/***************************************************************************
    copyright           : (C) 2011 by Mathias Panzenböck
    email               : grosser.meister.morti@gmx.net
 ***************************************************************************/

/***************************************************************************
 *   This library is free software; you can redistribute it and/or modify  *
 *   it under the terms of the GNU Lesser General Public License version   *
 *   2.1 as published by the Free Software Foundation.                     *
 *                                                                         *
 *   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                                                       *
 *                                                                         *
 *   Alternatively, this file is available under the Mozilla Public        *
 *   License Version 1.1.  You may obtain a copy of the License at         *
 *   http://www.mozilla.org/MPL/                                           *
 ***************************************************************************/


#include "modfile.h"
#include "tstringlist.h"
#include "tdebug.h"
#include "modfileprivate.h"
#include "tpropertymap.h"

using namespace Strawberry_TagLib::TagLib;
using namespace Mod;

class Mod::File::FilePrivate {
 public:
  explicit FilePrivate(AudioProperties::ReadStyle propertiesStyle) : properties(propertiesStyle) {}

  Mod::Tag tag;
  Mod::AudioProperties properties;
};

Mod::File::File(FileName file, bool readProperties, AudioProperties::ReadStyle propertiesStyle) : Mod::FileBase(file), d(new FilePrivate(propertiesStyle)) {

  if (isOpen())
    read(readProperties);

}

Mod::File::File(IOStream *stream, bool readProperties, AudioProperties::ReadStyle propertiesStyle) : Mod::FileBase(stream), d(new FilePrivate(propertiesStyle)) {

  if (isOpen())
    read(readProperties);

}

Mod::File::~File() {
  delete d;
}

Mod::Tag *Mod::File::tag() const {
  return &d->tag;
}

Mod::AudioProperties *Mod::File::audioProperties() const {
  return &d->properties;
}

bool Mod::File::save() {

  if (readOnly()) {
    debug("Mod::File::save() - Cannot save to a read only file.");
    return false;
  }
  seek(0);
  writeString(d->tag.title(), 20);
  StringList lines = d->tag.comment().split("\n");
  size_t n = std::min<size_t>(lines.size(), d->properties.instrumentCount());
  for (size_t i = 0; i < n; ++i) {
    writeString(lines[i], 22);
    seek(8, Current);
  }

  for (size_t i = n; i < d->properties.instrumentCount(); ++i) {
    writeString(String(), 22);
    seek(8, Current);
  }
  return true;

}

void Mod::File::read(bool) {

  if (!isOpen())
    return;

  seek(1080);
  ByteVector modId = readBlock(4);
  READ_ASSERT(modId.size() == 4);

  int channels = 4;
  unsigned int instruments = 31;
  if (modId == "M.K." || modId == "M!K!" || modId == "M&K!" || modId == "N.T.") {
    d->tag.setTrackerName("ProTracker");
    channels = 4;
  }
  else if (modId.startsWith("FLT") || modId.startsWith("TDZ")) {
    d->tag.setTrackerName("StarTrekker");
    char digit = modId[3];
    READ_ASSERT(digit >= '0' && digit <= '9');
    channels = digit - '0';
  }
  else if (modId.endsWith("CHN")) {
    d->tag.setTrackerName("StarTrekker");
    char digit = modId[0];
    READ_ASSERT(digit >= '0' && digit <= '9');
    channels = digit - '0';
  }
  else if (modId == "CD81" || modId == "OKTA") {
    d->tag.setTrackerName("Atari Oktalyzer");
    channels = 8;
  }
  else if (modId.endsWith("CH") || modId.endsWith("CN")) {
    d->tag.setTrackerName("TakeTracker");
    char digit = modId[0];
    READ_ASSERT(digit >= '0' && digit <= '9');
    channels = (digit - '0') * 10;
    digit = modId[1];
    READ_ASSERT(digit >= '0' && digit <= '9');
    channels += digit - '0';
  }
  else {
    // Not sure if this is correct. I'd need a file
    // created with NoiseTracker to check this.
    d->tag.setTrackerName("NoiseTracker");  // probably
    channels = 4;
    instruments = 15;
  }
  d->properties.setChannels(channels);
  d->properties.setInstrumentCount(instruments);

  seek(0);
  READ_STRING(d->tag.setTitle, 20);

  StringList comment;
  for (unsigned int i = 0; i < instruments; ++i) {
    READ_STRING_AS(instrumentName, 22);
    // value in words, * 2 (<< 1) for bytes:
    READ_U16B_AS(sampleLength);

    READ_BYTE_AS(fineTuneByte);
    int fineTune = fineTuneByte & 0xF;
    // > 7 means negative value
    if (fineTune > 7) fineTune -= 16;

    READ_BYTE_AS(volume);
    if (volume > 64) volume = 64;
    // volume in decibels: 20 * log10(volume / 64)

    // value in words, * 2 (<< 1) for bytes:
    READ_U16B_AS(repeatStart);
    // value in words, * 2 (<< 1) for bytes:
    READ_U16B_AS(repatLength);

    comment.append(instrumentName);
  }

  READ_BYTE(d->properties.setLengthInPatterns);

  d->tag.setComment(comment.toString("\n"));

}