/*

 * Copyright (C) 2006, 2007, 2008 Apple Inc. All rights reserved.

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions

 * are met:

 * 1. Redistributions of source code must retain the above copyright

 *    notice, this list of conditions and the following disclaimer.

 * 2. Redistributions in binary form must reproduce the above copyright

 *    notice, this list of conditions and the following disclaimer in the

 *    documentation and/or other materials provided with the distribution.

 *

 * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY

 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE

 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR

 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE COMPUTER, INC. OR

 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,

 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,

 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY

 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT

 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE

 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 

 */

#include "config.h"

#include "TextDocument.h"

#include "DecodedDataDocumentParser.h"

#include "Element.h"

#include "HTMLNames.h"

#include "HTMLViewSourceDocument.h"

#include "SegmentedString.h"

#include "Text.h"

using namespace std;

namespace WebCore {

using namespace HTMLNames;

// FIXME: TextDocumentParser could just be an HTMLDocumentParser

// which started the Tokenizer in the PlainText state.

class TextDocumentParser : public DecodedDataDocumentParser {

public:

    TextDocumentParser(Document*);

    virtual ~TextDocumentParser();

    TextDocumentParser(HTMLViewSourceDocument*);

private:

    virtual void insert(const SegmentedString&);

    virtual void append(const SegmentedString&);

    virtual void finish();

    virtual bool finishWasCalled();

    inline void checkBuffer(int len = 10)

    {

        if ((m_dest - m_buffer) > m_size - len) {

            // Enlarge buffer

            int newSize = std::max(m_size * 2, m_size + len);

            int oldOffset = m_dest - m_buffer;

            m_buffer = static_cast<UChar*>(fastRealloc(m_buffer, newSize * sizeof(UChar)));

            m_dest = m_buffer + oldOffset;

            m_size = newSize;

        }

    }

private:

    Element* m_preElement;

    bool m_skipLF;

    int m_size;

    UChar* m_buffer;

    UChar* m_dest;

};

TextDocumentParser::TextDocumentParser(Document* document)

    : DecodedDataDocumentParser(document)

    , m_preElement(0)

    , m_skipLF(false)

{    

    // Allocate buffer

    m_size = 254;

    m_buffer = static_cast<UChar*>(fastMalloc(sizeof(UChar) * m_size));

    m_dest = m_buffer;

}    

TextDocumentParser::TextDocumentParser(HTMLViewSourceDocument* document)

    : DecodedDataDocumentParser(document, true)

    , m_preElement(0)

    , m_skipLF(false)

{    

    // Allocate buffer

    m_size = 254;

    m_buffer = static_cast<UChar*>(fastMalloc(sizeof(UChar) * m_size));

    m_dest = m_buffer;

}

TextDocumentParser::~TextDocumentParser()

{

    // finish() should have been called to prevent any leaks

    ASSERT(!m_buffer);

}

void TextDocumentParser::insert(const SegmentedString&)

{

    ASSERT_NOT_REACHED();

}

void TextDocumentParser::append(const SegmentedString& s)

{

    ExceptionCode ec;

    m_dest = m_buffer;

    SegmentedString str = s;

    while (!str.isEmpty()) {

        UChar c = *str;

        if (c == '\r') {

            *m_dest++ = '\n';

            // possibly skip an LF in the case of an CRLF sequence

            m_skipLF = true;

        } else if (c == '\n') {

            if (!m_skipLF)

                *m_dest++ = c;

            else

                m_skipLF = false;

        } else {

            *m_dest++ = c;

            m_skipLF = false;

        }

        str.advance();

        // Maybe enlarge the buffer

        checkBuffer();

    }

    if (!m_preElement && !inViewSourceMode()) {

        RefPtr<Element> rootElement = document()->createElement(htmlTag, false);

        document()->appendChild(rootElement, ec);

        RefPtr<Element> body = document()->createElement(bodyTag, false);

        rootElement->appendChild(body, ec);

        RefPtr<Element> preElement = document()->createElement(preTag, false);

        preElement->setAttribute("style", "word-wrap: break-word; white-space: pre-wrap;", ec);

        body->appendChild(preElement, ec);

        m_preElement = preElement.get();

    } 

    String string = String(m_buffer, m_dest - m_buffer);

    if (inViewSourceMode()) {

        static_cast<HTMLViewSourceDocument*>(document())->addViewSourceText(string);

        return;

    }

    unsigned charsLeft = string.length();

    while (charsLeft) {

        // split large text to nodes of manageable size

        RefPtr<Text> text = Text::createWithLengthLimit(document(), string, charsLeft);

        m_preElement->appendChild(text, ec);

    }

}

void TextDocumentParser::finish()

{

    if (!m_preElement)

        append(SegmentedString()); // Create document structure for an empty text document.

    m_preElement = 0;

    fastFree(m_buffer);

    m_buffer = 0;

    m_dest = 0;

    // FIXME: Should this call finishParsing even if m_parserStopped is true?

    // See equivalent implementation in RawDataDocumentParser.

    document()->finishedParsing();

}

bool TextDocumentParser::finishWasCalled()

{

    // finish() always calls document()->finishedParsing() so we'll be deleted

    // after finish().

    return false;

}

TextDocument::TextDocument(Frame* frame, const KURL& url)

    : HTMLDocument(frame, url)

{

}

DocumentParser* TextDocument::createParser()

{

    return new TextDocumentParser(this);

}

DocumentParser* createTextDocumentParser(HTMLViewSourceDocument* document)

{

    return new TextDocumentParser(document);

}

}