/*

 * Copyright (C) 2009 Google Inc. All rights reserved.

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 * modification, are permitted provided that the following conditions are

 * met:

 *

 *     * Redistributions of source code must retain the above copyright

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

 *     * 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.

 *     * Neither the name of Google Inc. nor the names of its

 * contributors may be used to endorse or promote products derived from

 * this software without specific prior written permission.

 *

 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND 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 THE COPYRIGHT

 * OWNER OR 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

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

 */

#include "config.h"

#include "ScriptState.h"

#include "Frame.h"

#include "Node.h"

#include "Page.h"

#include "ScriptController.h"

#include "V8HiddenPropertyName.h"

#include <v8.h>

#include <wtf/Assertions.h>

namespace WebCore {

ScriptState::ScriptState(v8::Handle<v8::Context> context)

    : m_context(v8::Persistent<v8::Context>::New(context))

{

    m_context.MakeWeak(this, &ScriptState::weakReferenceCallback);

}

ScriptState::~ScriptState()

{

    m_context.Dispose();

    m_context.Clear();

}

ScriptState* ScriptState::forContext(v8::Local<v8::Context> context)

{

    v8::Context::Scope contextScope(context);

    v8::Local<v8::Object> global = context->Global();

    // Skip proxy object. The proxy object will survive page navigation while we need

    // an object whose lifetime consides with that of the inspected context.

    global = v8::Local<v8::Object>::Cast(global->GetPrototype());

    v8::Handle<v8::String> key = V8HiddenPropertyName::scriptState();

    v8::Local<v8::Value> val = global->GetHiddenValue(key);

    if (!val.IsEmpty() && val->IsExternal())

        return static_cast<ScriptState*>(v8::External::Cast(*val)->Value());

    ScriptState* state = new ScriptState(context);

    global->SetHiddenValue(key, v8::External::New(state));

    return state;

}

ScriptState* ScriptState::current()

{

    v8::HandleScope handleScope;

    v8::Local<v8::Context> context = v8::Context::GetCurrent();

    if (context.IsEmpty()) {

        ASSERT_NOT_REACHED();

        return 0;

    }

    return ScriptState::forContext(context);

}

void ScriptState::weakReferenceCallback(v8::Persistent<v8::Value> object, void* parameter)

{

    ScriptState* scriptState = static_cast<ScriptState*>(parameter);

    delete scriptState;

}

ScriptState* mainWorldScriptState(Frame* frame)

{

    v8::HandleScope handleScope;

    V8Proxy* proxy = frame->script()->proxy();

    return ScriptState::forContext(proxy->mainWorldContext());

}

ScriptState* scriptStateFromNode(DOMWrapperWorld*, Node* node)

{

    // This should be never reached with V8 bindings (WebKit only uses it

    // for non-JS bindings)

    ASSERT_NOT_REACHED();

    return 0;

}

ScriptState* scriptStateFromPage(DOMWrapperWorld*, Page* page)

{

    // This should be only reached with V8 bindings from single process layout tests.

    return mainWorldScriptState(page->mainFrame());

}

}