#include <Wire.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>
#include <Keypad.h>

#define OLED_RESET 4
#define READ_PIN      A0
Adafruit_SSD1306 lcd(128, 64, &Wire, OLED_RESET);

double volts;
double bvolts;
double x, y;

bool Redraw1 = true;
bool Redraw2 = true;
bool Redraw3 = true;
bool Redraw4 = true;
double ox , oy ;


const byte ROWS = 4;
const byte COLS = 4;

char keys[ROWS][COLS] = {
  {'1', '2', '3', 'A'},
  {'4', '5', '6', 'B'},
  {'7', '8', '9', 'C'},
  {'*', '0', '#', 'D'}
};

char key;
byte rowPins[ROWS] = {13, 12, 11, 10};
byte colPins[COLS] = {9, 8, 7, 6};

Keypad keypad = Keypad(makeKeymap(keys), rowPins, colPins, ROWS, COLS);

const unsigned char Logo[] PROGMEM = {
  0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 
	0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 
	0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 
	0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 
	0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 
	0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 
	0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 
	0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 
	0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 
	0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 
	0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 
	0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 
	0xfd, 0xff, 0xff, 0xf8, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 
	0xfc, 0x00, 0x78, 0x00, 0x7f, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 
	0xfc, 0x00, 0x00, 0x00, 0x7f, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 
	0xf8, 0x00, 0x00, 0x00, 0x7f, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 
	0xf8, 0x00, 0x00, 0x00, 0x7f, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 
	0xf8, 0x00, 0x00, 0x00, 0x7f, 0x80, 0x07, 0xff, 0xfb, 0xf7, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 
	0xfc, 0x00, 0x00, 0x00, 0x7f, 0x00, 0x03, 0xff, 0xf1, 0xe3, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 
	0xff, 0xf0, 0x00, 0x00, 0xff, 0x00, 0x03, 0xff, 0xf0, 0xe1, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 
	0xff, 0xff, 0x03, 0xff, 0xff, 0x80, 0x0f, 0xff, 0xf0, 0xe1, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 
	0xff, 0xff, 0xc7, 0xff, 0xff, 0xf8, 0x7f, 0xff, 0xf0, 0xe1, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 
	0xff, 0xff, 0xff, 0xff, 0xff, 0xf8, 0xfe, 0x01, 0xf0, 0xe1, 0xe3, 0xe0, 0x1f, 0x80, 0x00, 0xff, 
	0xff, 0xff, 0xff, 0xff, 0xff, 0xf8, 0x7c, 0x00, 0xf0, 0xe1, 0xc1, 0xc0, 0x0f, 0x00, 0x00, 0x7f, 
	0xff, 0xff, 0xff, 0xff, 0xff, 0xf8, 0x78, 0x00, 0x70, 0xe1, 0x83, 0x80, 0x07, 0x00, 0x00, 0x3f, 
	0xff, 0xff, 0xff, 0xff, 0xff, 0xf8, 0x78, 0x78, 0x70, 0xe1, 0x87, 0x87, 0x87, 0x06, 0x08, 0x3f, 
	0xff, 0xff, 0xff, 0xff, 0xff, 0xf8, 0x78, 0xf8, 0x70, 0xe1, 0x0f, 0x87, 0x87, 0x0e, 0x1c, 0x3f, 
	0xff, 0xff, 0xff, 0xff, 0xff, 0xf8, 0x78, 0x78, 0x70, 0xe0, 0x1f, 0x87, 0x87, 0x0e, 0x1c, 0x3f, 
