/*

 * Copyright 2017 Google Inc.

 *

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

 * found in the LICENSE file.

 */

#ifndef Skottie_DEFINED

#define Skottie_DEFINED

#include "include/core/SkRefCnt.h"

#include "include/core/SkScalar.h"

#include "include/core/SkSize.h"

#include "include/core/SkString.h"

#include "include/core/SkTypes.h"

#include "modules/skresources/include/SkResources.h"

// TODO(kjlubick) update clients and then remove the following:

#include "include/core/SkFontMgr.h"  // IWYU pragma: keep

#include "modules/skottie/include/ExternalLayer.h"  // IWYU pragma: keep

#include "modules/skottie/include/SkottieProperty.h"  // IWYU pragma: keep

#include "modules/skottie/include/SlotManager.h"  // IWYU pragma: keep

#include <cstddef>

#include <cstdint>

#include <vector>

class SkCanvas;

class SkStream;

struct SkRect;

namespace sksg {

class InvalidationController;

class RenderNode;

} // namespace sksg

namespace SkShapers { class Factory; }

namespace skottie {

namespace internal { class Animator; }

using ImageAsset = skresources::ImageAsset;

using ResourceProvider = skresources::ResourceProvider;

/**

 * A Logger subclass can be used to receive Animation::Builder parsing errors and warnings.

 */

class SK_API Logger : public SkRefCnt {

public:

    enum class Level {

        kWarning,

        kError,

    };

    virtual void log(Level, const char message[], const char* json = nullptr) = 0;

};

// Evaluates AE expressions.

template <class T>

class SK_API ExpressionEvaluator : public SkRefCnt {

public:

    // Evaluate the expression at the current time.

    virtual T evaluate(float t) = 0;

};

/**

 * Creates ExpressionEvaluators to evaluate AE expressions and return the results.

 */

class SK_API ExpressionManager : public SkRefCnt {

public:

    virtual sk_sp<ExpressionEvaluator<float>> createNumberExpressionEvaluator(

        const char expression[]) = 0;

    virtual sk_sp<ExpressionEvaluator<SkString>> createStringExpressionEvaluator(

        const char expression[]) = 0;

    virtual sk_sp<ExpressionEvaluator<std::vector<float>>> createArrayExpressionEvaluator(

        const char expression[]) = 0;

};

/**

 * Interface for receiving AE composition markers at Animation build time.

 */

class SK_API MarkerObserver : public SkRefCnt {

public:

    // t0,t1 are in the Animation::seek() domain.

    virtual void onMarker(const char name[], float t0, float t1) = 0;

};

class SK_API Animation : public SkNVRefCnt<Animation> {

public:

    class SK_API Builder final {

    public:

        enum Flags : uint32_t {

            kDeferImageLoading   = 0x01, // Normally, all static image frames are resolved at

                                         // load time via ImageAsset::getFrame(0).  With this flag,

                                         // frames are only resolved when needed, at seek() time.

            kPreferEmbeddedFonts = 0x02, // Attempt to use the embedded fonts (glyph paths,

                                         // normally used as fallback) over native Skia typefaces.

        };

        explicit Builder(uint32_t flags = 0);

        Builder(const Builder&);

        Builder(Builder&&);

        ~Builder();

        struct Stats {

            float  fTotalLoadTimeMS  = 0, // Total animation instantiation time.

                   fJsonParseTimeMS  = 0, // Time spent building a JSON DOM.

                   fSceneParseTimeMS = 0; // Time spent constructing the animation scene graph.

            size_t fJsonSize         = 0, // Input JSON size.

                   fAnimatorCount    = 0; // Number of dynamically animated properties.

        };

        /**

         * Returns various animation build stats.

         *

         * @return Stats (see above).

         */

        const Stats& getStats() const { return fStats; }

        /**

         * Specify a loader for external resources (images, etc.).

         */

        Builder& setResourceProvider(sk_sp<ResourceProvider>);

        /**

         * Specify a font manager for loading animation fonts.

         */

        Builder& setFontManager(sk_sp<SkFontMgr>);

        /**

         * Specify a PropertyObserver to receive callbacks during parsing.

         *

         * See SkottieProperty.h for more details.

         *

         */

        Builder& setPropertyObserver(sk_sp<PropertyObserver>);

        /**

         * Register a Logger with this builder.

         */

        Builder& setLogger(sk_sp<Logger>);

        /**

         * Register a MarkerObserver with this builder.

         */

        Builder& setMarkerObserver(sk_sp<MarkerObserver>);

        /**

         * Register a precomp layer interceptor.

         * This allows substituting precomp layers with custom/externally managed content.

         */

        Builder& setPrecompInterceptor(sk_sp<PrecompInterceptor>);

        /**

         * Registers an ExpressionManager to evaluate AE expressions.

         * If unspecified, expressions in the animation JSON will be ignored.

