#include <WiFi.h>
#include <HTTPClient.h>
#include <Wire.h>
#include <Adafruit_MPU6050.h>
#include <Adafruit_Sensor.h>
#include <DallasTemperature.h>
#include <OneWire.h>
#include <TinyGPS++.h>

// WiFi credentials
const char* ssid = "Wokwi-GUEST";
const char* password = ""; // No password needed for Wokwi-GUEST

// ThingSpeak API
const char* server = "http://api.thingspeak.com/update";
String apiKey = "JATV72CSGLY2OCQE"; // Replace with your Write API Key

// Potentiometer (Pulse Sensor)
const int PulseWire = 36; // Use GPIO 36 (ADC1 channel 0)

// Accelerometer
Adafruit_MPU6050 mpu;

// Temperature Sensor
#define ONE_WIRE_BUS 4 // GPIO 4 for 1-Wire
OneWire oneWire(ONE_WIRE_BUS);
DallasTemperature sensors(&oneWire);

// GPS Module
// Use hardware serial port
HardwareSerial ss(2); // Serial2: RX = GPIO16, TX = GPIO17
TinyGPSPlus gps;

void setup() {
  Serial.begin(115200);
  ss.begin(9600, SERIAL_8N1, 16, 17); // Serial2 with RX = GPIO16, TX = GPIO17

  // Connect to WiFi
  connectToWiFi();

  // Initialize Accelerometer
  if (!mpu.begin()) {
    Serial.println("Failed to find MPU6050 chip");
    while (1) {
      delay(10);
    }
  }

  // Initialize Temperature Sensor
  sensors.begin();
}

void loop() {
  // Simulate GPS Data (fallback if GPS not available)
  float latitude = 37.7749;  // Example latitude
  float longitude = -122.4194;  // Example longitude

  // Read GPS Data
  while (ss.available() > 0) {
    gps.encode(ss.read());
  }

  if (gps.location.isUpdated()) {
    latitude = gps.location.lat();
    longitude = gps.location.lng();
  }

  // Read Potentiometer (Pulse Sensor) Data
  int potValue = analogRead(PulseWire);
  int myBPM = map(potValue, 0, 4095, 0, 150); // Map the potentiometer value to a BPM range

  // Read Accelerometer Data
  sensors_event_t a, g, temp;
  mpu.getEvent(&a, &g, &temp);

  // Read Temperature Data
  sensors.requestTemperatures();
  float temperatureC = sensors.getTempCByIndex(0);

  // Print data to Serial Monitor
  printSensorData(latitude, longitude, myBPM, temperatureC, a);

  // Send data to ThingSpeak
  if (WiFi.status() == WL_CONNECTED) {
    sendDataToThingSpeak(latitude, longitude, myBPM, temperatureC, a);
  } else {
    Serial.println("WiFi not connected, retrying...");
    connectToWiFi();
  }

  // Wait before sending the next set of data
  delay(20000);
}

void connectToWiFi() {
  Serial.println("Connecting to WiFi...");
  WiFi.begin(ssid, password);
  while (WiFi.status() != WL_CONNECTED) {
    delay(1000);
    Serial.print(".");
  }
  Serial.println("\nConnected to WiFi");
}

void printSensorData(float lat, float lon, int bpm, float tempC, sensors_event_t& accel) {
  Serial.print("Latitude= ");
  Serial.print(lat, 6);
  Serial.print(" Longitude= ");
  Serial.println(lon, 6);
  Serial.print("Heart Rate (BPM): ");
  Serial.println(bpm);
  Serial.print("Temperature (C): ");
  Serial.println(tempC);
  Serial.print("Accel X: ");
  Serial.print(accel.acceleration.x);
  Serial.print(" Accel Y: ");
  Serial.print(accel.acceleration.y);
  Serial.print(" Accel Z: ");
  Serial.println(accel.acceleration.z);
}

void sendDataToThingSpeak(float lat, float lon, int bpm, float tempC, sensors_event_t& accel) {
  HTTPClient http;
  String url = String(server) + "?api_key=" + apiKey +
               "&field1=" + String(lat, 6) +
               "&field2=" + String(lon, 6) +
               "&field3=" + String(bpm) +
               "&field4=" + String(tempC) +
               "&field5=" + String(accel.acceleration.x) +
               "&field6=" + String(accel.acceleration.y) +
               "&field7=" + String(accel.acceleration.z);
  http.begin(url);
  int httpCode = http.GET();
  if (httpCode > 0) {
    Serial.print("Data sent to ThingSpeak, HTTP response code: ");
    Serial.println(httpCode);
  } else {
    Serial.print("Error sending data to ThingSpeak, HTTP response code: ");
    Serial.println(httpCode);
  }
  http.end();
}