//

// SPDX-License-Identifier: BSD-3-Clause

// Copyright (c) Contributors to the OpenEXR Project.

//

#ifndef INCLUDED_IMF_CHANNEL_LIST_H

#define INCLUDED_IMF_CHANNEL_LIST_H

//-----------------------------------------------------------------------------

//

//  class Channel

//  class ChannelList

//

//-----------------------------------------------------------------------------

#include "ImfForward.h"

#include "ImfName.h"

#include "ImfPixelType.h"

#include <map>

#include <set>

#include <string>

OPENEXR_IMF_INTERNAL_NAMESPACE_HEADER_ENTER

struct IMF_EXPORT_TYPE Channel

{

    //------------------------------

    // Data type; see ImfPixelType.h

    //------------------------------

    PixelType type;

    //--------------------------------------------

    // Subsampling: pixel (x, y) is present in the

    // channel only if

    //

    //  x % xSampling == 0 && y % ySampling == 0

    //

    //--------------------------------------------

    int xSampling;

    int ySampling;

    //--------------------------------------------------------------

    // Hint to lossy compression methods that indicates whether

    // human perception of the quantity represented by this channel

    // is closer to linear or closer to logarithmic.  Compression

    // methods may optimize image quality by adjusting pixel data

    // quantization according to this hint.

    // For example, perception of red, green, blue and luminance is

    // approximately logarithmic; the difference between 0.1 and 0.2

    // is perceived to be roughly the same as the difference between

    // 1.0 and 2.0.  Perception of chroma coordinates tends to be

    // closer to linear than logarithmic; the difference between 0.1

    // and 0.2 is perceived to be roughly the same as the difference

    // between 1.0 and 1.1.

    //--------------------------------------------------------------

    bool pLinear;

    //------------

    // Constructor

    //------------

    IMF_EXPORT

    Channel (

        PixelType type      = HALF,

        int       xSampling = 1,

        int       ySampling = 1,

        bool      pLinear   = false);

    //------------

    // Operator ==

    //------------

    IMF_EXPORT

    bool operator== (const Channel& other) const;

};

class IMF_EXPORT_TYPE ChannelList

{

public:

    //--------------

    // Add a channel

    //--------------

    IMF_EXPORT

    void insert (const char name[], const Channel& channel);

    IMF_EXPORT

    void insert (const std::string& name, const Channel& channel);

    //------------------------------------------------------------------

    // Access to existing channels:

    //

    // [n]    Returns a reference to the channel with name n.

    //      If no channel with name n exists, an IEX_NAMESPACE::ArgExc

    //      is thrown.

    //

    // findChannel(n) Returns a pointer to the channel with name n,

    //      or 0 if no channel with name n exists.

    //

    //------------------------------------------------------------------

    IMF_EXPORT

    Channel& operator[] (const char name[]);

    IMF_EXPORT

    const Channel& operator[] (const char name[]) const;

    IMF_EXPORT

    Channel& operator[] (const std::string& name);

    IMF_EXPORT

    const Channel& operator[] (const std::string& name) const;

    IMF_EXPORT

    Channel* findChannel (const char name[]);

    IMF_EXPORT

    const Channel* findChannel (const char name[]) const;

    IMF_EXPORT

    Channel* findChannel (const std::string& name);

    IMF_EXPORT

    const Channel* findChannel (const std::string& name) const;

    //-------------------------------------------

    // Iterator-style access to existing channels

    //-------------------------------------------

    typedef std::map<Name, Channel> ChannelMap;

    class Iterator;

    class ConstIterator;

    IMF_EXPORT

    Iterator begin ();

    IMF_EXPORT

    ConstIterator begin () const;

    IMF_EXPORT

    Iterator end ();

    IMF_EXPORT

    ConstIterator end () const;

    IMF_EXPORT

    Iterator find (const char name[]);

    IMF_EXPORT

    ConstIterator find (const char name[]) const;

    IMF_EXPORT

    Iterator find (const std::string& name);

    IMF_EXPORT

    ConstIterator find (const std::string& name) const;

    //-----------------------------------------------------------------

    // Support for image layers:

    //

    // In an image file with many channels it is sometimes useful to

    // group the channels into "layers", that is, into sets of channels

    // that logically belong together.  Grouping channels into layers

    // is done using a naming convention:  channel C in layer L is

    // called "L.C".

    //

    // For example, a computer graphic image may contain separate

    // R, G and B channels for light that originated at each of

    // several different virtual light sources.  The channels in

    // this image might be called "light1.R", "light1.G", "light1.B",

    // "light2.R", "light2.G", "light2.B", etc.

    //

    // Note that this naming convention allows layers to be nested;

    // for example, "light1.specular.R" identifies the "R" channel

    // in the "specular" sub-layer of layer "light1".

    //

    // Channel names that don't contain a "." or that contain a

    // "." only at the beginning or at the end are not considered

    // to be part of any layer.

    //

    // layers(lns)    sorts the channels in this ChannelList

    //        into layers and stores the names of

    //        all layers, sorted alphabetically,

    //        into string set lns.

