// 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.


// This file defines an internal class used to throw exceptions in BCL code.
// The main purpose is to reduce code size. 
// 
// The old way to throw an exception generates quite a lot IL code and assembly code.
// Following is an example:
//     C# source
//          throw new ArgumentNullException(nameof(key), SR.ArgumentNull_Key);
//     IL code:
//          IL_0003:  ldstr      "key"
//          IL_0008:  ldstr      "ArgumentNull_Key"
//          IL_000d:  call       string System.Environment::GetResourceString(string)
//          IL_0012:  newobj     instance void System.ArgumentNullException::.ctor(string,string)
//          IL_0017:  throw
//    which is 21bytes in IL.
// 
// So we want to get rid of the ldstr and call to Environment.GetResource in IL.
// In order to do that, I created two enums: ExceptionResource, ExceptionArgument to represent the
// argument name and resource name in a small integer. The source code will be changed to 
//    ThrowHelper.ThrowArgumentNullException(ExceptionArgument.key, ExceptionResource.ArgumentNull_Key);
//
// The IL code will be 7 bytes.
//    IL_0008:  ldc.i4.4
//    IL_0009:  ldc.i4.4
//    IL_000a:  call       void System.ThrowHelper::ThrowArgumentNullException(valuetype System.ExceptionArgument)
//    IL_000f:  ldarg.0
//
// This will also reduce the Jitted code size a lot. 
//
// It is very important we do this for generic classes because we can easily generate the same code 
// multiple times for different instantiation. 
// 

using System.Buffers;
using System.Collections.Generic;
using System.Diagnostics;
using System.Runtime.CompilerServices;
using System.Runtime.Serialization;

namespace System
{
    [StackTraceHidden]
    internal static class ThrowHelper
    {
        internal static void ThrowArrayTypeMismatchException()
        {
            throw new ArrayTypeMismatchException();
        }

        internal static void ThrowInvalidTypeWithPointersNotSupported(Type targetType)
        {
            throw new ArgumentException(SR.Format(SR.Argument_InvalidTypeWithPointersNotSupported, targetType));
        }

        internal static void ThrowIndexOutOfRangeException()
        {
            throw new IndexOutOfRangeException();
        }

        internal static void ThrowArgumentOutOfRangeException()
        {
            throw new ArgumentOutOfRangeException();
        }

        internal static void ThrowArgumentOutOfRangeException(ExceptionArgument argument)
        {
            throw new ArgumentOutOfRangeException(GetArgumentName(argument));
        }

        private static ArgumentOutOfRangeException GetArgumentOutOfRangeException(ExceptionArgument argument, ExceptionResource resource)
        {
            return new ArgumentOutOfRangeException(GetArgumentName(argument), GetResourceString(resource));
        }
        internal static void ThrowArgumentOutOfRangeException(ExceptionArgument argument, ExceptionResource resource)
        {
            throw GetArgumentOutOfRangeException(argument, resource);
        }
        internal static void ThrowStartIndexArgumentOutOfRange_ArgumentOutOfRange_Index()
        {
            throw GetArgumentOutOfRangeException(ExceptionArgument.startIndex,
                                                    ExceptionResource.ArgumentOutOfRange_Index);
        }
        internal static void ThrowCountArgumentOutOfRange_ArgumentOutOfRange_Count()
        {
            throw GetArgumentOutOfRangeException(ExceptionArgument.count,
                                                    ExceptionResource.ArgumentOutOfRange_Count);
        }

        internal static void ThrowArgumentException_DestinationTooShort()
        {
            throw new ArgumentException(SR.Argument_DestinationTooShort);
        }
        internal static void ThrowArgumentException_OverlapAlignmentMismatch()
        {
            throw new ArgumentException(SR.Argument_OverlapAlignmentMismatch);
        }

        internal static void ThrowArgumentException_CannotExtractScalar(ExceptionArgument argument)
        {
            throw GetArgumentException(ExceptionResource.Argument_CannotExtractScalar, argument);
        }

