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

#define SCREEN_WIDTH 128 // OLED display width, in pixels
#define SCREEN_HEIGHT 64 // OLED display height, in pixels
#define OLED_RESET     -1 // Reset pin # (or -1 if sharing Arduino reset pin)
#define SCREEN_ADDRESS 0x3C ///< See datasheet for Address; 0x3D for 128x64, 0x3C for 128x32
Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, OLED_RESET);

int hysteresis = 1;

unsigned int ampMeasurement = 0;
unsigned int voltMeasurement = 0;

int ampOffset = 0;
unsigned int ampGoal = 0;

unsigned int ampBaseSetting = 40;

unsigned int pwm = 0;


void setup()
{
   
  Serial.begin(115200);

 
    Serial.println("started generator controller");
    // SSD1306_SWITCHCAPVCC = generate display voltage from 3.3V internally
    // SSD1306_EXTERNALVCC for 5V power
  if(!display.begin(SSD1306_SWITCHCAPVCC, SCREEN_ADDRESS)) {
    Serial.println(F("SSD1306 allocation failed"));
    for(;;); // Don't proceed, loop forever
  }

}

void loop()
{ 
  //get measurements and user input
  ampMeasurement = map(analogRead(A0), 0, 1023, 0, 100);
  ampOffset = map(analogRead(A1), 0, 1023, -40, 40);
  voltMeasurement = map(analogRead(A2), 0, 1023, 20, 32);


  //control logic
  ampGoal = ampBaseSetting + ampOffset;
  if (ampMeasurement < ampGoal) {
    pwm = pwm +1;
  }
  else if (ampMeasurement > ampGoal) {
    pwm = pwm -1;
  }

  //display parameters
  display.clearDisplay();
  display.setTextSize(1);             // Normal 1:1 pixel scale
  display.setTextColor(SSD1306_WHITE);        // Draw white text
  display.setCursor(0,0);             // Start at top-left corner
  display.println("DisOtto Generator");

  display.setTextSize(2);
  display.setCursor(0,10);
  display.println(ampMeasurement);
  display.setCursor(80, 10);
  display.println("A");

  display.setCursor(0,30);
  display.println(voltMeasurement);
  display.setCursor(80, 30);
  display.println("V");

  display.setTextSize(1);
  display.setCursor(0,48);
  display.println(pwm);
  display.setCursor(0,56);
  display.println("Offset: ");
  display.setCursor(60,56);
  display.println(ampOffset);

  display.display();


/*
  lastMillis = millis();

  */
}