/* -*- c++ -*- */
/* 
 * Copyright 2015 Free Software Foundation, Inc.
 * 
 * This 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, or (at your option)
 * any later version.
 * 
 * This software 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 software; see the file COPYING.  If not, write to
 * the Free Software Foundation, Inc., 51 Franklin Street,
 * Boston, MA 02110-1301, USA.
 */

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include <gnuradio/io_signature.h>
#include "dvb_bbscrambler_bb_impl.h"

namespace gr {
  namespace dtv {

    dvb_bbscrambler_bb::sptr
    dvb_bbscrambler_bb::make(dvb_standard_t standard, dvb_framesize_t framesize, dvb_code_rate_t rate)
    {
      return gnuradio::get_initial_sptr
        (new dvb_bbscrambler_bb_impl(standard, framesize, rate));
    }

    /*
     * The private constructor
     */
    dvb_bbscrambler_bb_impl::dvb_bbscrambler_bb_impl(dvb_standard_t standard, dvb_framesize_t framesize, dvb_code_rate_t rate)
      : gr::sync_block("dvb_bbscrambler_bb",
              gr::io_signature::make(1, 1, sizeof(unsigned char)),
              gr::io_signature::make(1, 1, sizeof(unsigned char)))
    {
      if (framesize == FECFRAME_NORMAL) {
        switch (rate) {
          case C1_4:
            kbch = 16008;
            break;
          case C1_3:
            kbch = 21408;
            break;
          case C2_5:
            kbch = 25728;
            break;
          case C1_2:
            kbch = 32208;
            break;
          case C3_5:
            kbch = 38688;
            break;
          case C2_3:
            kbch = 43040;
            break;
          case C3_4:
            kbch = 48408;
            break;
          case C4_5:
            kbch = 51648;
            break;
          case C5_6:
            kbch = 53840;
            break;
          case C8_9:
            kbch = 57472;
            break;
          case C9_10:
            kbch = 58192;
            break;
          case C13_45:
            kbch = 18528;
            break;
          case C9_20:
            kbch = 28968;
            break;
          case C90_180:
            kbch = 32208;
            break;
          case C96_180:
            kbch = 34368;
            break;
          case C11_20:
            kbch = 35448;
            break;
          case C100_180:
            kbch = 35808;
            break;
          case C104_180:
            kbch = 37248;
            break;
          case C26_45:
            kbch = 37248;
            break;
          case C18_30:
            kbch = 38688;
            break;
          case C28_45:
            kbch = 40128;
            break;
          case C23_36:
            kbch = 41208;
            break;
          case C116_180:
            kbch = 41568;
            break;
          case C20_30:
            kbch = 43008;
            break;
          case C124_180:
            kbch = 44448;
            break;
          case C25_36:
            kbch = 44808;
            break;
          case C128_180:
            kbch = 45888;
            break;
          case C13_18:
            kbch = 46608;
            break;
          case C132_180:
            kbch = 47328;
            break;
          case C22_30:
            kbch = 47328;
            break;
          case C135_180:
            kbch = 48408;
            break;
          case C140_180:
            kbch = 50208;
            break;
          case C7_9:
            kbch = 50208;
            break;
          case C154_180:
            kbch = 55248;
            break;
          default:
            kbch = 0;
            break;
        }
      }
      else {
        switch (rate) {
          case C1_4:
            kbch = 3072;
            break;
          case C1_3:
            kbch = 5232;
            break;
          case C2_5:
            kbch = 6312;
            break;
          case C1_2:
            kbch = 7032;
            break;
          case C3_5:
            kbch = 9552;
            break;
          case C2_3:
            kbch = 10632;
            break;
          case C3_4:
            kbch = 11712;
            break;
          case C4_5:
            kbch = 12432;
            break;
          case C5_6:
            kbch = 13152;
            break;
          case C8_9:
            kbch = 14232;
            break;
          case C11_45:
            kbch = 3792;
            break;
          case C4_15:
            kbch = 4152;
            break;
          case C14_45:
            kbch = 4872;
            break;
          case C7_15:
            kbch = 7392;
            break;
          case C8_15:
            kbch = 8472;
            break;
          case C26_45:
            kbch = 9192;
            break;
          case C32_45:
            kbch = 11352;
            break;
          default:
            kbch = 0;
            break;
        }
      }

      init_bb_randomiser();
      set_output_multiple(kbch);
    }

    /*
     * Our virtual destructor.
     */
    dvb_bbscrambler_bb_impl::~dvb_bbscrambler_bb_impl()
    {
    }

    void
    dvb_bbscrambler_bb_impl::init_bb_randomiser(void)
    {
      int sr = 0x4A80;
      for (int i = 0; i < FRAME_SIZE_NORMAL; i++) {
        int b = ((sr) ^ (sr >> 1)) & 1;
        bb_randomise[i] = b;
        sr >>= 1;
        if(b) {
          sr |= 0x4000;
        }
      }
    }

    int
    dvb_bbscrambler_bb_impl::work(int noutput_items,
                          gr_vector_const_void_star &input_items,
                          gr_vector_void_star &output_items)
    {
      const unsigned char *in = (const unsigned char *) input_items[0];
      unsigned char *out = (unsigned char *) output_items[0];

      for (int i = 0; i < noutput_items; i += kbch) {
        for (int j = 0; j < (int)kbch; ++j)
        {
          out[i + j] = in[i + j] ^ bb_randomise[j];
        }
      }

      // Tell runtime system how many output items we produced.
      return noutput_items;
    }

  } /* namespace dtv */
} /* namespace gr */

