/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */

/*

 * This file is part of the libe-book project.

 *

 * This Source Code Form is subject to the terms of the Mozilla Public

 * License, v. 2.0. If a copy of the MPL was not distributed with this

 * file, You can obtain one at http://mozilla.org/MPL/2.0/.

 */

#include <cassert>

#include <string>

#include <vector>

#include <librevenge-stream/librevenge-stream.h>

#include "libebook_utils.h"

#include "EBOOKStreamView.h"

#include "PDBParser.h"

using std::unique_ptr;

namespace libebook

{

namespace

{

struct HeaderData

{

  HeaderData();

  std::string m_name;

  unsigned m_version;

  unsigned m_appInfoID;

  unsigned m_sortInfoID;

  unsigned m_type;

  unsigned m_creator;

  unsigned m_nextRecordListID;

  unsigned m_numberOfRecords;

  std::vector<unsigned> m_recordOffsets;

};

}

namespace

{

HeaderData::HeaderData()

  : m_name()

  , m_version(0)

  , m_appInfoID(0)

  , m_sortInfoID(0)

  , m_type(0)

  , m_creator(0)

  , m_nextRecordListID(0)

  , m_numberOfRecords(0)

  , m_recordOffsets()

{

}

}

struct PDBParserImpl

{

  PDBParserImpl(librevenge::RVNGInputStream *input, librevenge::RVNGTextInterface *document);

  HeaderData m_header;

  librevenge::RVNGInputStream *m_input;

  librevenge::RVNGTextInterface *m_document;

private:

// disable copying

  PDBParserImpl(const PDBParserImpl &other);

  PDBParserImpl &operator=(const PDBParserImpl &other);

};

PDBParserImpl::PDBParserImpl(librevenge::RVNGInputStream *const input, librevenge::RVNGTextInterface *const document)

  : m_header()

  , m_input(input)

  , m_document(document)

{

}

PDBParser::PDBParser(librevenge::RVNGInputStream *const input, librevenge::RVNGTextInterface *const document,

                     const unsigned type, const unsigned creator)

  : m_impl(new PDBParserImpl(input, document))

{

  readHeader();

  if ((type != m_impl->m_header.m_type) || (creator != m_impl->m_header.m_creator))

    throw UnsupportedFormat();

  if ((0 == m_impl->m_header.m_numberOfRecords)

      || (m_impl->m_header.m_recordOffsets.size() != m_impl->m_header.m_numberOfRecords))

    throw UnsupportedFormat();

}

PDBParser::~PDBParser()

{

}

bool PDBParser::parse()

{

  if (m_impl->m_header.m_appInfoID)

  {

    // TODO: implement me

  }

  if (m_impl->m_header.m_sortInfoID)

  {

    // TODO: implement me

  }

  {

    std::unique_ptr<librevenge::RVNGInputStream> input(getRecordStream(0));

    readIndexRecord(input.get());

  }

  readDataRecords();

  return true;

}

librevenge::RVNGTextInterface *PDBParser::getDocument() const

{

  return m_impl->m_document;

}

const char *PDBParser::getName() const

{

  return m_impl->m_header.m_name.c_str();

}

librevenge::RVNGInputStream *PDBParser::getAppInfoRecord() const

{

  // TODO: implement me

  return nullptr;

}

librevenge::RVNGInputStream *PDBParser::getIndexRecord() const

{

  return getRecordStream(0);

}

unsigned PDBParser::getDataRecordCount() const

{

  return m_impl->m_header.m_numberOfRecords - 1;

}

librevenge::RVNGInputStream *PDBParser::getDataRecord(unsigned n) const

{

  return getRecordStream(n + 1);

}

librevenge::RVNGInputStream *PDBParser::getDataRecords() const

{

  const auto begin = (long) m_impl->m_header.m_recordOffsets[1];

  m_impl->m_input->seek(0, librevenge::RVNG_SEEK_END);

  const long end = m_impl->m_input->tell();

  return new EBOOKStreamView(m_impl->m_input, begin, end);

