using System.Collections.Concurrent;

namespace SetAppVolumne
{
	static class Program
	{
		static void Main(string[] args)
		{
			//Console.WriteLine(MidiIn.DeviceInfo(0).ProductName);
			var x = new LDP();
		}
	}
	
	public class MidiEvent
	{
		public int controller;
		public float value;
		public DateTime time;
		
		public MidiEvent(int controller, float value) {
			this.controller = controller;
			this.value = getNormalizedValue(value);
			this.time = DateTime.Now.AddMilliseconds(8);
		}
		
		private float getNormalizedValue(float value)
		{
			// Max = 127
			float range = Math.Clamp(value, 5f, 120f) - 5f;
			float norm = range / 115.0f;
			return norm;
		}
	}

	public class LDP
	{
		[DllImport("user32.dll")]
		public static extern IntPtr GetWindowThreadProcessId(IntPtr hWnd, out uint ProcessId);

		[DllImport("user32.dll")]
		private static extern IntPtr GetForegroundWindow();

		Dictionary<int, string> lut = new Dictionary<int, string>()
		{
			{51, "System"},
			{52, "ActiveProcess"},
			{55, "foobar2000"},
			{57, "chrome"},
			{58, "Discord"}
		};

		ConcurrentDictionary<int, MidiEvent> event_list = new ConcurrentDictionary<int, SetAppVolumne.MidiEvent>();

		public LDP()
		{
			printProcessNames();
			
			var inmidi = new MidiIn(0);
			inmidi.MessageReceived += midiIn_messageReceive;

			inmidi.Start();
			
			while (true)
			{
				var now = DateTime.Now;
				foreach(var key in this.event_list.Keys)
				{
					var event_item = this.event_list[key];
					if (now >= event_item.time)
					{
						setVolumeForMatchingProcessNames(this.lut[event_item.controller], event_item.value);
						while (!this.event_list.TryRemove(key, out _)) {}
					}
				}
			}
		}

		private void midiIn_messageReceive(object sender, MidiInMessageEventArgs e)
		{
			var concrete_event = ((NAudio.Midi.ControlChangeEvent)e.MidiEvent);
			int controller = (int)concrete_event.Controller;
			if (!lut.ContainsKey(controller) && !lut.ContainsKey(controller - 40))
			{
				return;
			}
			
			if (controller > 90) 
			{
				setMuteForMatchingProcessNames(lut[controller - 40], concrete_event.ControllerValue > 0);
			}
			else
			{
				var pod_event = new MidiEvent(controller, concrete_event.ControllerValue);
				this.event_list[controller] = pod_event;
			}
		}

		private void setVolumeForMatchingProcessNames(string proc_name, float volume)
		{
			var x = new MMDeviceEnumerator();
			var device = x.GetDefaultAudioEndpoint(DataFlow.Render, Role.Multimedia);
			if (proc_name == "System")
			{
				device.AudioEndpointVolume.MasterVolumeLevelScalar = volume;
				return;
			}
			
			if (proc_name == "ActiveProcess")
			{
				uint active_process;
				GetWindowThreadProcessId(GetForegroundWindow(), out active_process);
				var proc_name_ = Process.GetProcessById((int)active_process).ProcessName;
				
				for (var i = 0; i < device.AudioSessionManager.Sessions.Count; i++)
				{
					var session = device.AudioSessionManager.Sessions[i];
					if (Process.GetProcessById((int)session.GetProcessID).ProcessName ==  proc_name_)
					{
						session.SimpleAudioVolume.Volume = volume;
					}
				}

				return;
			}
			
			for (var i = 0; i < device.AudioSessionManager.Sessions.Count; i++)
			{
				var session = device.AudioSessionManager.Sessions[i];
				var process = Process.GetProcessById((int)session.GetProcessID);
				if (process.ProcessName.Contains(proc_name))
				{
					session.SimpleAudioVolume.Volume = volume;
				}
			}
		}

		private void setMuteForMatchingProcessNames(string proc_name, bool mute)
		{
			var x = new MMDeviceEnumerator();
			var device = x.GetDefaultAudioEndpoint(DataFlow.Render, Role.Multimedia);
			if (proc_name == "System")
			{
				device.AudioEndpointVolume.Mute = mute;
				return;
			}

			if (proc_name == "ActiveProcess")
			{
				uint active_process;
				GetWindowThreadProcessId(GetForegroundWindow(), out active_process);
				var proc_name_ = Process.GetProcessById((int)active_process).ProcessName;

				for (var i = 0; i < device.AudioSessionManager.Sessions.Count; i++)
				{
					var session = device.AudioSessionManager.Sessions[i];
					if (Process.GetProcessById((int)session.GetProcessID).ProcessName == proc_name_)
					{
						session.SimpleAudioVolume.Mute = mute;
					}
				}

				return;
			}

			for (var i = 0; i < device.AudioSessionManager.Sessions.Count; i++)
			{
				var session = device.AudioSessionManager.Sessions[i];
				var process = Process.GetProcessById((int)session.GetProcessID);
				if (process.ProcessName.Contains(proc_name))
				{
					session.SimpleAudioVolume.Mute = mute;
				}
			}
		}

		private void printProcessNames()
		{
			var x = new MMDeviceEnumerator();
			var device = x.GetDefaultAudioEndpoint(DataFlow.Render, Role.Multimedia);

			for (var i = 0; i < device.AudioSessionManager.Sessions.Count; i++)
			{
				var session = device.AudioSessionManager.Sessions[i];
				var process = Process.GetProcessById((int)session.GetProcessID);
				Console.WriteLine(process.ProcessName);
			}
		}
	}
}