/*
 * Adplug - Replayer for many OPL2/OPL3 audio file formats.
 * Copyright (C) 1999 - 2006 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
 *
 * imf.cpp - IMF Player by Simon Peter <dn.tlp@gmx.net>
 *
 * FILE FORMAT:
 * There seem to be 2 different flavors of IMF formats out there. One version
 * contains just the raw IMF music data. In this case, the first word of the
 * file is always 0 (because the music data starts this way). This is already
 * the music data! So read in the entire file and play it.
 *
 * If this word is greater than 0, it specifies the size of the following
 * song data in bytes. In this case, the file has a footer that contains
 * arbitrary infos about it. Mostly, this is plain ASCII text with some words
 * of the author. Read and play the specified amount of song data and display
 * the remaining data as ASCII text.
 *
 * NOTES:
 * This player handles the two above mentioned formats, as well as a third
 * type, invented by Martin Fernandez <mfernan@cnba.uba.ar>, that's got a
 * proper header to add title/game name information. After the header starts
 * the normal IMF file in one of the two above mentioned formats.
 *
 * This player also handles a special footer format by Adam Nielsen,
 * which has defined fields of information about the song, the author
 * and more.
 */

#include <string.h>

#include "imf.h"
#include "database.h"

/*** public methods *************************************/

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

bool
CimfPlayer::load (VFSFile * fd, const CFileProvider & fp)
{
  binistream *f = fp.open (fd);
  if (!f)
    return false;
  unsigned long fsize, flsize, mfsize = 0;
  unsigned int i;

  // file validation section
  {
    char header[5];
    int version;

    f->readString (header, 5);
    version = f->readInt (1);

    if (strncmp (header, "ADLIB", 5) || version != 1)
    {
      if (!fp.extension (vfs_get_filename (fd), ".imf") && !fp.extension (vfs_get_filename (fd), ".wlf"))
      {
        // It's no IMF file at all
        fp.close (f);
        return false;
      }
      else
        f->seek (0);            // It's a normal IMF file
    }
    else
    {
      // It's a IMF file with header
      track_name = f->readString ('\0');
      game_name = f->readString ('\0');
      f->ignore (1);
      mfsize = f->pos () + 2;
    }
  }

  // load section
  if (mfsize)
    fsize = f->readInt (4);
  else
    fsize = f->readInt (2);
  flsize = fp.filesize (f);
  if (!fsize)
  {                             // footerless file (raw music data)
    if (mfsize)
      f->seek (-4, binio::Add);
    else
      f->seek (-2, binio::Add);
    size = (flsize - mfsize) / 4;
  }
  else                          // file has got a footer
    size = fsize / 4;

  data = new Sdata[size];
  for (i = 0; i < size; i++)
  {
    data[i].reg = f->readInt (1);
    data[i].val = f->readInt (1);
    data[i].time = f->readInt (2);
  }

  // read footer, if any
  if (fsize && (fsize < flsize - 2 - mfsize))
  {
    if (f->readInt (1) == 0x1a)
    {
      // Adam Nielsen's footer format
      track_name = f->readString ();
      author_name = f->readString ();
      remarks = f->readString ();
    }
    else
    {
      // Generic footer
      unsigned long footerlen = flsize - fsize - 2 - mfsize;

      footer = new char[footerlen + 1];
      f->readString (footer, footerlen);
      footer[footerlen] = '\0'; // Make ASCIIZ string
    }
  }

  rate = getrate (vfs_get_filename (fd), fp, f);
  fp.close (f);
  rewind (0);
  return true;
}

bool
CimfPlayer::update ()
{
  do
  {
    opl->write (data[pos].reg, data[pos].val);
    del = data[pos].time;
    pos++;
  } while (!del && pos < size);

  if (pos >= size)
  {
    pos = 0;
    songend = true;
  }
  else
    timer = rate / (float) del;

  return !songend;
}

void
CimfPlayer::rewind (int subsong)
{
  pos = 0;
  del = 0;
  timer = rate;
  songend = false;
  opl->init ();
  opl->write (1, 32);           // go to OPL2 mode
}

std::string CimfPlayer::gettitle ()
{
  std::string title;

  title = track_name;

  if (!track_name.empty () && !game_name.empty ())
    title += " - ";

  title += game_name;

  return title;
}

std::string CimfPlayer::getdesc ()
{
  std::string desc;

  if (footer)
    desc = std::string (footer);

  if (!remarks.empty () && footer)
    desc += "\n\n";

  desc += remarks;

  return desc;
}

/*** private methods *************************************/

float
CimfPlayer::getrate (const std::string & filename, const CFileProvider & fp,
                     binistream * f)
{
  if (db)
  {                             // Database available
    f->seek (0, binio::Set);
    CClockRecord *record =
      (CClockRecord *) db->search (CAdPlugDatabase::CKey (*f));
    if (record && record->type == CAdPlugDatabase::CRecord::ClockSpeed)
      return record->clock;
  }

  // Otherwise the database is either unavailable, or there's no entry for this file
  if (fp.extension (filename, ".imf"))
    return 560.0f;
  if (fp.extension (filename, ".wlf"))
    return 700.0f;
  return 700.0f;                // default speed for unknown files that aren't .IMF or .WLF
}