	0xff, 0xff, 0xff, 0xff, 0xff, 0xf8, 0x78, 0x00, 0xf0, 0xe0, 0x1f, 0x87, 0x87, 0x0e, 0x1c, 0x3f, 
	0xfc, 0x07, 0xff, 0xc0, 0xff, 0xf8, 0x78, 0x00, 0xf0, 0xe0, 0x1f, 0x87, 0x87, 0x0e, 0x1c, 0x3f, 
	0xfc, 0x07, 0xff, 0x80, 0xff, 0xf8, 0x78, 0x03, 0xf0, 0xe0, 0x0f, 0x87, 0x87, 0x0e, 0x1c, 0x3f, 
	0xfc, 0x07, 0xff, 0x80, 0xff, 0xf8, 0x78, 0x7f, 0xf0, 0xe1, 0x07, 0x87, 0x87, 0x0e, 0x1c, 0x3f, 
	0xfc, 0x07, 0xff, 0x80, 0xff, 0xf8, 0x78, 0x7f, 0xf0, 0xe1, 0x87, 0x87, 0x87, 0x0e, 0x1c, 0x3f, 
	0xfc, 0x07, 0xff, 0x80, 0xff, 0xf8, 0x78, 0x00, 0xf1, 0xe1, 0xc3, 0x80, 0x07, 0x0e, 0x1c, 0x3f, 
	0xfc, 0x07, 0xff, 0x80, 0xff, 0xf8, 0x78, 0x00, 0xf0, 0xe1, 0xc1, 0xc0, 0x0f, 0x0e, 0x1c, 0x3f, 
	0xfc, 0x07, 0xff, 0x80, 0xff, 0xf8, 0xfc, 0x00, 0xf1, 0xe3, 0xe1, 0xe0, 0x1f, 0x8f, 0x1c, 0x3f, 
	0xfc, 0x07, 0xff, 0x80, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 
	0xfc, 0x07, 0xff, 0x80, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 
	0xfc, 0x07, 0xff, 0x80, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 
	0xfc, 0x07, 0xff, 0x80, 0xff, 0xf9, 0xe7, 0xff, 0x1f, 0xff, 0xff, 0xff, 0xfe, 0xf3, 0xff, 0xff, 
	0xfc, 0x03, 0xff, 0x00, 0xff, 0xf9, 0xe7, 0xff, 0xbf, 0xff, 0xff, 0xff, 0xfe, 0xe3, 0xff, 0xff, 
	0xfe, 0x03, 0xff, 0x00, 0xff, 0xf9, 0xe7, 0x07, 0xbb, 0xfe, 0x1e, 0x0c, 0x0e, 0xe0, 0xef, 0x7f, 
	0xfe, 0x00, 0xfc, 0x01, 0xff, 0xf9, 0xe6, 0x03, 0x11, 0xcc, 0x0c, 0x08, 0x0c, 0xc0, 0xc7, 0x3f, 
	0xfe, 0x00, 0x30, 0x01, 0xff, 0xf9, 0xe6, 0x23, 0x11, 0xc8, 0xc4, 0x78, 0xfc, 0x73, 0xc7, 0x3f, 
	0xfe, 0x00, 0x00, 0x03, 0xff, 0xf9, 0xe6, 0x71, 0x19, 0xc8, 0xc4, 0x78, 0x7c, 0x73, 0xc7, 0x3f, 
	0xff, 0x00, 0x00, 0x03, 0xff, 0xf9, 0xe6, 0x71, 0x18, 0x98, 0x0c, 0x7c, 0x0c, 0x73, 0xc7, 0x3f, 
	0xff, 0x80, 0x00, 0x07, 0xff, 0xf9, 0xe6, 0x71, 0x1c, 0x18, 0x3c, 0x7e, 0x0c, 0x73, 0xc7, 0x3f, 
	0xff, 0xc0, 0x00, 0x0f, 0xff, 0xf9, 0xc6, 0x71, 0x1c, 0x18, 0xfc, 0x7f, 0xc4, 0x71, 0xc6, 0x3f, 
	0xff, 0xe0, 0x00, 0x1f, 0xff, 0xf8, 0x06, 0x71, 0x1c, 0x3c, 0x0c, 0x7c, 0x0c, 0xf0, 0x60, 0x3f, 
	0xff, 0xf8, 0x00, 0x3f, 0xff, 0xfc, 0x0f, 0x7b, 0xbe, 0x7e, 0x0e, 0xfc, 0x0e, 0xf8, 0x70, 0x3f, 
	0xff, 0xfc, 0x00, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xfc, 0x3f, 
	0xff, 0xff, 0x01, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xe0, 0x7f, 
	0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xf0, 0xff, 
	0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 
	0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 
	0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 
	0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 
	0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 
	0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 
	0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 
	0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 
	0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 
	0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 
	0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff
};

