/**
 * \file brilliantrussian.h
 * \brief M4RI and M4RM.
 *
 * \author Gregory Bard <bard@fordham.edu>
 * \author Martin Albrecht <martinralbrecht@googlemail.com>
 *
 * \note For reference see Gregory Bard; Accelerating Cryptanalysis with
 * the Method of Four Russians; 2006;
 * http://eprint.iacr.org/2006/251.pdf
 */

#ifndef M4RI_BRILLIANTRUSSIAN_H
#define M4RI_BRILLIANTRUSSIAN_H

 /*******************************************************************
 *
 *                 M4RI:  Linear Algebra over GF(2)
 *
 *    Copyright (C) 2007, 2008 Gregory Bard <bard@fordham.edu>
 *    Copyright (C) 2008-2010 Martin Albrecht <martinralbrecht@googlemail.com>
 *
 *  Distributed under the terms of the GNU General Public License (GPL)
 *  version 2 or higher.
 *
 *    This code 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.
 *
 *  The full text of the GPL is available at:
 *
 *                  http://www.gnu.org/licenses/
 *
 ********************************************************************/

#include <math.h>
#include <string.h>
#include <stdlib.h>

#include <m4ri/mzd.h>
#include <m4ri/mzp.h>

/**
 * \brief Constructs all possible \f$2^k\f$ row combinations using the gray
 * code table.
 * 
 * \param M matrix to generate the tables from
 * \param r the starting row
 * \param c the starting column (only exact up to block)
 * \param k
 * \param T prealloced matrix of dimension \f$2^k\f$ x m->ncols
 * \param L prealloced table of length \f$2^k\f$
 */

void mzd_make_table(mzd_t const *M, rci_t r, rci_t c, int k, mzd_t *T, rci_t *L);

/**
 * \brief The function looks up k bits from position i,startcol in
 * each row and adds the appropriate row from T to the row i.
 *
 * This process is iterated for i from startrow to stoprow
 * (exclusive).
 *
 * \param M Matrix to operate on
 * \param startrow top row which is operated on
 * \param endrow bottom row which is operated on
 * \param startcol Starting column for addition
 * \param k M4RI parameter
 * \param T contains the correct row to be added
 * \param L Contains row number to be added
 */

void mzd_process_rows(mzd_t *M, rci_t startrow, rci_t endrow, rci_t startcol, int k, mzd_t const *T, rci_t const *L);

/**
 * \brief Same as mzd_process_rows but works with two Gray code tables
 * in parallel.
 *
 * \param M Matrix to operate on
 * \param startrow top row which is operated on
 * \param endrow bottom row which is operated on
 * \param startcol Starting column for addition
 * \param k M4RI parameter
 * \param T0 contains the correct row to be added
 * \param L0 Contains row number to be added
 * \param T1 contains the correct row to be added
 * \param L1 Contains row number to be added
 */

void mzd_process_rows2(mzd_t *M, rci_t startrow, rci_t endrow, rci_t startcol, int k, mzd_t const *T0, rci_t const *L0, mzd_t const *T1, rci_t const *L1);

/**
 * \brief Same as mzd_process_rows but works with three Gray code tables
 * in parallel.
 *
 * \param M Matrix to operate on
 * \param startrow top row which is operated on
 * \param endrow bottom row which is operated on
 * \param startcol Starting column for addition
 * \param k M4RI parameter
 * \param T0 contains the correct row to be added
 * \param L0 Contains row number to be added
 * \param T1 contains the correct row to be added
 * \param L1 Contains row number to be added
 * \param T2 contains the correct row to be added
 * \param L2 Contains row number to be added
 */

void mzd_process_rows3(mzd_t *M, rci_t startrow, rci_t endrow, rci_t startcol, int k, 
                       mzd_t const *T0, rci_t const *L0, mzd_t const *T1, rci_t const *L1,
                       mzd_t const *T2, rci_t const *L2);

/**
 * \brief Same as mzd_process_rows but works with four Gray code tables
 * in parallel.
 *
 * \param M Matrix to operate on
 * \param startrow top row which is operated on
 * \param endrow bottom row which is operated on
 * \param startcol Starting column for addition
 * \param k M4RI parameter
 * \param T0 contains the correct row to be added
 * \param L0 Contains row number to be added
 * \param T1 contains the correct row to be added
 * \param L1 Contains row number to be added
 * \param T2 contains the correct row to be added
 * \param L2 Contains row number to be added
 * \param T3 contains the correct row to be added
 * \param L3 Contains row number to be added
 */

void mzd_process_rows4(mzd_t *M, rci_t startrow, rci_t endrow, rci_t startcol, int k,
                       mzd_t const *T0, rci_t const *L0, mzd_t const *T1, rci_t const *L1,
                       mzd_t const *T2, rci_t const *L2, mzd_t const *T3, rci_t const *L3);

/**
 * \brief Same as mzd_process_rows but works with five Gray code tables
 * in parallel.
 *
 * \param M Matrix to operate on
 * \param startrow top row which is operated on
 * \param endrow bottom row which is operated on
 * \param startcol Starting column for addition
 * \param k M4RI parameter
 * \param T0 contains the correct row to be added
 * \param L0 Contains row number to be added
 * \param T1 contains the correct row to be added
 * \param L1 Contains row number to be added
 * \param T2 contains the correct row to be added
 * \param L2 Contains row number to be added
 * \param T3 contains the correct row to be added
 * \param L3 Contains row number to be added
 * \param T4 contains the correct row to be added
 * \param L4 Contains row number to be added
 */

void mzd_process_rows5(mzd_t *M, rci_t startrow, rci_t endrow, rci_t startcol, int k,
                       mzd_t const *T0, rci_t const *L0, mzd_t const *T1, rci_t const *L1,
                       mzd_t const *T2, rci_t const *L2, mzd_t const *T3, rci_t const *L3,
                       mzd_t const *T4, rci_t const *L4);