    //

    // channelsInLayer(ln,f,l)  stores a pair of iterators in f and l

    //        such that the loop

    //

    //        for (ConstIterator i = f; i != l; ++i)

    //           ...

    //

    //        iterates over all channels in layer ln.

    //        channelsInLayer (ln, l, p) calls

    //        channelsWithPrefix (ln + ".", l, p).

    //

    //-----------------------------------------------------------------

    IMF_EXPORT

    void layers (std::set<std::string>& layerNames) const;

    IMF_EXPORT

    void channelsInLayer (

        const std::string& layerName, Iterator& first, Iterator& last);

    IMF_EXPORT

    void channelsInLayer (

        const std::string& layerName,

        ConstIterator&     first,

        ConstIterator&     last) const;

    //-------------------------------------------------------------------

    // Find all channels whose name begins with a given prefix:

    //

    // channelsWithPrefix(p,f,l) stores a pair of iterators in f and l

    // such that the following loop iterates over all channels whose name

    // begins with string p:

    //

    //    for (ConstIterator i = f; i != l; ++i)

    //        ...

    //

    //-------------------------------------------------------------------

    IMF_EXPORT

    void

    channelsWithPrefix (const char prefix[], Iterator& first, Iterator& last);

    IMF_EXPORT

    void channelsWithPrefix (

        const char prefix[], ConstIterator& first, ConstIterator& last) const;

    IMF_EXPORT

    void channelsWithPrefix (

        const std::string& prefix, Iterator& first, Iterator& last);

    IMF_EXPORT

    void channelsWithPrefix (

        const std::string& prefix,

        ConstIterator&     first,

        ConstIterator&     last) const;

    //------------

    // Operator ==

    //------------

    IMF_EXPORT

    bool operator== (const ChannelList& other) const;

private:

    ChannelMap _map;

};

//----------

// Iterators

//----------

class IMF_EXPORT_TYPE ChannelList::Iterator

{

public:

    IMF_EXPORT

    Iterator ();

    IMF_EXPORT

    Iterator (const ChannelList::ChannelMap::iterator& i);

    IMF_EXPORT

    Iterator& operator++ ();

    IMF_EXPORT

    Iterator operator++ (int);

    IMF_EXPORT

    const char* name () const;

    IMF_EXPORT

    Channel& channel () const;

private:

    friend class ChannelList::ConstIterator;

    ChannelList::ChannelMap::iterator _i;

};

class IMF_EXPORT_TYPE ChannelList::ConstIterator

{

public:

    IMF_EXPORT

    ConstIterator ();

    IMF_EXPORT

    ConstIterator (const ChannelList::ChannelMap::const_iterator& i);

    IMF_EXPORT

    ConstIterator (const ChannelList::Iterator& other);

    IMF_EXPORT

    ConstIterator& operator++ ();

    IMF_EXPORT

    ConstIterator operator++ (int);

    IMF_EXPORT

    const char* name () const;

    IMF_EXPORT

    const Channel& channel () const;

private:

    friend bool operator== (const ConstIterator&, const ConstIterator&);

    friend bool operator!= (const ConstIterator&, const ConstIterator&);

    ChannelList::ChannelMap::const_iterator _i;

};

//-----------------

// Inline Functions

//-----------------

inline ChannelList::Iterator::Iterator () : _i ()

{

    // empty

}

inline ChannelList::Iterator::Iterator (

    const ChannelList::ChannelMap::iterator& i)

    : _i (i)

{

    // empty

}

inline ChannelList::Iterator&

ChannelList::Iterator::operator++ ()

{

    ++_i;

    return *this;

}

inline ChannelList::Iterator

ChannelList::Iterator::operator++ (int)

{

    Iterator tmp = *this;

    ++_i;

    return tmp;

}

inline const char*

ChannelList::Iterator::name () const

{

    return *_i->first;

}

inline Channel&

ChannelList::Iterator::channel () const

{

    return _i->second;

}

inline ChannelList::ConstIterator::ConstIterator () : _i ()

{

    // empty

}

inline ChannelList::ConstIterator::ConstIterator (

    const ChannelList::ChannelMap::const_iterator& i)

    : _i (i)

{

    // empty

}

inline ChannelList::ConstIterator::ConstIterator (

    const ChannelList::Iterator& other)

    : _i (other._i)

{

    // empty

}

inline ChannelList::ConstIterator&

ChannelList::ConstIterator::operator++ ()

{

    ++_i;

    return *this;

}

inline ChannelList::ConstIterator

ChannelList::ConstIterator::operator++ (int)

{

    ConstIterator tmp = *this;

    ++_i;

    return tmp;

}

inline const char*

ChannelList::ConstIterator::name () const

{

    return *_i->first;

}

inline const Channel&

ChannelList::ConstIterator::channel () const

{

    return _i->second;

}

inline bool

operator== (

    const ChannelList::ConstIterator& x, const ChannelList::ConstIterator& y)

{

    return x._i == y._i;

}

inline bool

operator!= (

    const ChannelList::ConstIterator& x, const ChannelList::ConstIterator& y)

{

    return !(x == y);

}

OPENEXR_IMF_INTERNAL_NAMESPACE_HEADER_EXIT

#endif