/*
TMRh20 2014 - Updated to work with optimized RF24 Arduino library
*/


/**
 * Example for efficient call-response using ack-payloads
 *
 * This example continues to make use of all the normal functionality of the radios including
 * the auto-ack and auto-retry features, but allows ack-payloads to be written optionlly as well.
 * This allows very fast call-response communication, with the responding radio never having to
 * switch out of Primary Receiver mode to send back a payload, but having the option to switch to
 * primary transmitter if wanting to initiate communication instead of respond to a commmunication.
 */

#include <cstdlib>
#include <iostream>
#include <sstream>
#include <string>
#include "./RF24.h"

using namespace std;

//
// Hardware configuration
//

// CE Pin, CSN Pin, SPI Speed

// Setup for GPIO 22 CE and GPIO 25 CSN with SPI Speed @ 1Mhz
//RF24 radio(RPI_V2_GPIO_P1_22, RPI_V2_GPIO_P1_18, BCM2835_SPI_SPEED_1MHZ);

// Setup for GPIO 22 CE and CE0 CSN with SPI Speed @ 4Mhz
//RF24 radio(RPI_V2_GPIO_P1_15, BCM2835_SPI_CS0, BCM2835_SPI_SPEED_4MHZ);

// Setup for GPIO 22 CE and CE1 CSN with SPI Speed @ 8Mhz
RF24 radio(RPI_V2_GPIO_P1_15, BCM2835_SPI_CS0, BCM2835_SPI_SPEED_8MHZ);



// Radio pipe addresses for the 2 nodes to communicate.
const uint64_t addresses[2] = { 0xABCDABCD71LL, 0x544d52687CLL };

bool role_ping_out = 1, role_pong_back = 0, role = 0;

uint8_t counter = 1;                                                          // A single byte to keep track of the data being sent back and forth


int main(int argc, char** argv){


  printf("RF24/examples/gettingstarted_call_response\n");

  radio.begin();
  radio.setAutoAck(1);                    // Ensure autoACK is enabled
  radio.enableAckPayload();               // Allow optional ack payloads
  radio.setRetries(1,15);                 // Smallest time between retries, max no. of retries
  radio.setPayloadSize(1);                // Here we are sending 1-byte payloads to test the call-response speed
  //radio.powerUp();
  radio.printDetails();                   // Dump the configuration of the rf unit for debugging


/********* Role chooser ***********/

  printf("\n ************ Role Setup ***********\n");
  string input = "";
  char myChar = {0};
  cout << "Choose a role: Enter 0 for pong_back, 1 for ping_out (CTRL+C to exit)\n>";
  getline(cin,input);

  if(input.length() == 1) {
	myChar = input[0];
	if(myChar == '0'){
		cout << "Role: Pong Back, awaiting transmission " << endl << endl;
	}else{  cout << "Role: Ping Out, starting transmission " << endl << endl;
		role = role_ping_out;
	}
  }
/***********************************/
  // This simple sketch opens two pipes for these two nodes to communicate
  // back and forth.

    if ( role == role_ping_out )    {
      radio.openWritingPipe(addresses[0]);
      radio.openReadingPipe(1,addresses[1]);
    }else{
      radio.openWritingPipe(addresses[1]);
      radio.openReadingPipe(1,addresses[0]);
      radio.startListening();
    }

// forever loop
while (1){


/****************** Ping Out Role ***************************/

  if (role == role_ping_out){                               // Radio is in ping mode

    uint8_t gotByte;                                           // Initialize a variable for the incoming response

    radio.stopListening();                                  // First, stop listening so we can talk.
    printf("Now sending %d as payload. ",counter);          // Use a simple byte counter as payload
    unsigned long time = millis();                          // Record the current microsecond count

    if ( radio.write(&counter,1) ){                         // Send the counter variable to the other radio
        if(!radio.available()){                             // If nothing in the buffer, we got an ack but it is blank
            printf("Got blank response. round-trip delay: %lu ms\n\r",millis()-time);
        }else{
            while(radio.available() ){                      // If an ack with payload was received
                radio.read( &gotByte, 1 );                  // Read it, and display the response time
                printf("Got response %d, round-trip delay: %lu ms\n\r",gotByte,millis()-time);
                counter++;                                  // Increment the counter variable
            }
        }

    }else{        printf("Sending failed.\n\r"); }          // If no ack response, sending failed

    sleep(1);  // Try again later
  }

/****************** Pong Back Role ***************************/

  if ( role == role_pong_back ) {
    uint8_t pipeNo, gotByte;                       // Declare variables for the pipe and the byte received
    while( radio.available(&pipeNo)){              // Read all available payloads
      radio.read( &gotByte, 1 );
                                                   // Since this is a call-response. Respond directly with an ack payload.
      		  				                       // Ack payloads are much more efficient than switching to transmit mode to respond to a call
      radio.writeAckPayload(pipeNo,&gotByte, 1 );  // This can be commented out to send empty payloads.
      printf("Sent response %d \n\r", gotByte);
   }
 }

} //while 1
} //main