/*

 * Copyright 2024 Google LLC

 *

 * Use of this source code is governed by a BSD-style license that can be

 * found in the LICENSE file.

 */

#ifndef skgpu_graphite_precompile_PrecompileBase_DEFINED

#define skgpu_graphite_precompile_PrecompileBase_DEFINED

#include "include/core/SkRefCnt.h"

#include "include/core/SkSpan.h"

namespace skgpu::graphite {

class KeyContext;

class PaintParamsKeyBuilder;

class PipelineDataGatherer;

class PrecompileBasePriv;

/** \class PrecompileBase

    This is the base class for all the objects that can be attached to PaintOptions.

*/

class SK_API PrecompileBase : public SkRefCnt {

public:

    enum class Type {

        kBlender,

        kColorFilter,

        kImageFilter,

        kMaskFilter,

        kShader,

    };

    Type type() const { return fType; }

    // Provides access to functions that aren't part of the public API.

    PrecompileBasePriv priv();

    const PrecompileBasePriv priv() const;  // NOLINT(readability-const-return-type)

protected:

    PrecompileBase(Type type) : fType(type) {}

    virtual int numIntrinsicCombinations() const { return 1; }

    virtual int numChildCombinations() const { return 1; }

    /** This call returns the number of combinations generated from this object and its childen.

        @return       number of precompilation combinations generated by this object

    */

    int numCombinations() const {

        return this->numIntrinsicCombinations() * this->numChildCombinations();

    }

    virtual void addToKey(const KeyContext&,

                          PaintParamsKeyBuilder*,

                          PipelineDataGatherer*,

                          int desiredCombination) const = 0;

    // This returns the desired option along with the child options.

    template<typename T>

    static std::pair<sk_sp<T>, int> SelectOption(SkSpan<const sk_sp<T>> options,

                                                 int desiredOption);

    // In general, derived classes should use AddToKey to select the desired child option from

    // a span and then have it added to the key with its reduced/nested child option.

    template<typename T>

    static void AddToKey(const KeyContext&,

                         PaintParamsKeyBuilder*,

                         PipelineDataGatherer*,

                         SkSpan<const sk_sp<T>> options,

                         int desiredOption);

private:

    friend class PrecompileBasePriv;

    friend class PaintOptions;          // for access to SelectOption

    friend class PrecompileBlenderList; // ""

    Type fType;

};

} // namespace skgpu::graphite

#endif // skgpu_graphite_precompile_PrecompileBase_DEFINED