using PerfectNumbers.Core;

namespace PerfectNumbers.Core.Gpu;

public static class GpuPrimeWorkLimiter
{
	private static readonly TimeSpan _pauseBetweenChecks = TimeSpan.FromSeconds(2);
	private static PollingSemaphore _semaphore = new(1, _pauseBetweenChecks);
	private static int _currentLimit = 1;

	public static void Acquire() => _semaphore.Wait();
	public static void Release() => _semaphore.Release();

	public static void SetLimit(int value)
    {
        if (value <= 0)
        {
            value = 1;
        }

        if (value == _currentLimit)
        {
            return;
	}

        // TODO: Switch to a shared limiter implementation with GpuWorkLimiter so we can coordinate CPU/GPU prime work using
        // the same semaphore pool without reallocating per adjustment.
        // var previous = _semaphore;
        _semaphore = new PollingSemaphore(value, _pauseBetweenChecks);
        _currentLimit = value;
        // previous.Dispose();
    }
}