#include "BluetoothSerial.h"
#include "esp_bt_device.h"

BluetoothSerial SerialBT;

#define THERMISTOR_PIN 34   // ADC pin for MF52 thermistor

// Steinhart–Hart coefficients for MF52 thermistor (example, adjust for your thermistor)
#define SERIES_RESISTOR 10000
#define NOMINAL_RESISTANCE 10000
#define NOMINAL_TEMPERATURE 25
#define B_COEFFICIENT 3950

float readTemperature() {
  int adcValue = analogRead(THERMISTOR_PIN);
  float resistance = (4095.0 / adcValue - 1.0) * SERIES_RESISTOR;
  float steinhart;
  steinhart = resistance / NOMINAL_RESISTANCE;      // (R/Ro)
  steinhart = log(steinhart);                       // ln(R/Ro)
  steinhart /= B_COEFFICIENT;                       // 1/B * ln(R/Ro)
  steinhart += 1.0 / (NOMINAL_TEMPERATURE + 273.15);// + (1/To)
  steinhart = 1.0 / steinhart;                      // Invert
  steinhart -= 273.15;                              // convert to Celsius
  return steinhart;
}

void setup() {
  Serial.begin(115200);
  SerialBT.begin("FootLeft"); // Name of this ESP32
  Serial.println("Sender started. Waiting for receiver...");
}

void loop() {
  float tempLeft = readTemperature();
  Serial.printf("Left foot temp: %.2f °C\n", tempLeft);

  // Send temperature to receiver
  SerialBT.println(tempLeft);

  delay(2000); // send every 2 seconds
}