#include <Wire.h>
#include <WiFi.h>              
#include <Adafruit_GFX.h>      
#include <Adafruit_SSD1306.h>  
#include <DHTesp.h>
#include <PubSubClient.h>            
//  Christopher Rodriguez
#define SCREEN_WIDTH 128       
#define SCREEN_HEIGHT 64       
Adafruit_SSD1306 oled(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, -1); 


const int DHT_PIN = 15; 
DHTesp dht; 
const char* ssid = "Wokwi-GUEST"; /// wifi ssid clave del WIFI simulado 
const char* password = ""; 
const char* mqtt_server = "test.mosquitto.org";// mosquitto es el server url, si tiene duda ingrese desde el navegador

WiFiClient espClient; 
PubSubClient client(espClient); 
unsigned long lastMsg = 0; 
float temp = 0; 
float hum = 0;
int sensorPin = 26;            
DHTesp sensor;                 

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]); }}
void reconnect() {
while (!client. connected()) { 
  Serial.print("Attempting MQTT connection ... "); 
  String clientId = "ESP32Client-"; 
  clientId += String(random(0xffff), HEX); 
  if (client. connect(clientId.c_str())) { 
    Serial.println("Connected"); 
    client.publish("/ThinkIOT/Publish", "Welcome"); 
    client. subscribe("/ThinkIOT/Subscribe"); 
    } else {
      Serial.print("failed, rc="); 
      Serial.print(client.state()); 
      Serial.println(" try again in 5 seconds"); 
      delay(5000);
    }}
}

void setup( ) { 
  pinMode(2, OUTPUT); 
  Serial.begin(115200); 
  setup_wifi(); 
  client. setServer(mqtt_server, 1883); 
  client.setCallback(callback); 
  dht. setup(DHT_PIN, DHTesp:: DHT22);
    sensor.setup(sensorPin, DHTesp::DHT22);   
  Serial.begin(115200);                     
  oled.begin(SSD1306_SWITCHCAPVCC, 0x3C);  
  oled.clearDisplay();                      
  oled.setTextSize(2);                      
  oled.setTextColor(WHITE);                 
  oled.setCursor(0, 2);                     
  oled.display();                           
  delay(500); 
}

void loop() {
if (!client. connected()) { 
  reconnect(); 
  }
  client. loop();
  unsigned long now = millis(); 
  if (now - lastMsg > 2000) { //comando de publicación de datos 
  lastMsg = now;
  TempAndHumidity data = dht.getTempAndHumidity();
  String temp = String(data. temperature, 2);
  client.publish("/Thinkitive/temp", temp.c_str()); // publish temp topic /ThinkIOT/temp 
  String hum = String(data.humidity, 1); 
  client.publish("/Thinkitive/hum", hum.c_str()); // publish hum topic /ThinkIOT/hum
  
  Serial.print("Temperature: "); 
  Serial.println(temp); 
  Serial. print ("Humidity: ");
  Serial.println(hum);
  oled.clearDisplay();                      
  oled.setTextSize(2);                     
  oled.setTextColor(WHITE);                 
  oled.setCursor(0, 2);                     
  oled.print("TEMP=" + String(data.temperature, 1) + "C");  
  oled.setCursor(0, 36);                    
  oled.display();                           
  delay(2000);                              
  oled.clearDisplay();                      

  if (data.temperature <= 37) {           
    oled.setCursor(0, 27);               
    oled.println("TEMPERATURA NORMAL");    
    oled.display();                       
  }
  else {                                    
    oled.setCursor(0, 45);                  
    oled.println("TEMPERATURA ALTA");       
    oled.display();                         
  }

  delay(2000);                         
  oled.clearDisplay();
  }
}