#include "MIDI.h"

/* File name: 'DrumTrigger.ino' versjon 0.01
 *  
 * Original code by Travis Thatcher, made for his CR-5000
 * https://github.com/TravisThatcher/MIDI_TO_TRIGGER_SYNC
 * Rewritten to work with 12 input Simmons SDS 7 by 
 * Hans R Lønningdal http://snw.lonningdal.no
 * 
 * Dependencies: MIDI Library for the Arduino 4.2 by Francois Best
 * http://arduinomidilib.fortyseveneffects.com/index.html
 * http://projectgus.github.io/hairless-midiserial/
 *
 * MIT License  https://opensource.org/licenses/MIT   
 */

boolean DEBUG = false;  // to turn off all debug print messages

MIDI_CREATE_DEFAULT_INSTANCE();  // Thank you Francois!

#define NUMTRIGS 12     // number of trigger outputs
#define START_STOP A0   // status 
#define OCTAVE 60       // MIDI note #60 = C5

// Enable to set variable trigger time, use 5k or 10k pot
//#define TRIGGER_TIME_POT A1 // variable trigger time
// Enable to set variable MIDI channel, use pot or switch with resistors
//#define MIDI_CHANNEL_POT A2 // variable midi channel

int midiChannel = 1;  // receiving MIDI channel, use MIDI_CHANNEL_OMNI for all, or config with potentiometer
int triggerTime = 3;  // Simmons says 2 milliseconds for SDS 7 Sequencer Trigger Input
int currentTime=0;

// Set these to whatever works for your circuit connections
int triggerPins[] = {2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13}; 
// Hold times for triggers
int triggerTimes[] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}; 
// Initialize all triggers to off
int triggerStates[] = {LOW, LOW, LOW, LOW, LOW, LOW, LOW, LOW, LOW, LOW, LOW, LOW};


void setup() {
  
  // Enable these to be able to select MIDI channel at boot
  //pinMode(MIDI_CHANNEL_POT, INPUT); 
  //delay(2); // stabilize input
  //midiChannel = map( analogRead(MIDI_CHANNEL_POT), 0, 1024, 1, 17 ); // return 1-16 
  
  MIDI.turnThruOff();
  if(!DEBUG){
    MIDI.begin(midiChannel);  // Activate midi 
  }else{
    Serial.begin(19200); // Othewise debug mode = no midi, allows for printing debug info to serial monitor
  }
  if(DEBUG){ Serial.println("hello!"); }  

  // setup output pins
  pinMode(START_STOP, OUTPUT);
  digitalWrite(START_STOP, LOW);
  
  // Enable to use variable trigger time
  //pinMode(TRIGGER_TIME_POT, INPUT) // variable trigger time
  
  pinMode(2, OUTPUT);
  digitalWrite(2, LOW);
  pinMode(3, OUTPUT);
  digitalWrite(3, LOW);
  pinMode(4, OUTPUT);
  digitalWrite(4, LOW);
  pinMode(5, OUTPUT);
  digitalWrite(5, LOW);
  pinMode(6, OUTPUT);
  digitalWrite(6, LOW);
  pinMode(7, OUTPUT);
  digitalWrite(7, LOW);
  pinMode(8, OUTPUT);
  digitalWrite(8, LOW);
  pinMode(9, OUTPUT);
  digitalWrite(9, LOW);
  pinMode(10, OUTPUT);
  digitalWrite(10, LOW);
  pinMode(11, OUTPUT);
  digitalWrite(11, LOW);
  pinMode(12, OUTPUT);
  digitalWrite(12, LOW);
  pinMode(13, OUTPUT);
  digitalWrite(13, LOW);  
  
  MIDI.setHandleStart(HandleStart);
  MIDI.setHandleStop(HandleStop);
  MIDI.setHandleContinue(HandleContinue);
  MIDI.setHandleNoteOn(HandleNoteOn);
}

void loop() {
  
  MIDI.read();
     
  currentTime = millis(); 
    
  // check out the trigger states
  for(int i=0; i<NUMTRIGS; i++){
    if(triggerStates[i]==HIGH){
      // Enable this to retrieve value (0-1023) from pot to set trigger time
      //triggerTime = analogRead(TRIGGER_TIME_POT); // variable trigger time
      if(currentTime - triggerTimes[i] > triggerTime){
        if(DEBUG){ Serial.println("turning off!"); }
        digitalWrite(triggerPins[i], LOW);
        triggerStates[i]=LOW; 
      }
    }
  }  
  
}

void HandleStart() {
  digitalWrite(START_STOP, HIGH);
}

void HandleContinue() {
  digitalWrite(START_STOP, HIGH);
}

void HandleStop() {
  digitalWrite(START_STOP, LOW);
}

void HandleNoteOn(byte channel, byte pitch, byte velocity){
  if(DEBUG){ Serial.println(pitch); }
  // triggers!
  for(int i=0; i<NUMTRIGS; i++){    
    if(pitch-OCTAVE==i){
      digitalWrite(triggerPins[i], HIGH);
      triggerStates[i] = HIGH;
      triggerTimes[i] = currentTime;   
    }
  }
}