#ifndef COMPILER_ERRORHANDLER_H_INCLUDED
#define COMPILER_ERRORHANDLER_H_INCLUDED

#include <string>

namespace Compiler
{
    struct TokenLoc;

    /// \brief Error handling
    ///
    /// This class collects errors and provides an interface for reporting them to the user.

    class ErrorHandler
    {
        int mWarnings;
        int mErrors;
        int mWarningsMode;
        bool mDowngradeErrors;

    protected:
        enum Type
        {
            WarningMessage,
            ErrorMessage
        };

    private:
        // mutators

        virtual void report(const std::string& message, const TokenLoc& loc, Type type) = 0;
        ///< Report error to the user.

        virtual void report(const std::string& message, Type type) = 0;
        ///< Report a file related error

    public:
        ErrorHandler();
        ///< constructor

        virtual ~ErrorHandler();
        ///< destructor

        bool isGood() const;
        ///< Was compiling successful?

        int countErrors() const;
        ///< Return number of errors

        int countWarnings() const;
        ///< Return number of warnings

        void warning(const std::string& message, const TokenLoc& loc);
        ///< Generate a warning message.

        void error(const std::string& message, const TokenLoc& loc);
        ///< Generate an error message.

        void endOfFile();
        ///< Generate an error message for an unexpected EOF.

        virtual void reset();
        ///< Remove all previous error/warning events

        void setWarningsMode(int mode);
        ///< // 0 ignore, 1 rate as warning, 2 rate as error

        /// Treat errors as warnings.
        void downgradeErrors(bool downgrade);
    };

    class ErrorDowngrade
    {
        ErrorHandler& mHandler;

        /// not implemented
        ErrorDowngrade(const ErrorDowngrade&);

        /// not implemented
        ErrorDowngrade& operator=(const ErrorDowngrade&);

    public:
        explicit ErrorDowngrade(ErrorHandler& handler);

        ~ErrorDowngrade();
    };
}

#endif
