/*
 * Adplug - Replayer for many OPL2/OPL3 audio file formats.
 * Copyright (C) 1999 - 2003 Simon Peter <dn.tlp@gmx.net>, et al.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 *
 * adtrack.cpp - Adlib Tracker 1.0 Loader by Simon Peter <dn.tlp@gmx.net>
 *
 * NOTES:
 * The original Adlib Tracker 1.0 is behaving a little different from the
 * official spec: The 'octave' integer from the instrument file is stored
 * "minus 1" from the actual value, underflowing from 0 to 0xffff.
 *
 * I also noticed that my player is playing everything transposed a few tones
 * higher than the original tracker. As far as i can see, my player perfectly
 * follows the official spec, so it "must" be the tracker that does something
 * wrong here...
 */

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

#include "adtrack.h"
#include "debug.h"

/*** Public methods ***/

CPlayer *
CadtrackLoader::factory (Copl * newopl)
{
  return new CadtrackLoader (newopl);
}

bool
CadtrackLoader::load (VFSFile * fd, const CFileProvider & fp)
{
  binistream *f = fp.open (fd);
  if (!f)
    return false;
  binistream *instf;
  char note[2];
  unsigned short rwp;
  unsigned char chp, octave, pnote = 0;
  int i, j;
  AdTrackInst myinst;
  std::string filename (vfs_get_filename (fd));

  // file validation
  if (!fp.extension (filename, ".sng") || fp.filesize (f) != 36000)
  {
    fp.close (f);
    return false;
  }

  // check for instruments file
  std::string instfilename (filename, 0, filename.find_last_of ('.'));
  instfilename += ".ins";
  AdPlug_LogWrite ("CadtrackLoader::load(,\"%s\"): Checking for \"%s\"...\n",
                   filename.c_str (), instfilename.c_str ());

  VFSFile *instfd = vfs_fopen (instfilename.c_str (), "rb");
  instf = fp.open (instfd);
  if (!instf || fp.filesize (instf) != 468)
  {
    fp.close (f);
    vfs_fclose (instfd);
    return false;
  }

  // give CmodPlayer a hint on what we're up to
  realloc_patterns (1, 1000, 9);
  realloc_instruments (9);
  realloc_order (1);
  init_trackord ();
  flags = NoKeyOn;
  (*order) = 0;
  length = 1;
  restartpos = 0;
  bpm = 120;
  initspeed = 3;

  // load instruments from instruments file
  for (i = 0; i < 9; i++)
  {
    for (j = 0; j < 2; j++)
    {
      myinst.op[j].appampmod = instf->readInt (2);
      myinst.op[j].appvib = instf->readInt (2);
      myinst.op[j].maintsuslvl = instf->readInt (2);
      myinst.op[j].keybscale = instf->readInt (2);
      myinst.op[j].octave = instf->readInt (2);
      myinst.op[j].freqrisevollvldn = instf->readInt (2);
      myinst.op[j].softness = instf->readInt (2);
      myinst.op[j].attack = instf->readInt (2);
      myinst.op[j].decay = instf->readInt (2);
      myinst.op[j].release = instf->readInt (2);
      myinst.op[j].sustain = instf->readInt (2);
      myinst.op[j].feedback = instf->readInt (2);
      myinst.op[j].waveform = instf->readInt (2);
    }
    convert_instrument (i, &myinst);
  }
  fp.close (instf);

  // load file
  for (rwp = 0; rwp < 1000; rwp++)
    for (chp = 0; chp < 9; chp++)
    {
      // read next record
      f->readString (note, 2);
      octave = f->readInt (1);
      f->ignore ();
      switch (*note)
      {
      case 'C':
        if (note[1] == '#')
          pnote = 2;
        else
          pnote = 1;
        break;
      case 'D':
        if (note[1] == '#')
          pnote = 4;
        else
          pnote = 3;
        break;
      case 'E':
        pnote = 5;
        break;
      case 'F':
        if (note[1] == '#')
          pnote = 7;
        else
          pnote = 6;
        break;
      case 'G':
        if (note[1] == '#')
          pnote = 9;
        else
          pnote = 8;
        break;
      case 'A':
        if (note[1] == '#')
          pnote = 11;
        else
          pnote = 10;
        break;
      case 'B':
        pnote = 12;
        break;
      case '\0':
        if (note[1] == '\0')
          tracks[chp][rwp].note = 127;
        else
        {
          fp.close (f);
          return false;
        }
        break;
      default:
        fp.close (f);
        return false;
      }
      if ((*note) != '\0')
      {
        tracks[chp][rwp].note = pnote + (octave * 12);
        tracks[chp][rwp].inst = chp + 1;
      }
    }

  fp.close (f);
  rewind (0);
  return true;
}

float
CadtrackLoader::getrefresh ()
{
  return 18.2f;
}

/*** Private methods ***/

void
CadtrackLoader::convert_instrument (unsigned int n, AdTrackInst * i)
{
  // Carrier "Amp Mod / Vib / Env Type / KSR / Multiple" register
  inst[n].data[2] = i->op[Carrier].appampmod ? 1 << 7 : 0;
  inst[n].data[2] += i->op[Carrier].appvib ? 1 << 6 : 0;
  inst[n].data[2] += i->op[Carrier].maintsuslvl ? 1 << 5 : 0;
  inst[n].data[2] += i->op[Carrier].keybscale ? 1 << 4 : 0;
  inst[n].data[2] += (i->op[Carrier].octave + 1) & 0xffff;  // Bug in original tracker
  // Modulator...
  inst[n].data[1] = i->op[Modulator].appampmod ? 1 << 7 : 0;
  inst[n].data[1] += i->op[Modulator].appvib ? 1 << 6 : 0;
  inst[n].data[1] += i->op[Modulator].maintsuslvl ? 1 << 5 : 0;
  inst[n].data[1] += i->op[Modulator].keybscale ? 1 << 4 : 0;
  inst[n].data[1] += (i->op[Modulator].octave + 1) & 0xffff;    // Bug in original tracker

  // Carrier "Key Scaling / Level" register
  inst[n].data[10] = (i->op[Carrier].freqrisevollvldn & 3) << 6;
  inst[n].data[10] += i->op[Carrier].softness & 63;
  // Modulator...
  inst[n].data[9] = (i->op[Modulator].freqrisevollvldn & 3) << 6;
  inst[n].data[9] += i->op[Modulator].softness & 63;

  // Carrier "Attack / Decay" register
  inst[n].data[4] = (i->op[Carrier].attack & 0x0f) << 4;
  inst[n].data[4] += i->op[Carrier].decay & 0x0f;
  // Modulator...
  inst[n].data[3] = (i->op[Modulator].attack & 0x0f) << 4;
  inst[n].data[3] += i->op[Modulator].decay & 0x0f;

  // Carrier "Release / Sustain" register
  inst[n].data[6] = (i->op[Carrier].release & 0x0f) << 4;
  inst[n].data[6] += i->op[Carrier].sustain & 0x0f;
  // Modulator...
  inst[n].data[5] = (i->op[Modulator].release & 0x0f) << 4;
  inst[n].data[5] += i->op[Modulator].sustain & 0x0f;

  // Channel "Feedback / Connection" register
  inst[n].data[0] = (i->op[Carrier].feedback & 7) << 1;

  // Carrier/Modulator "Wave Select" registers
  inst[n].data[8] = i->op[Carrier].waveform & 3;
  inst[n].data[7] = i->op[Modulator].waveform & 3;
}
