/*

    This file is part of the KDE libraries

    Copyright (C) 2004, 2005, 2006 Apple Computer

    This library is free software; you can redistribute it and/or

    modify it under the terms of the GNU Library General Public

    License as published by the Free Software Foundation; either

    version 2 of the License, or (at your option) any later version.

    This library is distributed in the hope that it will be useful,

    but WITHOUT ANY WARRANTY; without even the implied warranty of

    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

    Library General Public License for more details.

    You should have received a copy of the GNU Library General Public License

    along with this library; see the file COPYING.LIB.  If not, write to

    the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,

    Boston, MA 02110-1301, USA.

*/

#ifndef SegmentedString_h

#define SegmentedString_h

#include "DeprecatedValueList.h"

#include "PlatformString.h"

namespace WebCore {

class SegmentedString;

class SegmentedSubstring {

private:

    friend class SegmentedString;

    SegmentedSubstring() : m_length(0), m_current(0), m_excludeLineNumbers(false) {}

    SegmentedSubstring(const String& str) : m_string(str), m_length(str.length()), m_excludeLineNumbers(false) {

        m_current = m_length == 0 ? 0 : m_string.characters();

    }

    SegmentedSubstring(const UChar* str, int length) : m_length(length), m_current(length == 0 ? 0 : str), m_excludeLineNumbers(false) {}

    void clear() { m_length = 0; m_current = 0; }

    bool excludeLineNumbers() const { return m_excludeLineNumbers; }

    void setExcludeLineNumbers() { m_excludeLineNumbers = true; }

    void appendTo(String& str) const {

        if (m_string.characters() == m_current) {

            if (str.isEmpty())

                str = m_string;

            else

                str.append(m_string);

        } else {

            str.append(String(m_current, m_length));

        }

    }

    String m_string;

    int m_length;

    const UChar* m_current;

    bool m_excludeLineNumbers;

};

class SegmentedString {

public:

    SegmentedString()

        : m_pushedChar1(0), m_pushedChar2(0), m_currentChar(0), m_composite(false) {}

    SegmentedString(const UChar* str, int length) : m_pushedChar1(0), m_pushedChar2(0)

        , m_currentString(str, length), m_currentChar(m_currentString.m_current), m_composite(false) {}

    SegmentedString(const String& str)

        : m_pushedChar1(0), m_pushedChar2(0), m_currentString(str)

        , m_currentChar(m_currentString.m_current), m_composite(false) {}

    SegmentedString(const SegmentedString&);

    const SegmentedString& operator=(const SegmentedString&);

    void clear();

    void append(const SegmentedString &);

    void prepend(const SegmentedString &);

    bool excludeLineNumbers() const { return m_currentString.excludeLineNumbers(); }

    void setExcludeLineNumbers();

    void push(UChar c) {

        if (!m_pushedChar1) {

            m_pushedChar1 = c;

            m_currentChar = m_pushedChar1 ? &m_pushedChar1 : m_currentString.m_current;

        } else {

            ASSERT(!m_pushedChar2);

            m_pushedChar2 = c;

        }

    }

    bool isEmpty() const { return !current(); }

    unsigned length() const;

    void advance(int* lineNumber = 0) {

        if (m_pushedChar1) {

            m_pushedChar1 = m_pushedChar2;

            m_pushedChar2 = 0;

        } else if (m_currentString.m_current) {

            if (*m_currentString.m_current++ == '\n' && lineNumber && !m_currentString.excludeLineNumbers())

                *lineNumber = *lineNumber + 1;

            if (--m_currentString.m_length == 0)

                advanceSubstring();

        }

        m_currentChar = m_pushedChar1 ? &m_pushedChar1 : m_currentString.m_current;

    }

    bool escaped() const { return m_pushedChar1; }

    String toString() const;

    const UChar& operator*() const { return *current(); }

    const UChar* operator->() const { return current(); }

private:

    void append(const SegmentedSubstring &);

    void prepend(const SegmentedSubstring &);

    void advanceSubstring();

    const UChar* current() const { return m_currentChar; }

    UChar m_pushedChar1;

    UChar m_pushedChar2;

    SegmentedSubstring m_currentString;

    const UChar* m_currentChar;

    DeprecatedValueList<SegmentedSubstring> m_substrings;

    bool m_composite;

};

}

#endif