// -*- C++ -*-
// Module:  Log4CPLUS
// File:    configurator.h
// Created: 3/2003
// Author:  Tad E. Smith
//
//
// Copyright 2003-2015 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.

/** @file */

#ifndef LOG4CPLUS_CONFIGURATOR_HEADER_
#define LOG4CPLUS_CONFIGURATOR_HEADER_

#include <log4cplus/config.hxx>

#if defined (LOG4CPLUS_HAVE_PRAGMA_ONCE)
#pragma once
#endif

#include <log4cplus/appender.h>
#include <log4cplus/logger.h>
#include <log4cplus/helpers/pointer.h>
#include <log4cplus/helpers/property.h>

#include <map>


namespace log4cplus
{
    class Hierarchy;


    /**
     * Provides configuration from an external file.  See configure() for
     * the expected format.
     *
     * <em>All option values admit variable substitution.</em> For
     * example, if <code>userhome</code> environment property is set to
     * <code>/home/xyz</code> and the File option is set to the string
     * <code>${userhome}/test.log</code>, then File option will be
     * interpreted as the string <code>/home/xyz/test.log</code>.
     *
     * The syntax of variable substitution is similar to that of UNIX
     * shells. The string between an opening <b>&quot;${&quot;</b> and
     * closing <b>&quot;}&quot;</b> is interpreted as a key. Its value is
     * searched in the environment properties.  The corresponding value replaces
     * the ${variableName} sequence.
     *
     * Configuration files also recognize <code>include
     * <i>file.properties</i></code> directive that allow composing
     * configuration from multiple files. There is no cyclic includes
     * detection mechanism to stop unbound recursion.
     */
    class LOG4CPLUS_EXPORT PropertyConfigurator
    {
    public:
        enum PCFlags
        {
            fRecursiveExpansion   = (1 << 0)
            , fShadowEnvironment  = (1 << 1)
            , fAllowEmptyVars     = (1 << 2)

            // These encoding related options occupy 2 bits of the flags
            // and are mutually exclusive. These flags are synchronized with
            // PFlags in Properties.

            , fEncodingShift      = 3
            , fEncodingMask       = 0x3
            , fUnspecEncoding     = (0 << fEncodingShift)
#if defined (LOG4CPLUS_HAVE_CODECVT_UTF8_FACET) && defined (UNICODE)
            , fUTF8               = (1 << fEncodingShift)
#endif
#if (defined (LOG4CPLUS_HAVE_CODECVT_UTF16_FACET) || defined (_WIN32)) \
    && defined (UNICODE)
            , fUTF16              = (2 << fEncodingShift)
#endif
#if defined (LOG4CPLUS_HAVE_CODECVT_UTF32_FACET) && defined (UNICODE)
            , fUTF32              = (3 << fEncodingShift)
#endif
        };

        // ctor and dtor
        PropertyConfigurator(const log4cplus::tstring& propertyFile,
            Hierarchy& h = Logger::getDefaultHierarchy(), unsigned flags = 0);
        PropertyConfigurator(const log4cplus::helpers::Properties& props,
            Hierarchy& h = Logger::getDefaultHierarchy(), unsigned flags = 0);
        PropertyConfigurator(log4cplus::tistream& propertyStream,
            Hierarchy& h = Logger::getDefaultHierarchy(), unsigned flags = 0);
        virtual ~PropertyConfigurator();

        /**
         * This method eliminates the need to create a temporary
         * <code>PropertyConfigurator</code> to configure log4cplus.
         * It is equivalent to the following:<br>
         * <code>
         * PropertyConfigurator config("filename");
         * config.configure();
         * </code>
         */
        static void doConfigure(const log4cplus::tstring& configFilename,
            Hierarchy& h = Logger::getDefaultHierarchy(), unsigned flags = 0);

