/*
MQTT-Schalter. Schält ein oder aus. 2021-12-22
Wenn über MQTT "ein" empfangen wird, schält das Relais an,
wenn "aus" empfangen wird, schält das Relais ab.
*/
// //////////////////////////////////////////////////
#include <ESP8266WiFi.h>
#include <PubSubClient.h> //MQTT-functionality
#include <EEPROM.h> //For serial to EEprom

///// anpassen /////////////////////////////////////////////////////
const char* Whoami = "MQTT-Schalter V.2021-12-22-a";
const short int Ausgang = 12; //Ausgangspin = D6
/////////////////////////////////////////////////////////////////////
const int PIN_LED = 2; // D4 on NodeMCU and WeMos. Controls the onboard LED.
WiFiClient espClient;
PubSubClient client(espClient);
char msg[50];//storage for MQTT-Message
String statusflag;//speichert den Befehl (an, aus)
long lastMsg = 0;
//======== variables for Serial Input ====
String ssid;
String pass;
String mqtt_broker;
String topic;
//String actorid;
String chipid;
char ssidbuffer[25];
char passbuffer[25];
char brokerbuffer[25];
char topicbuffer[25];
//char actoridbuffer[25];
char chipidbuffer[25];
 
// ***************************************************************
void setup()
{
  
  pinMode(PIN_LED, OUTPUT);      // Initialize the BUILTIN_LED pin as an output
  pinMode(Ausgang, OUTPUT);         // Relais-Pin als Ausgang anmelden
  //Relais ansteuern.
  statusflag="nop";
  pinMode(12, OUTPUT);//=D6=Relaistransistor
  //PIN aus
  digitalWrite(12, LOW);
  Serial.begin(115200);
  delay(5000);
  //......... Serial Input 
  Serial.println();
  Serial.println("----------------------------");
  Serial.println(Whoami);
  Serial.println("----------------------------");
  Serial.println("Press Enter to start Setup");
  unsigned long start=millis();
  //10s: wait for serial input of Wifi credencials
  while((start+10000)>millis()) {
    yield();
    if (Serial.available()) {
      Serial.read();
      Serial.read();
      setupmenu();//function
      connectWIFI();//function
      return;
    }
  }
  connectWIFI();
  //MQTT-Broker verbinden
  client.setServer(brokerbuffer, 1883);
  client.setCallback(callback); //dient dem Empfang von MQTT-Nachrichten
  digitalWrite(PIN_LED, HIGH);
}

//###############################
void reconnect() {
   while (!client.connected()) {
      Serial.println("Connecting MQTT-Broker...");
      //ssid.toCharArray(ssidbuffer,25);
      //chipid.toCharArray(chipid_buffer,25);
      //chipid_buffer=string2char(String chipid);
      if (!client.connect(chipidbuffer)) {
          Serial.print("failed, rc=");
          Serial.print(client.state());
          Serial.println(" retrying in 5 seconds");
          delay(5000);
      }
  }
  client.subscribe(topicbuffer);
  Serial.println("MQTT Connected. Waiting for MQTT-Messages...");
  Serial.println("----------------------------");
}

//##############################
void callback(char* topic, byte* payload, unsigned int length) {
    Serial.print("Received message [");
    Serial.print(topic);
    Serial.print("] ");
    char msg[length+1];
    for (int i = 0; i < length; i++) {
        Serial.print((char)payload[i]);
        msg[i] = (char)payload[i];
    }
    Serial.println(" ");
 
    msg[length] = '\0';
    //wenn "an" empfangen wird Relais anschalten
    if(strcmp(msg,"an")==0){
      //statusflag löschen
      statusflag="nop";
    //Relais an, LED an (0 = an)
        digitalWrite(Ausgang, HIGH);
        digitalWrite(PIN_LED, LOW);
        Serial.print("Relais einschalten \n");
    }
    //wenn "aus" empfangen wird Relais ausschalten
    if (strcmp(msg, "aus") == 0) {
        //Relais aus, LED aus (0 = an)
        digitalWrite(Ausgang, LOW);
        digitalWrite(PIN_LED, HIGH);
        Serial.print("Relais ausschalten \n");
    }
}


//############### Main loop
void loop()
{
 if (!client.connected()) {
        reconnect();
    }
    //Client.loop prüft, ob MQTT-Nachrichten eingehen
    client.loop();
}





