#include <ESP32Servo.h>
#include <WiFi.h>
#include "ThingSpeak.h"

const int myChannelNumber = 2623310;
const char* myApiKey = "LCVN9YA4INZMWAEZ";
const char* server = "api.thingspeak.com";

const char *ssid = "Wokwi-GUEST";
const char *pass = "";
WiFiClient client;

// Create servo objects
Servo azimuthServo;
Servo elevationServo;

// Define LDR pins
const int ldrPinTop = 32;
const int ldrPinBottom = 33;
const int ldrPinLeft = 34;
const int ldrPinRight = 35;

// Define servo pins
const int azimuthServoPin = 18;
const int elevationServoPin = 19;

// Solar panel simulation constants
const float PANEL_EFFICIENCY = 0.15; // 15% efficiency
const float PANEL_AREA = 0.01; // m^2
const float MAX_LIGHT_INTENSITY = 1000; // W/m^2, maximum possible light intensity
const float MAX_VOLTAGE = 18; // Volts, maximum possible voltage
const float MIN_VOLTAGE = 9; // Volts, minimum possible voltage

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

  // Attach servos to their respective pins
  azimuthServo.attach(azimuthServoPin);
  elevationServo.attach(elevationServoPin);

  // Initialize LDR pins as inputs
  pinMode(ldrPinTop, INPUT);
  pinMode(ldrPinBottom, INPUT);
  pinMode(ldrPinLeft, INPUT);
  pinMode(ldrPinRight, INPUT);

  WiFi.begin(ssid, pass);
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }
  Serial.println("\nWiFi connected");

  // Initialize ThingSpeak
  ThingSpeak.begin(client);
}

// Function to simulate voltage variation
float simulate_voltage(float lightIntensity) {
  // Voltage varies linearly with light intensity
  // Assume minimum voltage at 0 intensity, maximum at full intensity
  float voltage = MIN_VOLTAGE + (MAX_VOLTAGE - MIN_VOLTAGE) * (lightIntensity / MAX_LIGHT_INTENSITY);
  return voltage;
}

void loop() {
  // Read values from the LDRs
  int ldrValueTop = analogRead(ldrPinTop);
  int ldrValueBottom = analogRead(ldrPinBottom);
  int ldrValueLeft = analogRead(ldrPinLeft);
  int ldrValueRight = analogRead(ldrPinRight);

  // Print LDR values to Serial Monitor for debugging
  Serial.print("Top: "); Serial.print(ldrValueTop);
  Serial.print("  Bottom: "); Serial.print(ldrValueBottom);
  Serial.print("  Left: "); Serial.print(ldrValueLeft);
  Serial.print("  Right: "); Serial.println(ldrValueRight);

  // Get current servo positions
  int azimuthPos = azimuthServo.read();
  int elevationPos = elevationServo.read();

  // Determine which LDR reading to use based on servo positions
  float selectedLdrValue;

  if (elevationPos < 90) {
    // Panel facing more upwards, use Top or Bottom LDR
    selectedLdrValue = (ldrValueTop + ldrValueBottom) / 2.0;
  } else {
    // Panel facing more downwards, use Bottom LDR
    selectedLdrValue = (ldrValueBottom + ldrValueTop) / 2.0;
  }

  if (azimuthPos < 90) {
    // Panel facing more left, use Left LDR
    selectedLdrValue = (ldrValueLeft + ldrValueRight) / 2.0;
  } else {
    // Panel facing more right, use Right LDR
    selectedLdrValue = (ldrValueRight + ldrValueLeft) / 2.0;
  }

  // Calculate light intensity based on selected LDR value
  float lightIntensity = (selectedLdrValue / 4095.0) * MAX_LIGHT_INTENSITY;

  // Simulate variable voltage based on light intensity
  float voltage = simulate_voltage(lightIntensity);

  // Calculate solar panel output power
  float outputPower = PANEL_EFFICIENCY * PANEL_AREA * lightIntensity;

  // Calculate current from power and voltage
  float current = outputPower / voltage;

  // Send data to ThingSpeak
  ThingSpeak.setField(1, ldrValueTop);    // LDR Top value
  ThingSpeak.setField(2, ldrValueBottom); // LDR Bottom value
  ThingSpeak.setField(3, ldrValueLeft);   // LDR Left value
  ThingSpeak.setField(4, ldrValueRight);  // LDR Right value
  ThingSpeak.setField(5, lightIntensity); // Calculated light intensity
  ThingSpeak.setField(6, outputPower);    // Solar panel output power
  ThingSpeak.setField(7, current);        // Calculated current
  ThingSpeak.setField(8, voltage);        // Simulated voltage

  int status = ThingSpeak.writeFields(myChannelNumber, myApiKey);
  if (status == 200) {
    Serial.println("Data sent to ThingSpeak successfully!");
  } else {
    Serial.println("Error sending data to ThingSpeak");
  }

  // Calculate differences for servo movement
  int verticalDifference = ldrValueTop - ldrValueBottom;
  int horizontalDifference = ldrValueLeft - ldrValueRight;

  // Adjust azimuth (horizontal) servo position
  if (horizontalDifference > 100) {
    azimuthPos += 1; // Move servo to the right
  } else if (horizontalDifference < -100) {
    azimuthPos -= 1; // Move servo to the left
  }

  // Adjust elevation (vertical) servo position
  if (verticalDifference > 100) {
    elevationPos += 1; // Move servo up
  } else if (verticalDifference < -100) {
    elevationPos -= 1; // Move servo down
  }

  // Constrain servo positions to 0-180 degrees
  azimuthPos = constrain(azimuthPos, 0, 180);
  elevationPos = constrain(elevationPos, 0, 180);

  // Write the new positions to the servos
  azimuthServo.write(azimuthPos);
  elevationServo.write(elevationPos);

  delay(1000); // Wait a little before the next loop
}