// Copyright (c) Microsoft Corporation. All rights reserved.

// Licensed under the MIT license.

using System;

namespace Microsoft.ClearScript.Util

{

internal ref struct ValueScope

{

private readonly Action exitAction;

private bool disposed;

public ValueScope(Action exitAction)

{

this.exitAction = exitAction;

disposed = false;

}

public void Dispose()

{

if (!disposed)

{

disposed = true;

exitAction?.Invoke();

}

}

}

internal ref struct ValueScope<TValue>

{

private readonly Action<TValue> exitAction;

private bool disposed;

public TValue Value { get; }

public ValueScope(TValue value, Action<TValue> exitAction)

{

this.exitAction = exitAction;

disposed = false;

Value = value;

}

public void Dispose()

{

if (!disposed)

{

disposed = true;

exitAction?.Invoke(Value);

}

}

}

internal static class ScopeFactory

{

public static ValueScope Create(Action enterAction, Action exitAction)

{

enterAction?.Invoke();

return new ValueScope(exitAction);

}

public static ValueScope Create<TArg>(Action<TArg> enterAction, Action exitAction, in TArg arg)

{

enterAction?.Invoke(arg);

return new ValueScope(exitAction);

}

public static ValueScope<TValue> Create<TValue>(Func<TValue> enterFunc, Action<TValue> exitAction)

{

var value = (enterFunc is not null) ? enterFunc() : default;

return new ValueScope<TValue>(value, exitAction);

}

public static ValueScope<TValue> Create<TArg, TValue>(Func<TArg, TValue> enterFunc, Action<TValue> exitAction, in TArg arg)

{

var value = (enterFunc is not null) ? enterFunc(arg) : default;

return new ValueScope<TValue>(value, exitAction);

}

}

}