//----------------------------------------------------------
// Simulation of a Eurorack Euclidean Sequencer 
// Based on the ideas of Hagiwo
// https://note.com/solder_state/n/n433b32ea6dbc
//
// Modified to have a different UX
// and additional AND output from output 1 and 2
//----------------------------------------------------------


//Encoder setting
//@ #define  ENCODER_OPTIMIZE_INTERRUPTS //countermeasure of encoder noise
//@ #include <Encoder.h>

//Oled setting
#include<Wire.h>
#include<Adafruit_GFX.h>
#include<Adafruit_SSD1306.h>

#define OLED_ADDRESS 0x3C
#define SCREEN_WIDTH 128
#define SCREEN_HEIGHT 64

#define ENCODER_CLK 2      // added for ky-040
#define ENCODER_DT  3      // added for ky-040

Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, 4);

//rotery encoder
//@ Encoder myEnc(2, 3);//use 3pin 2pin
//@ int oldPosition  = -999;
//@ int newPosition = -999;
int encodermove = 0;
int i = 0;

//push button
bool sw = 0;//push button
bool old_sw;//countermeasure of sw chattering
unsigned long sw_timer = 0;//countermeasure of sw chattering

//push button menu
bool sw2 = 0;//push button
bool old_sw2;//countermeasure of sw chattering
unsigned long sw_timer2 = 0;//countermeasure of sw chattering

//reset button
bool reset = 0;//reset input
bool old_reset;//countermeasure of reset chattering
unsigned long reset_timer = 0;//countermeasure of sw chattering

//each channel init param
byte hits[6] = { 3, 4, 5, 3, 2, 16};//each channel hits
byte offset[6] = { 0, 2, 1, 8, 3, 9};//each channele step offset
bool mute[6] = {0, 0, 0, 0, 0, 0}; //mute 0 = off , 1 = on
byte limit[6] = {16, 16, 16, 16, 16, 16};//each channel max step

//Sequence variable
byte j = 0;
byte k = 0;
byte m = 0;
byte buf_count = 0;

const static byte euc16[17][16] PROGMEM = {//euclidian rythm
 {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0},
 {1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0},
 {1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0},
 {1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0},
 {1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0},
 {1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 0},
 {1, 0, 0, 1, 0, 1, 0, 0, 1, 0, 0, 1, 0, 1, 0, 0},
 {1, 0, 0, 1, 0, 1, 0, 1, 0, 0, 1, 0, 1, 0, 1, 0},
 {1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0},
 {1, 0, 1, 1, 0, 1, 0, 1, 0, 1, 1, 0, 1, 0, 1, 0},
 {1, 0, 1, 1, 0, 1, 0, 1, 1, 0, 1, 1, 0, 1, 0, 1},
 {1, 0, 1, 1, 0, 1, 1, 0, 1, 1, 0, 1, 1, 0, 1, 1},
 {1, 0, 1, 1, 1, 0, 1, 1, 1, 0, 1, 1, 1, 0, 1, 1},
 {1, 0, 1, 1, 1, 1, 0, 1, 1, 1, 1, 0, 1, 1, 1, 1},
 {1, 0, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1},
 {1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0},
 {1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1}
};
bool offset_buf[6][16];//offset buffer , Stores the offset result

bool trg_in = 0;//external trigger in H=1,L=0
bool old_trg_in = 0;
byte playing_step[6] = {0, 0, 0, 0, 0, 0}; //playing step number , CH1,2,3,4,5,6
unsigned long gate_timer = 0;//countermeasure of sw chattering