void setup() {
  lcd.begin(SSD1306_SWITCHCAPVCC, 0x3C);
  lcd.clearDisplay();
  lcd.drawBitmap(0, 0, Logo, 128, 64, WHITE);
  lcd.display();
  delay(3000);
	lcd.setTextSize(1);
  lcd.setTextColor(WHITE);
  lcd.setCursor(30,0);
  delay(1000);
  lcd.clearDisplay();
  
  pinMode(A0, INPUT);
}

unsigned long OldTime;
unsigned long counter;  

void loop() {
	
  bvolts = analogRead(A0);
  volts = (bvolts  / 204.6 ) ;

  DrawCGraph(lcd, x++, bvolts, 30, 50, 75, 30, 0, 100, 25, 0, 1024, 512, 0, "." , Redraw4);
    if (x > 100) {
    while (1) {
      
    }
    }
  delay(1000);


  key = keypad.getKey();
	
  lcd.setCursor(110,5);
  lcd.setTextSize(2);
  lcd.setTextColor(WHITE);
  lcd.print(key);
}

void DrawCGraph(Adafruit_SSD1306 &d, double x, double y, double gx, double gy, double w, double h, double xlo, double xhi, double xinc, double ylo, double yhi, double yinc, double dig, String title, boolean &Redraw) {

  double i;
  double temp;
  int rot, newrot;

  if (Redraw == true) {
    Redraw = false;
    d.fillRect(0, 0,  127 , 16, SSD1306_WHITE);
    d.setTextColor(SSD1306_BLACK, SSD1306_WHITE);
    d.setTextSize(1);
    d.setCursor(2, 4);
    d.println(title);
    ox = (x - xlo) * ( w) / (xhi - xlo) + gx;
    oy = (y - ylo) * (gy - h - gy) / (yhi - ylo) + gy;
    // draw y scale
    d.setTextSize(1);
    d.setTextColor(SSD1306_WHITE, SSD1306_BLACK);
    for ( i = ylo; i <= yhi; i += yinc) {
  
      temp =  (i - ylo) * (gy - h - gy) / (yhi - ylo) + gy;
      if (i == 0) {
        d.drawFastHLine(gx - 3, temp, w + 3, SSD1306_WHITE);
      }
      else {
        d.drawFastHLine(gx - 3, temp, 3, SSD1306_WHITE);
      }
      d.setCursor(gx - 27, temp - 3);
      d.println(i, dig);
    }


    for (i = xlo; i <= xhi; i += xinc) {

      d.setTextSize(1);
      d.setTextColor(SSD1306_WHITE, SSD1306_BLACK);
      temp =  (i - xlo) * ( w) / (xhi - xlo) + gx;
      if (i == 0) {
        d.drawFastVLine(temp, gy - h, h + 3, SSD1306_WHITE);
      }
      else {
        d.drawFastVLine(temp, gy, 3, SSD1306_WHITE);
      }
      d.setCursor(temp, gy + 6);
      d.println(i, dig);
    }
  }



  x =  (x - xlo) * ( w) / (xhi - xlo) + gx;
  y =  (y - ylo) * (gy - h - gy) / (yhi - ylo) + gy;
  d.drawLine(ox, oy, x, y, SSD1306_WHITE);
  d.drawLine(ox, oy - 1, x, y - 1, SSD1306_WHITE);
  ox = x;
  oy = y;

  d.display();

}