ex is NUnitException)
                    ex = ex.InnerException;
                caughtException = ex;
                if (caughtException != null)
                {
                    caughtType = caughtException.GetType();
                }
            }

            if (caughtException == null && !requireException)
            {
                return TryExpectedExceptionResult.DidNotThrowException;
            }

            if (caughtType != null && expectedException(caughtType))
            {
                if (!CheckExpectedDiagnostics(context, contextName))
                {
                    return TryExpectedExceptionResult.ThrewUnexpectedException;
                }
                else
                {
                    context.CurrentResult.SetResult(ResultState.Success);
                    return TryExpectedExceptionResult.ThrewExpectedException;
                }
            }
            else if (caughtType != null)
            {
                context.CurrentResult.SetResult(ResultState.Failure, $"In {contextName} code, expected {expectedExceptionName} but got {caughtType.Name}. Exception: {caughtException}");
                return TryExpectedExceptionResult.ThrewUnexpectedException;
            }
            else
            {
                context.CurrentResult.SetResult(ResultState.Failure, $"In {contextName} code, expected {expectedExceptionName} but no exception was thrown");
                return TryExpectedExceptionResult.ThrewUnexpectedException;
            }
        }

        private static string GetDiagnosticIds(IEnumerable<DiagnosticId> diagnosticIds)
        {
            if (diagnosticIds.Count() == 0)
            {
                return "None";
            }
            else
            {
                return string.Join(",", diagnosticIds);
            }
        }

        public static void ReportBailedTests(TextWriter writer = null)
        {
            writer = writer ?? Console.Out;
            lock (BailedTests)
            {
                foreach (var bailedTest in BailedTests.OrderBy(kv => kv.Key))
                {
                    writer.WriteLine($"{bailedTest.Key}: {bailedTest.Value}");
                }
            }
        }

        protected bool CheckExpectedDiagnostics(ExecutionContext context, string contextName)
        {
            var loggedDiagnosticIds = GetLoggedDiagnosticIds().OrderBy(x => x);
            var expectedDiagnosticIds = _expectedDiagnosticIds.OrderBy(x => x);

            if (!loggedDiagnosticIds.SequenceEqual(expectedDiagnosticIds))
            {
                context.CurrentResult.SetResult(ResultState.Failure, $"In {contextName} code, expecting diagnostic(s) to be logged with IDs {GetDiagnosticIds(_expectedDiagnosticIds)} but instead the following diagnostic(s) were logged: {GetDiagnosticIds(loggedDiagnosticIds)}");
                return false;
            }
            return true;
        }

        protected virtual IEnumerable<DiagnosticId> GetLoggedDiagnosticIds() => Array.Empty<DiagnosticId>();
        protected virtual IEnumerable<DiagnosticId> GetExpectedDiagnosticIds() => _expectedDiagnosticIds;

        protected void RunDeterminismValidation(TestMethod method, object resultNative)
        {
            // GetLines first as this will allow us to ignore these tests if the log file is missing
            //which occurs when running the "trunk" package tests, since they use their own project file
            //a possible workaround for this is to embed the log into a .cs file and stick that in the tests
            //folder, then we don't need the resource folder version.
            var lines = GetLinesFromDeterminismLog();

            // If the log is not found, this will also return false
            if (!IsDeterministicTest(method))
                return;

            var allLines = lines.Split(new char[] { '\r', '\n' });
            string matchName = $"{method.FullName}:";
            foreach (var line in allLines)
            {
                if (line.StartsWith(matchName))
                {
                    if (resultNative.GetType() == typeof(Single))
                    {
                        unsafe
                        {
                            var val = (float)resultNative;
                            int intvalue = *((int*)&val);
                            var resStr = $"0x{intvalue:X4}";

                            if (!line.EndsWith(resStr))
                            {
                                Assert.Fail($"Deterministic mismatch '{method.FullName}: {resStr}' but expected '{line}'");
                            }
                        }
                    }
                    else
                    {
                        Assert.That(resultNative.GetType() == typeof(Double));
                        unsafe
                        {
                            var val = (double)resultNative;
                            long longvalue = *((long*)&val);
                            var resStr = $"0x{longvalue:X8}";

                            if (!line.EndsWith(resStr))
                            {
                                Assert.Fail($"Deterministic mismatch '{method.FullName}: {resStr}' but expected '{line}'");
                            }
                        }
                    }
                    return;
                }
            }
            Assert.Fail($"Deterministic mismatch test not present : '{method.FullName}'");
        }

        protected abstract int GetRunCount();

        protected abstract void CompleteTest(ExecutionContext context);

        protected abstract int GetULP();

        protected abstract object[] GetArgumentsArray(TestMethod method);

        protected abstract unsafe Delegate CompileDelegate(ExecutionContext context, MethodInfo methodInfo, Type delegateType, byte* returnBox, out Type returnBoxType, out Delegate interpretDelegate);

        protected abstract bool InterpretMethod(Delegate interpretDelegate, MethodInfo methodInfo, object[] args, Type returnType, out string reason, out object result);

        protected abstract void GoldFileTestForOtherPlatforms(MethodInfo methodInfo, bool testWasRun);

        protected abstract bool TestOnCurrentHostEnvironment(MethodInfo methodInfo);

        protected abstract object CompileFunctionPointer(MethodInfo methodInfo, Type functionType);

        protected abstract void Setup();

        protected abstract TestResult HandleCompilerException(ExecutionContext context, MethodInfo methodInfo);

        protected abstract TestCompilerBaseExtensions GetExtension();

        protected abstract bool TargetIs32Bit();
    }

    [AttributeUsage(AttributeTargets.Parameter, AllowMultiple = false, Inherited = false)]
    internal sealed class IntRangeAttribute : Attribute
    {
        public readonly int Lo;
        public readonly int Hi;

        public IntRangeAttribute(int hi) { Hi = hi; }
        public IntRangeAttribute(int lo, int hi) { Lo = lo; Hi = hi; }
    }
}