#include <WiFi.h>
#include <Wire.h>
#include <LiquidCrystal_I2C.h>
#include "DHT.h"
#include <ArduinoJson.h>
#include <PubSubClient.h>

#define DHTPIN 15     // Digital pin connected to the DHT sensor
#define DHTTYPE DHT22 // DHT 22  (AM2302), AM2321
#define PIR 4
DHT dht(DHTPIN, DHTTYPE);
LiquidCrystal_I2C lcd(0x27, 22, 4); // set the LCD address to 0x27 for a 22 chars and 4 line display

int BUILTIN_LED = 32; // choose the pin for the LED
int inputPin = 12;    // choose the input pin (for PIR sensor)
int pirState = LOW;   // we start, assuming no motion detected
int val = 0;

int humid, temp;

const char *ssid = "Wokwi-GUEST";
const char *password = "";
const char *mqtt_server = "broker.mqtt-dashboard.com";

WiFiClient espClient;
PubSubClient client(espClient);
unsigned long lastMsg = 0;
#define MSG_BUFFER_SIZE (200) // Increase buffer size to handle larger JSON messages
char msg[MSG_BUFFER_SIZE];
int value = 0;

void setup()
{
    // Setup for serial communication
    Serial.begin(9600);

    lcd.init(); // Initialize the LCD
    lcd.backlight();
    lcd.setCursor(1, 0);
    lcd.print("ESP32 collecting data ...");
    delay(1000);

    dht.begin();

    pinMode(BUILTIN_LED, OUTPUT); // Initialize the BUILTIN_LED pin as an output

    setup_wifi();
    client.setServer(mqtt_server, 1883);
    client.setCallback(callback);
}

void loop()
{
    readData();

    if (!client.connected())
    {
        reconnect();
    }
    client.loop();

    unsigned long now = millis();
    if (now - lastMsg > 2000)
    {
        lastMsg = now;
        ++value;

        // Create JSON document
        DynamicJsonDocument doc(200);
        doc["message"] = "hello world";
        doc["humidity"] = humid;
        doc["temperature"] = temp;

        // Serialize JSON document to a char array
        serializeJson(doc, msg);

        Serial.print("Publish message: ");
        Serial.println(msg);

        // Publish the JSON message
        client.publish("outTopic", msg);
    }
}

void readData()
{
    // Wait a few seconds between measurements.
    delay(2000);

    // Reading temperature or humidity takes about 250 milliseconds!
    humid = dht.readHumidity();
    temp = dht.readTemperature();

    // Check if any reads failed and exit early (to try again).
    if (isnan(humid) || isnan(temp))
    {
        Serial.println(F("Failed to read from DHT sensor!"));
        return;
    }

    // Compute heat index in Celsius (isFahreheit = false)
    float hic = dht.computeHeatIndex(temp, humid, false);

    // Print to Screen
    lcd.clear();
    lcd.setCursor(0, 0);
    lcd.print("Humidity: ");
    lcd.print(humid);
    lcd.println("%");
    lcd.setCursor(0, 1);
    lcd.print("Temp: ");
    lcd.print(temp);
    lcd.println("C");
}

void setup_wifi()
{
    delay(10);
    Serial.println();
    Serial.print("Connecting to ");
    Serial.println(ssid);

    WiFi.mode(WIFI_STA);
    WiFi.begin(ssid, password);

    while (WiFi.status() != WL_CONNECTED)
    {
        delay(500);
        Serial.print(".");
    }

    randomSeed(micros());

    Serial.println("");
    Serial.println("WiFi connected");
    Serial.println("IP address: ");
    Serial.println(WiFi.localIP());
}

void callback(char *topic, byte *payload, unsigned int length)
{
    Serial.print("Message arrived [");
    Serial.print(topic);
    Serial.print("] ");
    for (int i = 0; i < length; i++)
    {
        Serial.print((char)payload[i]);
    }
    Serial.println();

    if ((char)payload[0] == '1')
    {
        digitalWrite(BUILTIN_LED, LOW);
        delay(1000);
    }
    else
    {
        digitalWrite(BUILTIN_LED, HIGH);
        delay(1000);
    }
}

void reconnect()
{
    while (!client.connected())
    {
        Serial.print("Attempting MQTT connection...");
        String clientId = "ESP8266Client-";
        clientId += String(random(0xffff), HEX);

        if (client.connect(clientId.c_str()))
        {
            Serial.println("connected");
            client.publish("outTopic", "hello everyone");
            client.subscribe("inTopic");
        }
        else
        {
            Serial.print("failed, rc=");
            Serial.print(client.state());
            Serial.println(" try again in 5 seconds");
            delay(5000);
        }
    }
}