//PSI3542-2024 ATIVIDADE 5.1 THERMOSTAT

#include <WiFi.h>
#include <WiFiManager.h>          //https://github.com/tzapu/WiFiManager WiFi Configuration Magic
#include <PubSubClient.h>
#include "DHT.h"
#define DHTPIN 15
#define DHTTYPE DHT22   // DHT 22  (AM2302), AM2321

#define SECRET_MQTT_USERNAME "HCU0DhsCMxQYLQk7MgYGAwg"
#define SECRET_MQTT_CLIENT_ID "HCU0DhsCMxQYLQk7MgYGAwg"
#define SECRET_MQTT_PASSWORD "pBYVBwqYr4XMcVzW247qES40"

DHT dht(DHTPIN, DHTTYPE);

const char* mqtt_server = "mqtt3.thingspeak.com";

WiFiClient espClient;
PubSubClient client(espClient);
unsigned long lastMsg = 0;
#define MSG_BUFFER_SIZE  (50)
float temp = 0;
float hum = 0;
int value = 0;
float toffset;
float hist = 1;


void callback(char* topic, byte* payload, unsigned int length) {
  Serial.print("Message arrived topic=[");
  Serial.print(topic);
  Serial.print("] ");
  Serial.print("length=[");
  Serial.print(length);
  Serial.print("] ");
  Serial.print("payload=[");
  for (int i = 0; i < length; i++) {
    Serial.print((char)payload[i]);
  }
  Serial.println("] ");
  
  if (strcmp(topic, "channels/2658533/subscribe/fields/field3") == 0) {
    Serial.print("power=");
    Serial.println((char)payload[0]);

    // Switch on the LED if an 1 was received as first character
    if ((char)payload[0] == '1') {
      digitalWrite(2, LOW);   // Turn the LED on (Note that LOW is the voltage level
      // but actually the LED is on; this is because
      // it is active low on the ESP-01)
    } else {
      digitalWrite(2, HIGH);  // Turn the LED off by making the voltage HIGH
    }
  }
  else if (strcmp(topic, "channels/2658533/subscribe/fields/field4") == 0){

  toffset = atof((char *)payload);
  
  Serial.print("temperature offset=");
  Serial.println(toffset);
  }

}

void reconnect() {
//Loop until we're reconnected
  while (!client.connected()) {
    Serial.print("Attempting MQTT connection...");

    if (client.connect(SECRET_MQTT_CLIENT_ID, SECRET_MQTT_USERNAME, SECRET_MQTT_PASSWORD)) {
      Serial.println("Connected");
      // Once connected, publish an announcement...
      // ... and resubscribe
      client.subscribe("channels/2658533/subscribe/fields/field3");
      client.subscribe("channels/2658533/subscribe/fields/field4");
    } else {
      Serial.print("failed, rc=");
      Serial.print(client.state());
      Serial.println(" try again in 5 seconds");
      // Wait 5 seconds before retrying
      delay(5000);
    }
  }
}

void temperature_control(float t){

  if (t >= (toffset + hist)){
  digitalWrite(2, LOW);
  }
  else if(t <= (toffset - hist)){
  digitalWrite(2, HIGH);
  }

}

void setup() {
  pinMode(2, OUTPUT);     // Initialize the BUILTIN_LED pin as an output
  dht.begin();
  Serial.begin(115200);
  
  // ATIVIDADE 6
  //WiFiManager, Local intialization. Once its business is done, there is no need to keep it around
    WiFiManager wm;

    // reset settings - wipe stored credentials for testing
    // these are stored by the esp library
    // wm.resetSettings();

    // Automatically connect using saved credentials,
    // if connection fails, it starts an access point with the specified name ( "AutoConnectAP"),
    // if empty will auto generate SSID, if password is blank it will be anonymous AP (wm.autoConnect())
    // then goes into a blocking loop awaiting configuration and will return success result

    bool res;
    // res = wm.autoConnect(); // auto generated AP name from chipid
    // res = wm.autoConnect("AutoConnectAP"); // anonymous ap
    res = wm.autoConnect("AP-15471290","password"); // password protected ap

    if(!res) {
        Serial.println("Failed to connect");
        // ESP.restart();
    } 
    else {
        //if you get here you have connected to the WiFi    
        Serial.println("connected...yeey :)");
    }
  // FIM DA ATIVIDADE 6

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

void loop() {
  float temperature = dht.readTemperature();
  float humidity = dht.readHumidity();

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


  unsigned long now = millis();
  if (now - lastMsg > 10000) {
    lastMsg = now;
 
    String temp = String(temperature, 2);
    String hum = String(humidity, 1);

  // Prepare data string for ThingSpeak
  String data = "field1=" + temp + "&field2=" + hum + "&status=MQTTPUBLISH";

  Serial.println(data);

  char dataChar[100];
  data.toCharArray(dataChar, 100);

  client.publish("channels/2658533/publish", dataChar);

  temperature_control(temperature);

  }

  client.loop();
}