/*
 * Copyright (C) 2013 Bastian Bloessl <bloessl@ccs-labs.org>
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
#ifndef INCLUDED_IEEE802_11_OFDM_UTILS_H
#define INCLUDED_IEEE802_11_OFDM_UTILS_H

#include <ieee802-11/api.h>

/**
 * Define structure for the MAC header of a data frame.
 * Values as stored as MSB, but standard mandates LSB
 * representation. Bit utils functions can help changing
 * endiannes
 */
struct MAC_DATAFRAME_HEADER {
    char frame_control[2];  //protocol version, type, subtype, to_ds, from_ds, ...
    char duration[2];       //duration field
    char address1[6];       //address 1 indicating BSSID: 6 bytes MAC address
    char address2[6];       //address 2 indicating receiver
    char address3[6];       //address 3 indicating sender
    char sequence[2];       //sequence number plus fragment number
};

enum ENCODING {
	BPSK_1_2  = 0,
	BPSK_3_4  = 1,
	QPSK_1_2  = 2,
	QPSK_3_4  = 3,
	QAM16_1_2 = 4,
	QAM16_3_4 = 5,
	QAM64_2_3 = 6,
	QAM64_3_4 = 7,
};

/**
 * OFDM parameters
 */
class ofdm_param {
public:
	ofdm_param(ENCODING e);

	// data rate
	ENCODING encoding;
	// rate field of the SIGNAL header
	char     rate_field;
	// number of coded bits per sub carrier
	int      n_bpsc;
	// number of coded bits per OFDM symbol
	int      n_cbps;
	// number of data bits per OFDM symbol
	int      n_dbps;

	void print_out();
};

/**
 * packet specific parameters
 */
class tx_param {
public:
	tx_param(ofdm_param &ofdm, int psdu_length);
	// PSDU size in bytes
	int psdu_size;
	// number of OFDM symbols (17-11)
	int n_sym;
	// number of data bits in the DATA field, including service and padding (17-12)
	int n_data;
	// number of padding bits in the DATA field (17-13)
	int n_pad;
	int n_encoded_bits;

	void print_out();
};

#endif /* INCLUDED_IEEE802_11_OFDM_UTILS_H */