//display param
byte select_menu = 1;//0=CH,1=HIT,2=OFFSET,3=LIMIT,4=MUTE,5=RESET,
byte select_ch = 0;//0~3 = each channel -1 , 4 = random mode
bool disp_reflesh = 1;//0=not reflesh display , 1= reflesh display , countermeasure of display reflesh bussy

const byte graph_x[6] = {8, 50, 92, 15, 55, 95};//each chanel display offset
const byte graph_y[6] = {2, 2,  2,  32, 32, 32};//each chanel display offset

byte line_xbuf[17];//Buffer for drawing lines
byte line_ybuf[17];//Buffer for drawing lines

const byte x16[16] = {15,  21, 26, 29, 30, 29, 26, 21, 15, 9,  4,  1,  0,  1,  4,  9};//Vertex coordinates
const byte y16[16] = {0,  1,  4,  9,  15, 21, 26, 29, 30, 29, 26, 21, 15, 9,  4,  1};//Vertex coordinates


//random assign
byte hit_occ[6] = {0, 10, 20, 20, 40, 80}; //random change rate of occurrence
byte off_occ[6] = {10, 20, 20, 30, 40, 20}; //random change rate of occurrence
byte mute_occ[6] = {20, 20, 20, 20, 20, 20}; //random change rate of occurrence
byte hit_rng_max[6] = {0, 14, 16, 8, 9, 16}; //random change range of max
byte hit_rng_min[6] = {0, 13, 6, 1, 5, 10}; //random change range of max

byte bar_now = 1;//count 16 steps, the bar will increase by 1.
byte bar_max[4] = {2, 4, 8, 16} ;//selectable bar
byte bar_select = 1;//selected bar
byte step_cnt = 0;//count 16 steps, the bar will increase by 1.

void setup() {
 Serial.begin(115200);    // added for ky-040

 // OLED setting
 display.begin(SSD1306_SWITCHCAPVCC, 0x3C);
 display.setTextSize(1);
 display.setTextColor(WHITE);
 OLED_display();

 //pin mode setting
 pinMode(ENCODER_CLK, INPUT);     // added for ky-040
 pinMode(ENCODER_DT, INPUT);      // added for ky-040

 pinMode(10, INPUT_PULLUP); //RESET
 pinMode(11, INPUT_PULLUP); //BUTTON2 MODE
 pinMode(12, INPUT_PULLUP); //BUTTON
 pinMode(5, OUTPUT); //CH1
 pinMode(6, OUTPUT); //CH2
 pinMode(7, OUTPUT); //CH3
 pinMode(8, OUTPUT); //CH4
 pinMode(9, OUTPUT); //CH5
 pinMode(10, OUTPUT); //CH6
}

int lastClk = HIGH;             // added for ky-040


void loop() {

 old_trg_in = trg_in;

//@ oldPosition = newPosition;
 //-----------------Rotery encoder read----------------------
//@ newPosition = myEnc.read();

//@ if ( newPosition   < oldPosition ) {//turn left
//@   oldPosition = newPosition;
//@       disp_reflesh = 1;//Enable while debugging.
//@   if (select_menu != 0) {
//@     select_menu --;
//@   }
//@ }
//@ else if ( newPosition    > oldPosition ) {//turn right
//@   oldPosition = newPosition;
//@   //    disp_reflesh = 1;//Enable while debugging.
//@   select_menu ++;
//@ }
//@ if (select_ch != 6) { // not random mode
 //@  select_menu = constrain(select_menu, 0, 5);
 //@}
 //@else  if (select_ch == 6) { // random mode
 //@  select_menu = constrain(select_menu, 0, 1);
 //@}

