//https://docs.turais.de/docs/modules/hw685/
//https://randomnerdtutorials.com/guide-for-oled-display-with-arduino/
//https://www.instructables.com/How-to-Display-Images-on-OLED-Using-Arduino/
#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
#define OLED_RESET     4 // 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);

// Define analog input Voltage
#define ANALOG_IN_PIN A2

// Floats for ADC voltage & Input voltage
float adc_voltage = 0.0;
float in_voltage = 0.0;

// Floats for resistor values in divider (in ohms)
float R1 = 30000.0;
float R2 = 7500.0;

// Float for Reference Voltage
float ref_voltage = 5.0;

// Integer for ADC value
int adc_value = 0;

//  //Define analog Input Current
// #define CurrentSensorPin  A2
// #define VREF 5000 // ADC's reference voltage on your Arduino,typical value:5000mV

// unsigned int voltage; //unit:mV
// float current;  //unit:mA

int analogPin = A3;
float read_curr_ma = 0.0;
float max_curr_ma = 20.0;
float min_curr_ma = 4.00;
float adc_intervals = 1023.0;

float max_voltac = 450.0;
float read_voltac = 0.0;

int max_ampereac = 20.0;
float read_ampereac = 0.0;
int read_temp = 0.0;

//Deklarasi rata- rata adc
const int numReadings = 10;

int readings[numReadings];  // pembacaan dari input analog
int readIndex = 0;          // indeks pembacaan saat ini
int total = 0;              // Total berjalan
int averageADC = 0;         // Rata- rata ADC



void setup()
{
  // Setup Serial Monitor
  Serial.begin(9600);
  // Serial.println("DC Voltage and Current Test");
  if (!display.begin(SSD1306_SWITCHCAPVCC, 0x3C)) { // Address 0x3D for 128x64
    Serial.println(F("SSD1306 allocation failed"));
    for (;;);
  }
  delay(1);
  display.clearDisplay();

  for (int thisReading = 0; thisReading < numReadings; thisReading++) {
    readings[thisReading] = 0;
  }
}

void loop() {

// Pengurangan pembacaan terakhir:
  total = total - readings[readIndex];
  // pembacaan sensor:
  readings[readIndex] = analogRead(analogPin);
  // tambahkan pembacaan sensor ke total:
  total = total + readings[readIndex];
  // selanjutnya di array atau masuk himpunan:
  readIndex = readIndex + 1;

  // jika berada diakhir himpunan..
  if (readIndex >= numReadings) {
    // ...diulang dari awal:
    readIndex = 0;
  }
  averageADC = total / numReadings;

  // Read the Analog Input Voltage
  adc_value = analogRead(ANALOG_IN_PIN);

  // Determine voltage at ADC input Voltage
  adc_voltage  = (adc_value * ref_voltage) / 1024.0;

  // Calculate voltage at divider input Voltage
  in_voltage = (adc_voltage / (R2 / (R1 + R2))+ 0.70) ;

  // Print results to Serial Monitor to 2 decimal places Voltage
  // Serial.print("Input Voltage =");
  // Serial.print(in_voltage, 2);
  // Serial.print("V  ");

  //read_curr_ma = (averageADC * (max_curr_ma / adc_intervals)+ 4.0);
  // Serial.print("Current:");
  // Serial.print(read_curr_ma);
  // Serial.println("mA");
  //read_curr_ma = (((max_curr_ma - min_curr_ma) / (adc_intervals - 0.0) * (averageADC - 0.0)) + 4.0);
  read_curr_ma = (((max_curr_ma - min_curr_ma) / (adc_intervals - 0.0)) * (averageADC - 0.0)) + min_curr_ma; // Adc to 4-20 mA 
  // */ (Nilai batas atas conversi - nilai batas bawah conversi)/ (nilai batas atas interval ADC - nilai batas bawah interval ) * (Nilai yang terbaca - nilai batas bawah interval) + nilai batas bawah conversi;

  //read_voltac = (averageADC * (max_voltac / adc_intervals)+0.0);
  // Serial.print("Vac:: ");
  // Serial.print(read_voltac);
  // Serial.println("V");
  //read_voltac = (((max_voltac - 0.0) / ( max_curr_ma - min_curr_ma)) * (read_curr_ma - min_curr_ma)) + 0.0; // 4-20 mA to 0-450 Vac
  
  read_temp = (((1200.0 - (-210)) / (max_curr_ma - min_curr_ma)) * (read_curr_ma - min_curr_ma)) + (-210); // 4-20 mA to -210 - 1200 °C
 // */ (Nilai batas atas conversi - nilai batas bawah conversi)/ (nilai batas atas arus mA - nilai batas bawah arus mA ) * (Nilai yang terbaca - nilai batas bawah arus mA) + nilai batas bawah conversi;

  read_ampereac = (averageADC * (max_ampereac / adc_intervals)+0.0);
  // Serial.print("Iac: ");
  // Serial.print(read_ampereac);
  // Serial.println(" A");

  // voltage = analogRead(CurrentSensorPin)/1024.0*VREF;
  // Serial.print("voltage:");
  // Serial.print(voltage);
  // Serial.print("mV  ");
  // current = voltage/120.0;  //Sense Resistor:120ohm
  // Serial.print("current:");
  // Serial.print(current);
  // Serial.println("mA");

  // display.setCursor(15, 0); //oled display judul
  // display.setTextSize(1);
  // display.setTextColor(WHITE);
  // display.print("0-10 V & 4-20 mA");

  display.setCursor(10, 10); //oled display judul 1
  display.setTextSize(1);
  display.setTextColor(WHITE);
  display.print(" Calibration Mater");

  // display.setCursor(0, 25); //oled display simbol voltage
  // display.setTextSize(2);
  // display.setTextColor(WHITE);
  // display.print("V: ");

  // display.setCursor(30, 25); //oled display satuan voltage
  // display.setTextSize(2);
  // display.setTextColor(WHITE);
  // display.print(in_voltage, 2);
  // display.println(" V");

  display.setCursor(0, 25); //oled display simbol voltage
  display.setTextSize(2);
  display.setTextColor(WHITE);
  display.print("T: ");

  display.setCursor(30, 25); //oled display satuan voltage
  display.setTextSize(2);
  display.setTextColor(WHITE);
  display.print(read_temp);
  display.println(" C");

  display.setCursor(0, 50); //oled display simbol arus
  display.setTextSize(2);
  display.setTextColor(WHITE);
  display.print("I: ");

  display.setCursor(30, 50); //oled display satuan arus
  display.setTextSize(2);
  display.setTextColor(WHITE);
  display.print(read_curr_ma, 2);
  display.println(" mA");

  display.display();
  delay(1);
  display.clearDisplay();
}