/*
Midi controller made with an Arduino Mega connected to sensors like : buttons, Piezo and Joystick.
This code sends midi signals via the USB port in "serial format". You need to install Hairless-midiserial software on Mac or PC to translate that "serial" midi signal to your DAW (Digital Audio Workstation)
http://projectgus.github.io/hairless-midiserial/
For Windows users, you will also need to install Loopmidi
http://www.tobias-erichsen.de/software/loopmidi.html
This example code is in the public domain.
*/

// variables

byte NoteON = 144;         // NoteOn command ( cf. protocole midi) http://computermusicresource.com/MIDI.Commands.html
byte ControlChange = 176;  // Control Change command ( cf. protocole midi) http://computermusicresource.com/MIDI.Commands.html

int ButtonPin[] ={22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33}; // Buttons Pin numbers (for the Arduino Mega)
byte NbButtons = 12; // Number of Buttons
int ButtonState[] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}; // variable for reading the pushButton status
int PreviousButtonState[] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};  // Variable to reccord last button state
int FirstPitchButton = 36; // Lowest pitch of all the notes that can be played by the Buttons  36 => C2
int MajorKeyButton[] = {0, 2, 4, 5, 7, 9, 11, 12, 14, 16};// Number of semitones for each note of a major Key

int LedButtonPin[] = {34, 35, 36, 37, 38 ,39 ,40, 41, 42, 43, 44, 45};   // LED Pin numbers (for the Arduino Mega)
byte NbLeds = NbButtons; // Number of Leds

int PiezoPin[] = {A12, A13, A14, A15}; // Piezo Sensors Pin numbers (using Arduino Mega)
int NbPiezo = 4; // Number of Piezo sensors
int FirstPitchPiezo = 103; // Pitch of the lowest note played by the Piezos 103 => G8
int MajorKeyPiezo[] = {0, 2, 4, 5, 7, 9, 11, 12, 14, 16}; // Number of semitones for each note of a major Key
int ThresholdPiezo = 60; // Anything over fifty means we've hit a Piezo
int DelayPiezo = 150;  // Delay minimum between two knock on a piezo
int LedPiezoPin[] = {2, 3, 4, 5}; // Piezo's LED Pin numbers

int Joystick[] = {A8,A9,A10, A11}; // Joysticks Pin numbers
int NbJoystick = 2; // Number of Joysticks
int JoystickPin = 0; // Variable to record the Joystick current value
int JoystickValue[] = {0, 0, 0, 0}; // Joystick value mapped between 0 and 127 to be compatible with midi protocol
int PreviousJoystickValue[] = {0, 0, 0, 0}; // Variable to record the Joystick last value

// functions

//  This function send a MIDI message via the serial port to the Hairless-midiserial software
void MIDImessage(byte NoteOrCmd, byte Pitch, byte velocity)
    {
    Serial.write(NoteOrCmd);
    Serial.write(Pitch);
    Serial.write(velocity);
    }

// the setup function runs once when you press reset or power the board
void setup() {

//Serial.begin(31250); // 31250 bps rate if you communicate via a midi shield
  Serial.begin(9600);  // 9600 bps rate if you communicate  via USB port (serial)

// initialize digital pin i as an output for the Leds
  for (int i=0; i<NbLeds; i++) {
  pinMode(LedButtonPin[i], OUTPUT);}

// initialize digital pin i as an output for the Leds Piezo.
  for (int i=0; i<NbPiezo; i++) {
  pinMode(LedPiezoPin[i], OUTPUT);}

// initialize digital pin i as an input for the Buttons.
  for (int i=0; i<NbButtons; i++) {
  pinMode(ButtonPin[i], INPUT);}

} //end void setup()

void loop() {

// Buttons sensors part

  for (int i=0; i<NbButtons; i++){
    // Read the state of the pushButton value:
    ButtonState[i] = digitalRead(ButtonPin[i]);
    int PitchButton = FirstPitchButton+MajorKeyButton[i]; // Pitch of the note to play
    // Check if the pushButton is pressed. if it is, the ButtonState is HIGH:
    if(PreviousButtonState[i] != ButtonState[i]){
      if (ButtonState[i] == HIGH) {
         PreviousButtonState[i] = ButtonState[i]; // Backup the value of the button
        // turn LED on:
        digitalWrite(LedButtonPin[i], HIGH);
        // Play note from FirstPitchButton+MajorKeyButton[i]
        MIDImessage(NoteON,PitchButton, 127); // Send the corresponding midi message to the serial port
        }
        else {
          PreviousButtonState[i] = ButtonState[i];
          // turn LED off:
          digitalWrite(LedButtonPin[i], LOW);
          // Stop the note (note off)
           MIDImessage(NoteON,PitchButton, 0); // Send the corresponding midi message to the serial port
            }
   } else {digitalWrite(LedButtonPin[i], ButtonState[i]);};
 }; // End of Buttons sensors part

// Piezo sensors part

  for (int i=0; i<NbPiezo; i++) {
    int PitchPiezo = FirstPitchPiezo+MajorKeyPiezo[i];
    int PiezoVal = analogRead(PiezoPin[i]);
    if (PiezoVal>ThresholdPiezo){
      MIDImessage(NoteON, PitchPiezo, 127); // Play the midi note
      digitalWrite(LedPiezoPin[i], HIGH); // Turn on the led
      delay(DelayPiezo);
      MIDImessage(NoteON, PitchPiezo, 0); // Turn off the midi note
      digitalWrite(LedPiezoPin[i],LOW);
      }
  }; // End of Piezo sensors part

// Joysticks sensors part

for (int i=0; i<NbJoystick*2; i++){
  JoystickPin = analogRead(Joystick[i]);
  JoystickValue[i] = map(JoystickPin, 0, 1023, 5, 123); // the mapped value should be from 0 to 127 for true midi signal but the extreme often sound to agressive so I choose 5 to 123
  if(PreviousJoystickValue[i]!= JoystickValue[i]){// If the Joystick has been moved
      PreviousJoystickValue[i] = JoystickValue[i]; // Backup the value of the joystick
      MIDImessage(ControlChange, i, JoystickValue[i]); // Send the corresponding midi message to the serial port
    }
}; // End of Joysticks sensors part

} // End void loop()