/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You 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.
 */

#pragma once

#ifndef GEODE_LOG_H_
#define GEODE_LOG_H_

#include <cstdio>
#include <cstdarg>
#include <string>

#include <geode/internal/geode_globals.hpp>
#include <geode/util/LogLevel.hpp>

/******************************************************************************/

#ifndef GEODE_HIGHEST_LOG_LEVEL
#define GEODE_HIGHEST_LOG_LEVEL LogLevel::All
#endif

#ifndef GEODE_MAX_LOG_FILE_LIMIT
#define GEODE_MAX_LOG_FILE_LIMIT (1024 * 1024 * 1024)
#endif

#ifndef GEODE_MAX_LOG_DISK_LIMIT
#define GEODE_MAX_LOG_DISK_LIMIT (1024ll * 1024ll * 1024ll * 1024ll)
#endif

#define _GF_MSG_LIMIT 8192

/******************************************************************************/

/** @file
 */

namespace apache {
namespace geode {
namespace client {

class Exception;

/******************************************************************************/
/******************************************************************************/

/* Logs the message if the given level is less than or equal to the current
 * logging level. */
#define GF_LOG(level, expr)                             \
  if (level > apache::geode::client::Log::logLevel()) { \
  } else                                                \
    apache::geode::client::Log::log(level, expr)

/** Defines methods available to clients that want to write a log message
 * to their Geode system's shared log file.
 * <p>
 * This class must be initialized prior to its use:
 * @ref Log::init
 * <p>
 * For any logged message the log file will contain:
 * <ul>
 * <li> The message's level.
 * <li> The time the message was logged.
 * <li> The id of the connection and thread that logged the message.
 * <li> The message itself which can be a const char* (perhaps with
 * an exception including the exception's stack trace.
 * </ul>
 * <p>
 * A message always has a level.
 * Logging levels are ordered. Enabling logging at a given level also
 * enables logging at higher levels. The higher the level the more
 * important and urgent the message.
 * <p>
 * The levels, in descending order of severity, are:
 * <ul>
 *
 * <li> <code>error</code> (highest severity) is a message level
 * indicating a serious failure.  In general <code>error</code>
 * messages should describe events that are of considerable
 * importance and which will prevent normal program execution. They
 * should be reasonably intelligible to end users and to system
 * administrators.
 *
 * <li> <code>warning</code> is a message level indicating a
 * potential problem.  In general <code>warning</code> messages
 * should describe events that will be of interest to end users or
 * system managers, or which indicate potential problems.
 *
 * <li> <code>info</code> is a message level for informational
 * messages.  Typically <code>info</code> messages should be
 * reasonably significant and should make sense to end users and
 * system administrators.
 *
 * <li> <code>config</code> is a message level for static
 * configuration messages.  <code>config</code> messages are intended
 * to provide a variety of static configuration information, to
 * assist in debugging problems that may be associated with
 * particular configurations.
 *
 * <li> <code>fine</code> is a message level providing tracing
 * information.  In general the <code>fine</code> level should be
 * used for information that will be broadly interesting to
 * developers. This level is for the lowest volume, and most
 * important, tracing messages.
 *
 * <li> <code>finer</code> indicates a moderately detailed tracing
 * message.  This is an intermediate level between <code>fine</code>
 * and <code>finest</code>.
 *
 * <li> <code>finest</code> indicates a very detailed tracing
 * message.  Logging calls for entering, returning, or throwing an
 * exception are traced at the <code>finest</code> level.
 *
 * <li> <code>debug</code> (lowest severity) indicates a highly
 * detailed tracing message.  In general the <code>debug</code> level
 * should be used for the most voluminous detailed tracing messages.
 * </ul>
 *
 * <p>
 * For each level methods exist that will request a message, at that
 * level, to be logged. These methods are all named after their level.
 * <p>
 * For each level a method exists that indicates if messages at that
 * level will currently be logged. The names of these methods are of
 * the form: <em>level</em><code>Enabled</code>.
 *
 *
 */

class APACHE_GEODE_EXPORT Log {
 public:
  /******/

  /******/

  /**
   * Returns the current log level.
   */
  static LogLevel logLevel() { return s_logLevel; }

  /**
   * Set the current log level.
   */
  static void setLogLevel(LogLevel level) { s_logLevel = level; }

  /**
   * @return the name of the current log file.
   * NOTE: This function is for debugging only, as it is not completely
   * thread-safe!
   */
  static const char* logFileName();

  /**
   * Initializes logging facility with given level and filenames.
   * This method is called automatically within @ref DistributedSystem::connect
   * with the log-file, log-level, and log-file-size system properties used as
   * arguments
   */
  static void init
      // 0 => use maximum value (currently 1G)
      (LogLevel level, const char* logFileName, int32_t logFileLimit = 0,
       int64_t logDiskSpaceLimit = 0);

