/*

 * Copyright 2005 Frerich Raabe <raabe@kde.org>

 * Copyright (C) 2006 Apple Computer, Inc.

 *

 * 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 THE AUTHOR ``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 THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,

 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT

 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,

 * DATA, OR 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 "XPathResult.h"

#if ENABLE(XPATH)

#include "EventListener.h"

#include "EventNames.h"

#include "EventTargetNode.h"

#include "ExceptionCode.h"

#include "XPathEvaluator.h"

namespace WebCore {

using namespace XPath;

class InvalidatingEventListener : public EventListener {

public:

    InvalidatingEventListener(XPathResult* result) : m_result(result) { }

    virtual void handleEvent(Event*, bool) { m_result->invalidateIteratorState(); }

private:

    XPathResult* m_result;

};

XPathResult::XPathResult(EventTargetNode* eventTarget, const Value& value)

    : m_value(value)

    , m_eventTarget(eventTarget)

{

    m_eventListener = new InvalidatingEventListener(this);

    m_eventTarget->addEventListener(EventNames::DOMSubtreeModifiedEvent, m_eventListener, false);

    switch (m_value.type()) {

        case Value::BooleanValue:

            m_resultType = BOOLEAN_TYPE;

            return;

        case Value::NumberValue:

            m_resultType = NUMBER_TYPE;

            return;

        case Value::StringValue:

            m_resultType = STRING_TYPE;

            return;

        case Value::NodeSetValue:

            m_resultType = UNORDERED_NODE_ITERATOR_TYPE;

            m_nodeSetPosition = 0;

            m_nodeSet = m_value.toNodeSet();

            m_invalidIteratorState = false;

            return;

    }

    ASSERT_NOT_REACHED();

}

XPathResult::~XPathResult()

{

    if (m_eventTarget)

        m_eventTarget->removeEventListener(EventNames::DOMSubtreeModifiedEvent, m_eventListener.get(), false);

}

void XPathResult::convertTo(unsigned short type, ExceptionCode& ec)

{

    switch (type) {

        case ANY_TYPE:

            break;

        case NUMBER_TYPE:

            m_resultType = type;

            m_value = m_value.toNumber();

            break;

        case STRING_TYPE:

            m_resultType = type;

            m_value = m_value.toString();

            break;

        case BOOLEAN_TYPE:

            m_resultType = type;

            m_value = m_value.toBoolean();

            break;

        case UNORDERED_NODE_ITERATOR_TYPE:

        case UNORDERED_NODE_SNAPSHOT_TYPE:

        case ANY_UNORDERED_NODE_TYPE:

        case FIRST_ORDERED_NODE_TYPE: // This is correct - singleNodeValue() will take care of ordering.

            if (!m_value.isNodeSet()) {

                ec = TYPE_ERR;

                return;

            }

            m_resultType = type;

            break;

        case ORDERED_NODE_ITERATOR_TYPE:

            if (!m_value.isNodeSet()) {

                ec = TYPE_ERR;

                return;

            }

            m_nodeSet.sort();

            m_resultType = type;

            break;

        case ORDERED_NODE_SNAPSHOT_TYPE:

            if (!m_value.isNodeSet()) {

                ec = TYPE_ERR;

                return;

            }

            m_value.toNodeSet().sort();

            m_resultType = type;

            break;

    }

}

unsigned short XPathResult::resultType() const

{

    return m_resultType;

}

double XPathResult::numberValue(ExceptionCode& ec) const

{

    if (resultType() != NUMBER_TYPE) {

        ec = TYPE_ERR;

        return 0.0;

    }

    return m_value.toNumber();

}

String XPathResult::stringValue(ExceptionCode& ec) const

{

    if (resultType() != STRING_TYPE) {

        ec = TYPE_ERR;

        return String();

    }

    return m_value.toString();

}

bool XPathResult::booleanValue(ExceptionCode& ec) const

{

    if (resultType() != BOOLEAN_TYPE) {

        ec = TYPE_ERR;

        return false;

    }

    return m_value.toBoolean();

}

Node* XPathResult::singleNodeValue(ExceptionCode& ec) const

{

    if (resultType() != ANY_UNORDERED_NODE_TYPE && resultType() != FIRST_ORDERED_NODE_TYPE) {

        ec = TYPE_ERR;

        return 0;

    }

    const NodeSet& nodes = m_value.toNodeSet();

    if (resultType() == FIRST_ORDERED_NODE_TYPE)

        return nodes.firstNode();

    else

        return nodes.anyNode();

}

void XPathResult::invalidateIteratorState()

{ 

    m_invalidIteratorState = true;

    ASSERT(m_eventTarget);

    ASSERT(m_eventListener);

    m_eventTarget->removeEventListener(EventNames::DOMSubtreeModifiedEvent, m_eventListener.get(), false);

    m_eventTarget = 0;

}

bool XPathResult::invalidIteratorState() const

{

    if (resultType() != UNORDERED_NODE_ITERATOR_TYPE && resultType() != ORDERED_NODE_ITERATOR_TYPE)

        return false;

    return m_invalidIteratorState;

}

unsigned long XPathResult::snapshotLength(ExceptionCode& ec) const

{

    if (resultType() != UNORDERED_NODE_SNAPSHOT_TYPE && resultType() != ORDERED_NODE_SNAPSHOT_TYPE) {

        ec = TYPE_ERR;

        return 0;

    }

    return m_value.toNodeSet().size();

}

Node* XPathResult::iterateNext(ExceptionCode& ec)

{

    if (resultType() != UNORDERED_NODE_ITERATOR_TYPE && resultType() != ORDERED_NODE_ITERATOR_TYPE) {

        ec = TYPE_ERR;

        return 0;

    }

    if (m_invalidIteratorState) {

        ec = INVALID_STATE_ERR;

        return 0;

    }

    if (m_nodeSetPosition + 1 > m_nodeSet.size())

        return 0;

    Node* node = m_nodeSet[m_nodeSetPosition];

    m_nodeSetPosition++;

    return node;

}

Node* XPathResult::snapshotItem(unsigned long index, ExceptionCode& ec)

{

    if (resultType() != UNORDERED_NODE_SNAPSHOT_TYPE && resultType() != ORDERED_NODE_SNAPSHOT_TYPE) {

        ec = TYPE_ERR;

        return 0;

    }

    const NodeSet& nodes = m_value.toNodeSet();

    if (index >= nodes.size())

        return 0;

    return nodes[index];

}

}

#endif // ENABLE(XPATH)