/*
 * DHT-Sensor: 
 */
#include "DHT.h"

#define DHTPIN 2     // Digital pin connected to the DHT sensor
// Feather HUZZAH ESP8266 note: use pins 3, 4, 5, 12, 13 or 14 --
// Pin 15 can work but DHT must be disconnected during program upload.

// Uncomment whatever type you're using!
//#define DHTTYPE DHT11   // DHT 11
//#define DHTTYPE DHT22   // DHT 22  (AM2302), AM2321
#define DHTTYPE DHT21   // DHT 21 (AM2301)

// Connect pin 1 (on the left) of the sensor to +5V
// NOTE: If using a board with 3.3V logic like an Arduino Due connect pin 1
// to 3.3V instead of 5V!
// Connect pin 2 of the sensor to whatever your DHTPIN is
// Connect pin 3 (on the right) of the sensor to GROUND (if your sensor has 3 pins)
// Connect pin 4 (on the right) of the sensor to GROUND and leave the pin 3 EMPTY (if your sensor has 4 pins)
// Connect a 10K resistor from pin 2 (data) to pin 1 (power) of the sensor

// Initialize DHT sensor.
// Note that older versions of this library took an optional third parameter to
// tweak the timings for faster processors.  This parameter is no longer needed
// as the current DHT reading algorithm adjusts itself to work on faster procs.
DHT dht(DHTPIN, DHTTYPE);

/*
 *  TimeServer
 */
#include <time.h> 
char tmp[50];
char time_value[20];
time_t old_time;
int fail_counter = 0;
int total_counter = 0;

/*
 *  WiFi
 */
#include <ESP8266WiFi.h>
#include <Ticker.h>
#include <AsyncMqttClient.h>
#define WIFI_SSID "Network"
#define WIFI_PASSWORD "Password"



// MQTT Broker Server Settings:
#define MQTT_HOST IPAddress(192, 168, 1, 95)
#define MQTT_PORT 1888
#define MQTT_PUB_Humidity "ESP8266/Humidity"
#define MQTT_PUB_Temp "ESP8266/Temperature"
#define MQTT_PUB_LastUpdate "ESP8266/LastUpdate"
#define MQTT_PUB_Error "ESP8266/Errors"
#define MQTT_PUB_Messages "ESP8266/Messages"

AsyncMqttClient mqttClient;
Ticker mqttReconnectTimer;

WiFiEventHandler wifiConnectHandler;
WiFiEventHandler wifiDisconnectHandler;
Ticker wifiReconnectTimer;

void connectToWifi() {
  delay(10);
// We start by connecting to a WiFi network
  Serial.println();
  Serial.print("Connecting to ");
  Serial.println(WIFI_SSID);
  WiFi.begin(WIFI_SSID, WIFI_PASSWORD);
  int initcounter = 0;
  while (WiFi.status() != WL_CONNECTED)
   {
     initcounter = initcounter + 1; 
     delay(200);
     Serial.print(".");
     if (initcounter == 100)
     {
        Serial.print("Verbindungsabbruch");
        delay(200);
     }
   }
}

void onWifiConnect(const WiFiEventStationModeGotIP& event) {
  Serial.println("");
  Serial.println("WiFi connected");
  Serial.println("IP address: ");
  Serial.println(WiFi.localIP());
  
  connectToMqtt();
}

void onWifiDisconnect(const WiFiEventStationModeDisconnected& event) {
  Serial.println("Disconnected from Wi-Fi.");
  mqttReconnectTimer.detach(); // ensure we don't reconnect to MQTT while reconnecting to Wi-Fi
  wifiReconnectTimer.once(2, connectToWifi);
}

void connectToMqtt() {
  Serial.println("Connecting to MQTT...");
  mqttClient.connect();
}

void onMqttConnect(bool sessionPresent) {
  Serial.println("Connected to MQTT.");
  Serial.print("Session present: ");
  Serial.println(sessionPresent);
}

void onMqttDisconnect(AsyncMqttClientDisconnectReason reason) {
  Serial.println("Disconnected from MQTT.");

  if (WiFi.isConnected()) {
    mqttReconnectTimer.once(2, connectToMqtt);
  }
}

void onMqttPublish(uint16_t packetId) {
  Serial.print("Publish acknowledged.");
  Serial.print("  packetId: ");
  Serial.println(packetId);
}

void onMqttSubscribe(uint16_t packetId, uint8_t qos) {
  Serial.println("Subscribe acknowledged.");
  Serial.print("  packetId: ");
  Serial.println(packetId);
  Serial.print("  qos: ");
  Serial.println(qos);
}

void onMqttUnsubscribe(uint16_t packetId) {
  Serial.println("Unsubscribe acknowledged.");
  Serial.print("  packetId: ");
  Serial.println(packetId);
}

void Wifi_MQTT_Init(){
  wifiConnectHandler = WiFi.onStationModeGotIP(onWifiConnect);
  wifiDisconnectHandler = WiFi.onStationModeDisconnected(onWifiDisconnect);

  mqttClient.onConnect(onMqttConnect);
  mqttClient.onDisconnect(onMqttDisconnect);
  mqttClient.onPublish(onMqttPublish);
  mqttClient.setServer(MQTT_HOST, MQTT_PORT);
  mqttClient.onSubscribe(onMqttSubscribe);
  mqttClient.onUnsubscribe(onMqttUnsubscribe);
  mqttClient.onMessage(onMqttMessage);
    
