//---------------------------------------------//
//    WWW.ARDUINORAILWAYCONTROL.COM            //
//---------------------------------------------//
//    app_layout_mega1.ino                     //
//    ARDUINO MEGA                             //
//    EX.1 ARDUINO RAILWAY LAYOUT CONTROL APP  //
//    PROTOCOL 2.5                             //
//    V.1.2021  Steve Massikker                //
//---------------------------------------------//

void(* resetFunc) (void) = 0;

#include <Servo.h>

// I/O PINS
#define JUNCTION_EN 5
#define KATO_A 6
#define KATO_B 7
#define PEM_A 8 // Point Electric Motor (PEM)
#define PEM_B 9
#define RELAY_IN1 10 // Relays for crossing
#define RELAY_IN2 11

Servo J1;

// VARIABLES
unsigned long millisJunction_switch_A, millisJunction_switch_B,
              millisJunction_switch_I, millisJunction_switch_J;  
bool stringComplete = false; 
String inputString = "";

bool switch_A = true, switch_B = true, switch_I = true, switch_J = true;
bool flag_change_junc = false;    


void setup() {

// Initializing COMM
  Serial.begin(9600); // Serial - USB
  Serial1.begin(9600); // RX - D19 | TX - D18
  inputString.reserve(4);

// Initializing PINs
  J1.attach(4); 
  pinMode(JUNCTION_EN, OUTPUT);
  pinMode(KATO_A, OUTPUT);
  pinMode(KATO_B, OUTPUT);  
  pinMode(PEM_A, OUTPUT);
  pinMode(PEM_B, OUTPUT);  
  pinMode(RELAY_IN1, OUTPUT);
  pinMode(RELAY_IN2, OUTPUT);    

// Set default directions for junctions
  J1.write(180);
  millisJunction_switch_A = millis();
  millisJunction_switch_B = millis();
  millisJunction_switch_I = millis();
  millisJunction_switch_J = millis();      
  digitalWrite(KATO_A, HIGH);
  digitalWrite(PEM_A, HIGH); 
  digitalWrite(RELAY_IN1, HIGH);
  digitalWrite(JUNCTION_EN, HIGH);

}

void loop() {
  
  // ----  START PARSING INCOMING APP COMMANDS
  if (stringComplete) {
    // RESET 
    if (inputString =="999z") resetFunc();
    // JUNCTIONS
    if (inputString.charAt(0) =='j') {
    	// App buttons
  		//1 2 3 4 5 6 7 8 9  Crossing  10 11 12 13 14 Three-way 15 16 17 DSS-1        DSS-2        18  
  		//A B C D E F G H I  J         K  L  M  N  O  P2 P3 P4  Q  R  S  T5 T6 T7 T8  U5 U6 U7 U8  V 

	  // Switch A
	  if (inputString.charAt(1) =='a') { // Branch direction
	    if (inputString.charAt(2) =='0') {
	      switch_A = false;
	      digitalWrite(PEM_A, LOW); // Unnecessary command - only to prevent opposite switching 
          digitalWrite(PEM_B, HIGH);
	    }
	    if (inputString.charAt(2) =='1') { // Throw direction
	      switch_A = true;
	      digitalWrite(PEM_B, LOW); // Unnecessary command - only to prevent opposite switching 
          digitalWrite(PEM_A, HIGH);
	    } 
	    millisJunction_switch_A = millis(); 
	  }

	  // Switch B
	  if (inputString.charAt(1) =='a') { // Branch direction
	    if (inputString.charAt(2) =='0') {
	      switch_B = false;
	      digitalWrite(KATO_A, LOW); // Unnecessary command - only to prevent opposite switching 
          digitalWrite(KATO_B, HIGH);
	    }
	    if (inputString.charAt(2) =='1') { // Throw direction
	      switch_B = true;
	      digitalWrite(KATO_B, LOW); // Unnecessary command - only to prevent opposite switching 
          digitalWrite(KATO_A, HIGH);
	    } 
	    millisJunction_switch_B = millis(); 
	  }

	  // Switch I - Servo
	  if (inputString.charAt(1) =='i') { 
	    if (inputString.charAt(2) =='0') {
	      switch_J = false;
          J1.write(0);
          delay(50);
          digitalWrite(JUNCTION_EN, HIGH);
	    }
	    if (inputString.charAt(2) =='1') {
	      switch_J = true;
          J1.write(180);
          delay(50);
          digitalWrite(JUNCTION_EN, HIGH);
	    }
	    millisJunction_switch_I = millis(); 
	  } 

	  // Switch J - Crossing
	  if (inputString.charAt(1) =='j') { 
	    if (inputString.charAt(2) =='0') {
	      switch_J = false;
	      digitalWrite(RELAY_IN1, LOW); // Unnecessary command - only to prevent opposite switching 
          digitalWrite(RELAY_IN2, HIGH);
	    }
	    if (inputString.charAt(2) =='1') {
	      switch_J = true;
	      digitalWrite(RELAY_IN2, LOW); // Unnecessary command - only to prevent opposite switching 
          digitalWrite(RELAY_IN1, HIGH);
	    } 
	    millisJunction_switch_J = millis(); 
	  }  

      flag_change_junc = false;
      
    }
    // LIGHTS
    if (inputString.charAt(0) =='l') {
       // Code for Lights control
    }
    // GEARS	
    if (inputString.charAt(0) =='g') {
       // Code for Gears control
    }	

    inputString = "";
    stringComplete = false;
  
  }

  // ----  MAIN LOGIC BLOCK
  if (flag_change_junc) {

     // Algorithm

    flag_change_junc = false;
  }

  // ---- AUTO-OFF

  if (millis() > (millisJunction_switch_A + 700)) {  // Delay 0.7s for Switch A
    digitalWrite(PEM_A, LOW); 
    digitalWrite(PEM_B, LOW);    
  }  

  if (millis() > (millisJunction_switch_B + 600)) {  // Delay 0.6s for Switch B
    digitalWrite(KATO_A, LOW); 
    digitalWrite(KATO_B, LOW);    
  }

  if (millis() > (millisJunction_switch_I + 800)) {  // Delay 0.8s for Switch I
    digitalWrite(JUNCTION_EN, LOW); 
  }

  if (millis() > (millisJunction_switch_J + 900)) {  // Delay 0.9s for Switch J
    digitalWrite(RELAY_IN1, LOW); 
    digitalWrite(RELAY_IN2, LOW);    
  }

  serial1Event();
}

//// FUNCTIONS ////
void serial1Event() {  // Commands from app
  if (Serial1.available()) {
    char inChar = (char)Serial1.read();
    inputString += inChar;
    if (inChar == 'z') {
      stringComplete = true;
    }
  }
}

void serialEvent() {
  if (Serial.available()) {
    char inChar = (char)Serial.read();
    inputString += inChar;
    if (inChar == 'z') {
      stringComplete = true;
    }
  }
}