/*
 * Copyright (C) 2007 David Smith (catfish.man@gmail.com)
 * Copyright (C) 2007, 2008, 2011, 2012 Apple Inc. All rights reserved.
 *
 * 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., 59 Temple Place - Suite 330,
 * Boston, MA 02111-1307, USA.
 */

#include "config.h"
#include "SpaceSplitString.h"

#include "HTMLParserIdioms.h"
#include <wtf/ASCIICType.h>
#include <wtf/HashMap.h>
#include <wtf/text/AtomicStringHash.h>
#include <wtf/text/StringBuilder.h>

using namespace WTF;

namespace WebCore {

template <typename CharacterType>
static inline bool hasNonASCIIOrUpper(const CharacterType* characters, unsigned length)
{
    bool hasUpper = false;
    CharacterType ored = 0;
    for (unsigned i = 0; i < length; i++) {
        CharacterType c = characters[i];
        hasUpper |= isASCIIUpper(c);
        ored |= c;
    }
    return hasUpper || (ored & ~0x7F);
}

static inline bool hasNonASCIIOrUpper(const String& string)
{
    unsigned length = string.length();

    if (string.is8Bit())
        return hasNonASCIIOrUpper(string.characters8(), length);
    return hasNonASCIIOrUpper(string.characters16(), length);
}

template <typename CharacterType, typename TokenProcessor>
static inline void tokenizeSpaceSplitString(TokenProcessor& tokenProcessor, const CharacterType* characters, unsigned length)
{
    unsigned start = 0;
    while (true) {
        while (start < length && isHTMLSpace(characters[start]))
            ++start;
        if (start >= length)
            break;
        unsigned end = start + 1;
        while (end < length && isNotHTMLSpace(characters[end]))
            ++end;

        if (!tokenProcessor.processToken(characters + start, end - start))
            return;

        start = end + 1;
    }
}

class AppendTokenToVectorTokenProcessor {
public:
    AppendTokenToVectorTokenProcessor(Vector<AtomicString, 4>& vector) : m_vector(vector) { }

    template <typename CharacterType>
    bool processToken(const CharacterType* characters, unsigned length)
    {
        m_vector.append(AtomicString(characters, length));
        return true;
    }
private:
    Vector<AtomicString, 4>& m_vector;
};

void SpaceSplitStringData::createVector(const String& string)
{
    unsigned length = string.length();

    AppendTokenToVectorTokenProcessor tokenProcessor(m_vector);
    if (string.is8Bit()) {
        tokenizeSpaceSplitString(tokenProcessor, string.characters8(), length);
        return;
    }

    tokenizeSpaceSplitString(tokenProcessor, string.characters16(), length);
}

bool SpaceSplitStringData::containsAll(SpaceSplitStringData& other)
{
    if (this == &other)
        return true;

    size_t thisSize = m_vector.size();
    size_t otherSize = other.m_vector.size();
    for (size_t i = 0; i < otherSize; ++i) {
        const AtomicString& name = other.m_vector[i];
        size_t j;
        for (j = 0; j < thisSize; ++j) {
            if (m_vector[j] == name)
                break;
        }
        if (j == thisSize)
            return false;
    }
    return true;
}

void SpaceSplitStringData::add(const AtomicString& string)
{
    ASSERT(hasOneRef());
    ASSERT(!contains(string));
    m_vector.append(string);
}

void SpaceSplitStringData::remove(unsigned index)
{
    ASSERT(hasOneRef());
    m_vector.remove(index);
}

void SpaceSplitString::add(const AtomicString& string)
{
    // FIXME: add() does not allow duplicates but createVector() does.
    if (contains(string))
        return;
    ensureUnique();
    if (m_data)
        m_data->add(string);
}

bool SpaceSplitString::remove(const AtomicString& string)
{
    if (!m_data)
        return false;
    unsigned i = 0;
    bool changed = false;
    while (i < m_data->size()) {
        if ((*m_data)[i] == string) {
            if (!changed)
                ensureUnique();
            m_data->remove(i);
            changed = true;
            continue;
        }
        ++i;
    }
    return changed;
}

typedef HashMap<AtomicString, SpaceSplitStringData*> SpaceSplitStringDataMap;

static SpaceSplitStringDataMap& sharedDataMap()
{
    DEFINE_STATIC_LOCAL(SpaceSplitStringDataMap, map, ());
    return map;
}

void SpaceSplitString::set(const AtomicString& inputString, bool shouldFoldCase)
{
    if (inputString.isNull()) {
        clear();
        return;
    }

    String string(inputString.string());
    if (shouldFoldCase && hasNonASCIIOrUpper(string))
        string = string.foldCase();

    m_data = SpaceSplitStringData::create(string);
}

class TokenIsEqualToCStringTokenProcessor {
public:
    TokenIsEqualToCStringTokenProcessor(const char* referenceString, unsigned referenceStringLength)
        : m_referenceString(referenceString)
        , m_referenceStringLength(referenceStringLength)
        , m_referenceStringWasFound(false)
    {
    }

    template <typename CharacterType>
    bool processToken(const CharacterType* characters, unsigned length)
    {
        if (length == m_referenceStringLength && equal(characters, reinterpret_cast<const LChar*>(m_referenceString), length)) {
            m_referenceStringWasFound = true;
            return false;
        }
        return true;
    }

    bool referenceStringWasFound() const { return m_referenceStringWasFound; }

private:
    const char* m_referenceString;
    unsigned m_referenceStringLength;
    bool m_referenceStringWasFound;
};

bool SpaceSplitString::spaceSplitStringContainsValue(const String& inputString, const char* value, unsigned valueLength, bool shouldFoldCase)
{
    if (inputString.isNull())
        return false;

    String string = inputString;
    if (shouldFoldCase && hasNonASCIIOrUpper(string))
        string = string.foldCase();

    TokenIsEqualToCStringTokenProcessor tokenProcessor(value, valueLength);
    unsigned length = string.length();
    if (string.is8Bit())
        tokenizeSpaceSplitString(tokenProcessor, string.characters8(), length);
    else
        tokenizeSpaceSplitString(tokenProcessor, string.characters16(), length);
    return tokenProcessor.referenceStringWasFound();
}

SpaceSplitStringData::~SpaceSplitStringData()
{
    if (!m_keyString.isNull())
        sharedDataMap().remove(m_keyString);
}

PassRefPtr<SpaceSplitStringData> SpaceSplitStringData::create(const AtomicString& string)
{
    SpaceSplitStringData*& data = sharedDataMap().add(string, 0).iterator->value;
    if (!data) {
        data = new SpaceSplitStringData(string);
        return adoptRef(data);
    }
    return data;
}

PassRefPtr<SpaceSplitStringData> SpaceSplitStringData::createUnique(const SpaceSplitStringData& other)
{
    return adoptRef(new SpaceSplitStringData(other));
}

SpaceSplitStringData::SpaceSplitStringData(const AtomicString& string)
    : m_keyString(string)
{
    ASSERT(!string.isNull());
    createVector(string);
}

SpaceSplitStringData::SpaceSplitStringData(const SpaceSplitStringData& other)
    : RefCounted<SpaceSplitStringData>()
    , m_vector(other.m_vector)
{
    // Note that we don't copy m_keyString to indicate to the destructor that there's nothing
    // to be removed from the sharedDataMap().
}

} // namespace WebCore