  // If your broker requires authentication (username and password), set them below
  //mqttClient.setCredentials("REPlACE_WITH_YOUR_USER", "REPLACE_WITH_YOUR_PASSWORD");
  
  connectToWifi();

  }

void onMqttMessage(char* topic, char* payload, AsyncMqttClientMessageProperties properties, size_t len, size_t index, size_t total) {
  Serial.println("Publish received.");
  Serial.print("  topic: ");
  Serial.println(topic);
  Serial.print("  qos: ");
  Serial.println(properties.qos);
  Serial.print("  dup: ");
  Serial.println(properties.dup);
  Serial.print("  retain: ");
  Serial.println(properties.retain);
  Serial.print("  len: ");
  Serial.println(len);
  Serial.print("  index: ");
  Serial.println(index);
  Serial.print("  total: ");
  Serial.println(total);
  
  String messageTemp;
  for (int i = 0; i < total; i++) {
     Serial.print((char)payload[i]);
     messageTemp += (char)payload[i];
  }
  Serial.println();
  long Position = messageTemp.toInt();
  Serial.print("Nachricht: ");
  Serial.println(Position);
}

void setup() {
  Serial.begin(9600);
  Serial.println("");
  Serial.print("Modul wird hochgefahren.");
  Wifi_MQTT_Init();
  delay(100);
  dht.begin();
  delay(600);
  Serial.println("");

      time_t now = time(nullptr);
      now = now + 3600 + 3600;
      String time = String(ctime(&now));
      time.trim();
      time.substring(0,19).toCharArray(time_value, 20); 
      Serial.print("Uhrzeit: ");
      Serial.println(time);
      old_time = now;
  Serial.println("");
      
}

void DHT_Run() {
  // Reading temperature or humidity takes about 250 milliseconds!
  // Sensor readings may also be up to 2 seconds 'old' (its a very slow sensor)
  float h = dht.readHumidity();
  // Read temperature as Celsius (the default)
  float t = dht.readTemperature();

      time_t now = time(nullptr);
      now = now + 3600 + 3600;
      String time = String(ctime(&now));
      time.trim();
      time.substring(0,19).toCharArray(time_value, 20); 
      Serial.print("Uhrzeit: ");
      Serial.println(time);
 
 // Check if 1 hour is passed.
 if ((old_time + 3600) < now) {
    Serial.println("Time Reset.");
    old_time = now;
    fail_counter = 0;
    total_counter = 0;
   }
      

  // Check if any reads failed and exit early (to try again).
  total_counter = total_counter + 1;
  if (isnan(h) || isnan(t)) {
    fail_counter = fail_counter + 1;
    Serial.print(F("Failed to read from DHT sensor!  ("));
     Serial.print(String(total_counter));
     Serial.print("/");
     Serial.print(String(fail_counter));
     Serial.println(")");

      // Publish an MQTT error message on topic MQTT_PUB_Error
      uint16_t packetIdPub4 = mqttClient.publish(MQTT_PUB_Error, 1, true, String((fail_counter)).c_str()); delay(100);
      uint16_t packetIdPub5 = mqttClient.publish(MQTT_PUB_Messages, 1, true, String((total_counter)).c_str()); delay(100);
    return;
  }

  Serial.print(F("Humidity: "));
  Serial.print(h);
  Serial.print(F("%  Temperature: "));
  Serial.print(t);
  Serial.println(F("°C "));

        // Publish an MQTT message on topic MQTT_PUB_Humidity
      uint16_t packetIdPub1 = mqttClient.publish(MQTT_PUB_Humidity, 1, true, String(h).c_str()); delay(100);

      // Publish an MQTT message on topic MQTT_PUB_Temp
      uint16_t packetIdPub2 = mqttClient.publish(MQTT_PUB_Temp, 1, true, String(t).c_str()); delay(100);
      
      // Publish an MQTT message on topic LastUpdate
      uint16_t packetIdPub3 = mqttClient.publish(MQTT_PUB_LastUpdate, 1, true, time.c_str()); delay(100);

      // Publish an MQTT error message on topic MQTT_PUB_Error
      //uint16_t packetIdPub4 = mqttClient.publish(MQTT_PUB_Error, 1, true, String((fail_counter)).c_str()); delay(100);
      uint16_t packetIdPub5 = mqttClient.publish(MQTT_PUB_Messages, 1, true, String((total_counter)).c_str()); delay(100);
}

void loop() {
  delay(10000);
  DHT_Run();
  
}