// Module:  Log4CPLUS
// File:    appender.cxx
// Created: 6/2001
// Author:  Tad E. Smith
//
//
// Copyright 2003-2010 Tad E. Smith
//
// 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.

#include "dcmtk/oflog/appender.h"
#include "dcmtk/oflog/layout.h"
#include "dcmtk/oflog/logmacro.h"
#include "dcmtk/oflog/helpers/loglog.h"
#include "dcmtk/oflog/helpers/pointer.h"
#include "dcmtk/oflog/helpers/strhelp.h"
#include "dcmtk/oflog/helpers/property.h"
#include "dcmtk/oflog/spi/factory.h"
#include "dcmtk/oflog/spi/logevent.h"
#include "dcmtk/oflog/internal/internal.h"
#include "dcmtk/oflog/thread/syncpub.h"
#include <stdexcept>


namespace dcmtk
{
namespace log4cplus
{


///////////////////////////////////////////////////////////////////////////////
// log4cplus::ErrorHandler dtor
///////////////////////////////////////////////////////////////////////////////

ErrorHandler::ErrorHandler ()
{ }


ErrorHandler::~ErrorHandler()
{ }



///////////////////////////////////////////////////////////////////////////////
// log4cplus::OnlyOnceErrorHandler 
///////////////////////////////////////////////////////////////////////////////

OnlyOnceErrorHandler::OnlyOnceErrorHandler()
    : firstTime(true)
{ }


OnlyOnceErrorHandler::~OnlyOnceErrorHandler ()
{ }


void
OnlyOnceErrorHandler::error(const log4cplus::tstring& err)
{
    if(firstTime) {
        helpers::getLogLog().error(err);
        firstTime = false;
    }
}



void
OnlyOnceErrorHandler::reset()
{
    firstTime = true;
}



///////////////////////////////////////////////////////////////////////////////
// log4cplus::Appender ctors
///////////////////////////////////////////////////////////////////////////////

Appender::Appender()
 : layout(new SimpleLayout()),
   name( DCMTK_LOG4CPLUS_TEXT("") ),
   threshold(NOT_SET_LOG_LEVEL),
   filter(),
   errorHandler(new OnlyOnceErrorHandler),
   lockFile(),
   useLockFile(false),
   closed(false)
{
}



Appender::Appender(const log4cplus::helpers::Properties & properties)
    : layout(new SimpleLayout())
    , name()
    , threshold(NOT_SET_LOG_LEVEL)
    , filter()
    , errorHandler(new OnlyOnceErrorHandler)
    , lockFile()
    , useLockFile(false)
    , closed(false)
{
    if(properties.exists( DCMTK_LOG4CPLUS_TEXT("layout") ))
    {
        log4cplus::tstring const & factoryName
            = properties.getProperty( DCMTK_LOG4CPLUS_TEXT("layout") );
        spi::LayoutFactory* factory
            = spi::getLayoutFactoryRegistry().get(factoryName);
        if(factory == 0) {
            helpers::getLogLog().error(
                DCMTK_LOG4CPLUS_TEXT("Cannot find LayoutFactory: \"")
                + factoryName
                + DCMTK_LOG4CPLUS_TEXT("\"") );
            return;
        }

        helpers::Properties layoutProperties =
                properties.getPropertySubset( DCMTK_LOG4CPLUS_TEXT("layout.") );
        try {
            OFunique_ptr<Layout> newLayout(factory->createObject(layoutProperties));
            if(!newLayout) {
                helpers::getLogLog().error(
                    DCMTK_LOG4CPLUS_TEXT("Failed to create appender: ")
                    + factoryName);
            }
            else {
                layout = OFmove(newLayout);
            }
        }
        catch(STD_NAMESPACE exception const & e) {
            helpers::getLogLog().error( 
                DCMTK_LOG4CPLUS_TEXT("Error while creating Layout: ")
                + DCMTK_LOG4CPLUS_C_STR_TO_TSTRING(e.what()));
            return;
        }

    }

    // Support for appender.Threshold in properties configuration file
    if(properties.exists(DCMTK_LOG4CPLUS_TEXT("Threshold"))) {
        tstring tmp = properties.getProperty(DCMTK_LOG4CPLUS_TEXT("Threshold"));
        tmp = log4cplus::helpers::toUpper(tmp);
        threshold = log4cplus::getLogLevelManager().fromString(tmp);
    }