  /**
   * closes logging facility (until next init).
   */
  static void close();

  /**
   * returns character string for given log level. The string will be
   * identical to the enum declaration above, except it will be all
   * lower case. Out of range values will throw
   * IllegalArgumentException.
   */
  static const char* levelToChars(LogLevel level);

  /**
   * returns log level specified by "chars", or throws
   * IllegalArgumentException.  Allowed values are identical to the
   * enum declaration above for LogLevel, but with character case ignored.
   */
  static LogLevel charsToLevel(const std::string& chars);

  /**
   * Fills the provided buffer with formatted log-line given the level
   * and returns the buffer. This assumes that the buffer has large
   * enough space left to hold the formatted log-line (around 70 chars).
   *
   * This is provided so that applications wishing to use the same format
   * as Geode log-lines can do so easily. A log-line starts with the prefix
   * given below which is filled in by this method:
   * [<level> <date> <time> <timezone> <host>:<process ID> <thread ID>]
   *
   * This method is not thread-safe for the first invocation.
   * When invoking from outside either <init> should have been invoked,
   * or at least the first invocation should be single-threaded.
   */
  static char* formatLogLine(char* buf, LogLevel level);

  /******/

  /**
   * Returns whether log messages at given level are enabled.
   */
  static bool enabled(LogLevel level) {
    return (((s_doingDebug && level == LogLevel::Debug) ||
             GEODE_HIGHEST_LOG_LEVEL >= level) &&
            s_logLevel >= level);
  }

  /**
   * Logs a message at given level.
   */
  static void log(LogLevel level, const char* msg) {
    if (enabled(level)) put(level, msg);
  }

  /**
   * Logs both a message and thrown exception.
   */
  static void logThrow(LogLevel level, const char* msg, const Exception& ex) {
    if (enabled(level)) putThrow(level, msg, ex);
  }

  /**
   * Logs both a message and caught exception.
   */
  static void logCatch(LogLevel level, const char* msg, const Exception& ex) {
    if (enabled(level)) putCatch(level, msg, ex);
  }

  /******/

  /**
   * Returns whether "error" log messages are enabled.
   */
  static bool errorEnabled() {
    return GEODE_HIGHEST_LOG_LEVEL >= LogLevel::Error &&
           s_logLevel >= LogLevel::Error;
  }

  /**
   * Logs a message.
   * The message level is "error".
   */
  static void error(const char* msg) {
    if (errorEnabled()) put(LogLevel::Error, msg);
  }

  /**
   * Logs both a message and thrown exception.
   * The message level is "error".
   */
  static void errorThrow(const char* msg, const Exception& ex) {
    if (errorEnabled()) putThrow(LogLevel::Error, msg, ex);
  }

  /**
   * Writes both a message and caught exception.
   * The message level is "error".
   */
  static void errorCatch(const char* msg, const Exception& ex) {
    if (errorEnabled()) putCatch(LogLevel::Error, msg, ex);
  }

  /******/

  /**
   * Returns whether "warning" log messages are enabled.
   */
  static bool warningEnabled() {
    return GEODE_HIGHEST_LOG_LEVEL >= LogLevel::Warning &&
           s_logLevel >= LogLevel::Warning;
  }

  /**
   * Logs a message.
   * The message level is "warning".
   */
  static void warning(const char* msg) {
    if (warningEnabled()) put(LogLevel::Warning, msg);
  }

  /**
   * Logs both a message and thrown exception.
   * The message level is "warning".
   */
  static void warningThrow(const char* msg, const Exception& ex) {
    if (warningEnabled()) putThrow(LogLevel::Warning, msg, ex);
  }

  /**
   * Writes both a message and caught exception.
   * The message level is "warning".
   */
  static void warningCatch(const char* msg, const Exception& ex) {
    if (warningEnabled()) putCatch(LogLevel::Warning, msg, ex);
  }

  /******/

  /**
   * Returns whether "info" log messages are enabled.
   */
  static bool infoEnabled() {
    return GEODE_HIGHEST_LOG_LEVEL >= LogLevel::Info &&
           s_logLevel >= LogLevel::Info;
  }

  /**
   * Logs a message.
   * The message level is "info".
   */
  static void info(const char* msg) {
    if (infoEnabled()) put(LogLevel::Info, msg);
  }

  /**
   * Logs both a message and thrown exception.
   * The message level is "info".
   */
  static void infoThrow(const char* msg, const Exception& ex) {
    if (infoEnabled()) putThrow(LogLevel::Info, msg, ex);
  }

