opportunistic-xbee/protocol.h

#ifndef _PROTOCOL_H_
	#define _PROTOCOL_H_

	#include <Wire.h>

	#define DISCOVER_TTL     5000
	#define SENDERID         42
	#define MESSAGE_TTL      3

	#define OPCODE_DISCOVER 0
	#define OPCODE_MESSAGE  1

	// discover request (c.f. class node)
	#define DISCOVER_SIZE    sizeof(uint8_t)*3
	struct discover {
		uint8_t opcode; // opcode = 0
		uint8_t wave;   // id de la wave
		uint8_t dist;   // current node's distance
	};

  #define MESSAGE_MAX_PAYLOAD 255
  #define PROTO_MIN_SIZE 5 * sizeof(uint8_t)
	#define PROTO_SIZE (5 + MESSAGE_MAX_PAYLOAD) * sizeof(uint8_t)
  
	struct message {
		uint8_t opcode; // opcode = 1
		uint8_t sender; // sender id
		uint8_t dist;   // distance of the last sender
		uint8_t ttl;    // time to live default = 10
		uint8_t size;   // size of message in bytes
		uint8_t data[MESSAGE_MAX_PAYLOAD];  // actual message
	};

	class Node{
		private:
			uint8_t wave = 0;
			uint8_t dist = 255;

		public:
			getWave(){ return wave; }
			getDist(){ return dist; }

			bool update(uint8_t new_dist, uint8_t new_wave){
				// ignore if already setup for this wave
				if( new_wave == wave )
					return false;

				// update with new wave
				//
				// Note:
				// - We consider that we will receive lowest dist(ance)
				//   in the first receive of each wave because of the XBee stack
				wave = new_wave;
				dist = new_dist+1;
				return true;
			}
	};

#endif