}

librevenge::RVNGInputStream *PDBParser::getDataRecords(unsigned first, unsigned last) const

{

  if (first >= last)

    return nullptr;

  if ((m_impl->m_header.m_numberOfRecords - 1) < last)

    return nullptr;

  const auto begin = (long) m_impl->m_header.m_recordOffsets[first + 1];

  long end = 0;

  if ((m_impl->m_header.m_numberOfRecords - 1) == last) // ends with the last record

  {

    m_impl->m_input->seek(0, librevenge::RVNG_SEEK_END);

    end = m_impl->m_input->tell();

  }

  else

    end = (long) m_impl->m_header.m_recordOffsets[last + 1];

  return new EBOOKStreamView(m_impl->m_input, begin, end);

}

void PDBParser::readDataRecords()

{

  for (unsigned i = 1; i != m_impl->m_header.m_numberOfRecords; ++i)

  {

    unique_ptr<librevenge::RVNGInputStream> record(getRecordStream(i));

    readDataRecord(record.get(), m_impl->m_header.m_numberOfRecords - 1 == i);

  }

}

void PDBParser::readHeader()

{

  m_impl->m_input->seek(0, librevenge::RVNG_SEEK_SET);

  char name[32];

  unsigned nameLen = 0;

  while (nameLen != 32)

  {

    unsigned char c = readU8(m_impl->m_input);

    name[nameLen++] = (char) c;

    if (0 == c)

      break;

  }

  // We read the whole name, but there was no terminating 0. Either a

  // broken file or not a PDB file at all...

  if (nameLen == 32)

    --nameLen;

  name[nameLen] = 0;

  m_impl->m_header.m_name.assign(name, nameLen);

  // skip the unused bytes of name and ignore 2 bytes of attributes

  m_impl->m_input->seek(34, librevenge::RVNG_SEEK_SET);

  m_impl->m_header.m_version = readU16(m_impl->m_input, true);

  // ignore dates, modification number and IDs; 6*4 = 24 bytes

  skip(m_impl->m_input, 24);

  m_impl->m_header.m_type = readU32(m_impl->m_input, true);

  m_impl->m_header.m_creator = readU32(m_impl->m_input, true);

  skip(m_impl->m_input, 4); // skip uniqueIDseed

  m_impl->m_header.m_nextRecordListID = readU32(m_impl->m_input, true);

  assert(m_impl->m_input->tell() == 76);

  m_impl->m_header.m_numberOfRecords = readU16(m_impl->m_input, true);

  if (m_impl->m_header.m_numberOfRecords > getRemainingLength(m_impl->m_input) / 8)

    m_impl->m_header.m_numberOfRecords = getRemainingLength(m_impl->m_input) / 8;

  // read records

  for (unsigned i = 0; i != m_impl->m_header.m_numberOfRecords; ++i)

  {

    m_impl->m_header.m_recordOffsets.push_back(readU32(m_impl->m_input, true));

    skip(m_impl->m_input, 4); // skip the uninteresting remainder

  }

}

librevenge::RVNGInputStream *PDBParser::getRecordStream(const unsigned n) const

{

  if (n >= m_impl->m_header.m_numberOfRecords)

    return nullptr;

  const auto begin = (long) m_impl->m_header.m_recordOffsets[n];

  long end = 0;

  if ((m_impl->m_header.m_numberOfRecords - 1) == n) // the last record

  {

    m_impl->m_input->seek(0, librevenge::RVNG_SEEK_END);

    end = m_impl->m_input->tell();

  }

  else

    end = (long) m_impl->m_header.m_recordOffsets[n + 1];

  return new EBOOKStreamView(m_impl->m_input, begin, end);

}

}

/* vim:set shiftwidth=2 softtabstop=2 expandtab: */