Source/WebCore/bindings/v8/IDBBindingUtilities.cpp

/*
 * Copyright (C) 2010 Google 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 AND ITS CONTRIBUTORS "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 OR ITS CONTRIBUTORS 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 "IDBBindingUtilities.h"

#if ENABLE(INDEXED_DATABASE)

#include "IDBDatabaseException.h"
#include "IDBKey.h"
#include "IDBKeyPath.h"
#include "SerializedScriptValue.h"
#include "V8Binding.h"
#include "V8IDBKey.h"
#include <wtf/Vector.h>

namespace WebCore {

PassRefPtr<IDBKey> createIDBKeyFromValue(v8::Handle<v8::Value> value)
{
    if (value->IsNull())
        return IDBKey::createNull();
    if (value->IsNumber())
        return IDBKey::createNumber(value->NumberValue());
    if (value->IsString())
        return IDBKey::createString(v8ValueToWebCoreString(value));
    if (value->IsDate())
        return IDBKey::createDate(value->NumberValue());

    return 0; // Signals type error.
}

namespace {

template<typename T>
bool getValueFrom(T indexOrName, v8::Handle<v8::Value>& v8Value)
{
    v8::Local<v8::Object> object = v8Value->ToObject();
    if (!object->Has(indexOrName))
        return false;
    v8Value = object->Get(indexOrName);
    return true;
}

template<typename T>
bool setValue(v8::Handle<v8::Value>& v8Object, T indexOrName, const v8::Handle<v8::Value>& v8Value)
{
    v8::Local<v8::Object> object = v8Object->ToObject();
    ASSERT(!object->Has(indexOrName));
    return object->Set(indexOrName, v8Value);
}

bool get(v8::Handle<v8::Value>& object, const IDBKeyPathElement& keyPathElement)
{
    switch (keyPathElement.type) {
    case IDBKeyPathElement::IsIndexed:
        return object->IsArray() && getValueFrom(keyPathElement.index, object);
    case IDBKeyPathElement::IsNamed:
        return object->IsObject() && getValueFrom(v8String(keyPathElement.identifier), object);
    default:
        ASSERT_NOT_REACHED();
    }
    return false;
}

bool set(v8::Handle<v8::Value>& object, const IDBKeyPathElement& keyPathElement, const v8::Handle<v8::Value>& v8Value)
{
    switch (keyPathElement.type) {
    case IDBKeyPathElement::IsIndexed:
        return object->IsArray() && setValue(object, keyPathElement.index, v8Value);
    case IDBKeyPathElement::IsNamed:
        return object->IsObject() && setValue(object, v8String(keyPathElement.identifier), v8Value);
    default:
        ASSERT_NOT_REACHED();
    }
    return false;
}

class LocalContext {
public:
    LocalContext()
        : m_context(v8::Context::New())
    {
        m_context->Enter();
    }

    ~LocalContext()
    {
        m_context->Exit();
        m_context.Dispose();
    }

private:
    v8::HandleScope m_scope;
    v8::Persistent<v8::Context> m_context;
};

v8::Handle<v8::Value> getNthValueOnKeyPath(v8::Handle<v8::Value>& rootValue, const Vector<IDBKeyPathElement>& keyPathElements, size_t index)
{
    v8::Handle<v8::Value> currentValue(rootValue);

    ASSERT(index <= keyPathElements.size());
    for (size_t i = 0; i < index; ++i) {
        if (!get(currentValue, keyPathElements[i]))
            return v8::Handle<v8::Value>();
    }

    return currentValue;
}

} // anonymous namespace

PassRefPtr<IDBKey> createIDBKeyFromSerializedValueAndKeyPath(PassRefPtr<SerializedScriptValue> value, const Vector<IDBKeyPathElement>& keyPath)
{
    LocalContext localContext;
    v8::Handle<v8::Value> v8Value(value->deserialize());
    v8::Handle<v8::Value> v8Key(getNthValueOnKeyPath(v8Value, keyPath, keyPath.size()));
    if (v8Key.IsEmpty())
        return 0;
    return createIDBKeyFromValue(v8Key);
}

PassRefPtr<SerializedScriptValue> injectIDBKeyIntoSerializedValue(PassRefPtr<IDBKey> key, PassRefPtr<SerializedScriptValue> value, const Vector<IDBKeyPathElement>& keyPath)
{
    LocalContext localContext;
    if (!keyPath.size())
        return 0;

    v8::Handle<v8::Value> v8Value(value->deserialize());
    v8::Handle<v8::Value> parent(getNthValueOnKeyPath(v8Value, keyPath, keyPath.size() - 1));
    if (parent.IsEmpty())
        return 0;

    if (!set(parent, keyPath.last(), toV8(key.get())))
        return 0;

    return SerializedScriptValue::create(v8Value);
}

} // namespace WebCore

#endif