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

WiFiClient client;
long myChannelNumber = 2724688;
const char * myWriteAPIKey = "Y1655SIEUI2VTS1R";
char ssid[] = "Wokwi-GUEST";
char pass[] = "";

// LDR and Distance setup
int ldrPin = 34; // LDR connected to pin 34 (ADC pin)
const int relayPin = 2; // Relay connected to pin 2
const int led1Pin = 25; // LED 1 connected to pin 25
const int led2Pin = 26; // LED 2 connected to pin 26
const int led3Pin = 27; // LED 3 connected to pin 27
int ldrValue = 0;
int threshold = 500; // LDR threshold for relay
const int triggerPin = 12; // Trigger pin for ultrasonic sensor
const int echoPin = 14;    // Echo pin for ultrasonic sensor

void setup() {
    Serial.begin(115200);
    Serial.println("Hello, ESP32!");

    ThingSpeak.begin(client);
    
    WiFi.mode(WIFI_STA);
    WiFi.begin(ssid, pass);

    // Attempt to connect to WiFi with a timeout
    unsigned long startAttemptTime = millis();
    while (WiFi.status() != WL_CONNECTED && millis() - startAttemptTime < 15000) {
        Serial.print("Attempting to connect");
        delay(500);
        Serial.print(".");
    }
    if (WiFi.status() != WL_CONNECTED) {
        Serial.println("\nFailed to connect to WiFi.");
        while (true); // Stop execution
    }
    Serial.println("\nConnected to WiFi!");

    pinMode(relayPin, OUTPUT);
    pinMode(ldrPin, INPUT);
    pinMode(led1Pin, OUTPUT);
    pinMode(led2Pin, OUTPUT);
    pinMode(led3Pin, OUTPUT);
    pinMode(triggerPin, OUTPUT);
    pinMode(echoPin, INPUT);
}

int finding_distance() {
    digitalWrite(triggerPin, HIGH);
    delay(10); // Short pulse
    digitalWrite(triggerPin, LOW);
    long duration = pulseIn(echoPin, HIGH, 30000); // Timeout after 30ms
    return (duration > 0) ? (duration * 0.034 / 2) : -1; 
}

void loop() {
    ldrValue = analogRead(ldrPin); // Read the LDR value
    int distance = finding_distance(); // Read the distance
    Serial.print("LDR Value: ");
    Serial.println(ldrValue);
    Serial.print("Distance: ");
    Serial.println(distance);

    // Control relay based on LDR value
    if (ldrValue < threshold) {
        digitalWrite(relayPin, HIGH); // Turn on relay
        Serial.println("Relay ON: Low Light Detected");
    } else {
        digitalWrite(relayPin, LOW);  // Turn off relay
        Serial.println("Relay OFF: Sufficient Light Detected");
    }

    // Control LEDs based on distance and luminance
    digitalWrite(led1Pin, LOW);
    digitalWrite(led2Pin, LOW);
    digitalWrite(led3Pin, LOW);
    int led1Status = 0, led2Status = 0, led3Status = 0;

    if (distance <= 100 && ldrValue >= 900) {
        digitalWrite(led1Pin, HIGH); // Turn on LED 1
        led1Status = 1; // LED 1 is ON
        Serial.println("LED 1 ON: Distance 100, Luminance 900");
    } 
    else if (distance <= 200 && ldrValue >= 500) {
        digitalWrite(led2Pin, HIGH); // Turn on LED 2
        led2Status = 1; // LED 2 is ON
        Serial.println("LED 2 ON: Distance 200, Luminance 500");
    } 
    else if (distance <= 350 && ldrValue <= 40) {
        digitalWrite(led3Pin, HIGH); // Turn on LED 3
        led3Status = 1; // LED 3 is ON
        Serial.println("LED 3 ON: Distance 350, Luminance 40");
    }

    // Update ThingSpeak
    ThingSpeak.setField(1, distance); // Distance
    ThingSpeak.setField(2, ldrValue); // LDR value
    ThingSpeak.setField(3, led1Status); // LED 1 status
    ThingSpeak.setField(4, led2Status); // LED 2 status
    ThingSpeak.setField(5, led3Status); // LED 3 status
    ThingSpeak.setField(6, digitalRead(relayPin)); // Relay status (0 or 1)

    int statusCode = ThingSpeak.writeFields(myChannelNumber, myWriteAPIKey);
    if (statusCode == 200) {
        Serial.println("Channel update successful.");
    } else {
        Serial.println("Problem Writing data. HTTP error code: " + String(statusCode));
    }

    delay(1000); // Update every second
}