        /**
         * Read configuration from a file. <b>The existing configuration is
         * not cleared nor reset.</b> If you require a different behavior,
         * then call {@link Hierarchy::resetConfiguration
         * resetConfiguration} method before calling
         * <code>doConfigure</code>.
         *
         * The configuration file consists of statements in the format
         * <code>key=value</code>. The syntax of different configuration
         * elements are discussed below.
         *
         * <h3>Appender configuration</h3>
         *
         * Appender configuration syntax is:
         * <pre>
         * # For appender named <i>appenderName</i>, set its class.
         * # Note: The appender name can contain dots.
         * log4cplus.appender.appenderName=fully.qualified.name.of.appender.class
         *
         * # Set appender specific options.
         * log4cplus.appender.appenderName.option1=value1
         * ...
         * log4cplus.appender.appenderName.optionN=valueN
         * </pre>
         *
         * For each named appender you can configure its {@link Layout}. The
         * syntax for configuring an appender's layout is:
         * <pre>
         * log4cplus.appender.appenderName.layout=fully.qualified.name.of.layout.class
         * log4cplus.appender.appenderName.layout.option1=value1
         * ....
         * log4cplus.appender.appenderName.layout.optionN=valueN
         * </pre>
         *
         * <h3>Configuring loggers</h3>
         *
         * The syntax for configuring the root logger is:
         * <pre>
         * log4cplus.rootLogger=[LogLevel], appenderName, appenderName, ...
         * </pre>
         *
         * This syntax means that an optional <em>LogLevel value</em> can
         * be supplied followed by appender names separated by commas.
         *
         * The LogLevel value can consist of the string values FATAL,
         * ERROR, WARN, INFO, DEBUG or a <em>custom LogLevel</em> value.
         *
         * If a LogLevel value is specified, then the root LogLevel is set
         * to the corresponding LogLevel.  If no LogLevel value is specified,
         * then the root LogLevel remains untouched.
         *
         * The root logger can be assigned multiple appenders.
         *
         * Each <i>appenderName</i> (separated by commas) will be added to
         * the root logger. The named appender is defined using the
         * appender syntax defined above.
         *
         * For non-root loggers the syntax is almost the same:
         * <pre>
         * log4cplus.logger.logger_name=[LogLevel|INHERITED], appenderName, appenderName, ...
         * </pre>
         *
         * The meaning of the optional LogLevel value is discussed above
         * in relation to the root logger. In addition however, the value
         * INHERITED can be specified meaning that the named logger should
         * inherit its LogLevel from the logger hierarchy.
         *
         * By default loggers inherit their LogLevel from the
         * hierarchy.  However, if you set the LogLevel of a logger and
         * later decide that that logger should inherit its LogLevel, then
         * you should specify INHERITED as the value for the LogLevel value.
         *
         * Similar to the root logger syntax, each <i>appenderName</i>
         * (separated by commas) will be attached to the named logger.
         *
         * See the <a href="../../../../manual.html#additivity">appender
         * additivity rule</a> in the user manual for the meaning of the
         * <code>additivity</code> flag.
         *
         * The user can override any of the {@link
         * Hierarchy#disable} family of methods by setting the a key
         * "log4cplus.disableOverride" to <code>true</code> or any value other
         * than false. As in <pre>log4cplus.disableOverride=true </pre>
         *
         * <h3>Example</h3>
         *
         * An example configuration is given below.
         *
         * <pre>
         *
         * # Set options for appender named "A1".
         * # Appender "A1" will be a SyslogAppender
         * log4cplus.appender.A1=log4cplus::SyslogAppender
         *
         * # The syslog daemon resides on www.abc.net
         * log4cplus.appender.A1.SyslogHost=www.abc.net
         *
         * # A1's layout is a PatternLayout, using the conversion pattern
         * # <b>%r %-5p %c{2} %M.%L %x - %m\n</b>. Thus, the log output will
         * # include # the relative time since the start of the application in
         * # milliseconds, followed by the LogLevel of the log request,
         * # followed by the two rightmost components of the logger name,
         * # followed by the callers method name, followed by the line number,
         * # the nested disgnostic context and finally the message itself.
         * # Refer to the documentation of {@link PatternLayout} for further information
         * # on the syntax of the ConversionPattern key.
         * log4cplus.appender.A1.layout=log4cplus::PatternLayout
         * log4cplus.appender.A1.layout.ConversionPattern=%-4r %-5p %c{2} %M.%L %x - %m\n
         *
         * # Set options for appender named "A2"
         * # A2 should be a RollingFileAppender, with maximum file size of 10 MB
         * # using at most one backup file. A2's layout is TTCC, using the
         * # ISO8061 date format with context printing enabled.
         * log4cplus.appender.A2=log4cplus::RollingFileAppender
         * log4cplus.appender.A2.MaxFileSize=10MB
         * log4cplus.appender.A2.MaxBackupIndex=1
         * log4cplus.appender.A2.layout=log4cplus::TTCCLayout
         * log4cplus.appender.A2.layout.ContextPrinting=true
         * log4cplus.appender.A2.layout.DateFormat=ISO8601
         *
         * # Root logger set to DEBUG using the A2 appender defined above.
         * log4cplus.rootLogger=DEBUG, A2
         *
         * # Logger definitions:
         * # The SECURITY logger inherits is LogLevel from root. However, it's output
         * # will go to A1 appender defined above. It's additivity is non-cumulative.
         * log4cplus.logger.SECURITY=INHERIT, A1
         * log4cplus.additivity.SECURITY=false
         *
         * # Only warnings or above will be logged for the logger "SECURITY.access".
         * # Output will go to A1.
         * log4cplus.logger.SECURITY.access=WARN
         *
         *
         * # The logger "class.of.the.day" inherits its LogLevel from the
         * # logger hierarchy.  Output will go to the appender's of the root
         * # logger, A2 in this case.
         * log4cplus.logger.class.of.the.day=INHERIT
         * </pre>
         *
         * Refer to the <b>setOption</b> method in each Appender and
         * Layout for class specific options.
         *
         * Use the <code>#</code> character at the beginning of a line
         * for comments.
         */
        virtual void configure();

