windowsconsolelogger.hpp

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//==================================================================================================
/// \file
/// This header file is part of module \alib_alox of the \aliblong.
///
/// \emoji :copyright: 2013-2024 A-Worx GmbH, Germany.
/// Published under \ref mainpage_license "Boost Software License".
//==================================================================================================
#ifndef HPP_ALIB_LOX_WINDOWS_CONSOLE_LOGGER
#define HPP_ALIB_LOX_WINDOWS_CONSOLE_LOGGER 1
#pragma once
#include "alib/alox/textlogger/textlogger.hpp"
 
#if defined( _WIN32 ) || DOXYGEN
 
namespace alib {  namespace lox { namespace loggers {
 
//==================================================================================================
/// A logger that logs all messages to the standard output <em>cout</em>.
/// The name of the \e Logger defaults to "WINDOWS_CONSOLE".
///
/// \alox text logger escape sequences (see class \ref alib::lox::ESC "ESC")
/// are translated to Windows API calls (<em>SetConsoleTextAttribute</em>) which manipulates
/// colors the text output.
/// There is not 100% match between windows console capabilities and the definitions in
/// \ref alib::lox::ESC "ESC". Especially, ESC style attributes are ignored.
///
/// Foreground and background colors can be set to be either light/dark or dark/light. This improves
/// the readability of log output a lot and even allows reading if foreground and background colors
/// are the same (they then still differ). However, the right setting for this is dependent on
/// the color scheme of the final output device (window). To manipulate the right setting, see the
/// field #CFP and also configuration variable \ref alxcvALOX_CONSOLE_LIGHT_COLORS.
///
/// In the method #AcknowledgeLox, the default meta info string and color settings are changed
/// to fit this logger.
///
/// \note This class cannot enable the output console (which receives \alox log data) to support
///       the windows API call <em>SetConsoleTextAttribute</em>.
///       The opposite is right: this class should be used only if the output console supports such
///       calls.
//==================================================================================================
class WindowsConsoleLogger : public alib::lox::textlogger::TextLogger
{
    // #############################################################################################
    // Internals
    // #############################################################################################
    protected:
        /// The attributes that were set on the windows console at the time this object was created.
        WORD        originalConsoleAttributes;
 
    // #############################################################################################
    // public fields
    // #############################################################################################
    public:
 
        /// The code page that is used for the console log output. For possible values refer to
        /// \https{Microsoft documentation,msdn.microsoft.com/EN-US/library/windows/desktop/dd317756%28v=vs.85%29.aspx}
        ///
        /// This defaults to 65001, which is UTF-8 unicode encoding.
        ///
        /// This flag can be modified from outside any time. If the value is not equal to 0,
        /// the code page of the output console is set before each log output.
        ///
        /// The configuration variable \ref alxcvALOX_CODEPAGE is evaluated within the constructor of
        /// this class, to allow to modifying the codepage at run-time.
        UINT            CodePage                                                            =65001;
 
        /// @see \alib{lox::loggers;AnsiLogger::CFP}.
        textlogger::ColorfulLoggerParameters   CFP;
 
 
    // #############################################################################################
    // Constructor/destructor
    // #############################################################################################
    public:
        //==========================================================================================
        ///  Creates a WindowsConsoleLogger.
        /// @param name  (Optional) The name of the \e Logger, defaults to "WINDOWS_CONSOLE".
        //==========================================================================================
        ALIB_API
        explicit            WindowsConsoleLogger( const NString& name= nullptr  );
 
        //==========================================================================================
        /// Destructs a WindowsConsoleLogger
        //==========================================================================================
        virtual            ~WindowsConsoleLogger()                                                {}
 
 
    // #############################################################################################
    // Abstract method implementations
    // #############################################################################################
    protected:
        //==========================================================================================
        ///  The implementation of the abstract method of parent class TextLogger.
        ///  Logs messages to the basic output stream 'cout' and sets windows console colors
        ///  by invoking corresponding Windows API methods..
        ///
        /// @param domain      The <em>Log Domain</em>.
        /// @param verbosity   The verbosity. This has been checked to be active already on this
        ///                    stage and is provided to be able to be logged out only.
        /// @param msg         The log message.
        /// @param scope       Information about the scope of the <em>Log Statement</em>..
        /// @param lineNumber  The line number of a multi-line message, starting with 0. For
        ///                    single line messages this is -1.
        //==========================================================================================
        ALIB_API
        virtual void logText(  detail::Domain&     domain,
                               Verbosity         verbosity,
                               AString&          msg,
                               detail::ScopeInfo&  scope,
                               int               lineNumber);
 
        //==========================================================================================
        ///  Empty implementation, not needed for this class
        //==========================================================================================
        ALIB_API
        virtual void notifyMultiLineOp (lang::Phase )    {}
 
        //==========================================================================================
        /// Invokes parent method. Then reads and interprets configuration variable
        /// \ref alxcvALOX_CONSOLE_LIGHT_COLORS. Finally it is checked if variable
        /// \ref alxcvALOX_LOGGERNAME_FORMAT has priority of default values, and if yes, such
        /// values are overwritten to include ANSI color codes. These color codes are retrieved from
        /// resources named <c>"Var_D21A"</c>.
        ///
        /// @param lox     The \b %Lox to acknowledge insertion or removal
        /// @param op      The operation. Either \b ContainerOp::Insert or \b ContainerOp::Remove.
        //==========================================================================================
        ALIB_API
        virtual void AcknowledgeLox( detail::LoxImpl* lox, lang::ContainerOp op )          override;
 
 
 
}; // class WindowsConsoleLogger
 
}} // namespace alib[::lox::loggers]
 
/// Type alias in namespace \b alib.
using     WindowsConsoleLogger=     lox::loggers::WindowsConsoleLogger;
 
}  // namespace [alib]
 
#endif // defined( _WIN32 )
 
#endif // HPP_ALIB_LOX_WINDOWS_CONSOLE_LOGGER