#include <Wire.h>
#include <Adafruit_MPU6050.h>
#include <Adafruit_Sensor.h>
#include <WiFi.h>
#include <HTTPClient.h>
#include <math.h>

// ===============================
// MPU6050 CONFIGURATION
// ===============================

Adafruit_MPU6050 mpu;

#define SDA_PIN 21
#define SCL_PIN 19

// Movement threshold
#define MOVEMENT_THRESHOLD 2.0


// ===============================
// WIFI CONFIGURATION
// ===============================

const char* WIFI_SSID = "Wokwi-GUEST";
const char* WIFI_PASSWORD = "";


// ===============================
// THINGSPEAK CONFIGURATION
// ===============================

// Use a NEW ThingSpeak Write API Key
const char* THINGSPEAK_API_KEY = "OA8MD2Q44FM9VB2Z";


// ===============================
// SETUP
// ===============================

void setup() {

  Serial.begin(115200);

  Serial.println();
  Serial.println("================================");
  Serial.println("     COLLAR MONITORING STARTED");
  Serial.println("================================");

  // -------------------------------
  // Start I2C
  // -------------------------------

  Wire.begin(SDA_PIN, SCL_PIN);

  // -------------------------------
  // Start MPU6050
  // -------------------------------

  if (!mpu.begin()) {

    Serial.println("ERROR: MPU6050 NOT FOUND!");

    while (1) {
      delay(10);
    }
  }

  Serial.println("MPU6050 INITIALIZED");

  // -------------------------------
  // Configure MPU6050
  // -------------------------------

  mpu.setAccelerometerRange(MPU6050_RANGE_8_G);

  // -------------------------------
  // Connect to WiFi
  // -------------------------------

  WiFi.begin(WIFI_SSID, WIFI_PASSWORD);

  Serial.print("Connecting to WiFi");

  while (WiFi.status() != WL_CONNECTED) {

    delay(500);
    Serial.print(".");
  }

  Serial.println();
  Serial.println("WiFi Connected!");

  Serial.print("IP Address: ");
  Serial.println(WiFi.localIP());

  Serial.println("--------------------------------");
}


// ===============================
// MAIN LOOP
// ===============================

void loop() {

  // =================================
  // 1. READ MPU6050
  // =================================

  sensors_event_t acceleration;
  sensors_event_t gyro;
  sensors_event_t temperature;

  mpu.getEvent(
    &acceleration,
    &gyro,
    &temperature
  );


  // =================================
  // 2. CALCULATE MOVEMENT
  // =================================

  float magnitude = sqrt(
    acceleration.acceleration.x *
    acceleration.acceleration.x +

    acceleration.acceleration.y *
    acceleration.acceleration.y +

    acceleration.acceleration.z *
    acceleration.acceleration.z
  );

  // Remove approximately 1g of gravity
  float movement = fabs(magnitude - 9.81);


  // =================================
  // 3. DETERMINE MOVEMENT STATUS
  // =================================

  int movementStatus;
  String status;

  if (movement > MOVEMENT_THRESHOLD) {

    movementStatus = 1;
    status = "MOVEMENT_DETECTED";

  }
  else {

    movementStatus = 0;
    status = "MOVEMENT_NOT_DETECTED";
  }


  // =================================
  // 4. DISPLAY COLLAR DATA
  // =================================

  Serial.println();
  Serial.println("COLLAR DATA");

  Serial.print("Animal ID: ");
  Serial.println("COW001");

  Serial.print("Movement Value: ");
  Serial.print(movement, 2);
  Serial.println(" m/s^2");

  Serial.print("Movement Status: ");
  Serial.println(status);


  // =================================
  // 5. DISPLAY ANIMAL STATUS
  // =================================

  if (movementStatus == 1) {

    Serial.println("STATUS: ANIMAL MOVING");

  }
  else {

    Serial.println("STATUS: NO MOVEMENT");
  }


  // =================================
  // 6. CREATE DATA PACKET
  // =================================

  Serial.print("DATA PACKET: ");

  Serial.print("COW001");

  Serial.print(",MOVEMENT:");

  Serial.print(movement, 2);

  Serial.print(",STATUS:");

  Serial.println(status);


  // =================================
  // 7. SEND DATA TO THINGSPEAK
  // =================================

  if (WiFi.status() == WL_CONNECTED) {

    HTTPClient http;

    // CORRECT THINGSPEAK URL
    String url ="https://api.thingspeak.com/update?api_key=";

    // Add API key
    url += THINGSPEAK_API_KEY;

    // Field 3 = Movement
    url += "&field3=";
    url += String(movement, 2);

    // Field 4 = Movement Status
    // 0 = NOT DETECTED
    // 1 = DETECTED
    url += "&field4=";
    url += String(movementStatus);


    // -------------------------------
    // Display request information
    // -------------------------------

    Serial.println();
    Serial.println("Sending data to ThingSpeak...");

    // Do NOT print the complete URL
    // because it contains your API key.


    // -------------------------------
    // Send HTTP request
    // -------------------------------

    http.begin(url);

    int responseCode = http.GET();


    // -------------------------------
    // Display HTTP response
    // -------------------------------

    Serial.print("Cloud Response: ");
    Serial.println(responseCode);


    // -------------------------------
    // Read ThingSpeak response
    // -------------------------------

    String response = http.getString();

    Serial.print("ThingSpeak Response: ");
    Serial.println(response);


    // -------------------------------
    // Check whether successful
    // -------------------------------

    if (responseCode == 200) {

      Serial.println("COLLAR DATA SENT SUCCESSFULLY");

    }
    else {

      Serial.println("COLLAR DATA NOT SENT");

      Serial.print("HTTP ERROR CODE: ");
      Serial.println(responseCode);
    }


    // Close HTTP connection
    http.end();

  }
  else {

    Serial.println("WIFI DISCONNECTED");
  }


  // =================================
  // 8. WAIT BEFORE NEXT UPDATE
  // =================================

  Serial.println("--------------------------------");
  Serial.println("Next update in 2 seconds...");

  delay(2000);
}