//-----------------Rotery encoder read----------------------
int newClk = digitalRead(ENCODER_CLK);    // added for ky-040
  if (newClk != lastClk) {
    // There was a change on the CLK pin
    lastClk = newClk;
    int dtValue = digitalRead(ENCODER_DT);
    if (newClk == LOW && dtValue == HIGH) {
      //Serial.println("Clockwise");
      //disp_reflesh = 1;//Enable while debugging.
      encodermove=1;   //some value for clockwise
    }
    if (newClk == LOW && dtValue == LOW) {
      //Serial.println("Anticlockwise");
      //disp_reflesh = 1;  //Enable while debugging.
      encodermove=2;    //some value for anticlockwise
    }
  }
 if (encodermove > 0) {
    //Serial.println(encodermove);
    
   switch (select_menu) {
     case 1: //hits
       if (select_ch != 3) { // not random mode
         if (encodermove == 1){
            hits[select_ch]++ ;
            if (hits[select_ch] >= 17) {
              hits[select_ch] = 0;
            }
            Serial.println(hits[select_ch]);
         }
         else if (encodermove == 2){
            if (hits[select_ch] > 0) {
              hits[select_ch]-- ;
            }
            Serial.println(hits[select_ch]);
         }
       }
       else  if (select_ch == 3) { // random mode
         bar_select ++;
         if (bar_select >= 4) {
           bar_select = 0;
         }
         
       }
       break;

     case 2: //offset
       if (encodermove == 1){
            offset[select_ch]++ ;
            if (offset[select_ch] >= 16) {
              offset[select_ch] = 0;
            }
       }
       else if (encodermove == 2){
            if (offset[select_ch] > 0) {
              offset[select_ch]--;
            }
       }
       break;

     case 3: //limit
       if (encodermove == 1){
            limit[select_ch]++ ;
            if (limit[select_ch] >= 17) {
                limit[select_ch] = 0;
            }
       }
       else if (encodermove == 2){
            if (limit[select_ch] > 0) {
                limit[select_ch]--;
            }
       }
       break;

     case 4: //mute
       mute[select_ch] = !mute[select_ch] ;
       break;

     case 5: //reset
       for (k = 0; k <= 2; k++) {
         playing_step[k] = 0;
       }
       break;
   }
   // end encoder move
   encodermove=0;      //reset encoderchange
 }
 
 
 //-----------------encoder push button - channel----------------------
 sw = 1;
 if ((digitalRead(12) == 0 ) && ( sw_timer + 300 <= millis() )) { //push button on ,Logic inversion , sw_timer is countermeasure of chattering
   sw_timer = millis();
   sw = 0;
       //disp_reflesh = 1;//Enable while debugging.
 }
 if (sw == 0) { //channel push button on
   select_menu ++;
   if (select_menu > 5) {   //roll over to first
         select_menu=1;
   }
   if (select_ch != 3) { // not random mode
       select_menu = constrain(select_menu, 0, 5);
    }
    else  if (select_ch == 3) { // random mode
       select_menu = constrain(select_menu, 0, 1);
    }
   
 }

 
 //-----------------push button - menu----------------------
 sw2 = 1;
 if ((digitalRead(11) == 0 ) && ( sw_timer2 + 300 <= millis() )) { //push button on ,Logic inversion , sw_timer is countermeasure of chattering
   sw_timer2 = millis();
   sw2 = 0;
       //disp_reflesh = 1;//Enable while debugging.
 }
 if (sw2 == 0) { //push button on
    select_ch ++;
       if (select_ch >= 4) {
         select_ch = 0;
    }
 }


 //-----------------reset button----------------------
 reset = 1;
 if ((digitalRead(10) == 0 ) && ( reset_timer + 300 <= millis() )) { //push button on ,Logic inversion , sw_timer is countermeasure of chattering
   reset_timer = millis();
   reset = 0;
       //disp_reflesh = 1;//Enable while debugging.
 }
 if (reset == 0) { //reset push button on
    for (k = 0; k <= 2; k++) {
         playing_step[k] = 0;
    }
    Serial.println("Reset");   
 }


 
 

 //-----------------offset setting----------------------
 for (k = 0; k <= 2; k++) { //k = 1~3ch
   for (i = offset[k]; i <= 15; i++) {
     offset_buf[k][i - offset[k]] = (pgm_read_byte(&(euc16[hits[k]][i]))) ;
   }

   for (i = 0; i < offset[k]; i++) {
     offset_buf[k][16 - offset[k] + i] = (pgm_read_byte(&(euc16[hits[k]][i])));
   }
 }

