//
// UTF8String.h
//
// Library: Foundation
// Package: Text
// Module:  UTF8String
//
// Definition of the UTF8 string functions.
//
// Copyright (c) 2007, Applied Informatics Software Engineering GmbH.
// and Contributors.
//
// SPDX-License-Identifier:	BSL-1.0
//


#ifndef Foundation_UTF8String_INCLUDED
#define Foundation_UTF8String_INCLUDED


#include "Poco/Foundation.h"


namespace Poco {


struct Foundation_API UTF8
	/// This class provides static methods that are UTF-8 capable variants
	/// of the same functions in Poco/String.h.
	///
	/// The various variants of icompare() provide case insensitive comparison
	/// for UTF-8 encoded strings.
	///
	/// toUpper(), toUpperInPlace(), toLower() and toLowerInPlace() provide
	/// Unicode-based character case transformation for UTF-8 encoded strings.
	///
	/// removeBOM() removes the UTF-8 Byte Order Mark sequence (0xEF, 0xBB, 0xBF)
	/// from the beginning of the given string, if it's there.
{
	enum NormalizationForm
		/// Normalization form for normalize().
	{
		NORMALIZATION_FORM_D,  /// Canonical Decomposition
		NORMALIZATION_FORM_C,  /// Canonical Decomposition, followed by Canonical Composition
		NORMALIZATION_FORM_KD, /// Compatibility Decomposition
		NORMALIZATION_FORM_KC  /// Compatibility Decomposition, followed by Canonical Composition
	};

	static int icompare(const std::string& str, std::string::size_type pos, std::string::size_type n, std::string::const_iterator it2, std::string::const_iterator end2);
	static int icompare(const std::string& str1, const std::string& str2);
	static int icompare(const std::string& str1, std::string::size_type n1, const std::string& str2, std::string::size_type n2);
	static int icompare(const std::string& str1, std::string::size_type n, const std::string& str2);
	static int icompare(const std::string& str1, std::string::size_type pos, std::string::size_type n, const std::string& str2);
	static int icompare(const std::string& str1, std::string::size_type pos1, std::string::size_type n1, const std::string& str2, std::string::size_type pos2, std::string::size_type n2);
	static int icompare(const std::string& str1, std::string::size_type pos1, std::string::size_type n, const std::string& str2, std::string::size_type pos2);
	static int icompare(const std::string& str, std::string::size_type pos, std::string::size_type n, const std::string::value_type* ptr);
	static int icompare(const std::string& str, std::string::size_type pos, const std::string::value_type* ptr);
	static int icompare(const std::string& str, const std::string::value_type* ptr);

	static std::string toUpper(const std::string& str);
	static std::string& toUpperInPlace(std::string& str);
	static std::string toLower(const std::string& str);
	static std::string& toLowerInPlace(std::string& str);

	static void removeBOM(std::string& str);
		/// Remove the UTF-8 Byte Order Mark sequence (0xEF, 0xBB, 0xBF)
		/// from the beginning of the string, if it's there.

	static std::string escape(const std::string& s, bool strictJSON = false);
		/// Escapes a string. Special characters like tab, backslash, ... are
		/// escaped. Unicode characters are escaped to \uxxxx.
		/// If strictJSON is true, \a and \v will be escaped to \\u0007 and \\u000B
		/// instead of \\a and \\v for strict JSON conformance.

	static std::string escape(const std::string::const_iterator& begin, const std::string::const_iterator& end, bool strictJSON = false, bool lowerCaseHex = false);
		/// Escapes a string. Special characters like tab, backslash, ... are
		/// escaped. Unicode characters are escaped to \uxxxx.
		/// If strictJSON is true, \a and \v will be escaped to \\u0007 and \\u000B
		/// instead of \\a and \\v for strict JSON conformance.

	static std::string unescape(const std::string& s);
		/// Creates an UTF8 string from a string that contains escaped characters.

	static std::string unescape(const std::string::const_iterator& begin, const std::string::const_iterator& end);
		/// Creates an UTF8 string from a string that contains escaped characters.

	static std::string normalize(const std::string& s, NormalizationForm form);
		/// Normalizes the given UTF8 string according to the given normalization form.
		/// Returns the normalized UTF8 string.

	static std::string normalize(const std::string::const_iterator& begin, const std::string::const_iterator& end, NormalizationForm form);
		/// Normalizes the given UTF8 string range according to the given normalization form.
		/// Returns the normalized UTF8 string.
};


} // namespace Poco


#endif // Foundation_UTF8String_INCLUDED