/*
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 optionally 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 communication.
 */

#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

/****************** Raspberry Pi ***********************/

RF24 radio(22, 0);

/********** User Config *********/
// Assign a unique identifier for this node, 0 or 1. Arduino example uses radioNumber 0 by default.
bool radioNumber = 1;
int interruptPin = 23;
/********************************/

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

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
uint32_t timer = 0;

void intHandler()
{

    bool tx_ok, tx_fail, rx;
    radio.whatHappened(tx_ok, tx_fail, rx);

    if (tx_fail) {
        printf("Sending failed.\n\r");
    }

    if (role == role_ping_out && tx_ok) {
        if (!radio.available()) {
            printf("Got blank response. round-trip delay: %u ms\n\r", millis() - timer);
        }
    }

    if (role == role_ping_out) {
        while (radio.available()) {
            uint8_t gotByte;
            radio.read(&gotByte, 1);
            printf("Got response %d, round-trip delay: %u ms\n\r", gotByte, millis() - timer);
            counter++;
        }
    }

    if (role == role_pong_back) {
        if (tx_ok) {
            printf("Ack Payload Sent\n");
        }
        uint8_t pipeNo, gotByte;
        if (radio.available(&pipeNo)) {
            radio.read(&gotByte, 1);

            gotByte += 1;
            radio.writeAckPayload(pipeNo, &gotByte, 1);
            printf("Loaded next response %d \n\r", gotByte);
        }
    }
}

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

    cout << "RPi/RF24/examples/gettingstarted_call_response\n";
    radio.begin();
    radio.enableAckPayload();      // Allow optional ack payloads
    radio.enableDynamicPayloads(); // needed for using ACK payloads
    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 opens two pipes for these two nodes to communicate
    // back and forth.
    if (!radioNumber) {
        radio.openWritingPipe(addresses[0]);
        radio.openReadingPipe(1, addresses[1]);
    }
    else {
        radio.openWritingPipe(addresses[1]);
        radio.openReadingPipe(1, addresses[0]);
    }
    radio.startListening();
    radio.writeAckPayload(1, &counter, 1);

    attachInterrupt(interruptPin, INT_EDGE_FALLING, intHandler); //Attach interrupt to bcm pin 23

    // 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
            timer = millis();                               // Record the current microsecond count

            radio.startWrite(&counter, 1, false); // Send the counter variable to the other radio
            sleep(1);                             // Try again later
        }

        /****************** Pong Back Role ***************************/
        // This is done by using ACK payloads & IRQ

    } //while 1
} //main
