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

#define SCREEN_WIDTH 128 // OLED display width, in pixels
#define SCREEN_HEIGHT 64 // OLED display height, in pixels

int inMin = 0;  // Countdown Minute
int inSec = 5; // Countdown Seconds
int cdTime = (inMin * 60) + inSec; // Countdown Seconds


// Declaration for an SSD1306 display connected to I2C (SDA, SCL pins)
#define OLED_RESET     4 // Reset pin # (or -1 if sharing Arduino reset pin)
Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, OLED_RESET);


void setup()
{
  Serial.begin(9600);
  // SSD1306_SWITCHCAPVCC = generate display voltage from 3.3V internally
  if(!display.begin(SSD1306_SWITCHCAPVCC, 0x3C)) { // Address 0x3D for 128x64
    Serial.println(F("SSD1306 allocation failed"));
    for(;;); // Don't proceed, loop forever
  }
 
  pinMode(3, OUTPUT);
}

void countDown(int inMin, int inSec, float inVolt)
{
    boolean RUN = true;
    int inPwm = inVolt / 9 * 255;
    while (RUN)
    {
      inSec = inSec - 1;
      delay(1000);
      if (inSec == -1)
      {
        inSec = 59;
        inMin = inMin - 1;
      }
      if (inMin == -1)
      {
        inMin = 59;
      }
        analogWrite(3, inPwm);
        Serial.println(inPwm);
        display.clearDisplay();
        display.setTextSize(1);             // Normal 1:1 pixel scale
        display.setTextColor(SSD1306_WHITE);        // Draw white text
        display.setCursor(0,7);
      if (inPwm != 0) {
        display.print(F("Power"));
        display.setTextSize(2);
        display.setCursor(36,0); 
        display.print(inVolt);
        display.print(F("V"));
      }
      else {
        display.print(F("Cooldown"));
        
      }
        display.drawFastHLine(0,19,61,SSD1306_WHITE);
        display.drawFastVLine(0,19,17,SSD1306_WHITE);
        display.setTextSize(2);             // Normal 1:1 pixel scale
        display.setTextColor(SSD1306_BLACK, SSD1306_WHITE); // Draw 'inverse' text
        display.setCursor(1,20);
      if (inMin == 0 && inSec == 0)
      {
      RUN = false;
      display.println("DONE ");
      delay(1000);
      }
      else {
        if (inMin <= 9)
        {
          display.print('0');
        }
        display.print(inMin);
        display.print(':');
        if (inSec <= 9)
        {
          display.print('0');
        }
        display.print(inSec);
    
      }
      display.display();

    }
}
void breakIn() {
  countDown(0,5,1.5);
  countDown(0,5,0);
  countDown(0,5,2.0);
  countDown(0,5,0);
  countDown(0,5,2.5);
  countDown(0,5,0);
  countDown(0,5,3.0);
  countDown(0,5,0);
  countDown(0,5,3.5);
  countDown(0,5,0);
  countDown(0,5,4.0);
  countDown(0,5,0);
  countDown(0,5,4.5);
  countDown(0,5,0);
  countDown(0,5,5.0);
  countDown(0,5,0);
  countDown(0,5,5.5);
  countDown(0,5,0);
  countDown(0,5,6.0);
}
void loop()
{
  breakIn();
}