  /**
   * Writes both a message and caught exception.
   * The message level is "info".
   */
  static void infoCatch(const char* msg, const Exception& ex) {
    if (infoEnabled()) putCatch(LogLevel::Info, msg, ex);
  }

  /******/

  /**
   * Returns whether "config" log messages are enabled.
   */
  static bool configEnabled() {
    return GEODE_HIGHEST_LOG_LEVEL >= LogLevel::Config &&
           s_logLevel >= LogLevel::Config;
  }

  /**
   * Logs a message.
   * The message level is "config".
   */
  static void config(const char* msg) {
    if (configEnabled()) put(LogLevel::Config, msg);
  }

  /**
   * Logs both a message and thrown exception.
   * The message level is "config".
   */
  static void configThrow(const char* msg, const Exception& ex) {
    if (configEnabled()) putThrow(LogLevel::Config, msg, ex);
  }

  /**
   * Writes both a message and caught exception.
   * The message level is "config".
   */
  static void configCatch(const char* msg, const Exception& ex) {
    if (configEnabled()) putCatch(LogLevel::Config, msg, ex);
  }

  /******/

  /**
   * Returns whether "fine" log messages are enabled.
   */
  static bool fineEnabled() {
    return GEODE_HIGHEST_LOG_LEVEL >= LogLevel::Fine &&
           s_logLevel >= LogLevel::Fine;
  }

  /**
   * Logs a message.
   * The message level is "fine".
   */
  static void fine(const char* msg) {
    if (fineEnabled()) put(LogLevel::Fine, msg);
  }

  /**
   * Logs both a message and thrown exception.
   * The message level is "fine".
   */
  static void fineThrow(const char* msg, const Exception& ex) {
    if (fineEnabled()) putThrow(LogLevel::Fine, msg, ex);
  }

  /**
   * Writes both a message and caught exception.
   * The message level is "fine".
   */
  static void fineCatch(const char* msg, const Exception& ex) {
    if (fineEnabled()) putCatch(LogLevel::Fine, msg, ex);
  }

  /******/

  /**
   * Returns whether "finer" log messages are enabled.
   */
  static bool finerEnabled() {
    return GEODE_HIGHEST_LOG_LEVEL >= LogLevel::Finer &&
           s_logLevel >= LogLevel::Finer;
  }

  /**
   * Logs a message.
   * The message level is "finer".
   */
  static void finer(const char* msg) {
    if (finerEnabled()) put(LogLevel::Finer, msg);
  }

  /**
   * Logs both a message and thrown exception.
   * The message level is "finer".
   */
  static void finerThrow(const char* msg, const Exception& ex) {
    if (finerEnabled()) putThrow(LogLevel::Finer, msg, ex);
  }

  /**
   * Writes both a message and caught exception.
   * The message level is "finer".
   */
  static void finerCatch(const char* msg, const Exception& ex) {
    if (finerEnabled()) putCatch(LogLevel::Finer, msg, ex);
  }

  /******/

  /**
   * Returns whether "finest" log messages are enabled.
   */
  static bool finestEnabled() {
    return GEODE_HIGHEST_LOG_LEVEL >= LogLevel::Finest &&
           s_logLevel >= LogLevel::Finest;
  }

  /**
   * Logs a message.
   * The message level is "finest".
   */
  static void finest(const char* msg) {
    if (finestEnabled()) put(LogLevel::Finest, msg);
  }

  /**
   * Logs both a message and thrown exception.
   * The message level is "finest".
   */
  static void finestThrow(const char* msg, const Exception& ex) {
    if (finestEnabled()) putThrow(LogLevel::Finest, msg, ex);
  }

  /**
   * Writes both a message and caught exception.
   * The message level is "finest".
   */
  static void finestCatch(const char* msg, const Exception& ex) {
    if (finestEnabled()) putCatch(LogLevel::Finest, msg, ex);
  }

  /******/

  /**
   * Returns whether "debug" log messages are enabled.
   */
  static bool debugEnabled() {
    return (s_doingDebug || GEODE_HIGHEST_LOG_LEVEL >= LogLevel::Debug) &&
           s_logLevel >= LogLevel::Debug;
  }

  /**
   * Logs a message.
   * The message level is "debug".
   */
  static void debug(const char* msg) {
    if (debugEnabled()) put(LogLevel::Debug, msg);
  }

  /**
   * Logs both a message and thrown exception.
   * The message level is "debug".
   */
  static void debugThrow(const char* msg, const Exception& ex) {
    if (debugEnabled()) putThrow(LogLevel::Debug, msg, ex);
  }

  /**
   * Writes both a message and caught exception.
   * The message level is "debug".
   */
  static void debugCatch(const char* msg, const Exception& ex) {
    if (debugEnabled()) putCatch(LogLevel::Debug, msg, ex);
  }