        /**
         * \return The return value is reference to Properties
         * container of properties with the <code>"log4cplus."</code>
         * prefix removed and references to other properties and/or
         * environment variables expanded.
         */
        log4cplus::helpers::Properties const & getProperties () const;

        /**
         * \return The return value is a reference to log4cplus::tstring
         * containing filename of properties source file. It will be
         * string "UNAVAILABLE" if the PropertyConfigurator instance has been
         * constructed using one of the other constructors that do not take
         * filename as parameter.
         */
        log4cplus::tstring const & getPropertyFilename () const;

    protected:
      // Methods
        void init();  // called by the ctor
        void reconfigure();
        void replaceEnvironVariables();
        void configureLoggers();
        void configureLogger(log4cplus::Logger logger, const log4cplus::tstring& config);
        void configureAppenders();
        void configureAdditivity();

        virtual Logger getLogger(const log4cplus::tstring& name);
        virtual void addAppender(Logger &logger, log4cplus::SharedAppenderPtr& appender);

      // Types
        typedef std::map<log4cplus::tstring, log4cplus::SharedAppenderPtr> AppenderMap;

      // Data
        Hierarchy& h;
        log4cplus::tstring propertyFilename;
        log4cplus::helpers::Properties properties;
        AppenderMap appenders;
        unsigned flags;

    private:
      // Disable copy
        PropertyConfigurator(const PropertyConfigurator&);
        PropertyConfigurator& operator=(PropertyConfigurator&);
    };



    /**
     * Use this class to quickly configure the package. For file based
     * configuration see PropertyConfigurator. BasicConfigurator
     * automatically attaches ConsoleAppender to
     * <code>rootLogger</code>, with output going to standard output,
     * using DEBUG LogLevel value. The additional parameter
     * logToStdErr may redirect the output to standard error.
     */
    class LOG4CPLUS_EXPORT BasicConfigurator : public PropertyConfigurator {
    public:
      // ctor and dtor
        BasicConfigurator(Hierarchy& h = Logger::getDefaultHierarchy(),
            bool logToStdErr = false);
        virtual ~BasicConfigurator();

        /**
         * This method eliminates the need to create a temporary
         * <code>BasicConfigurator</code> object to configure log4cplus.
         * It is equivalent to the following:<br>
         * <code><pre>
         * BasicConfigurator config;
         * config.configure();
         * </pre></code>
         */
        static void doConfigure(Hierarchy& h = Logger::getDefaultHierarchy(),
            bool logToStdErr = false);

        //! Property name for disable override.
        static log4cplus::tstring const DISABLE_OVERRIDE_KEY;

    private:
      // Disable copy
        BasicConfigurator(const BasicConfigurator&);
        BasicConfigurator& operator=(BasicConfigurator&);
    };


#if !defined(LOG4CPLUS_SINGLE_THREADED)
    // Forward Declarations
    class ConfigurationWatchDogThread;


    class LOG4CPLUS_EXPORT ConfigureAndWatchThread {
    public:
      // ctor and dtor
        ConfigureAndWatchThread(const log4cplus::tstring& propertyFile,
                                unsigned int millis = 60 * 1000);
        virtual ~ConfigureAndWatchThread();

    private:
      // Disallow copying of instances of this class
       ConfigureAndWatchThread(const ConfigureAndWatchThread&);
       ConfigureAndWatchThread& operator=(const ConfigureAndWatchThread&);

      // Data
       ConfigurationWatchDogThread * watchDogThread;
    };
#endif

} // end namespace log4cplus

#endif // LOG4CPLUS_CONFIGURATOR_HEADER_