        internal static void ThrowArgumentOutOfRange_IndexException()
        {
            throw GetArgumentOutOfRangeException(ExceptionArgument.index,
                                                    ExceptionResource.ArgumentOutOfRange_Index);
        }
        internal static void ThrowIndexArgumentOutOfRange_NeedNonNegNumException()
        {
            throw GetArgumentOutOfRangeException(ExceptionArgument.index,
                                                    ExceptionResource.ArgumentOutOfRange_NeedNonNegNum);
        }
        internal static void ThrowValueArgumentOutOfRange_NeedNonNegNumException()
        {
            throw GetArgumentOutOfRangeException(ExceptionArgument.value,
                                                    ExceptionResource.ArgumentOutOfRange_NeedNonNegNum);
        }

        private static ArgumentException GetWrongKeyTypeArgumentException(object key, Type targetType)
        {
            return new ArgumentException(SR.Format(SR.Arg_WrongType, key, targetType), nameof(key));
        }
        internal static void ThrowWrongKeyTypeArgumentException(object key, Type targetType)
        {
            throw GetWrongKeyTypeArgumentException(key, targetType);
        }

        private static ArgumentException GetWrongValueTypeArgumentException(object value, Type targetType)
        {
            return new ArgumentException(SR.Format(SR.Arg_WrongType, value, targetType), nameof(value));
        }
        internal static void ThrowWrongValueTypeArgumentException(object value, Type targetType)
        {
            throw GetWrongValueTypeArgumentException(value, targetType);
        }

        private static ArgumentException GetAddingDuplicateWithKeyArgumentException(object key)
        {
            return new ArgumentException(SR.Format(SR.Argument_AddingDuplicate, key));
        }
        internal static void ThrowAddingDuplicateWithKeyArgumentException(object key)
        {
            throw GetAddingDuplicateWithKeyArgumentException(key);
        }

        private static KeyNotFoundException GetKeyNotFoundException(object key)
        {
            throw new KeyNotFoundException(SR.Format(SR.Arg_KeyNotFoundWithKey, key.ToString()));
        }
        internal static void ThrowKeyNotFoundException(object key)
        {
            throw GetKeyNotFoundException(key);
        }

        internal static void ThrowArgumentException(ExceptionResource resource)
        {
            throw new ArgumentException(GetResourceString(resource));
        }

        private static ArgumentException GetArgumentException(ExceptionResource resource, ExceptionArgument argument)
        {
            return new ArgumentException(GetResourceString(resource), GetArgumentName(argument));
        }
        internal static void ThrowArgumentException(ExceptionResource resource, ExceptionArgument argument)
        {
            throw GetArgumentException(resource, argument);
        }

        internal static void ThrowAggregateException(List<Exception> exceptions)
        {
            throw new AggregateException(exceptions);
        }

        internal static void ThrowArgumentException_Argument_InvalidArrayType()
        {
            throw new ArgumentException(SR.Argument_InvalidArrayType);
        }

        internal static void ThrowArgumentNullException(ExceptionArgument argument)
        {
            throw new ArgumentNullException(GetArgumentName(argument));
        }

        internal static void ThrowInvalidOperationException(ExceptionResource resource)
        {
            throw new InvalidOperationException(GetResourceString(resource));
        }

        internal static void ThrowInvalidOperationException_OutstandingReferences()
        {
            throw new InvalidOperationException(SR.Memory_OutstandingReferences);
        }

        internal static void ThrowInvalidOperationException_InvalidOperation_EnumFailedVersion()
        {
            throw new InvalidOperationException(SR.InvalidOperation_EnumFailedVersion);
        }

        internal static void ThrowInvalidOperationException_InvalidOperation_EnumOpCantHappen()
        {
            throw new InvalidOperationException(SR.InvalidOperation_EnumOpCantHappen);
        }

        internal static void ThrowInvalidOperationException_InvalidOperation_EnumNotStarted()
        {
            throw new InvalidOperationException(SR.InvalidOperation_EnumNotStarted);
        }

