/*
 * LogManager.h
 *
 * Copyright (C) 2008 Matthias Schiffer <matthias@gamezock.de>
 *
 * This program is free software: you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by the
 * Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 * See the GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program. If not, see <http://www.gnu.org/licenses/>.
 */

#ifndef MAD_COMMON_LOGMANAGER_H_
#define MAD_COMMON_LOGMANAGER_H_

#include <config.h>

#include "Configurable.h"
#include "Logger.h"
#include "RemoteLogger.h"

#include <queue>
#include <set>

#include "glthread/lock.h"
#include "glthread/cond.h"

namespace Mad {
namespace Common {

class ThreadManager;

class LogManager : public Configurable {
  private:
    friend class ThreadManager;

    typedef LoggerBase::MessageCategory MessageCategory;
    typedef LoggerBase::MessageLevel MessageLevel;

    struct Message {
      MessageCategory category;
      MessageLevel level;
      time_t timestamp;
      std::string message;
    };

    struct RemoteMessage {
      MessageCategory category;
      MessageLevel level;
      time_t timestamp;
      std::string message;
      std::string source;
    };

    class ConsoleLogger : public Logger, public RemoteLogger {
      private:
        // For long messages, writing to cerr is not atomic
        // -> lock cerr to prevent mixing messages up
        gl_lock_t cerrLock;

      protected:
        virtual void logMessage(MessageCategory category _UNUSED_PARAMETER_, MessageLevel level, time_t timestamp _UNUSED_PARAMETER_, const std::string &message);
        virtual void logMessage(MessageCategory category _UNUSED_PARAMETER_, MessageLevel, time_t timestamp _UNUSED_PARAMETER_, const std::string &message, const std::string &messageSource);

      public:
        ConsoleLogger() {}

        void logMessageDirect(MessageCategory category _UNUSED_PARAMETER_, MessageLevel level _UNUSED_PARAMETER_, time_t timestamp _UNUSED_PARAMETER_, const std::string &message);
    };


    static LogManager logManager;

    ConsoleLogger consoleLogger;

    std::set<Logger*> loggers;
    std::set<RemoteLogger*> remoteLoggers;
    bool configured, running;

    gl_lock_t lock;
    gl_cond_t queueCond;

    gl_lock_t loggerLock;
    gl_lock_t remoteLoggerLock;

    std::queue<Message> messageQueue;
    std::queue<RemoteMessage> remoteMessageQueue;

    void loggerThread();
    void stopLoggerThread() {
      gl_lock_lock(lock);
      running = false;
      gl_cond_signal(queueCond);
      gl_lock_unlock(lock);
    }

    LogManager() : configured(false), running(false) {
      gl_lock_init(lock);
      gl_lock_init(loggerLock);
      gl_lock_init(remoteLoggerLock);
    }

  protected:
    virtual bool handleConfigEntry(const ConfigEntry &entry, bool handled);
    virtual void configFinished();

  public:
    ~LogManager() {
      gl_lock_destroy(remoteLoggerLock);
      gl_lock_destroy(loggerLock);
      gl_lock_destroy(lock);
    }

    void log(MessageCategory category, MessageLevel level, time_t timestamp, const std::string &message);
    void log(MessageCategory category, MessageLevel level, time_t timestamp, const std::string &message, const std::string &source);

    void registerLogger(Logger *logger) {
      gl_lock_lock(loggerLock);
      loggers.insert(logger);
      gl_lock_unlock(loggerLock);
    }

    void unregisterLogger(Logger *logger) {
      gl_lock_lock(loggerLock);
      loggers.erase(logger);
      gl_lock_unlock(loggerLock);
    }

    void registerLogger(RemoteLogger *logger) {
      gl_lock_lock(remoteLoggerLock);
      remoteLoggers.insert(logger);
      gl_lock_unlock(remoteLoggerLock);
    }

    void unregisterLogger(RemoteLogger *logger) {
      gl_lock_lock(remoteLoggerLock);
      remoteLoggers.erase(logger);
      gl_lock_unlock(remoteLoggerLock);
    }

    static LogManager *get() {
      return &logManager;
    }
};

}
}

#endif /* MAD_COMMON_LOGMANAGER_H_ */