/* -*- 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/.

 */

#ifdef HAVE_CONFIG_H

#include "config.h"

#endif

#include "EBOOKLanguageManager.h"

#include <cstdlib>

#include <stdexcept>

#ifdef WITH_LIBLANGTAG

#include <liblangtag/langtag.h>

#endif

#include "libebook_utils.h"

namespace libebook

{

using std::shared_ptr;

using std::unordered_map;

using std::unordered_set;

using librevenge::RVNGPropertyList;

using std::string;

#ifdef WITH_LIBLANGTAG

namespace

{

const shared_ptr<lt_tag_t> parseTag(const std::string &lang)

{

  const shared_ptr<lt_tag_t> tag(lt_tag_new(), lt_tag_unref);

  lt_error_t *error = nullptr;

  lt_tag_parse(tag.get(), lang.c_str(), &error);

  if (error && lt_error_is_set(error, LT_ERR_ANY))

  {

    lt_error_unref(error);

    return shared_ptr<lt_tag_t>();

  }

  return tag;

}

const std::string makeFullTag(const shared_ptr<lt_tag_t> &tag)

{

  lt_error_t *error = nullptr;

  const shared_ptr<char> full(lt_tag_transform(tag.get(), &error), std::free);

  if (error && lt_error_is_set(error, LT_ERR_ANY))

  {

    lt_error_unref(error);

    return lt_tag_get_string(tag.get());

  }

  return full.get();

}

}

#endif

struct EBOOKLanguageManager::LangDB

{

  LangDB();

  unordered_map<string, string> m_db;

};

EBOOKLanguageManager::LangDB::LangDB()

  : m_db()

{

#ifdef WITH_LIBLANGTAG

  shared_ptr<lt_lang_db_t> langDB(lt_db_get_lang(), lt_lang_db_unref);

  shared_ptr<lt_iter_t> it(LT_ITER_INIT(langDB.get()), lt_iter_finish);

  lt_pointer_t key(nullptr);

  lt_pointer_t value(nullptr);

  while (lt_iter_next(it.get(), &key, &value))

  {

    const auto *const tag = reinterpret_cast<const char *>(key);

    auto *const lang = reinterpret_cast<lt_lang_t *>(value);

    m_db[lt_lang_get_name(lang)] = tag;

  }

#endif

}

EBOOKLanguageManager::EBOOKLanguageManager()

  : m_tagMap()

  , m_invalidTags()

  , m_langMap()

  , m_invalidLangs()

  , m_propsMap()

  , m_langDB()

{

}

const std::string EBOOKLanguageManager::addTag(const std::string &tag)

{

#ifdef WITH_LIBLANGTAG

  // Check if the tag is already known

  const unordered_map<string, string>::const_iterator it = m_tagMap.find(tag);

  if (it != m_tagMap.end())

    return it->second;

  // Check if the tag was previously rejected as invalid

  const unordered_set<string>::const_iterator invIt = m_invalidTags.find(tag);

  if (invIt != m_invalidTags.end())

    return "";

  const shared_ptr<lt_tag_t> &langTag = parseTag(tag);

  if (!langTag)

  {

    m_invalidTags.insert(tag);

    return "";

  }

  const string fullTag(makeFullTag(langTag));

  m_tagMap[tag] = fullTag;

  addProperties(fullTag);

  return fullTag;

#else

  return tag;

#endif

}

const std::string EBOOKLanguageManager::addLanguage(const std::string &lang)

{

#ifdef WITH_LIBLANGTAG

  // Check if the lang is already known

  const unordered_map<string, string>::const_iterator it = m_langMap.find(lang);

  if (it != m_langMap.end())

    return it->second;

  // Check if the lang was previously rejected as invalid

  const unordered_set<string>::const_iterator invIt = m_invalidLangs.find(lang);

  if (invIt != m_invalidLangs.end())

    return "";

  const unordered_map<string, string>::const_iterator langIt = getLangDB().m_db.find(lang);

  if (langIt == getLangDB().m_db.end())

  {

    m_invalidLangs.insert(lang);

    return "";

  }

  const shared_ptr<lt_tag_t> &langTag = parseTag(langIt->second);

  if (!langTag)

    throw std::logic_error("cannot parse tag that came from liblangtag language DB");

  const string fullTag(makeFullTag(langTag));

  m_langMap[lang] = fullTag;

  addProperties(fullTag);

  return fullTag;

#else

  (void) lang;

  return "";

#endif

}

const std::string EBOOKLanguageManager::getLanguage(const std::string &tag) const

{

#ifdef WITH_LIBLANGTAG

  const shared_ptr<lt_tag_t> &langTag = parseTag(tag);

  if (!langTag)

    throw std::logic_error("cannot parse tag that has been successfully parsed before");

  return lt_lang_get_name(lt_tag_get_language(langTag.get()));

#else

  (void) tag;

  return "";

#endif

}

const EBOOKLanguageManager::LangDB &EBOOKLanguageManager::getLangDB() const

{

  if (!m_langDB)

    m_langDB.reset(new LangDB());

  return *m_langDB;

}

void EBOOKLanguageManager::addProperties(const std::string &tag)

{

#ifdef WITH_LIBLANGTAG

  const shared_ptr<lt_tag_t> &langTag = parseTag(tag);

  if (!langTag)

    throw std::logic_error("cannot parse tag that has been successfully parsed before");

  RVNGPropertyList props;

  const lt_lang_t *const lang = lt_tag_get_language(langTag.get());

  if (lang)

    props.insert("fo:language", lt_lang_get_tag(lang));

  const lt_region_t *const region = lt_tag_get_region(langTag.get());

  if (region)

    props.insert("fo:country", lt_region_get_tag(region));

  const lt_script_t *const script = lt_tag_get_script(langTag.get());

  if (script)

    props.insert("fo:script", lt_script_get_tag(script));

  m_propsMap[tag] = props;

#else

  (void) tag;

#endif

}

void EBOOKLanguageManager::writeProperties(const std::string &tag, librevenge::RVNGPropertyList &props) const

{

#ifdef WITH_LIBLANGTAG

  const unordered_map<string, RVNGPropertyList>::const_iterator it = m_propsMap.find(tag);

  if (it == m_propsMap.end())

  {

    EBOOK_DEBUG_MSG(("EBOOKLanguageManager::writeProperties: unknown tag %s\n", tag.c_str()));

    return;

  }

  for (RVNGPropertyList::Iter iter(it->second); !iter.last(); iter.next())

    props.insert(iter.key(), iter()->getStr());

#else

  (void) tag;

  (void) props;

#endif

}

}

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