        internal static void ThrowInvalidOperationException_InvalidOperation_EnumEnded()
        {
            throw new InvalidOperationException(SR.InvalidOperation_EnumEnded);
        }

        internal static void ThrowInvalidOperationException_InvalidOperation_NoValue()
        {
            throw new InvalidOperationException(SR.InvalidOperation_NoValue);
        }

        internal static void ThrowInvalidOperationException_ConcurrentOperationsNotSupported()
        {
            throw new InvalidOperationException(SR.InvalidOperation_ConcurrentOperationsNotSupported);
        }

        internal static void ThrowSerializationException(ExceptionResource resource)
        {
            throw new SerializationException(GetResourceString(resource));
        }

        internal static void ThrowObjectDisposedException(ExceptionResource resource)
        {
            throw new ObjectDisposedException(null, GetResourceString(resource));
        }

        internal static void ThrowNotSupportedException()
        {
            throw new NotSupportedException();
        }

        internal static void ThrowNotSupportedException(ExceptionResource resource)
        {
            throw new NotSupportedException(GetResourceString(resource));
        }

        private static Exception GetArraySegmentCtorValidationFailedException(Array array, int offset, int count)
        {
            if (array == null)
                return new ArgumentNullException(nameof(array));
            if (offset < 0)
                return new ArgumentOutOfRangeException(nameof(offset), SR.ArgumentOutOfRange_NeedNonNegNum);
            if (count < 0)
                return new ArgumentOutOfRangeException(nameof(count), SR.ArgumentOutOfRange_NeedNonNegNum);

            Debug.Assert(array.Length - offset < count);
            return new ArgumentException(SR.Argument_InvalidOffLen);
        }
        internal static void ThrowArraySegmentCtorValidationFailedExceptions(Array array, int offset, int count)
        {
            throw GetArraySegmentCtorValidationFailedException(array, offset, count);
        }

        internal static void ThrowFormatException_BadFormatSpecifier()
        {
            throw new FormatException(SR.Argument_BadFormatSpecifier);
        }

        internal static void ThrowArgumentOutOfRangeException_PrecisionTooLarge()
        {
            throw new ArgumentOutOfRangeException("precision", SR.Format(SR.Argument_PrecisionTooLarge, StandardFormat.MaxPrecision));
        }

        internal static void ThrowArgumentOutOfRangeException_SymbolDoesNotFit()
        {
            throw new ArgumentOutOfRangeException("symbol", SR.Argument_BadFormatSpecifier);
        }

        // Allow nulls for reference types and Nullable<U>, but not for value types.
        // Aggressively inline so the jit evaluates the if in place and either drops the call altogether
        // Or just leaves null test and call to the Non-returning ThrowHelper.ThrowArgumentNullException
        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        internal static void IfNullAndNullsAreIllegalThenThrow<T>(object value, ExceptionArgument argName)
        {
            // Note that default(T) is not equal to null for value types except when T is Nullable<U>. 
            if (!(default(T) == null) && value == null)
                ThrowHelper.ThrowArgumentNullException(argName);
        }

