/*
 * Copyright 2016 Google Inc.
 *
 * Use of this source code is governed by a BSD-style license that can be
 * found in the LICENSE file.
 */

#include "gm/gm.h"
#include "include/core/SkCanvas.h"
#include "include/core/SkFont.h"
#include "include/core/SkFontTypes.h"
#include "include/core/SkImageFilter.h"
#include "include/core/SkPaint.h"
#include "include/core/SkPoint.h"
#include "include/core/SkRRect.h"
#include "include/core/SkRect.h"
#include "include/core/SkScalar.h"
#include "include/core/SkSize.h"
#include "include/core/SkString.h"
#include "include/core/SkTileMode.h"
#include "include/core/SkTypes.h"
#include "include/effects/SkImageFilters.h"
#include "include/private/SkTPin.h"
#include "src/core/SkRandom.h"
#include "tools/DecodeUtils.h"
#include "tools/fonts/FontToolUtils.h"
#include "tools/timer/TimeUtils.h"

#include <array>

static const SkScalar kBlurMax = 7.0f;
static const int kNumNodes = 30;
static const int kWidth = 512;
static const int kHeight = 512;
static const SkScalar kBlurAnimationDuration = 4.0f; // in secs

// This GM draws a lot of layers with animating BlurImageFilters
class AnimatedImageBlurs : public skiagm::GM {
public:
    AnimatedImageBlurs() : fLastTime(0.0f) {
        this->setBGColor(0xFFCCCCCC);
    }

protected:
    bool runAsBench() const override { return true; }

    SkString getName() const override { return SkString("animated-image-blurs"); }

    SkISize getISize() override { return SkISize::Make(kWidth, kHeight); }

    void onOnceBeforeDraw() override {
        for (int i = 0; i < kNumNodes; ++i) {
            fNodes[i].init(&fRand);
        }
    }

    void onDraw(SkCanvas* canvas) override {
        SkPaint paint;
        paint.setAntiAlias(true);

        for (int i = 0; i < kNumNodes; ++i) {
            SkPaint layerPaint;
            layerPaint.setImageFilter(SkImageFilters::Blur(fNodes[i].sigma(), fNodes[i].sigma(),
                                                           nullptr));

            canvas->saveLayer(nullptr, &layerPaint);
                // The rect is outset to block the circle case
                SkRect rect = SkRect::MakeLTRB(fNodes[i].pos().fX - fNodes[i].size()-0.5f,
                                               fNodes[i].pos().fY - fNodes[i].size()-0.5f,
                                               fNodes[i].pos().fX + fNodes[i].size()+0.5f,
                                               fNodes[i].pos().fY + fNodes[i].size()+0.5f);
                SkRRect rrect = SkRRect::MakeRectXY(rect, fNodes[i].size(), fNodes[i].size());
                canvas->drawRRect(rrect, paint);
            canvas->restore();
        }
    }

    bool onAnimate(double nanos) override {
        if (0.0f != fLastTime) {
            for (int i = 0; i < kNumNodes; ++i) {
                fNodes[i].update(nanos, fLastTime);
            }
        }

        fLastTime = 1e-9 * nanos;
        return true;
    }

private:
    class Node {
    public:
        Node()
            : fSize(0.0f)
            , fPos { 0.0f, 0.0f }
            , fDir { 1.0f, 0.0f }
            , fBlurOffset(0.0f)
            , fBlur(fBlurOffset)
            , fSpeed(0.0f) {
        }

        void init(SkRandom* rand) {
            fSize = rand->nextRangeF(10.0f, 60.f);
            fPos.fX = rand->nextRangeF(fSize, kWidth - fSize);
            fPos.fY = rand->nextRangeF(fSize, kHeight - fSize);
            fDir.fX = rand->nextRangeF(-1.0f, 1.0f);
            fDir.fY = SkScalarSqrt(1.0f - fDir.fX * fDir.fX);
            if (rand->nextBool()) {
                fDir.fY = -fDir.fY;
            }
            fBlurOffset = rand->nextRangeF(0.0f, kBlurMax);
            fBlur = fBlurOffset;
            fSpeed = rand->nextRangeF(20.0f, 60.0f);
        }

        void update(double nanos, SkScalar lastTime) {
            SkScalar deltaTime = 1e-9 * nanos - lastTime;

            fPos.fX += deltaTime * fSpeed * fDir.fX;
            fPos.fY += deltaTime * fSpeed * fDir.fY;
            if (fPos.fX >= kWidth || fPos.fX < 0.0f) {
                fPos.fX = SkTPin<SkScalar>(fPos.fX, 0.0f, kWidth);
                fDir.fX = -fDir.fX;
            }
            if (fPos.fY >= kHeight || fPos.fY < 0.0f) {
                fPos.fY = SkTPin<SkScalar>(fPos.fY, 0.0f, kHeight);
                fDir.fY = -fDir.fY;
            }

            fBlur = TimeUtils::PingPong(1e-9 * nanos, kBlurAnimationDuration, fBlurOffset, 0.0f, kBlurMax);
        }