 //-----------------trigger detect & output----------------------
 trg_in = digitalRead(13);//external trigger in
 if (old_trg_in == 0 && trg_in == 1) {
   gate_timer = millis();
   for (i = 0; i <= 2; i++) {
     playing_step[i]++;      //When the trigger in, increment the step by 1.
     if (playing_step[i] >= limit[i]) {
       playing_step[i] = 0;  //When the step limit is reached, the step is set back to 0.
     }
   }
   for (k = 0; k <= 2; k++) {//output gate signal
     if (offset_buf[k][playing_step[k]] == 1 && mute[k] == 0) {
       switch (k) {
         case 0://CH1
           digitalWrite(5, HIGH);
           break;

         case 1://CH2
           digitalWrite(6, HIGH);
           break;

         case 2://CH3
           digitalWrite(7, HIGH);
           break;
       }
     }
     if (offset_buf[k][playing_step[k]] == 0 && mute[k] == 0) {
        switch (k) {
          case 0: //CH1
           digitalWrite(8, HIGH);   //inverted trigger from CH1
           break;
          case 1://CH2
           digitalWrite(9, HIGH);   //inverted trigger from CH2
          break;
        }  
      }
     
   }
   disp_reflesh = 1;//Updates the display where the trigger was entered.If it update it all the time, the response of gate on will be worse.

   if (select_ch == 3) {// random mode setting
     step_cnt ++;
     if (step_cnt >= 16) {
       bar_now ++;
       step_cnt = 0;
       if (bar_now > bar_max[bar_select]) {
         bar_now = 1;
         Random_change();
       }
     }
   }
 }

 if  (gate_timer + 10 <= millis()) { //off all gate , gate time is 10msec
   digitalWrite(5, LOW);
   digitalWrite(6, LOW);
   digitalWrite(7, LOW);
   digitalWrite(8, LOW);
   digitalWrite(9, LOW);
 }


 if (disp_reflesh == 1) {
   OLED_display();//reflesh display
   disp_reflesh = 0;
 }
}

void Random_change() { // when random mode and full of bar_now ,
 for (k = 1; k <= 2; k++) {

   if (hit_occ[k] >= random(1, 100)) { //hit random change
     hits[k] = random(hit_rng_min[k], hit_rng_max[k]);
   }

   if (off_occ[k] >= random(1, 100)) { //hit random change
     offset[k] = random(0, 16);
   }

   if (mute_occ[k] >= random(1, 100)) { //hit random change
     mute[k] = 1;
   }
   else if (mute_occ[k] < random(1, 100)) { //hit random change
     mute[k] = 0;
   }
 }
}

void OLED_display() {
 display.clearDisplay();
 //-------------------------menu display------------------
 //draw setting menu
  display.setCursor(19, 54);
 if (select_ch != 3) { // not random mode
   //display.setTextColor(BLACK, WHITE);
   //display.setTextSize(2);
   display.print(select_ch + 1);
 }
 else if (select_ch == 3) { //random mode
   display.print("R");
 }
 display.setCursor(36, 54);
 if (select_ch != 3) { // not random mode
   display.print("S");
 }
 else if (select_ch == 3) { //random mode
   display.print("O");
 }
 display.setCursor(48, 54);
 if (select_ch != 4) { // not random mode
   display.print("O");
   display.setCursor(60, 54);
   display.print("L");
   display.setCursor(72, 54);
   display.print("M");
   display.setCursor(84, 54);
   display.print("R");

