#define CLK 13
#define DIN 11
#define CS  10
#define X_SEGMENTS   4
#define Y_SEGMENTS   2
#define NUM_SEGMENTS (X_SEGMENTS * Y_SEGMENTS)

// a framebuffer to hold the state of the entire matrix of LEDs
// laid out in raster order, with (0, 0) at the top-left
byte fb[8 * NUM_SEGMENTS];
int headx=0;
int heady=0;
int length=1;
bool up=false;
bool down=false;
bool right=false;
bool left=false;
int movesfromswitch=0;
int score=0;
int lastmove=-1;
  int foodx=random(32);
  int foody=random(16);

 
void shiftAll2(byte send_to_address, byte send_this_data)
{
  digitalWrite(CS, LOW);
  for (int i = 0; i < NUM_SEGMENTS; i++) {
    shiftOut(DIN, CLK, MSBFIRST, send_to_address);
    shiftOut(DIN, CLK, MSBFIRST, send_this_data);
  }
  digitalWrite(CS, HIGH);
}
 
void shiftAll(byte address,byte data)
{
    digitalWrite(CS, LOW);
  for (int i=7; i>=0; i--)
  {  
    digitalWrite(CLK, LOW);   // incepe o scriere sincronizata
    digitalWrite(DIN, address & (0x01 << i)); // cand i=7 scriu cel mai din stg bit din data...
    digitalWrite(CLK, HIGH);   // a terminat sincronismul
  }
  for (int i=7; i>=0; i--)
  {  
    digitalWrite(CLK, LOW);   // incepe o scriere sincronizata
    digitalWrite(DIN, data & (0x01 << i)); // cand i=7 scriu cel mai din stg bit din data...
    digitalWrite(CLK, HIGH);   // a terminat sincronismul
  }
  digitalWrite(CS, HIGH);

}
void setup() {
  Serial.begin(115200);
  pinMode(CLK, OUTPUT);
  pinMode(DIN, OUTPUT);
  pinMode(CS, OUTPUT);

 
  pinMode(4, INPUT);
  pinMode(5, INPUT);
    pinMode(6, INPUT);
  pinMode(7, INPUT);
 
  // Setup each MAX7219





  shiftAll(0x0f, 0x00); //display test register - test mode off
  shiftAll(0x0b, 0x07); //scan limit register - display digits 0 thru 7
  shiftAll(0x0c, 0x01); //shutdown register - normal operation
  shiftAll(0x0a, 0x0f); //intensity register - max brightness
  shiftAll(0x09, 0x00); //decode mode register - No decode
}
 
void show() {
  for (byte row = 0; row < 8; row++) {
    digitalWrite(CS, LOW);
    byte segment = NUM_SEGMENTS;
    while (segment--) {
      byte x = segment % X_SEGMENTS;
      byte y = (segment / X_SEGMENTS) * 8;
      byte addr = (row + y) * X_SEGMENTS;
 
      if (segment >= X_SEGMENTS) { // odd rows of segments
       shiftOut(DIN, CLK, MSBFIRST, 8 - row);
        shiftOut(DIN, CLK, LSBFIRST, fb[addr + x]);  

 }else { // even rows of segments

    shiftOut(DIN, CLK, MSBFIRST, 1 + row);
        shiftOut(DIN, CLK, MSBFIRST, fb[addr - x + X_SEGMENTS - 1]);
      }
    }
    digitalWrite(CS, HIGH);
  }
}

int moduloval(int headx){
    if(headx<0){
  headx+=32;
  }

  if(headx>31){
  headx=0;
  }
  return headx;

}
// functie care aprinde pixelul (x,y) unde (0,0) este in partea dreapta-jos a matricei de leduri
void setpixel(int x,int y){
  x=moduloval(x);
  y=moduloval(y);
  int pos=y*32+x;
  int pos2=pos%8;
  fb[pos/8]=(1<<(pos2));
    

}

 
void loop(){
    byte rightbtn = digitalRead(4);
  byte downbtn = digitalRead(5);
  byte leftbtn = digitalRead(6);
  byte upbtn = digitalRead(7);


  for(int i=0; i<64; i++) fb[i]=0;
  setpixel(foodx,foody);
  if((rightbtn==1 || leftbtn==1) && (!right && !left)){
    if(up==true){
      lastmove=7;
    }
    else if(down==true){
      lastmove=5;
    }
             if(rightbtn==1){
              right = true;
              
             }
             if(leftbtn==1)
             {
             left=true;
             }
      up=false;
      down=false;
      movesfromswitch=0;
  }
    if((upbtn==1 || downbtn==1) && (!up && !down)){
          if(right==true){
      lastmove=4;
    }
    else if(left==true){
      lastmove=6;
    }
             if(upbtn==1){
              up=true;
             }
             if(downbtn==1)
             {
             down=true;
             }
      right=false;
      left=false;
            movesfromswitch=0;
  }
 
  if(up){
              heady+=1;

   }
             if(down)
             {
             heady-=1;
             }
                   if(right){
              headx-=1;

              
             }
             if(left)
             {
             headx+=1;
             }
             
 // modulo dimensiunea matricei de leduri
  if(headx<0){
  headx+=32;
  }
  if(heady<0){
heady+=16;
  }
  if(headx>31){
  headx=0;
  }
  if(heady>15){
    heady=0;
  }


/* incercare esuata de a desena coada   
 for(int i=0;i<length;i++){
              if(i==0){
        setpixel(headx,heady);
        }
      if(i<movesfromswitch){
        if(right){
          setpixel(headx+i,heady);
        }
        else if(left){
          setpixel(headx-i,heady);
        }
        else if(up){
          setpixel(headx,heady-i);
        }
        else if(down){
          setpixel(headx,heady+i);
        }


      }
      else {
        if(lastmove==4){
                    setpixel(headx+i,heady);
        }
        else if(lastmove==6){
          setpixel(headx-i,heady);
        }
        else if(lastmove==7){
          setpixel(headx,heady-i);
        }
        else if(lastmove==5){
          setpixel(headx,heady+i);
        }

      }
    }*/
 // daca capul sarpelui este pe aceeasi pozitie ca mancarea, creste scor-ul si lungimea, si se generaza un nou food
  if(headx==foodx && heady==foody){
    score+=1;
    length+=1;
    foodx=random(32);
    foody=random(16);
  }
     setpixel(headx,heady);
  
 
  show();
}