//
// Ascii.h
//
// Library: Foundation
// Package: Core
// Module:  Ascii
//
// Definition of the Ascii class.
//
// Copyright (c) 2010, Applied Informatics Software Engineering GmbH.
// and Contributors.
//
// SPDX-License-Identifier:	BSL-1.0
//


#ifndef Foundation_Ascii_INCLUDED
#define Foundation_Ascii_INCLUDED


#include "Poco/Foundation.h"


namespace Poco {


class Foundation_API Ascii
	/// This class contains enumerations and static
	/// utility functions for dealing with ASCII characters
	/// and their properties.
	///
	/// The classification functions will also work if
	/// non-ASCII character codes are passed to them,
	/// but classification will only check for
	/// ASCII characters.
	///
	/// This allows the classification methods to be used
	/// on the single bytes of a UTF-8 string, without
	/// causing assertions or inconsistent results (depending
	/// upon the current locale) on bytes outside the ASCII range,
	/// as may be produced by Ascii::isSpace(), etc.
{
public:
	enum CharacterProperties
		/// ASCII character properties.
	{
		ACP_CONTROL  = 0x0001,
		ACP_SPACE    = 0x0002,
		ACP_PUNCT    = 0x0004,
		ACP_DIGIT    = 0x0008,
		ACP_HEXDIGIT = 0x0010,
		ACP_ALPHA    = 0x0020,
		ACP_LOWER    = 0x0040,
		ACP_UPPER    = 0x0080,
		ACP_GRAPH    = 0x0100,
		ACP_PRINT    = 0x0200
	};
	
	static int properties(int ch);
		/// Return the ASCII character properties for the
		/// character with the given ASCII value.
		///
		/// If the character is outside the ASCII range
		/// (0 .. 127), 0 is returned.

	static bool hasSomeProperties(int ch, int properties);
		/// Returns true if the given character is
		/// within the ASCII range and has at least one of 
		/// the given properties.

	static bool hasProperties(int ch, int properties);
		/// Returns true if the given character is
		/// within the ASCII range and has all of 
		/// the given properties.

	static bool isAscii(int ch);
		/// Returns true iff the given character code is within
		/// the ASCII range (0 .. 127).
		
	static bool isSpace(int ch);
		/// Returns true iff the given character is a whitespace.
		
	static bool isDigit(int ch);
		/// Returns true iff the given character is a digit.

	static bool isHexDigit(int ch);
		/// Returns true iff the given character is a hexadecimal digit.
		
	static bool isPunct(int ch);
		/// Returns true iff the given character is a punctuation character.
		
	static bool isAlpha(int ch);
		/// Returns true iff the given character is an alphabetic character.	

	static bool isAlphaNumeric(int ch);
		/// Returns true iff the given character is an alphabetic character.	
		
	static bool isLower(int ch);
		/// Returns true iff the given character is a lowercase alphabetic
		/// character.
		
	static bool isUpper(int ch);
		/// Returns true iff the given character is an uppercase alphabetic
		/// character.
		
	static bool isPrintable(int ch);
		/// Returns true iff the given character is printable.

	static int toLower(int ch);
		/// If the given character is an uppercase character,
		/// return its lowercase counterpart, otherwise return
		/// the character.

	static int toUpper(int ch);
		/// If the given character is a lowercase character,
		/// return its uppercase counterpart, otherwise return
		/// the character.
		
private:
	static const int CHARACTER_PROPERTIES[128];
};


//
// inlines
//
inline int Ascii::properties(int ch)
{
	if (isAscii(ch)) 
		return CHARACTER_PROPERTIES[ch];
	else
		return 0;
}


inline bool Ascii::isAscii(int ch)
{
	return (static_cast<UInt32>(ch) & 0xFFFFFF80) == 0;
}


inline bool Ascii::hasProperties(int ch, int props)
{
	return (properties(ch) & props) == props;
}


inline bool Ascii::hasSomeProperties(int ch, int props)
{
	return (properties(ch) & props) != 0;
}


inline bool Ascii::isSpace(int ch)
{
	return hasProperties(ch, ACP_SPACE);
}


inline bool Ascii::isDigit(int ch)
{
	return hasProperties(ch, ACP_DIGIT);
}


inline bool Ascii::isHexDigit(int ch)
{
	return hasProperties(ch, ACP_HEXDIGIT);
}


inline bool Ascii::isPunct(int ch)
{
	return hasProperties(ch, ACP_PUNCT);
}


inline bool Ascii::isAlpha(int ch)
{
	return hasProperties(ch, ACP_ALPHA);
}


inline bool Ascii::isAlphaNumeric(int ch)
{
	return hasSomeProperties(ch, ACP_ALPHA | ACP_DIGIT);
}


inline bool Ascii::isLower(int ch)
{
	return hasProperties(ch, ACP_LOWER);
}


inline bool Ascii::isUpper(int ch)
{
	return hasProperties(ch, ACP_UPPER);
}


inline bool Ascii::isPrintable(int ch)
{
	return hasProperties(ch, ACP_PRINT);
}


inline int Ascii::toLower(int ch)
{
	if (isUpper(ch))
		return ch + 32;
	else
		return ch;
}


inline int Ascii::toUpper(int ch)
{
	if (isLower(ch))
		return ch - 32;
	else
		return ch;
}


} // namespace Poco


#endif // Foundation_Ascii_INCLUDED
