/*
 Copyright (C) 2011 J. Coliz <maniacbug@ymail.com>

 This program is free software; you can redistribute it and/or
 modify it under the terms of the GNU General Public License
 version 2 as published by the Free Software Foundation.

 03/17/2013 : Charles-Henri Hallard (http://hallard.me)
              Modified to use with Arduipi board http://hallard.me/arduipi
						  Changed to use modified bcm2835 and RF24 library
TMRh20 2014 - Updated to work with optimized RF24 Arduino library

 */

/**
 * Example RF Radio Ping Pair
 *
 * This is an example of how to use the RF24 class on RPi, communicating to an Arduino running
 * the GettingStarted sketch.
 */

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

using namespace std;
//
// Hardware configuration
// Configure the appropriate pins for your connections

/****************** Linux ***********************/
// Radio CE Pin, CSN Pin, SPI Speed
// CE Pin uses GPIO number with BCM and SPIDEV drivers, other platforms use their own pin numbering
// CS Pin addresses the SPI bus number at /dev/spidev<a>.<b>
// ie: RF24 radio(<ce_pin>, <a>*10+<b>); spidev1.0 is 10, spidev1.1 is 11 etc..

// Generic:
RF24 radio(22,0);

/****************** Linux (BBB,x86,etc) ***********************/
// See http://tmrh20.github.io/RF24/pages.html for more information on usage
// See http://iotdk.intel.com/docs/master/mraa/ for more information on MRAA
// See https://www.kernel.org/doc/Documentation/spi/spidev for more information on SPIDEV


/********** User Config *********/
// Assign a unique identifier for this node, 0 or 1
bool radioNumber = 1;

/********************************/

// Radio pipe addresses for the 2 nodes to communicate.
const uint8_t pipes[][6] = {"1Node", "2Node"};

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

    bool role_ping_out = true, role_pong_back = false;
    bool role = role_pong_back;

    cout << "RF24/examples/GettingStarted/\n";

    // Setup and configure rf radio
    radio.begin();

    // optionally, increase the delay between retries & # of retries
    radio.setRetries(15, 15);
    // Dump the configuration of the rf unit for debugging
    radio.printDetails();


    /********* 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 (!radioNumber) {
        radio.openWritingPipe(pipes[0]);
        radio.openReadingPipe(1, pipes[1]);
    } else {
        radio.openWritingPipe(pipes[1]);
        radio.openReadingPipe(1, pipes[0]);
    }

    radio.startListening();

    // forever loop
    while (1) {
        if (role == role_ping_out) {
            // First, stop listening so we can talk.
            radio.stopListening();

            // Take the time, and send it.  This will block until complete

            printf("Now sending...\n");
            unsigned long time = millis();

            bool ok = radio.write(&time, sizeof(unsigned long));

            if (!ok) {
                printf("failed.\n");
            }
            // Now, continue listening
            radio.startListening();

            // Wait here until we get a response, or timeout (250ms)
            unsigned long started_waiting_at = millis();
            bool timeout = false;
            while (!radio.available() && !timeout) {
                if (millis() - started_waiting_at > 200) {
                    timeout = true;
                }
            }


            // Describe the results
            if (timeout) {
                printf("Failed, response timed out.\n");
            } else {
                // Grab the response, compare, and send to debugging spew
                unsigned long got_time;
                radio.read(&got_time, sizeof(unsigned long));

                // Spew it
                printf("Got response %lu, round-trip delay: %lu\n", got_time, millis() - got_time);
            }
            sleep(1);
        }

        //
        // Pong back role.  Receive each packet, dump it out, and send it back
        //

        if (role == role_pong_back) {

            // if there is data ready
            if (radio.available()) {
                // Dump the payloads until we've gotten everything
                unsigned long got_time;

                // Fetch the payload, and see if this was the last one.
                while (radio.available()) {
                    radio.read(&got_time, sizeof(unsigned long));
                }
                radio.stopListening();

                radio.write(&got_time, sizeof(unsigned long));

                // Now, resume listening so we catch the next packets.
                radio.startListening();

                // Spew it
                printf("Got payload(%d) %lu...\n", sizeof(unsigned long), got_time);

                delay(925); //Delay after payload responded to, minimize RPi CPU time

            }

        }

    } // forever loop

    return 0;
}