// Copyright 2010-2020, Google Inc.
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
//     * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
//     * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following disclaimer
// in the documentation and/or other materials provided with the
// distribution.
//     * Neither the name of Google Inc. nor the names of its
// contributors may be used to endorse or promote products derived from
// this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

#include "dictionary/dictionary_impl.h"

#include <string>
#include <utility>

#include "base/logging.h"
#include "base/util.h"
#include "dictionary/dictionary_interface.h"
#include "dictionary/dictionary_token.h"
#include "dictionary/pos_matcher.h"
#include "dictionary/suppression_dictionary.h"
#include "protocol/commands.pb.h"
#include "absl/strings/string_view.h"

namespace mozc {
namespace dictionary {

DictionaryImpl::DictionaryImpl(
    std::unique_ptr<const DictionaryInterface> system_dictionary,
    std::unique_ptr<const DictionaryInterface> value_dictionary,
    DictionaryInterface *user_dictionary,
    const SuppressionDictionary *suppression_dictionary,
    const POSMatcher *pos_matcher)
    : pos_matcher_(pos_matcher),
      system_dictionary_(std::move(system_dictionary)),
      value_dictionary_(std::move(value_dictionary)),
      user_dictionary_(user_dictionary),
      suppression_dictionary_(suppression_dictionary) {
  CHECK(pos_matcher_);
  CHECK(system_dictionary_.get());
  CHECK(value_dictionary_.get());
  CHECK(user_dictionary_);
  CHECK(suppression_dictionary_);
  dics_.push_back(system_dictionary_.get());
  dics_.push_back(value_dictionary_.get());
  dics_.push_back(user_dictionary_);
}

DictionaryImpl::~DictionaryImpl() { dics_.clear(); }

bool DictionaryImpl::HasKey(absl::string_view key) const {
  for (size_t i = 0; i < dics_.size(); ++i) {
    if (dics_[i]->HasKey(key)) {
      return true;
    }
  }
  return false;
}

bool DictionaryImpl::HasValue(absl::string_view value) const {
  for (size_t i = 0; i < dics_.size(); ++i) {
    if (dics_[i]->HasValue(value)) {
      return true;
    }
  }
  return false;
}

namespace {

class CallbackWithFilter : public DictionaryInterface::Callback {
 public:
  CallbackWithFilter(const bool use_spelling_correction,
                     const bool use_zip_code_conversion,
                     const bool use_t13n_conversion,
                     const POSMatcher *pos_matcher,
                     const SuppressionDictionary *suppression_dictionary,
                     DictionaryInterface::Callback *callback)
      : use_spelling_correction_(use_spelling_correction),
        use_zip_code_conversion_(use_zip_code_conversion),
        use_t13n_conversion_(use_t13n_conversion),
        pos_matcher_(pos_matcher),
        suppression_dictionary_(suppression_dictionary),
        callback_(callback) {}

  ResultType OnKey(absl::string_view key) override {
    return callback_->OnKey(key);
  }

  ResultType OnActualKey(absl::string_view key, absl::string_view actual_key,
                         bool is_expanded) override {
    return callback_->OnActualKey(key, actual_key, is_expanded);
  }

  ResultType OnToken(absl::string_view key, absl::string_view actual_key,
                     const Token &token) override {
    if (!(token.attributes & Token::USER_DICTIONARY)) {
      if (!use_spelling_correction_ &&
          (token.attributes & Token::SPELLING_CORRECTION)) {
        return TRAVERSE_CONTINUE;
      }
      if (!use_zip_code_conversion_ && pos_matcher_->IsZipcode(token.lid)) {
        return TRAVERSE_CONTINUE;
      }
      if (!use_t13n_conversion_ &&
          Util::IsEnglishTransliteration(token.value)) {
        return TRAVERSE_CONTINUE;
      }
    }
    if (suppression_dictionary_->SuppressEntry(token.key, token.value)) {
      return TRAVERSE_CONTINUE;
    }
    return callback_->OnToken(key, actual_key, token);
  }

 private:
  const bool use_spelling_correction_;
  const bool use_zip_code_conversion_;
  const bool use_t13n_conversion_;
  const POSMatcher *pos_matcher_;
  const SuppressionDictionary *suppression_dictionary_;
  DictionaryInterface::Callback *callback_;
};

}  // namespace

void DictionaryImpl::LookupPredictive(
    absl::string_view key, const ConversionRequest &conversion_request,
    Callback *callback) const {
  CallbackWithFilter callback_with_filter(
      conversion_request.config().use_spelling_correction(),
      conversion_request.config().use_zip_code_conversion(),
      conversion_request.config().use_t13n_conversion(), pos_matcher_,
      suppression_dictionary_, callback);
  for (size_t i = 0; i < dics_.size(); ++i) {
    dics_[i]->LookupPredictive(key, conversion_request, &callback_with_filter);
  }
}

void DictionaryImpl::LookupPrefix(absl::string_view key,
                                  const ConversionRequest &conversion_request,
                                  Callback *callback) const {
  CallbackWithFilter callback_with_filter(
      conversion_request.config().use_spelling_correction(),
      conversion_request.config().use_zip_code_conversion(),
      conversion_request.config().use_t13n_conversion(), pos_matcher_,
      suppression_dictionary_, callback);
  for (size_t i = 0; i < dics_.size(); ++i) {
    dics_[i]->LookupPrefix(key, conversion_request, &callback_with_filter);
  }
}

void DictionaryImpl::LookupExact(absl::string_view key,
                                 const ConversionRequest &conversion_request,
                                 Callback *callback) const {
  CallbackWithFilter callback_with_filter(
      conversion_request.config().use_spelling_correction(),
      conversion_request.config().use_zip_code_conversion(),
      conversion_request.config().use_t13n_conversion(), pos_matcher_,
      suppression_dictionary_, callback);
  for (size_t i = 0; i < dics_.size(); ++i) {
    dics_[i]->LookupExact(key, conversion_request, &callback_with_filter);
  }
}

void DictionaryImpl::LookupReverse(absl::string_view str,
                                   const ConversionRequest &conversion_request,
                                   Callback *callback) const {
  CallbackWithFilter callback_with_filter(
      conversion_request.config().use_spelling_correction(),
      conversion_request.config().use_zip_code_conversion(),
      conversion_request.config().use_t13n_conversion(), pos_matcher_,
      suppression_dictionary_, callback);
  for (size_t i = 0; i < dics_.size(); ++i) {
    dics_[i]->LookupReverse(str, conversion_request, &callback_with_filter);
  }
}

bool DictionaryImpl::LookupComment(absl::string_view key,
                                   absl::string_view value,
                                   const ConversionRequest &conversion_request,
                                   std::string *comment) const {
  // TODO(komatsu): UserDictionary should be treated as the highest priority.
  // In the current implementation, UserDictionary is the last node of dics_,
  // but the only dictionary which may return true.
  for (size_t i = 0; i < dics_.size(); ++i) {
    if (dics_[i]->LookupComment(key, value, conversion_request, comment)) {
      return true;
    }
  }
  return false;
}

bool DictionaryImpl::Reload() { return user_dictionary_->Reload(); }

void DictionaryImpl::PopulateReverseLookupCache(absl::string_view str) const {
  for (size_t i = 0; i < dics_.size(); ++i) {
    dics_[i]->PopulateReverseLookupCache(str);
  }
}

void DictionaryImpl::ClearReverseLookupCache() const {
  for (size_t i = 0; i < dics_.size(); ++i) {
    dics_[i]->ClearReverseLookupCache();
  }
}

}  // namespace dictionary
}  // namespace mozc