/*
 * Copyright (C) 2010, 2012 Apple 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 INC. 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 INC. 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.
 */

#ifndef MessageID_h
#define MessageID_h

namespace CoreIPC {

enum MessageClass {
    MessageClassInvalid = 0,

    // Messages sent by Core IPC.
    MessageClassCoreIPC,

    // Messages sent by the UI process to the web process.
    MessageClassAuthenticationManager,
    MessageClassCoordinatedLayerTreeHost,
    MessageClassDrawingArea,
    MessageClassWebApplicationCacheManager,
    MessageClassWebBatteryManagerProxy,
    MessageClassWebCookieManager,
    MessageClassWebDatabaseManager,
    MessageClassWebFullScreenManager,
    MessageClassWebGeolocationManagerProxy,
    MessageClassWebIconDatabaseProxy,
    MessageClassWebInspector,
    MessageClassWebKeyValueStorageManager,
    MessageClassWebMediaCacheManager,
    MessageClassWebNetworkInfoManagerProxy,
    MessageClassWebNotificationManager,
    MessageClassWebPage,
    MessageClassWebPageGroupProxy,
    MessageClassWebProcess,
    MessageClassWebResourceCacheManager,
    MessageClassEventDispatcher,
#if USE(SOUP)
    MessageClassWebSoupRequestManager,
#endif

    // Messages sent by the web process to the UI process.
    MessageClassCoordinatedLayerTreeHostProxy,
    MessageClassDownloadProxy,
    MessageClassDrawingAreaProxy,
    MessageClassWebApplicationCacheManagerProxy,
    MessageClassWebBatteryManager,
    MessageClassWebConnection,
    MessageClassWebContext,
    MessageClassWebContextLegacy,
    MessageClassWebCookieManagerProxy,
    MessageClassWebDatabaseManagerProxy,
    MessageClassWebFullScreenManagerProxy,
    MessageClassWebGeolocationManager,
    MessageClassWebIconDatabase,
    MessageClassWebInspectorProxy,
    MessageClassWebKeyValueStorageManagerProxy,
    MessageClassWebMediaCacheManagerProxy,
    MessageClassWebNetworkInfoManager,
    MessageClassWebNotificationManagerProxy,
    MessageClassWebPageProxy,
    MessageClassWebProcessProxy,
    MessageClassWebResourceCacheManagerProxy,
#if USE(SOUP)
    MessageClassWebSoupRequestManagerProxy,
#endif
    MessageClassWebVibrationProxy,
    MessageClassRemoteLayerTreeHost,

    // Messages sent to a WebConnection
    MessageClassWebConnectionLegacy,

    // Messages sent by the UI process to the plug-in process.
    MessageClassPluginProcess,

    // Messages sent by the plug-in process to the UI process.
    MessageClassPluginProcessProxy,

    // Messages sent by the web process to the plug-in process.
    MessageClassWebProcessConnection,
    MessageClassPluginControllerProxy,

    // Messages sent by the plug-in process to the web process.
    MessageClassPluginProcessConnection,
    MessageClassPluginProxy,

    // NPObject messages sent by both the plug-in process and the web process.
    MessageClassNPObjectMessageReceiver,

    // Messages sent by the UI process to the network process.
    MessageClassNetworkProcess,

    // Messages sent by the network process to the UI process.
    MessageClassNetworkProcessProxy,

    // Messages sent by the web process to the network process.
    MessageClassNetworkConnectionToWebProcess,
    MessageClassNetworkResourceLoader,

    // Messages sent by the network process to a web process.
    MessageClassNetworkProcessConnection,
    MessageClassWebResourceLoader,
    
#if ENABLE(SHARED_WORKER_PROCESS)
    // Messages sent by the UI process to the shared worker process.
    MessageClassSharedWorkerProcess,
#endif // ENABLE(SHARED_WORKER_PROCESS)

    // Messages sent by the shared worker process to the UI process.
    MessageClassSharedWorkerProcessProxy,
    
#if ENABLE(CUSTOM_PROTOCOLS)
    // Messages sent by the UI process to a web process (soon the network process).
    MessageClassCustomProtocolManager,

    // Messages sent by a web process (soon the network process) to the UI process.
    MessageClassCustomProtocolManagerProxy,
#endif
};

template<typename> struct MessageKindTraits { };


/*
    MessageID Layout (the most significant bit is reserved and therefore always zero)

    ---------
    | Flags | 7 bits
    |-------|
    | Class | 8 bits
    |-------|
    |  Msg  | 16 bits
    |  Kind |
    ---------
*/

class MessageID {
public:
    enum Flags {
        SyncMessage = 1 << 0,
        DispatchMessageWhenWaitingForSyncReply = 1 << 1,
    };

    MessageID()
        : m_messageID(0)
    {
    }

    template <typename EnumType>
    explicit MessageID(EnumType messageKind, unsigned char flags = 0)
        : m_messageID(stripMostSignificantBit(flags << 24 | (MessageKindTraits<EnumType>::messageClass) << 16 | messageKind))
    {
    }

    MessageID messageIDWithAddedFlags(unsigned char flags)
    {
        MessageID messageID;

        messageID.m_messageID = stripMostSignificantBit(m_messageID | (flags << 24));
        return messageID;
    }

    template <typename EnumType>
    EnumType get() const
    {
        ASSERT(getClass() == MessageKindTraits<EnumType>::messageClass);
        return static_cast<EnumType>(m_messageID & 0xffff);
    }

    template <MessageClass K>
    bool is() const
    {
        return getClass() == K;
    }
    
    template <typename EnumType>
    bool operator==(EnumType messageKind) const
    {
        return m_messageID == MessageID(messageKind).m_messageID;
    }

    static MessageID fromInt(unsigned i)
    {
        MessageID messageID;
        messageID.m_messageID = stripMostSignificantBit(i);
        
        return messageID;
    }
    
    unsigned toInt() const { return m_messageID; }

    bool shouldDispatchMessageWhenWaitingForSyncReply() const { return getFlags() & DispatchMessageWhenWaitingForSyncReply; }
    bool isSync() const { return getFlags() & SyncMessage; }

    MessageClass messageClass() const
    {
        return static_cast<MessageClass>(getClass());
    }

private:
    static inline unsigned stripMostSignificantBit(unsigned value)
    {
        return value & 0x7fffffff;
    }

    unsigned char getFlags() const { return (m_messageID & 0xff000000) >> 24; }
    unsigned char getClass() const { return (m_messageID & 0x00ff0000) >> 16; }

    unsigned m_messageID;
};

} // namespace CoreIPC
    
#endif // MessageID_h