        private static string GetArgumentName(ExceptionArgument argument)
        {
            switch (argument)
            {
                case ExceptionArgument.obj:
                    return "obj";
                case ExceptionArgument.dictionary:
                    return "dictionary";
                case ExceptionArgument.array:
                    return "array";
                case ExceptionArgument.info:
                    return "info";
                case ExceptionArgument.key:
                    return "key";
                case ExceptionArgument.text:
                    return "text";
                case ExceptionArgument.values:
                    return "values";
                case ExceptionArgument.value:
                    return "value";
                case ExceptionArgument.startIndex:
                    return "startIndex";
                case ExceptionArgument.task:
                    return "task";
                case ExceptionArgument.ch:
                    return "ch";
                case ExceptionArgument.s:
                    return "s";
                case ExceptionArgument.input:
                    return "input";
                case ExceptionArgument.ownedMemory:
                    return "ownedMemory";
                case ExceptionArgument.list:
                    return "list";
                case ExceptionArgument.index:
                    return "index";
                case ExceptionArgument.capacity:
                    return "capacity";
                case ExceptionArgument.collection:
                    return "collection";
                case ExceptionArgument.item:
                    return "item";
                case ExceptionArgument.converter:
                    return "converter";
                case ExceptionArgument.match:
                    return "match";
                case ExceptionArgument.count:
                    return "count";
                case ExceptionArgument.action:
                    return "action";
                case ExceptionArgument.comparison:
                    return "comparison";
                case ExceptionArgument.exceptions:
                    return "exceptions";
                case ExceptionArgument.exception:
                    return "exception";
                case ExceptionArgument.pointer:
                    return "pointer";
                case ExceptionArgument.start:
                    return "start";
                case ExceptionArgument.format:
                    return "format";
                case ExceptionArgument.culture:
                    return "culture";
                case ExceptionArgument.comparer:
                    return "comparer";
                case ExceptionArgument.comparable:
                    return "comparable";
                case ExceptionArgument.source:
                    return "source";
                case ExceptionArgument.state:
                    return "state";
                case ExceptionArgument.length:
                    return "length";
                case ExceptionArgument.comparisonType:
                    return "comparisonType";
                case ExceptionArgument.manager:
                    return "manager";
                case ExceptionArgument.sourceBytesToCopy:
                    return "sourceBytesToCopy";
                case ExceptionArgument.callBack:
                    return "callBack";
                case ExceptionArgument.creationOptions:
                    return "creationOptions";
                case ExceptionArgument.function:
                    return "function";
                case ExceptionArgument.scheduler:
                    return "scheduler";
                case ExceptionArgument.continuationAction:
                    return "continuationAction";
                case ExceptionArgument.continuationFunction:
                    return "continuationFunction";
                case ExceptionArgument.tasks:
                    return "tasks";
                case ExceptionArgument.asyncResult:
                    return "asyncResult";
                case ExceptionArgument.beginMethod:
                    return "beginMethod";
                case ExceptionArgument.endMethod:
                    return "endMethod";
                case ExceptionArgument.endFunction:
                    return "endFunction";
                case ExceptionArgument.cancellationToken:
                    return "cancellationToken";
                case ExceptionArgument.continuationOptions:
                    return "continuationOptions";
                case ExceptionArgument.delay:
                    return "delay";
                case ExceptionArgument.millisecondsDelay:
                    return "millisecondsDelay";
                case ExceptionArgument.millisecondsTimeout:
                    return "millisecondsTimeout";
                case ExceptionArgument.stateMachine:
                    return "stateMachine";
                case ExceptionArgument.timeout:
                    return "timeout";
                default:
                    Debug.Fail("The enum value is not defined, please check the ExceptionArgument Enum.");
                    return "";
            }
        }

