////////////////////////////////////////////////////////////////////////////////
/// DISCLAIMER
///
/// Copyright 2014-2017 ArangoDB GmbH, Cologne, Germany
/// Copyright 2004-2014 triAGENS GmbH, Cologne, Germany
///
/// Licensed under the Apache License, Version 2.0 (the "License");
/// you may not use this file except in compliance with the License.
/// You may obtain a copy of the License at
///
///     http://www.apache.org/licenses/LICENSE-2.0
///
/// Unless required by applicable law or agreed to in writing, software
/// distributed under the License is distributed on an "AS IS" BASIS,
/// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
/// See the License for the specific language governing permissions and
/// limitations under the License.
///
/// Copyright holder is ArangoDB GmbH, Cologne, Germany
///
/// @author Daniel H. Larkin
////////////////////////////////////////////////////////////////////////////////

#include "Views/LoggerView.h"
#include "Basics/Common.h"
#include "Basics/Result.h"
#include "Logger/Logger.h"
#include "VocBase/LogicalView.h"
#include "VocBase/ViewImplementation.h"
#include "VocBase/voc-types.h"

#include <velocypack/Builder.h>
#include <velocypack/Slice.h>

using namespace arangodb;

static LogLevel LevelStringToEnum(std::string const& level) {
  if (level == "ERR") {
    return LogLevel::ERR;
  }

  if (level == "WARN") {
    return LogLevel::WARN;
  }

  if (level == "INFO") {
    return LogLevel::INFO;
  }

  if (level == "DEBUG") {
    return LogLevel::DEBUG;
  }

  return LogLevel::TRACE;
}

static std::string LevelEnumToString(LogLevel level) {
  switch (level) {
    case LogLevel::ERR:
      return "ERR";
    case LogLevel::WARN:
      return "WARN";
    case LogLevel::INFO:
      return "INFO";
    case LogLevel::DEBUG:
      return "DEBUG";
    default:
      return "TRACE";
  }
}

#define VIEW_LOG_TOPIC(a)                                               \
  !arangodb::Logger::isEnabled(static_cast<arangodb::LogLevel>(a),      \
                               Logger::VIEWS)                           \
      ? (void)0                                                         \
      : arangodb::LogVoidify() & (arangodb::LoggerStream()              \
                                  << static_cast<arangodb::LogLevel>(a) \
                                  << Logger::VIEWS                      \
                                  << arangodb::Logger::LINE(__LINE__)   \
                                  << arangodb::Logger::FILE(__FILE__)   \
                                  << arangodb::Logger::FUNCTION(__FUNCTION__))

std::string LoggerView::type("logger");

std::unique_ptr<ViewImplementation> LoggerView::creator(
    LogicalView* view, arangodb::velocypack::Slice const& info, bool isNew) {
  LOG_TOPIC(TRACE, Logger::VIEWS)
      << "called LoggerView::creator with data: " << info.toJson()
      << ", isNew: " << isNew;

  return std::make_unique<LoggerView>(ConstructionGuard(), view, info, isNew);
}

LoggerView::LoggerView(ConstructionGuard const&, LogicalView* logical,
                       arangodb::velocypack::Slice const& info, bool isNew)
    : ViewImplementation(logical, info) {
  VPackSlice properties = info.get("properties");
  if (!properties.isObject()) {
    _level = LogLevel::TRACE;
    return;
  }

  VPackSlice levelSlice = properties.get("level");
  if (!levelSlice.isString()) {
    _level = LogLevel::TRACE;
    return;
  }

  std::string levelString = levelSlice.copyString();
  _level = LevelStringToEnum(levelString);
}

arangodb::Result LoggerView::updateProperties(
    arangodb::velocypack::Slice const& slice, bool partialUpdate, bool doSync) {
  VIEW_LOG_TOPIC(_level)
      << "called LoggerView::updateProperties with data " << slice.toJson()
      << ". view data: "
      << _logicalView->toVelocyPack(true, false).slice().toJson();

  VPackSlice levelSlice = slice.get("level");
  if (!levelSlice.isString()) {
    return {TRI_ERROR_BAD_PARAMETER,
            "expecting <level> to be specified as string"};
  }

  std::string levelString = levelSlice.copyString();
  _level = LevelStringToEnum(levelString);

  return {};
}

/// @brief export properties
void LoggerView::getPropertiesVPack(velocypack::Builder& builder) const {
  VIEW_LOG_TOPIC(_level) << "called LoggerView::getPropertiesVPack";

  TRI_ASSERT(builder.isOpenObject());
  builder.add("level", VPackValue(LevelEnumToString(_level)));
  TRI_ASSERT(builder.isOpenObject());
}

/// @brief opens an existing view
void LoggerView::open() {
  VIEW_LOG_TOPIC(_level)
      << "called LoggerView::open. view data: "
      << _logicalView->toVelocyPack(true, false).slice().toJson();
}

void LoggerView::drop() {
  VIEW_LOG_TOPIC(_level)
      << "called LoggerView::drop. view data: "
      << _logicalView->toVelocyPack(true, false).slice().toJson();
}