#include <Wire.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>
#include <Adafruit_Sensor.h>
#include <DHT.h>
#include <MAX30105.h>
#include "spo2_algorithm.h"
#include "heartRate.h"

// Display OLED
Adafruit_SSD1306 display(128, 64, &Wire, -1);

// DHT22
#define DHTPIN 15
#define DHTTYPE DHT22
DHT dht(DHTPIN, DHTTYPE);

// MAX30102
MAX30105 particleSensor;
uint32_t irBuffer[100]; // Infrared LED sensor data
uint32_t redBuffer[100]; // Red LED sensor data
int32_t bufferLength; // Data length
int32_t spo2; // SPO2 value
int8_t validSPO2; // Indicator to show if the SPO2 calculation is valid
int32_t heartRate; // Heart rate value calculated as per Maxim's algorithm
int8_t validHeartRate; // Indicator to show if the heart rate calculation is valid

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

  // Inicializar display OLED
  if (!display.begin(SSD1306_SWITCHCAPVCC, 0x3C)) {
    Serial.println(F("SSD1306 allocation failed"));
    for (;;);
  }
  display.display();
  delay(2000);
  display.clearDisplay();

  // Inicializar DHT22
  dht.begin();

  // Inicializar MAX30102
  if (!particleSensor.begin(Wire, I2C_SPEED_FAST)) {
    Serial.println(F("MAX30105 was not found. Please check wiring/power."));
    while (1);
  }
  byte ledBrightness = 50; // Options: 0=Off to 255=50mA
  byte sampleAverage = 4; // Options: 1, 2, 4, 8, 16, 32
  byte ledMode = 2; // Options: 1 = Red only, 2 = Red + IR, 3 = Red + IR + Green
  byte sampleRate = 100; // Options: 50, 100, 200, 400, 800, 1000, 1600, 3200
  int pulseWidth = 411; // Options: 69, 118, 215, 411
  int adcRange = 4096; // Options: 2048, 4096, 8192, 16384

  particleSensor.setup(ledBrightness, sampleAverage, ledMode, sampleRate, pulseWidth, adcRange);
}

void loop() {
  // Leer temperatura y humedad del DHT22
  float h = dht.readHumidity();
  float t = dht.readTemperature();

  // Leer datos del MAX30102
  bufferLength = 100; // Buffer length of 100 stores 4 seconds of samples running at 25sps
  for (byte i = 0; i < bufferLength; i++) {
    while (particleSensor.available() == false) { // Do we have new data?
      particleSensor.check(); // Check the sensor for new data
    }
    redBuffer[i] = particleSensor.getRed();
    irBuffer[i] = particleSensor.getIR();
    particleSensor.nextSample(); // We're finished with this sample so move to next sample
  }

  // Calcular frecuencia cardíaca y SpO2 después de los primeros 100 samples (primeros 4 segundos de muestras)
  maxim_heart_rate_and_oxygen_saturation(irBuffer, bufferLength, redBuffer, &spo2, &validSPO2, &heartRate, &validHeartRate);

  // Mostrar datos en el display OLED
  display.clearDisplay();
  display.setCursor(0, 0);
  display.setTextSize(1);
  display.setTextColor(WHITE);

  display.print("Temp: ");
  display.print(t);
  display.println(" *C");

  display.print("Humidity: ");
  display.print(h);
  display.println(" %");

  if (validHeartRate) {
    display.print("Heart Rate: ");
    display.print(heartRate);
    display.println(" bpm");
  } else {
    display.println("Invalid Heart Rate");
  }

  if (validSPO2) {
    display.print("SpO2: ");
    display.print(spo2);
    display.println(" %");
  } else {
    display.println("Invalid SpO2");
  }

  display.display();
  delay(2000); // Espera 2 segundos entre actualizaciones
}