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

WiFiClient client;
long myChannelNumber = 2684748;
const char * myWriteAPIKey = "LQUWUY1SJ62WWR6Z";
char ssid[] = "Wokwi-GUEST";
char pass[] = "";

DHTesp Gayathri;
TempAndHumidity data;
const int trigger = 13;
const int echo = 12;

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!");

    Gayathri.setup(18, DHTesp::DHT22);
    pinMode(2, OUTPUT);
    pinMode(4, OUTPUT);
    pinMode(17, OUTPUT);
    pinMode(trigger, OUTPUT);
    pinMode(echo, INPUT);
}

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

void loop() {
    data = Gayathri.getTempAndHumidity();

    // Check for valid sensor readings
    if (data.temperature == 0 && data.humidity == 0) {
        Serial.println("Failed to read from DHT sensor!");
        return; // Skip this loop iteration
    }

    int distance = finding_distance();
    if (distance == -1) {
        Serial.println("Failed to read distance!");
    }

    if (data.temperature > 70 && data.humidity < 30 && distance < 200) {
        digitalWrite(2, HIGH);
        digitalWrite(4, LOW);
        digitalWrite(17, LOW);
        Serial.println("You are in danger");
    } 
    else if (data.temperature >= 30 && data.temperature <= 70 && 
             data.humidity >= 30 && data.humidity <= 70 && 
             distance <= 300 && distance >= 200) {
        digitalWrite(2, LOW);
        digitalWrite(4, HIGH);
        digitalWrite(17, LOW);
        Serial.println("You are unsafe");
    } 
    else if (data.temperature < 30 && data.humidity > 70 && distance > 300) {
        digitalWrite(2, LOW);
        digitalWrite(4, LOW);
        digitalWrite(17, HIGH);
        Serial.println("You are safe");
    } 
    else {
        digitalWrite(2, LOW);
        digitalWrite(4, LOW);
        digitalWrite(17, LOW);
    }

    Serial.print("Humidity: ");
    Serial.println(data.humidity);
    Serial.print("Temperature: ");
    Serial.println(data.temperature);
    Serial.print("Distance: ");
    
    Serial.println("-----------------");

    // Update ThingSpeak
    ThingSpeak.setField(1, distance);
    ThingSpeak.setField(2, data.temperature);
    ThingSpeak.setField(3, data.humidity);
    
    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); // Consider using millis() for a non-blocking delay
}