         */

        Builder& setExpressionManager(sk_sp<ExpressionManager>);

        /**

         * Registers a factory to be used when shaping text.

         * If unspecified, text will be shaped with primitive shaping.

         * See //modules/skshaper/utils/FactoryHelpers.h

         */

        Builder& setTextShapingFactory(sk_sp<SkShapers::Factory>);

        /**

         * Animation factories.

         */

        sk_sp<Animation> make(SkStream*);

        sk_sp<Animation> make(const char* data, size_t length);

        sk_sp<Animation> makeFromFile(const char path[]);

        /**

         * Get handle for SlotManager after animation is built.

         */

        const sk_sp<SlotManager>& getSlotManager() const {return fSlotManager;}

    private:

        const uint32_t          fFlags;

        sk_sp<ResourceProvider>   fResourceProvider;

        sk_sp<SkFontMgr>          fFontMgr;

        sk_sp<PropertyObserver>   fPropertyObserver;

        sk_sp<Logger>             fLogger;

        sk_sp<MarkerObserver  >   fMarkerObserver;

        sk_sp<PrecompInterceptor> fPrecompInterceptor;

        sk_sp<ExpressionManager>  fExpressionManager;

        sk_sp<SkShapers::Factory> fShapingFactory;

        sk_sp<SlotManager>        fSlotManager;

        Stats                     fStats;

    };

    /**

     * Animation factories.

     *

     * Use the Builder helper above for more options/control.

     */

    static sk_sp<Animation> Make(const char* data, size_t length);

    static sk_sp<Animation> Make(SkStream*);

    static sk_sp<Animation> MakeFromFile(const char path[]);

    ~Animation();

    enum RenderFlag : uint32_t {

        // When rendering into a known transparent buffer, clients can pass

        // this flag to avoid some unnecessary compositing overhead for

        // animations using layer blend modes.

        kSkipTopLevelIsolation   = 0x01,

        // By default, content is clipped to the intrinsic animation

        // bounds (as determined by its size).  If this flag is set,

        // then the animation can draw outside of the bounds.

        kDisableTopLevelClipping = 0x02,

    };

    using RenderFlags = uint32_t;

    /**

     * Draws the current animation frame.

     *

     * It is undefined behavior to call render() on a newly created Animation

     * before specifying an initial frame via one of the seek() variants.

     *

     * @param canvas   destination canvas

     * @param dst      optional destination rect

     * @param flags    optional RenderFlags

     */

    void render(SkCanvas* canvas, const SkRect* dst = nullptr) const;

    void render(SkCanvas* canvas, const SkRect* dst, RenderFlags) const;

    /**

     * [Deprecated: use one of the other versions.]

     *

     * Updates the animation state for |t|.

     *

     * @param t   normalized [0..1] frame selector (0 -> first frame, 1 -> final frame)

     * @param ic  optional invalidation controller (dirty region tracking)

     *

     */

    void seek(SkScalar t, sksg::InvalidationController* ic = nullptr) {

        this->seekFrameTime(t * this->duration(), ic);

    }

    /**

     * Update the animation state to match |t|, specified as a frame index

     * i.e. relative to duration() * fps().

     *

     * Fractional values are allowed and meaningful - e.g.

     *

     *   0.0 -> first frame

     *   1.0 -> second frame

     *   0.5 -> halfway between first and second frame

     */

    void seekFrame(double t, sksg::InvalidationController* ic = nullptr);

    /** Update the animation state to match t, specifed in frame time

     *  i.e. relative to duration().

     */

    void seekFrameTime(double t, sksg::InvalidationController* = nullptr);

    /**

     * Returns the animation duration in seconds.

     */

    double duration() const { return fDuration; }

    /**

     * Returns the animation frame rate (frames / second).

     */

    double fps() const { return fFPS; }

    /**

     * Animation in point, in frame index units.

     */

    double inPoint()  const { return fInPoint;  }

    /**

     * Animation out point, in frame index units.

     */

    double outPoint() const { return fOutPoint; }

    const SkString& version() const { return fVersion; }

    const SkSize&      size() const { return fSize;    }

private:

    enum Flags : uint32_t {

        kRequiresTopLevelIsolation = 1 << 0, // Needs to draw into a layer due to layer blending.

    };

    Animation(sk_sp<sksg::RenderNode>,

              std::vector<sk_sp<internal::Animator>>&&,

              SkString ver, const SkSize& size,

              double inPoint, double outPoint, double duration, double fps, uint32_t flags);

    const sk_sp<sksg::RenderNode>                fSceneRoot;

    const std::vector<sk_sp<internal::Animator>> fAnimators;

    const SkString                               fVersion;

    const SkSize                                 fSize;

    const double                                 fInPoint,

                                                 fOutPoint,

                                                 fDuration,

                                                 fFPS;

    const uint32_t                               fFlags;

    using INHERITED = SkNVRefCnt<Animation>;

};

} // namespace skottie

#endif // Skottie_DEFINED