   
 }

//-------------------------menu selected display------------------
 //random count square
 if (select_ch == 3) { //random mode
   //        display.drawRect(1, 32, 6, 32, WHITE);
   //    display.fillRect(1, 32, 6, 16, WHITE);
   display.drawRect(1, 62 - bar_max[bar_select] * 2, 6, bar_max[bar_select] * 2 + 2, WHITE);
   display.fillRect(1, 64 - bar_now * 2 , 6, bar_max[bar_select] * 2, WHITE);
 }
 //draw select triangle
 if ( select_menu == 0) {
   //display.drawTriangle(21, 45, 27, 45, 24, 51, WHITE);
   display.drawRect(20,52,9,11,WHITE);
 }
 else  if ( select_menu == 1) {
   //display.drawTriangle(35, 45, 41, 45, 38, 51, WHITE);
   display.drawRect(34,52,9,11,WHITE);
 }

 if (select_ch != 3) { // not random mode
   if ( select_menu == 2) {
     //display.drawTriangle(47, 45, 53, 45, 50, 51, WHITE);
     display.drawRect(46,52,9,11,WHITE);
   }
   else  if ( select_menu == 3) {
     //display.drawTriangle(59, 45, 65, 45, 62, 51, WHITE);
     display.drawRect(58,52,9,11,WHITE);
   }
   else  if ( select_menu == 4) {
     //display.drawTriangle(71, 45, 77, 45, 74, 51, WHITE);
     display.drawRect(70,52,9,11,WHITE);
   }
   else  if ( select_menu == 5) {
     //display.drawTriangle(83, 45, 89, 45, 86, 51, WHITE);
     display.drawRect(82,52,9,11,WHITE);
   }
 }


//-------------------------euclidean circle display------------------
 //draw step dot
 for (k = 0; k <= 2; k++) { //k = 1~6ch
   for (j = 0; j <= limit[k] - 1; j++) { // j = steps
     display.drawPixel(x16[j] + graph_x[k], y16[j] + graph_y[k], WHITE);
   }
 }

 //draw hits line : 2~16hits
 for (k = 0; k <= 2; k++) { //ch count
   buf_count = 0;
   for (m = 0; m < limit[k]; m++) {       //for (m = 0; m < 16 - 1; m++) {
     if (offset_buf[k][m] == 1) {
       line_xbuf[buf_count] = x16[m] + graph_x[k];//store active step
       line_ybuf[buf_count] = y16[m] + graph_y[k];
       buf_count++;
     }
   }
   
   for (j = 0; j < buf_count; j++) {    
     display.drawCircle(line_xbuf[j], line_ybuf[j], 2, WHITE);
          //display.drawLine(line_xbuf[j], line_ybuf[j], line_xbuf[j + 1], line_ybuf[j + 1], WHITE);
    }
   //display.drawCircle(line_xbuf[j], line_ybuf[j], 2, WHITE);
          //display.drawLine(line_xbuf[0], line_ybuf[0], line_xbuf[j], line_ybuf[j], WHITE);     
 }

 for (j = 0; j < 16; j++) {//line_buf reset
   line_xbuf[j] = 0;
   line_ybuf[j] = 0;
 }

 //draw hits line : 1hits
 //for (k = 0; k <= 2; k++) { //ch count
 //  buf_count = 0;
 //  if (hits[k] == 1) {
 //    //display.drawLine(15 + graph_x[k], 15 + graph_y[k], x16[offset[k]] + graph_x[k], y16[offset[k]] + graph_y[k], WHITE);
 //  }
 //}

 //draw play step circle
 for (k = 0; k <= 2; k++) { //ch count
   if (mute[k] == 0) { //mute on = no display circle
     if (offset_buf[k][playing_step[k]] == 1) {
       display.fillCircle(x16[playing_step[k]] + graph_x[k], y16[playing_step[k]] + graph_y[k], 3, WHITE);
     } else        //drawCircle
     //if (offset_buf[k][playing_step[k]] == 1) {
       display.fillCircle(x16[playing_step[k]] + graph_x[k], y16[playing_step[k]] + graph_y[k], 2, WHITE);
     //}
   }
 }
 display.display();
}