  /******/

  static void enterFn(LogLevel level, const char* functionName);

  static void exitFn(LogLevel level, const char* functionName);

  /******/

 private:
  static LogLevel s_logLevel;

  /******/

#ifdef DEBUG
  enum { s_doingDebug = 1 };
#else
  enum { s_doingDebug = 0 };
#endif

  /******/

  static void writeBanner();

  /******/
 public:
  static void put(LogLevel level, const std::string& msg);

  static void put(LogLevel level, const char* msg);

  static void putThrow(LogLevel level, const char* msg, const Exception& ex);

  static void putCatch(LogLevel level, const char* msg, const Exception& ex);
};

/******************************************************************************/
/******************************************************************************/

class LogFn {
  const char* m_functionName;
  LogLevel m_level;

 public:
  explicit LogFn(const char* functionName, LogLevel level = LogLevel::Finest)
      : m_functionName(functionName), m_level(level) {
    if (Log::enabled(m_level)) Log::enterFn(m_level, m_functionName);
  }

  ~LogFn() {
    if (Log::enabled(m_level)) Log::exitFn(m_level, m_functionName);
  }

 private:
  LogFn(const LogFn& rhs);           // never defined
  void operator=(const LogFn& rhs);  // never defined
};

/******************************************************************************/
/******************************************************************************/

/**
 * These functions are added to facilitate logging in printf format.
 */

class APACHE_GEODE_EXPORT LogVarargs {
 public:
  static void debug(const char* fmt, ...);
  static void error(const char* fmt, ...);
  static void warn(const char* fmt, ...);
  static void info(const char* fmt, ...);
  static void config(const char* fmt, ...);
  static void fine(const char* fmt, ...);
  static void finer(const char* fmt, ...);
  static void finest(const char* fmt, ...);

  inline static void debug(const std::string& message) {
    Log::put(LogLevel::Debug, message.c_str());
  }

  inline static void error(const std::string& message) {
    Log::put(LogLevel::Error, message.c_str());
  }

  inline static void warn(const std::string& message) {
    Log::put(LogLevel::Warning, message.c_str());
  }

  inline static void info(const std::string& message) {
    Log::put(LogLevel::Info, message.c_str());
  }

  inline static void config(const std::string& message) {
    Log::put(LogLevel::Config, message.c_str());
  }

  inline static void fine(const std::string& message) {
    Log::put(LogLevel::Fine, message.c_str());
  }

  inline static void finer(const std::string& message) {
    Log::put(LogLevel::Finer, message.c_str());
  }

  inline static void finest(const std::string& message) {
    Log::put(LogLevel::Finest, message.c_str());
  }
};
}  // namespace client
}  // namespace geode
}  // namespace apache

/************************ LOGDEBUG ***********************************/

#define LOGDEBUG                                  \
  if (::apache::geode::client::LogLevel::Debug <= \
      ::apache::geode::client::Log::logLevel())   \
  ::apache::geode::client::LogVarargs::debug

/************************ LOGERROR ***********************************/

#define LOGERROR                                  \
  if (::apache::geode::client::LogLevel::Error <= \
      ::apache::geode::client::Log::logLevel())   \
  ::apache::geode::client::LogVarargs::error

/************************ LOGWARN ***********************************/

#define LOGWARN                                     \
  if (::apache::geode::client::LogLevel::Warning <= \
      ::apache::geode::client::Log::logLevel())     \
  ::apache::geode::client::LogVarargs::warn

/************************ LOGINFO ***********************************/

#define LOGINFO                                  \
  if (::apache::geode::client::LogLevel::Info <= \
      ::apache::geode::client::Log::logLevel())  \
  ::apache::geode::client::LogVarargs::info

/************************ LOGCONFIG ***********************************/

#define LOGCONFIG                                  \
  if (::apache::geode::client::LogLevel::Config <= \
      ::apache::geode::client::Log::logLevel())    \
  ::apache::geode::client::LogVarargs::config

/************************ LOGFINE ***********************************/

#define LOGFINE                                  \
  if (::apache::geode::client::LogLevel::Fine <= \
      ::apache::geode::client::Log::logLevel())  \
  ::apache::geode::client::LogVarargs::fine

/************************ LOGFINER ***********************************/

#define LOGFINER                                  \
  if (::apache::geode::client::LogLevel::Finer <= \
      ::apache::geode::client::Log::logLevel())   \
  ::apache::geode::client::LogVarargs::finer

/************************ LOGFINEST ***********************************/

#define LOGFINEST                                  \
  if (::apache::geode::client::LogLevel::Finest <= \
      ::apache::geode::client::Log::logLevel())    \
  ::apache::geode::client::LogVarargs::finest

/******************************************************************************/

/******************************************************************************/

#endif  // GEODE_LOG_H_