/*
  ==============================================================================

   This file is part of the JUCE 6 technical preview.
   Copyright (c) 2017 - ROLI Ltd.

   You may use this code under the terms of the GPL v3
   (see www.gnu.org/licenses).

   For this technical preview, this file is not subject to commercial licensing.

   JUCE IS PROVIDED "AS IS" WITHOUT ANY WARRANTY, AND ALL WARRANTIES, WHETHER
   EXPRESSED OR IMPLIED, INCLUDING MERCHANTABILITY AND FITNESS FOR PURPOSE, ARE
   DISCLAIMED.

  ==============================================================================
*/

struct _XDisplay;

namespace juce
{

typedef ::_XDisplay* XDisplay;

typedef unsigned long AtomType;
typedef unsigned long WindowType;


//==============================================================================
class XWindowSystem :  public DeletedAtShutdown
{
public:
    XDisplay displayRef() noexcept;
    XDisplay displayUnref() noexcept;

    JUCE_DECLARE_SINGLETON (XWindowSystem, false)

private:
    XDisplay display = {};
    Atomic<int> displayCount;

    XWindowSystem() noexcept;
    ~XWindowSystem() noexcept;

    void initialiseXDisplay() noexcept;
    void destroyXDisplay() noexcept;
};

//==============================================================================
/** Creates and holds a reference to the X display.

    @tags{GUI}
*/
struct ScopedXDisplay
{
    ScopedXDisplay();
    ~ScopedXDisplay();

    const XDisplay display;
};

//==============================================================================
/** A handy class that uses XLockDisplay and XUnlockDisplay to lock the X server
    using RAII (Only available in Linux!).

    @tags{GUI}
*/
class ScopedXLock
{
public:
    /** Creating a ScopedXLock object locks the X display.
        This uses XLockDisplay() to grab the display that JUCE is using.
    */
    ScopedXLock (XDisplay);

    /** Deleting a ScopedXLock object unlocks the X display.
        This calls XUnlockDisplay() to release the lock.
    */
    ~ScopedXLock();

private:
    // defined in juce_linux_X11.h
    XDisplay display;
};

//==============================================================================
struct Atoms
{
    Atoms (XDisplay);

    enum ProtocolItems
    {
        TAKE_FOCUS = 0,
        DELETE_WINDOW = 1,
        PING = 2
    };

    AtomType protocols, protocolList[3], changeState, state, userTime,
             activeWin, pid, windowType, windowState,
             XdndAware, XdndEnter, XdndLeave, XdndPosition, XdndStatus,
             XdndDrop, XdndFinished, XdndSelection, XdndTypeList, XdndActionList,
             XdndActionDescription, XdndActionCopy, XdndActionPrivate,
             XembedMsgType, XembedInfo,
             allowedActions[5],
             allowedMimeTypes[4];

    static const unsigned long DndVersion;

    static AtomType getIfExists (XDisplay, const char* name);
    static AtomType getCreating (XDisplay, const char* name);

    static String getName (XDisplay, AtomType);

    static bool isMimeTypeFile (XDisplay, AtomType);
};

//==============================================================================
struct GetXProperty
{
    GetXProperty (XDisplay, WindowType, AtomType,
                  long offset, long length, bool shouldDelete,
                  AtomType requestedType);

    ~GetXProperty();

    bool success;
    unsigned char* data = nullptr;
    unsigned long numItems, bytesLeft;
    AtomType actualType;
    int actualFormat;
};

//==============================================================================
enum
{
    maxXEmbedVersionToSupport = 0
};

enum
{
    XEMBED_MAPPED  = (1<<0)
};

enum
{
    XEMBED_EMBEDDED_NOTIFY        = 0,
    XEMBED_WINDOW_ACTIVATE        = 1,
    XEMBED_WINDOW_DEACTIVATE      = 2,
    XEMBED_REQUEST_FOCUS          = 3,
    XEMBED_FOCUS_IN               = 4,
    XEMBED_FOCUS_OUT              = 5,
    XEMBED_FOCUS_NEXT             = 6,
    XEMBED_FOCUS_PREV             = 7,
    XEMBED_MODALITY_ON            = 10,
    XEMBED_MODALITY_OFF           = 11,
    XEMBED_REGISTER_ACCELERATOR   = 12,
    XEMBED_UNREGISTER_ACCELERATOR = 13,
    XEMBED_ACTIVATE_ACCELERATOR   = 14
};

enum
{
    XEMBED_FOCUS_CURRENT = 0,
    XEMBED_FOCUS_FIRST   = 1,
    XEMBED_FOCUS_LAST    = 2
};

} // namespace juce