        private static string GetResourceString(ExceptionResource resource)
        {
            switch (resource)
            {
                case ExceptionResource.Argument_InvalidArgumentForComparison:
                    return SR.Argument_InvalidArgumentForComparison;
                case ExceptionResource.ArgumentOutOfRange_Index:
                    return SR.ArgumentOutOfRange_Index;
                case ExceptionResource.ArgumentOutOfRange_Count:
                    return SR.ArgumentOutOfRange_Count;
                case ExceptionResource.Arg_ArrayPlusOffTooSmall:
                    return SR.Arg_ArrayPlusOffTooSmall;
                case ExceptionResource.NotSupported_ReadOnlyCollection:
                    return SR.NotSupported_ReadOnlyCollection;
                case ExceptionResource.Arg_RankMultiDimNotSupported:
                    return SR.Arg_RankMultiDimNotSupported;
                case ExceptionResource.Arg_NonZeroLowerBound:
                    return SR.Arg_NonZeroLowerBound;
                case ExceptionResource.ArgumentOutOfRange_ListInsert:
                    return SR.ArgumentOutOfRange_ListInsert;
                case ExceptionResource.ArgumentOutOfRange_NeedNonNegNum:
                    return SR.ArgumentOutOfRange_NeedNonNegNum;
                case ExceptionResource.ArgumentOutOfRange_SmallCapacity:
                    return SR.ArgumentOutOfRange_SmallCapacity;
                case ExceptionResource.Argument_InvalidOffLen:
                    return SR.Argument_InvalidOffLen;
                case ExceptionResource.Argument_CannotExtractScalar:
                    return SR.Argument_CannotExtractScalar;
                case ExceptionResource.ArgumentOutOfRange_BiggerThanCollection:
                    return SR.ArgumentOutOfRange_BiggerThanCollection;
                case ExceptionResource.Serialization_MissingKeys:
                    return SR.Serialization_MissingKeys;
                case ExceptionResource.Serialization_NullKey:
                    return SR.Serialization_NullKey;
                case ExceptionResource.NotSupported_KeyCollectionSet:
                    return SR.NotSupported_KeyCollectionSet;
                case ExceptionResource.NotSupported_ValueCollectionSet:
                    return SR.NotSupported_ValueCollectionSet;
                case ExceptionResource.InvalidOperation_NullArray:
                    return SR.InvalidOperation_NullArray;
                case ExceptionResource.TaskT_TransitionToFinal_AlreadyCompleted:
                    return SR.TaskT_TransitionToFinal_AlreadyCompleted;
                case ExceptionResource.TaskCompletionSourceT_TrySetException_NullException:
                    return SR.TaskCompletionSourceT_TrySetException_NullException;
                case ExceptionResource.TaskCompletionSourceT_TrySetException_NoExceptions:
                    return SR.TaskCompletionSourceT_TrySetException_NoExceptions;
                case ExceptionResource.NotSupported_StringComparison:
                    return SR.NotSupported_StringComparison;
                case ExceptionResource.ConcurrentCollection_SyncRoot_NotSupported:
                    return SR.ConcurrentCollection_SyncRoot_NotSupported;
                case ExceptionResource.Task_MultiTaskContinuation_NullTask:
                    return SR.Task_MultiTaskContinuation_NullTask;
                case ExceptionResource.InvalidOperation_WrongAsyncResultOrEndCalledMultiple:
                    return SR.InvalidOperation_WrongAsyncResultOrEndCalledMultiple;
                case ExceptionResource.Task_MultiTaskContinuation_EmptyTaskList:
                    return SR.Task_MultiTaskContinuation_EmptyTaskList;
                case ExceptionResource.Task_Start_TaskCompleted:
                    return SR.Task_Start_TaskCompleted;
                case ExceptionResource.Task_Start_Promise:
                    return SR.Task_Start_Promise;
                case ExceptionResource.Task_Start_ContinuationTask:
                    return SR.Task_Start_ContinuationTask;
                case ExceptionResource.Task_Start_AlreadyStarted:
                    return SR.Task_Start_AlreadyStarted;
                case ExceptionResource.Task_RunSynchronously_Continuation:
                    return SR.Task_RunSynchronously_Continuation;
                case ExceptionResource.Task_RunSynchronously_Promise:
                    return SR.Task_RunSynchronously_Promise;
                case ExceptionResource.Task_RunSynchronously_TaskCompleted:
                    return SR.Task_RunSynchronously_TaskCompleted;
                case ExceptionResource.Task_RunSynchronously_AlreadyStarted:
                    return SR.Task_RunSynchronously_AlreadyStarted;
                case ExceptionResource.AsyncMethodBuilder_InstanceNotInitialized:
                    return SR.AsyncMethodBuilder_InstanceNotInitialized;
                case ExceptionResource.Task_ContinueWith_ESandLR:
                    return SR.Task_ContinueWith_ESandLR;
                case ExceptionResource.Task_ContinueWith_NotOnAnything:
                    return SR.Task_ContinueWith_NotOnAnything;
                case ExceptionResource.Task_Delay_InvalidDelay:
                    return SR.Task_Delay_InvalidDelay;
                case ExceptionResource.Task_Delay_InvalidMillisecondsDelay:
                    return SR.Task_Delay_InvalidMillisecondsDelay;
                case ExceptionResource.Task_Dispose_NotCompleted:
                    return SR.Task_Dispose_NotCompleted;
                case ExceptionResource.Task_ThrowIfDisposed:
                    return SR.Task_ThrowIfDisposed;
                case ExceptionResource.Task_WaitMulti_NullTask:
                    return SR.Task_WaitMulti_NullTask;
                default:
                    Debug.Assert(false,
                        "The enum value is not defined, please check the ExceptionResource Enum.");
                    return "";
            }
        }
    }

