#include <Wire.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>
#include <driver/adc.h>
#include <esp_now.h>

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

Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, -1);

// Use an ADC1 channel connected GPIO pin for the thermistor
// Example: GPIO34 on ESP32 is ADC1_CHANNEL_6
#define ThermistorPin 34 // Update this to the actual GPIO pin number you're using
int Vo;
float R1 = 10000;
float logR2, R2, T, Tc;
float c1 = 1.009249522e-03, c2 = 2.378405444e-04, c3 = 2.019202697e-07;

void setup(){
  display.begin(SSD1306_SWITCHCAPVCC, 0x3C); // OLED address 
  display.clearDisplay();
  Serial.begin(9600);

  // Configure ADC resolution to 12 bits
  analogReadResolution(12);

  // Configure attenuation (if necessary)
  // For example, to measure up to the maximum range (approx. 3.3V), use 11dB attenuation
  analogSetPinAttenuation(ThermistorPin, ADC_ATTEN_DB_11);
}

void loop(){
  // For ESP32-C3, consider using analogReadMilliVolts for direct millivolt reading
  // This simplifies the calculation by providing a voltage reading directly
  Vo = analogRead(ThermistorPin);
  
  // Convert Vo to resistance (Ohm's Law) - adjust the calculation for 12-bit ADC
  R2 = R1 * (4095.0 / (float)Vo - 1.0);
  logR2 = log(R2);
  T = (1.0 / (c1 + c2 * logR2 + c3 * logR2 * logR2 * logR2));
  Tc = T - 273.15; // Convert Kelvin to Celsius
  
  display.clearDisplay();
  display.setTextSize(2);
  display.setTextColor(WHITE);
  display.setCursor(70, 0);
  display.println("C");
  display.display();
  display.setTextSize(2);
  display.setTextColor(WHITE);
  display.setCursor(3, 0);
  display.println(Tc, 2); // Print with 2 decimal places
  display.display();
  delay(1000); // Adjust delay as needed
}