    // Configure the filters
    helpers::Properties filterProps
        = properties.getPropertySubset( DCMTK_LOG4CPLUS_TEXT("filters.") );
    unsigned filterCount = 0;
    spi::FilterPtr filterChain;
    tstring filterName;
    while (filterProps.exists(
        filterName = helpers::convertIntegerToString (++filterCount)))
    {
        tstring const & factoryName = filterProps.getProperty(filterName);
        spi::FilterFactory* factory
            = spi::getFilterFactoryRegistry().get(factoryName);

        if(! factory)
        {
            tstring err = DCMTK_LOG4CPLUS_TEXT("Appender::ctor()- Cannot find FilterFactory: ");
            helpers::getLogLog().error(err + factoryName);
            continue;
        }
        spi::FilterPtr tmpFilter = factory->createObject (
            filterProps.getPropertySubset(filterName + DCMTK_LOG4CPLUS_TEXT(".")));
        if (! tmpFilter)
        {
            tstring err = DCMTK_LOG4CPLUS_TEXT("Appender::ctor()- Failed to create filter: ");
            helpers::getLogLog().error(err + filterName);
        }
        if (! filterChain)
            filterChain = tmpFilter;
        else
            filterChain->appendFilter(tmpFilter);
    }
    setFilter(filterChain);

    properties.getBool (useLockFile, DCMTK_LOG4CPLUS_TEXT("UseLockFile"));
    if (useLockFile)
    {
        tstring const & lockFileName
            = properties.getProperty (DCMTK_LOG4CPLUS_TEXT ("LockFile"));
        if (! lockFileName.empty ())
        {
            try
            {
                lockFile.reset (new helpers::LockFile (lockFileName));
            }
            catch (STD_NAMESPACE runtime_error const &)
            {
                return;
            }
        }
        else
        {
            helpers::getLogLog ().debug (
                DCMTK_LOG4CPLUS_TEXT (
                    "UseLockFile is true but LockFile is not specified"));
        }
    }
}


Appender::~Appender()
{ }



///////////////////////////////////////////////////////////////////////////////
// log4cplus::Appender public methods
///////////////////////////////////////////////////////////////////////////////

void
Appender::destructorImpl()
{
    helpers::getLogLog().debug(  DCMTK_LOG4CPLUS_TEXT("Destroying appender named [")
        + name
        + DCMTK_LOG4CPLUS_TEXT("]."));

    // An appender might be closed then destroyed. There is no
    // point in closing twice.
    if(closed)
        return;

    close();
    closed = true;
}



void
Appender::doAppend(const log4cplus::spi::InternalLoggingEvent& event)
{
    thread::MutexGuard guard (access_mutex);

    if(closed) {
        helpers::getLogLog().error(
            DCMTK_LOG4CPLUS_TEXT("Attempted to append to closed appender named [")
            + name
            + DCMTK_LOG4CPLUS_TEXT("]."));
        return;
    }

    // Check appender's threshold logging level.

    if (! isAsSevereAsThreshold(event.getLogLevel()))
        return;

    // Evaluate filters attached to this appender.

    if (spi::checkFilter(filter.get(), event) == spi::DENY)
        return;

    // Lock system wide lock.

    helpers::LockFileGuard lfguard;
    if (useLockFile && lockFile.get ())
    {
        try
        {
            lfguard.attach_and_lock (*lockFile);
        }
        catch (STD_NAMESPACE runtime_error const &)
        {
            return;
        }
    }

    // Finally append given event.

    append(event);
}


tstring &
Appender::formatEvent (const spi::InternalLoggingEvent& event) const
{
    internal::appender_sratch_pad & appender_sp = internal::get_appender_sp ();
    detail::clear_tostringstream (appender_sp.oss);
    layout->formatAndAppend(appender_sp.oss, event);
    //appender_sp.oss.str().swap (appender_sp.str);
    appender_sp.str.assign(appender_sp.oss.str().c_str(), appender_sp.oss.str().length());
    return appender_sp.str;
}


log4cplus::tstring
Appender::getName()
{
    return name;
}



void
Appender::setName(const log4cplus::tstring& n)
{
    this->name = n;
}


ErrorHandler*
Appender::getErrorHandler()
{
    return errorHandler.get();
}



void
Appender::setErrorHandler(OFunique_ptr<ErrorHandler> eh)
{
    if (! eh.get())
    {
        // We do not throw exception here since the cause is probably a
        // bad config file.
        helpers::getLogLog().warn(
            DCMTK_LOG4CPLUS_TEXT("You have tried to set a null error-handler."));
        return;
    }

    thread::MutexGuard guard (access_mutex);

    this->errorHandler = OFmove(eh);
}



void
Appender::setLayout(OFunique_ptr<Layout> lo)
{
    thread::MutexGuard guard (access_mutex);

    this->layout = OFmove(lo);
}



Layout*
Appender::getLayout()
{
    return layout.get();
}


} // namespace log4cplus
} // end namespace dcmtk