/*

 * 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.

 */

#ifndef _LOG4CXX_APPENDER_SKELETON_H

#define _LOG4CXX_APPENDER_SKELETON_H

#include <log4cxx/appender.h>

#include <log4cxx/layout.h>

#include <log4cxx/spi/errorhandler.h>

#include <log4cxx/spi/filter.h>

#include <log4cxx/helpers/object.h>

#include <log4cxx/helpers/pool.h>

#include <log4cxx/level.h>

namespace LOG4CXX_NS

{

/**

*  Implementation base class for all appenders.

*

*  This class provides the code for common functionality, such as

*  support for threshold filtering and support for general filters.

* */

class LOG4CXX_EXPORT AppenderSkeleton :

  public virtual Appender,

  public virtual helpers::Object

{

  protected:

    LOG4CXX_DECLARE_PRIVATE_MEMBER_PTR(AppenderSkeletonPrivate, m_priv)

    AppenderSkeleton(LOG4CXX_PRIVATE_PTR(AppenderSkeletonPrivate) priv);

    /**

    Subclasses of <code>AppenderSkeleton</code> must implement this

    method to perform actual logging. See also AppenderSkeleton::doAppend

    method.

    */

    virtual void append(const spi::LoggingEventPtr& event, helpers::Pool& p) = 0;

    /**

    * Compare \c event level against the appender threshold and check that \c event is accepted.

    * If \c event is accepted, delegate log output to the subclass implementation of

    * the AppenderSkeleton#append method.

    * */

    void doAppendImpl(const spi::LoggingEventPtr& event, helpers::Pool& pool);

    /**

    * Does no attached filter deny \c event or does an attached filter accept \c event?

    */

    bool isAccepted(const spi::LoggingEventPtr& event) const;

  public:

    DECLARE_ABSTRACT_LOG4CXX_OBJECT(AppenderSkeleton)

    BEGIN_LOG4CXX_CAST_MAP()

    LOG4CXX_CAST_ENTRY(AppenderSkeleton)

    LOG4CXX_CAST_ENTRY(Appender)

    LOG4CXX_CAST_ENTRY(spi::OptionHandler)

    END_LOG4CXX_CAST_MAP()

    AppenderSkeleton();

    AppenderSkeleton(const LayoutPtr& layout);

    virtual ~AppenderSkeleton();

    /**

    Finalize this appender by calling the derived class'

    <code>close</code> method.

    */

    void finalize();

    /**

    \copybrief spi::OptionHandler::activateOptions()

    No action is performed in this implementation.

    */

    void activateOptions(helpers::Pool& /* pool */) override {}

    /**

    \copybrief spi::OptionHandler::setOption()

    Supported options | Supported values | Default value |

    -------------- | ---------------- | --------------- |

    Name      | {any} | - |

    Threshold | Trace,Debug,Info,Warn,Error,Fatal,Off,All | All |

    */

    void setOption(const LogString& option, const LogString& value) override;

    /**

    Add a filter to end of the filter list.

    */

    void addFilter(const spi::FilterPtr newFilter) override;

  public:

    /**

    Clear the filters chain.

    */

    void clearFilters() override;

    /**

    Return the currently set spi::ErrorHandler for this

    Appender.

    */

    const spi::ErrorHandlerPtr getErrorHandler() const;

    /**

    Returns the head Filter.

    */

    spi::FilterPtr getFilter() const override;

    /**

    Return the first filter in the filter chain for this

    Appender. The return value may be <code>nullptr</code> if no is

    filter is set.

    */

    const spi::FilterPtr getFirstFilter() const;

    /**

    Returns the layout of this appender. The value may be nullptr.

    */

    LayoutPtr getLayout() const override;

    /**

    Returns the name of this Appender.

    */

    LogString getName() const override;

    /**

    Returns this appenders threshold level. See the #setThreshold

    method for the meaning of this option.

    */

    const LevelPtr getThreshold() const;

    /**

    Check whether the message level is below the appender's

    threshold. If there is no threshold set, then the return value is

    always <code>true</code>.

    */

    bool isAsSevereAsThreshold(const LevelPtr& level) const;

    /**

    * Call AppenderSkeleton#doAppendImpl after acquiring a lock

    * that prevents other threads from concurrently executing AppenderSkeleton#doAppendImpl.

    *

    * Reimplement this method in your appender if you use a different concurrency control technique.

    * */

    void doAppend(const spi::LoggingEventPtr& event, helpers::Pool& pool) override;

    /**

    Set the {@link spi::ErrorHandler ErrorHandler} for this Appender.

    */

    void setErrorHandler(const spi::ErrorHandlerPtr eh);

    /**

    Set the layout for this appender. Note that some appenders have

    their own (fixed) layouts or do not use one.

    */

    void setLayout(const LayoutPtr layout1) override;

    /**

    Set the name of this Appender.

    */

    void setName(const LogString& name1) override;

    /**

    Set the threshold level. All log events with lower level

    than the threshold level are ignored by the appender.

    <p>In configuration files this option is specified by setting the

    value of the <b>Threshold</b> option to a level

    string, such as "DEBUG", "INFO" and so on.

    */

    void setThreshold(const LevelPtr& threshold);

}; // class AppenderSkeleton

}  // namespace log4cxx

#endif //_LOG4CXX_APPENDER_SKELETON_H