#include <RFM69.h>
#include <SPI.h>
#include <SPIFlash.h>

#define NODEID      99
#define NETWORKID   100
#define GATEWAYID   1
#define FREQUENCY   RF69_915MHZ //Match this with the version of your Moteino! (others: RF69_433MHZ, RF69_868MHZ)
#define KEY         "thisIsEncryptKey" //has to be same 16 characters/bytes on all nodes, not more not less!
#define LED         9
#define SERIAL_BAUD 115200
#define ACK_TIME    30  // # of ms to wait for an ack

int TRANSMITPERIOD = 300; //transmit a packet to gateway so often (in ms)
byte sendSize=0;
boolean requestACK = false;
SPIFlash flash(8, 0xEF30); //EF40 for 16mbit windbond chip
RFM69 radio;

    // analog pin used to connect the potentiometer
 int potpin0 = 0;  

 typedef struct 
 {		
   int           Pot_0;                                   //store this potentiometer 0
 } Payload;
 Payload theData;

void setup() 
{
  Serial.begin(SERIAL_BAUD);
  radio.initialize(FREQUENCY,NODEID,NETWORKID);
  radio.setHighPower(); //uncomment only for RFM69HW!
  radio.encrypt(KEY);
  char buff[50];
  sprintf(buff, "\nTransmitting at %d Mhz...", FREQUENCY==RF69_433MHZ ? 433 : FREQUENCY==RF69_868MHZ ? 868 : 915);
  Serial.println(buff);
  
  if (flash.initialize())
    Serial.println("SPI Flash Init OK!");
  else
    Serial.println("SPI Flash Init FAIL! (is chip present?)");
}

long lastPeriod = -1;

void loop() 
{

  //process any serial input
  if (Serial.available() > 0)
  {
    char input = Serial.read();
    if (input >= 48 && input <= 57) //[0,9]
    {
      TRANSMITPERIOD = 100 * (input-48);
      if (TRANSMITPERIOD == 0) TRANSMITPERIOD = 1000;
      Serial.print("\nChanging delay to ");
      Serial.print(TRANSMITPERIOD);
      Serial.println("ms\n");
    }

  }

  //check for any received packets
  if (radio.receiveDone())
  {
    Serial.print('[');Serial.print(radio.SENDERID, DEC);Serial.print("] ");
    for (byte i = 0; i < radio.DATALEN; i++)
      Serial.print((char)radio.DATA[i]);
    Serial.print("   [RX_RSSI:");Serial.print(radio.readRSSI());Serial.print("]");

    if (radio.ACK_REQUESTED)
    {
      radio.sendACK();
      Serial.print(" - ACK sent");
      delay(10);
    }

    Serial.println();
  }
  
  int currPeriod = millis()/TRANSMITPERIOD;
  if (currPeriod != lastPeriod)
  {
         //fill in the struct with new values
    theData.Pot_0 = analogRead(potpin0);
       
    Serial.print("Sending struct (");
    Serial.print(sizeof(theData));
    Serial.print(" bytes) ... ");
    if (radio.sendWithRetry(GATEWAYID, (const void*)(&theData), sizeof(theData)))
      Serial.print(" ok!");
    else Serial.print(" nothing...");
    Serial.println();
    Blink(LED,3);
    lastPeriod=currPeriod;
  }
}

void Blink(byte PIN, int DELAY_MS)
{
  pinMode(PIN, OUTPUT);
  digitalWrite(PIN,HIGH);
  delay(DELAY_MS);
  digitalWrite(PIN,LOW);
}