#include <SPI.h>
#include <UIPEthernet.h>
#include <UIP_ATEM.h>
#include <RF24.h>
#include <nRF24L01.h>

//Ethernet
byte mac[] = {0xAA, 0xDD, 0xBB, 0x10, 0x01, 0x01};
IPAddress ip(192, 168, 0, 20);

//IP of the ATEM switcher
ATEM AtemSwitcher(IPAddress(192, 168, 0, 50), 56417);

//tally LEDs
const int tallyLED[] = {2,3};
const int tallyLEDlength = 2;
boolean tallyLEDstat[2];

//init NRF
RF24 radio (7, 8);
const uint16_t address = 0xADB5;
uint16_t datasend = 0;

//define min interval to send data
unsigned long currentTime = millis();
unsigned long previousTime = 0;
const long intervalTime = 1000;

void setup(){
   for (int i=0; i < tallyLEDlength; i++){
    pinMode(tallyLED[i], OUTPUT);
    digitalWrite(tallyLED[i], LOW);
  }

  //start Ethernet
  Ethernet.begin(mac,ip);

  //start Serial
  Serial.begin(9600);  

  //connect to the switcher
  AtemSwitcher.serialOutput(true);
  AtemSwitcher.connect();

  //start NRF
  radio.begin();
  radio.openWritingPipe(address);
  radio.setPALevel(RF24_PA_MIN);
  radio.setDataRate(RF24_1MBPS);
  //radio.disableDynamicPayloads();
  radio.setAutoAck(false);
  radio.disableCRC();
  radio.stopListening();

  delay(100);
}

void loop(){
  //check for new packages
  AtemSwitcher.runLoop();

  previousTime = currentTime;
  currentTime = millis();
  
  if (dataChanged() || currentTime - previousTime >= intervalTime)
    sendNRF();
}

void sendNRF(){
  for (int i=0; i < tallyLEDlength; i++) {
    datasend = (datasend << 1) + tallyLEDstat[i];
  }
  datasend = datasend << (8 - tallyLEDlength);
  datasend = (datasend << 8) + getChecksum(datasend & 0xFF);
  
  radio.writeFast(&datasend, sizeof(datasend));
}

boolean dataChanged(){
  boolean changed = false;
  for (int i=0; i < tallyLEDlength; i++){
    if (AtemSwitcher.getProgramTally(i+1) == tallyLEDstat[i]){
      tallyLEDstat[i] = AtemSwitcher.getProgramTally(i+1);
      digitalWrite(tallyLED[i], !AtemSwitcher.getProgramTally(i+1));
      changed = true;
    }
  }
  return changed;
}

uint8_t getChecksum(uint8_t data){
  uint8_t checksum = 0;
  for (int i=8; i<8; i++) checksum += (data >> i) & 1;
  return checksum;
}