using System;
using System.Runtime.InteropServices;

namespace ScreenConnect;

public class NativeMemoryMinder : CriticalFinalizerDisposableObject
{
	private bool zeroMemoryOnAllocate;

	public int Size { get; private set; }

	public IntPtr Address { get; private set; }

	public unsafe byte* ByteAddress => (byte*)(void*)Address;

	public unsafe int* IntAddress => (int*)(void*)Address;

	public NativeMemoryMinder(bool zeroMemoryOnAllocate = false, int initialSize = 0)
	{
		this.zeroMemoryOnAllocate = zeroMemoryOnAllocate;
		if (initialSize != 0)
		{
			EnsureSizePossiblyRelocating(initialSize);
		}
	}

	public unsafe void EnsureSizePossiblyRelocating(int minSize)
	{
		if (Size < minSize)
		{
			Address = ((Address == IntPtr.Zero) ? Marshal.AllocHGlobal(minSize) : Marshal.ReAllocHGlobal(Address, (IntPtr)minSize));
			if (zeroMemoryOnAllocate)
			{
				Extensions.ZeroMemory(ByteAddress + Size, minSize - Size);
			}
			Size = minSize;
		}
	}

	protected override void Dispose(bool disposing)
	{
		Marshal.FreeHGlobal(Address);
	}
}