        SkScalar sigma() const { return fBlur; }
        const SkPoint& pos() const { return fPos; }
        SkScalar size() const { return fSize; }

    private:
        SkScalar fSize;
        SkPoint  fPos;
        SkVector fDir;
        SkScalar fBlurOffset;
        SkScalar fBlur;
        SkScalar fSpeed;
    };

    std::array<Node, kNumNodes> fNodes;
    SkRandom fRand;
    SkScalar fLastTime;

    using INHERITED = GM;
};

// This GM draws an image with a tiled blur that animates from large to small sigmas
class AnimatedTiledImageBlur : public skiagm::GM {
static constexpr float kMaxBlurSigma = 250.f;
static constexpr float kAnimationDuration = 12.f; // seconds
public:
    AnimatedTiledImageBlur() : fBlurSigma(0.3f * kMaxBlurSigma) {
        this->setBGColor(0xFFCCCCCC);
    }

protected:
    bool runAsBench() const override { return true; }

    SkString getName() const override { return SkString("animated-tiled-image-blur"); }

    SkISize getISize() override { return SkISize::Make(530, 530); }

    void onOnceBeforeDraw() override {
        fImage = ToolUtils::GetResourceAsImage("images/mandrill_512.png");
    }

    void onDraw(SkCanvas* canvas) override {
        auto drawBlurredImage = [&](float tx, float ty, SkTileMode tileMode) {
            SkPaint paint;
            SkRect rect = SkRect::MakeIWH(250, 250);
            canvas->save();
            canvas->translate(tx, ty);
            paint.setImageFilter(SkImageFilters::Blur(fBlurSigma, fBlurSigma, tileMode,
                                                      nullptr, rect));
            canvas->drawImageRect(fImage, rect, SkFilterMode::kLinear, &paint);
            canvas->restore();
        };

        drawBlurredImage(10.f,  10.f,  SkTileMode::kDecal);
        drawBlurredImage(270.f, 10.f,  SkTileMode::kClamp);
        drawBlurredImage(10.f,  270.f, SkTileMode::kRepeat);
        drawBlurredImage(270.f, 270.f, SkTileMode::kMirror);
    }

    bool onAnimate(double nanos) override {
        fBlurSigma = TimeUtils::PingPong(1e-9 * nanos, kAnimationDuration,
                                         0.f, 0.0f, kMaxBlurSigma);
        return true;
    }

private:
    sk_sp<SkImage> fImage;
    SkScalar fBlurSigma;
};

class AnimatedBackdropBlur final : public skiagm::GM {
public:
    SkString getName() const override { return SkString("animated-backdrop-blur"); }

    SkISize getISize() override { return {512, 1024}; }

    void onOnceBeforeDraw() override {
        fFont = SkFont(ToolUtils::DefaultPortableTypeface(), 20);
        fImage = ToolUtils::GetResourceAsImage("images/color_wheel.png");
        const SkRect crop{0, 100, 512, 400};
        fFilter = SkImageFilters::Crop(crop, SkTileMode::kDecal,
                        SkImageFilters::Blur(30, 30,
                                SkImageFilters::Crop(crop, SkTileMode::kMirror, nullptr)));

        fLayerRec = SkCanvas::SaveLayerRec(nullptr, nullptr, fFilter.get(), 0);
    }

    void onDraw(SkCanvas* canvas) override {
        static constexpr const char* txts[] = {
            "Lorem ipsum dolor sit amet,",
            "consectetur adipiscing elit,",
            "sed do eiusmod tempor incididunt",
            "ut labore et dolore magna aliqua.",
            "",
            "",
            "Ut enim ad minim veniam,",
            "quis nostrud exercitation ullamco laboris",
            "nisi ut aliquip ex ea commodo consequat.",
            "",
            "",
            "Duis aute irure dolor in reprehenderit",
            "in voluptate velit esse cillum dolore",
            "eu fugiat nulla pariatur."
        };

        SkPaint paint;
        float voffset = fVOffset;
        for (const auto& txt : txts) {
            canvas->drawSimpleText(
                txt, strlen(txt), SkTextEncoding::kUTF8, 0, voffset, fFont, paint);
            voffset += fFont.getSize();
        }

        float dstHeight = fImage->height() * 128.f / fImage->width();
        canvas->drawImageRect(fImage.get(), SkRect::MakeXYWH(16.f, fVOffset, 128.f, dstHeight),
                              SkFilterMode::kLinear);

        canvas->saveLayer(fLayerRec);
        canvas->restore();
    }

    bool onAnimate(double nanos) override {
        fVOffset = TimeUtils::PingPong(nanos * 1e-9, 6, 0, 350, 0);

        return true;
    }

private:
    sk_sp<SkImageFilter>   fFilter;
    sk_sp<SkImage>         fImage;
    SkCanvas::SaveLayerRec fLayerRec;
    SkFont                 fFont;
    float                  fVOffset = 0;
};

//////////////////////////////////////////////////////////////////////////////

DEF_GM(return new AnimatedImageBlurs;)
DEF_GM(return new AnimatedTiledImageBlur;)
DEF_GM(return new AnimatedBackdropBlur;)