/**
 * \brief Same as mzd_process_rows but works with six Gray code tables
 * in parallel.
 *
 * \param M Matrix to operate on
 * \param startrow top row which is operated on
 * \param endrow bottom row which is operated on
 * \param startcol Starting column for addition
 * \param k M4RI parameter
 * \param T0 contains the correct row to be added
 * \param L0 Contains row number to be added
 * \param T1 contains the correct row to be added
 * \param L1 Contains row number to be added
 * \param T2 contains the correct row to be added
 * \param L2 Contains row number to be added
 * \param T3 contains the correct row to be added
 * \param L3 Contains row number to be added
 * \param T4 contains the correct row to be added
 * \param L4 Contains row number to be added
 * \param T5 contains the correct row to be added
 * \param L5 Contains row number to be added
 */

void mzd_process_rows6(mzd_t *M, rci_t startrow, rci_t endrow, rci_t startcol, int k,
                       mzd_t const *T0, rci_t const *L0, mzd_t const *T1, rci_t const *L1,
                       mzd_t const *T2, rci_t const *L2, mzd_t const *T3, rci_t const *L3,
                       mzd_t const *T4, rci_t const *L4, mzd_t const *T5, rci_t const *L5);

/**
 * \brief Matrix elimination using the 'Method of the Four Russians'
 * (M4RI).
 *
 * The M4RI algorithm was proposed in Gregory Bard; Accelerating
 * Cryptanalysis with the Method of Four Russians; 2006;
 * http://eprint.iacr.org/2006/251
 *
 * Our implementatation is discussed in in Martin Albrecht and Clément
 * Pernet; Efficient Decomposition of Dense Matrices over GF(2);
 * http://arxiv.org/abs/1006.1744
 * 
 * \param M Matrix to be reduced.
 * \param full Return the reduced row echelon form, not only upper triangular form.
 * \param k M4RI parameter, may be 0 for auto-choose.
 *
 * \example tests/test_elimination.c
 * \example tests/bench_elimination.c
 * 
 * \return Rank of A.
 */

rci_t _mzd_echelonize_m4ri(mzd_t *A, const int full, int k, int heuristic, const double threshold);

/**
 * \brief Given a matrix in upper triangular form compute the reduced row
 * echelon form of that matrix.
 * 
 * \param M Matrix to be reduced.
 * \param k M4RI parameter, may be 0 for auto-choose.
 *
 *
 */

void mzd_top_echelonize_m4ri(mzd_t *M, int k);

/**
 * \brief Given a matrix in upper triangular form compute the reduced
 * row echelon form of that matrix but only start to do anything for
 * the pivot at (r,c).
 * 
 * \param A Matrix to be reduced.
 * \param k M4RI parameter, may be 0 for auto-choose.
 * \param r Row index.
 * \param c Column index.
 * \param max_r Only clear top max_r rows.
 *
 *
 */

rci_t _mzd_top_echelonize_m4ri(mzd_t *A, int k, rci_t r, rci_t c, rci_t max_r);

/**
 * \brief Invert the matrix src using Konrod's method.
 *
 * \param dst Matrix to hold the inverse (may be NULL)
 * \param src Matrix to be inverted.
 * \param k Table size parameter, may be 0 for automatic choice.
 *
 *
 * \return Inverse of src if src has full rank
 */

mzd_t *mzd_inv_m4ri(mzd_t *dst, const mzd_t* src, int k);

/**
 * \brief Matrix multiplication using Konrod's method, i.e. compute C
 * such that C == AB. 
 * 
 * This is the convenient wrapper function, please see _mzd_mul_m4rm
 * for authors and implementation details.
 *
 * \param C Preallocated product matrix, may be NULL for automatic creation.
 * \param A Input matrix A
 * \param B Input matrix B
 * \param k M4RI parameter, may be 0 for auto-choose.
 *
 *
 * \return Pointer to C.
 */

mzd_t *mzd_mul_m4rm(mzd_t *C, mzd_t const *A, mzd_t const *B, int k);


/**
 * Set C to C + AB using Konrod's method.
 *
 * This is the convenient wrapper function, please see _mzd_mul_m4rm
 * for authors and implementation details.
 *
 * \param C Preallocated product matrix, may be NULL for zero matrix.
 * \param A Input matrix A
 * \param B Input matrix B
 * \param k M4RI parameter, may be 0 for auto-choose.
 *
 *
 * \return Pointer to C.
 */

mzd_t *mzd_addmul_m4rm(mzd_t *C, mzd_t const *A, mzd_t const *B, int k);

/**
 * \brief Matrix multiplication using Konrod's method, i.e. compute C such
 * that C == AB.
 * 
 * This is the actual implementation.
 * 
 * This function is described in Martin Albrecht, Gregory Bard and
 * William Hart; Efficient Multiplication of Dense Matrices over
 * GF(2); pre-print available at http://arxiv.org/abs/0811.1714
 *
 * \param C Preallocated product matrix.
 * \param A Input matrix A
 * \param B Input matrix B
 * \param k M4RI parameter, may be 0 for auto-choose.
 * \param clear clear the matrix C first
 *
 * \author Martin Albrecht -- initial implementation
 * \author William Hart -- block matrix implementation, use of several
 * Gray code tables, general speed-ups
 *
 *
 * \return Pointer to C.
 */

mzd_t *_mzd_mul_m4rm(mzd_t *C, mzd_t const *A, mzd_t const *B, int k, int clear);


#endif // M4RI_BRILLIANTRUSSIAN_H
