using SFML.Graphics;
using SFML.Window;
using SFML.System;
using System.Diagnostics;
using FluidSim.Core;

namespace FluidSim;

public class Program
{
    private const int SampleRate = 44100;
    private static volatile bool running = true;

    public static void Main()
    {
        var mode = new VideoMode(new Vector2u(1280, 720));
        var window = new RenderWindow(mode, "Fluid Simulation");
        window.SetVerticalSyncEnabled(true);
        window.Closed += (_, _) => { running = false; window.Close(); };

        var soundEngine = new SoundEngine(bufferCapacity: 2048);
        soundEngine.Volume = 70;
        soundEngine.Start();

        double lastAudioTime = 0.0;
        var stopwatch = Stopwatch.StartNew();

        int warmupSamples = SampleRate / 2;
        float[] warmup = new float[warmupSamples];
        for (int i = 0; i < warmupSamples; i++)
            warmup[i] = 0;

        soundEngine.WriteSamples(warmup, warmupSamples);
        lastAudioTime = stopwatch.Elapsed.TotalSeconds;

        const int chunkSize = 2048;
        float[] buffer = new float[chunkSize];

        Simulation.Initialize(SampleRate);

        while (window.IsOpen)
        {
            window.DispatchEvents();

            double currentTime = stopwatch.Elapsed.TotalSeconds;
            double elapsed = currentTime - lastAudioTime;
            int samplesNeeded = (int)(elapsed * SampleRate);

            while (samplesNeeded > 0 && running)
            {
                int toGenerate = Math.Min(samplesNeeded, chunkSize);
                for (int i = 0; i < toGenerate; i++)
                {
                    buffer[i] = Simulation.Process();
                }
                soundEngine.WriteSamples(buffer, toGenerate);
                samplesNeeded -= toGenerate;
            }

            lastAudioTime = currentTime;

            window.Clear(Color.Black);
            window.Display();
        }

        soundEngine.Dispose();
        window.Dispose();
    }
}