Source/modules/webmidi/MIDIAccessPromise.cpp

/*
 * Copyright (C) 2013 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:
 *
 *     * 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
 * (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 "modules/webmidi/MIDIAccessPromise.h"

#include "core/dom/DOMError.h"
#include "modules/webmidi/MIDIAccess.h"
#include "modules/webmidi/MIDIErrorCallback.h"
#include "modules/webmidi/MIDISuccessCallback.h"

namespace WebCore {

PassRefPtr<MIDIAccessPromise> MIDIAccessPromise::create(ExecutionContext* context, const Dictionary& options)
{
    RefPtr<MIDIAccessPromise> midiAccessPromise(adoptRef(new MIDIAccessPromise(context, options)));
    midiAccessPromise->suspendIfNeeded();
    return midiAccessPromise.release();
}

MIDIAccessPromise::MIDIAccessPromise(ExecutionContext* context, const Dictionary& options)
    : ActiveDOMObject(context)
    , m_state(Pending)
    , m_options(adoptPtr(new MIDIOptions(options)))
{
    ScriptWrappable::init(this);
}

MIDIAccessPromise::~MIDIAccessPromise()
{
    stop();
}

bool MIDIAccessPromise::hasPendingActivity() const
{
    return !!m_access && m_state != Accepted && m_state != Rejected;
}

void MIDIAccessPromise::stop()
{
    m_state = Invoked;
    if (!!m_access)
        m_access->stop();
    clear();
}

void MIDIAccessPromise::fulfill()
{
    if (m_state == Pending) {
        if (m_successCallback) {
            m_state = Invoked;
            ASSERT(m_access);
            m_successCallback->handleEvent(m_access.get(), m_options->sysex);
            clear();
        } else {
            m_state = Accepted;
        }
    }
}

void MIDIAccessPromise::reject(PassRefPtr<DOMError> error)
{
    if (m_state == Pending) {
        if (m_errorCallback) {
            m_state = Invoked;
            m_errorCallback->handleEvent(error.get());
            clear();
        } else {
            m_state = Rejected;
            m_error = error;
        }
    }
}

void MIDIAccessPromise::then(PassOwnPtr<MIDISuccessCallback> successCallback, PassOwnPtr<MIDIErrorCallback> errorCallback)
{
    // Lazily request access.
    if (!m_access)
        m_access = MIDIAccess::create(executionContext(), this);

    switch (m_state) {
    case Accepted:
        m_state = Invoked;
        successCallback->handleEvent(m_access.get(), m_options->sysex);
        clear();
        break;
    case Rejected:
        m_state = Invoked;
        errorCallback->handleEvent(m_error.get());
        clear();
        break;
    case Pending:
        m_successCallback = successCallback;
        m_errorCallback = errorCallback;
        break;
    case Invoked:
        break;
    default:
        ASSERT_NOT_REACHED();
    }
}

void MIDIAccessPromise::clear()
{
    ASSERT(m_state == Invoked);
    m_access.clear();
    m_error.clear();
    m_options.clear();
    m_successCallback.clear();
    m_errorCallback.clear();
}

} // namespace WebCore