/*
	TMRh20 2014 - Optimized RF24 Library Fork
*/

/**
 * Example using Dynamic Payloads
 *
 * This is an example of how to use payloads of a varying (dynamic) size.
 */

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

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

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

RF24 radio(22, 0); // CE GPIO, CSN SPI-BUS

int interruptPin = 23; // GPIO pin for interrupts

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

// Radio pipe addresses for the 2 nodes to communicate.
const uint64_t pipes[2] = {0xF0F0F0F0E1LL, 0xF0F0F0F0D2LL};

const int min_payload_size = 4;
const int max_payload_size = 32;
const int payload_size_increments_by = 1;
int next_payload_size = min_payload_size;

char receive_payload[max_payload_size + 1]; // +1 to allow room for a terminating NULL char
bool role_ping_out = 1, role_pong_back = 0;
bool role = 0;

void intHandler()
{
    //
    // 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
            uint8_t len = 0;

            while (radio.available()) {
                // Fetch the payload, and see if this was the last one.
                len = radio.getDynamicPayloadSize();
                radio.read(receive_payload, len);

                // Put a zero at the end for easy printing
                receive_payload[len] = 0;

                // Spew it
                printf("Got payload size=%i value=%s\n\r", len, receive_payload);
            }

            // First, stop listening so we can talk
            radio.stopListening();

            // Send the final one back.
            radio.write(receive_payload, len);
            printf("Sent response.\n\r");

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

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

    // Print preamble:
    cout << "RF24/examples/pingpair_dyn/\n";

    // Setup and configure rf radio
    radio.begin();
    radio.enableDynamicPayloads();
    radio.setRetries(5, 15);
    radio.printDetails();

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

    printf("\n ************ Role Setup ***********\n");
    string input = "";
    char myChar = {0};
    cout << "Choose a role: Enter 0 for receiver, 1 for transmitter (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;
        }
    }
    /***********************************/

    if (role == role_ping_out) {
        radio.openWritingPipe(pipes[0]);
        radio.openReadingPipe(1, pipes[1]);
    }
    else {
        radio.openWritingPipe(pipes[1]);
        radio.openReadingPipe(1, pipes[0]);
        radio.startListening();
    }
    attachInterrupt(interruptPin, INT_EDGE_FALLING, intHandler); //Attach interrupt to bcm pin 23

    // forever loop
    while (1) {

        if (role == role_ping_out) {
            // The payload will always be the same, what will change is how much of it we send.
            static char send_payload[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZ789012";

            // First, stop listening so we can talk.
            radio.stopListening();

            // Take the time, and send it.  This will block until complete
            printf("Now sending length %i...", next_payload_size);
            radio.write(send_payload, next_payload_size);

            // Now, continue listening
            radio.startListening();

            // Wait here until we get a response, or timeout
            unsigned long started_waiting_at = millis();
            bool timeout = false;
            while (!radio.available() && !timeout) {
                if (millis() - started_waiting_at > 500) {
                    timeout = true;
                }
            }

            // Describe the results
            if (timeout) {
                printf("Failed, response timed out.\n\r");
            }
            else {
                // Grab the response, compare, and send to debugging spew
                uint8_t len = radio.getDynamicPayloadSize();
                radio.read(receive_payload, len);

                // Put a zero at the end for easy printing
                receive_payload[len] = 0;

                // Spew it
                printf("Got response size=%i value=%s\n\r", len, receive_payload);
            }

            // Update size for next time.
            next_payload_size += payload_size_increments_by;
            if (next_payload_size > max_payload_size) {
                next_payload_size = min_payload_size;
            }

            // Try again 1s later
            delay(100);
        }
    }
}