//##################### Setupmenu
void setupmenu() {
  Serial.println("Enter Setup");
  //;;;;; SSID-Eingabe
  Serial.print("SSID: ");
  ssid=String("");
  while(true) {
    if (Serial.available()) {
      char c=Serial.read();
      Serial.write(c);
      if (c==13) {
        break;
      }
      else {
        ssid=String(ssid+c);
      }
    yield();
    }
  }
  Serial.println();
 //;;;;; Passworteingabe
 Serial.print("PASS: ") ;
  pass=String("");
  while(true) {
    if (Serial.available()) {
      char c=Serial.read();
      Serial.write(c);
      if (c==13) {
        break;
      }
      else {
        pass=String(pass+c);
      }
      yield();
    }
  }
  Serial.println();
  //;;;;;;;Broker ip
  Serial.print("MQTT-Broker-IP: ");
  mqtt_broker=String("");
  while(true) {
    if (Serial.available()) {
      char c=Serial.read();
      Serial.write(c);
      if (c==13) {
        break;
      }
      else {
        mqtt_broker=String(mqtt_broker+c);
      }
    yield();
    }
  }
  Serial.println();
  //;;;;;;;;Topic Eingabe
  Serial.print("Topic: ");
  topic=String("");
  while(true) {
    if (Serial.available()) {
      char c=Serial.read();
      Serial.write(c);
      if (c==13) {
        break;
      }
      else {
        topic=String(topic+c);
      }
    yield();
    }
  }
  Serial.println(); 
//;;;;;;;; Chipid
  Serial.print("ChipID: ");
  chipid=String("");
  while(true) {
    if (Serial.available()) {
      char c=Serial.read();
      Serial.write(c);
      if (c==13) {
        break;
      }
      else {
        chipid=String(chipid+c);
      }
    yield();
    }
  }
  Serial.println();
  //;;; Schreiben ins EEProm vorbereiten
  ssid.trim();
  pass.trim();
  mqtt_broker.trim();
  topic.trim();
  chipid.trim();
  writePROM();
  Serial.println("Saved to EEPROM");
}
//##########################
void connectWIFI() {
  readPROM();
  Serial.println("") ;
  Serial.print("Connecting ") ;
  Serial.println(ssid) ;
  //Serial.println(pass) ;
  ssid.toCharArray(ssidbuffer,25);
  pass.toCharArray(passbuffer,25);
  WiFi.begin(ssidbuffer,passbuffer );
  while (WiFi.status()!=WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }
  Serial.println("");
  Serial.print("Connected to ");
  Serial.println(ssid);
  Serial.print("IP address: ");
  Serial.println(WiFi.localIP());
};
//##########################
void readPROM() {
  EEPROM.begin(512);
  EEPROM.get(0,ssidbuffer);
  ssid=String(ssidbuffer);
  EEPROM.get(25,passbuffer);
  pass=String(passbuffer);
  EEPROM.get(50,brokerbuffer);
  mqtt_broker=String(brokerbuffer);
  EEPROM.get(75,topicbuffer);
  topic=String(topicbuffer);
  EEPROM.get(125,chipidbuffer);
  chipid=String(chipidbuffer);
  Serial.println("### read from EEPROM ###");
  Serial.println("SSID: "+ssid);
  Serial.println("Password: ******");
  Serial.println("MQTT-Broker-IP: "+mqtt_broker);
  Serial.println("Topic: "+topic);
  Serial.println("Chip-MQTT-unique-ID: "+chipid);
  Serial.println("###");
  EEPROM.commit();
  EEPROM.end();
};
//#############################
void writePROM() {
  EEPROM.begin(512);
  strncpy(ssidbuffer,ssid.c_str(),25);
  EEPROM.put(0,ssidbuffer);
  strncpy(passbuffer,pass.c_str(),25);
  EEPROM.put(25,passbuffer);
  strncpy(brokerbuffer,mqtt_broker.c_str(),25);
  EEPROM.put(50,brokerbuffer);
  strncpy(topicbuffer,topic.c_str(),25);
  EEPROM.put(75,topicbuffer);
  strncpy(chipidbuffer,chipid.c_str(),25);
  EEPROM.put(125,chipidbuffer);
  EEPROM.commit();
  EEPROM.end();
};