    //
    // The convention for this enum is using the argument name as the enum name
    // 
    internal enum ExceptionArgument
    {
        obj,
        dictionary,
        array,
        info,
        key,
        text,
        values,
        value,
        startIndex,
        task,
        ch,
        s,
        input,
        ownedMemory,
        list,
        index,
        capacity,
        collection,
        item,
        converter,
        match,
        count,
        action,
        comparison,
        exceptions,
        exception,
        pointer,
        start,
        format,
        culture,
        comparer,
        comparable,
        source,
        state,
        length,
        comparisonType,
        manager,
        sourceBytesToCopy,
        callBack,
        creationOptions,
        function,
        scheduler,
        continuationAction,
        continuationFunction,
        tasks,
        asyncResult,
        beginMethod,
        endMethod,
        endFunction,
        cancellationToken,
        continuationOptions,
        delay,
        millisecondsDelay,
        millisecondsTimeout,
        stateMachine,
        timeout,
    }

    //
    // The convention for this enum is using the resource name as the enum name
    // 
    internal enum ExceptionResource
    {
        Argument_InvalidArgumentForComparison,
        ArgumentOutOfRange_Index,
        ArgumentOutOfRange_Count,
        Arg_ArrayPlusOffTooSmall,
        NotSupported_ReadOnlyCollection,
        Arg_RankMultiDimNotSupported,
        Arg_NonZeroLowerBound,
        ArgumentOutOfRange_ListInsert,
        ArgumentOutOfRange_NeedNonNegNum,
        ArgumentOutOfRange_SmallCapacity,
        Argument_InvalidOffLen,
        Argument_CannotExtractScalar,
        ArgumentOutOfRange_BiggerThanCollection,
        Serialization_MissingKeys,
        Serialization_NullKey,
        NotSupported_KeyCollectionSet,
        NotSupported_ValueCollectionSet,
        InvalidOperation_NullArray,
        TaskT_TransitionToFinal_AlreadyCompleted,
        TaskCompletionSourceT_TrySetException_NullException,
        TaskCompletionSourceT_TrySetException_NoExceptions,
        NotSupported_StringComparison,
        ConcurrentCollection_SyncRoot_NotSupported,
        Task_MultiTaskContinuation_NullTask,
        InvalidOperation_WrongAsyncResultOrEndCalledMultiple,
        Task_MultiTaskContinuation_EmptyTaskList,
        Task_Start_TaskCompleted,
        Task_Start_Promise,
        Task_Start_ContinuationTask,
        Task_Start_AlreadyStarted,
        Task_RunSynchronously_Continuation,
        Task_RunSynchronously_Promise,
        Task_RunSynchronously_TaskCompleted,
        Task_RunSynchronously_AlreadyStarted,
        AsyncMethodBuilder_InstanceNotInitialized,
        Task_ContinueWith_ESandLR,
        Task_ContinueWith_NotOnAnything,
        Task_Delay_InvalidDelay,
        Task_Delay_InvalidMillisecondsDelay,
        Task_Dispose_NotCompleted,
        Task_ThrowIfDisposed,
        Task_WaitMulti_NullTask,
    }
}