viseq/src/midi.h

#pragma once

#include "libremidi/libremidi.hpp"
#include "libremidi/message.hpp"
#include "libremidi/observer_configuration.hpp"
#include "raylib.h"

#include <map>
#include <memory>
#include "datatypes.h"

struct NoteTimer{
	int midi_out;
	int channel;
	int note;
	int velocity;
	float start;
	int gate;
	bool erase = false;
};

class Midi {

	public:
		Midi() {
			int i = 0;
			for(const libremidi::output_port& port : obs.get_output_ports()){
				midi_out_ports.push_back({port, i, false});
				i++;
			}
		}

		libremidi::observer obs;

		std::map<int, std::shared_ptr<libremidi::midi_out>> midi_outs;
		std::vector<libremidi::input_port> midi_in_ports;
		std::vector<MidiOutPort> midi_out_ports;

		std::vector<NoteTimer> notes;

		float timer;
	
		void open_midi_out(MidiOutPort *out_port){
			if(!midi_outs.contains(out_port->number)){
				auto out = std::make_shared<libremidi::midi_out>();
				out->open_port(out_port->port);
				midi_outs[out_port->number] = out;
			}
		}

		void note(int midi_out, int channel, int note, int velocity, int gate){
			if(!midi_outs.empty()){
				if(midi_outs[midi_out]->is_port_open()){
					midi_outs[midi_out]->send_message(libremidi::channel_events::note_on(channel, note, velocity));
					notes.emplace_back(midi_out, channel, note, velocity, GetTime(), gate);
				}
			}
		}

		void update(){
			float time = GetTime();
			for(auto it = notes.begin(); it != notes.end(); ++it){
				if(time - it->start >= (float)it->gate / 1000.0f){
					midi_outs[it->midi_out]->send_message(libremidi::channel_events::note_off(it->channel, it->note, it->velocity));
					it->erase = true;
				}
			}
			std::erase_if(notes, [](const auto& item){return item.erase;});
			for(auto& p : midi_out_ports){
				if(p.enabled) {
					open_midi_out(&p);
				}
			}
		}
};