/*
 * Copyright (C) 2021 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package androidx.constraintlayout.core.state;

import androidx.annotation.NonNull;
import androidx.annotation.RestrictTo;
import androidx.constraintlayout.core.motion.CustomVariable;
import androidx.constraintlayout.core.motion.Motion;
import androidx.constraintlayout.core.motion.MotionWidget;
import androidx.constraintlayout.core.motion.key.MotionKeyAttributes;
import androidx.constraintlayout.core.motion.key.MotionKeyCycle;
import androidx.constraintlayout.core.motion.key.MotionKeyPosition;
import androidx.constraintlayout.core.motion.utils.Easing;
import androidx.constraintlayout.core.motion.utils.KeyCache;
import androidx.constraintlayout.core.motion.utils.SpringStopEngine;
import androidx.constraintlayout.core.motion.utils.StopEngine;
import androidx.constraintlayout.core.motion.utils.StopLogicEngine;
import androidx.constraintlayout.core.motion.utils.TypedBundle;
import androidx.constraintlayout.core.motion.utils.TypedValues;
import androidx.constraintlayout.core.motion.utils.Utils;
import androidx.constraintlayout.core.widgets.ConstraintWidget;
import androidx.constraintlayout.core.widgets.ConstraintWidgetContainer;

import java.util.ArrayList;
import java.util.Collection;
import java.util.HashMap;

public class Transition implements TypedValues {
    private static final boolean DEBUG = false;
    public static final int START = 0;
    public static final int END = 1;
    public static final int INTERPOLATED = 2;
    static final int EASE_IN_OUT = 0;
    static final int EASE_IN = 1;
    static final int EASE_OUT = 2;
    static final int LINEAR = 3;
    static final int BOUNCE = 4;
    static final int OVERSHOOT = 5;
    static final int ANTICIPATE = 6;
    private static final int SPLINE_STRING = -1;
    @SuppressWarnings("unused")
    private static final int INTERPOLATOR_REFERENCE_ID = -2;
    private HashMap<Integer, HashMap<String, KeyPosition>> mKeyPositions = new HashMap<>();
    private HashMap<String, WidgetState> mState = new HashMap<>();
    private TypedBundle mBundle = new TypedBundle();
    // Interpolation
    private int mDefaultInterpolator = 0;
    private String mDefaultInterpolatorString = null;
    private Easing mEasing = null;
    private int mAutoTransition = 0;
    private int mDuration = 400;
    private float mStagger = 0.0f;
    private OnSwipe mOnSwipe = null;
    final CorePixelDp mToPixel; // Todo placed here as a temp till the refactor is done
    int mParentStartWidth, mParentStartHeight;
    int mParentEndWidth, mParentEndHeight;
    int mParentInterpolatedWidth, mParentInterpolateHeight;
    boolean mWrap;

    public Transition(@NonNull CorePixelDp dpToPixel) {
        mToPixel = dpToPixel;
    }

    // @TODO: add description
    @SuppressWarnings("HiddenTypeParameter")
    OnSwipe createOnSwipe() {
        return mOnSwipe = new OnSwipe();
    }

    // @TODO: add description
    public boolean hasOnSwipe() {
        return mOnSwipe != null;
    }

    static class OnSwipe {
        String mAnchorId;
        private int mAnchorSide;
        private StopEngine mEngine;
        public static final int ANCHOR_SIDE_TOP = 0;
        public static final int ANCHOR_SIDE_LEFT = 1;
        public static final int ANCHOR_SIDE_RIGHT = 2;
        public static final int ANCHOR_SIDE_BOTTOM = 3;
        public static final int ANCHOR_SIDE_MIDDLE = 4;
        public static final int ANCHOR_SIDE_START = 5;
        public static final int ANCHOR_SIDE_END = 6;
        public static final String[] SIDES = {"top", "left", "right",
                "bottom", "middle", "start", "end"};
        private static final float[][] TOUCH_SIDES = {
                {0.5f, 0.0f}, // top
                {0.0f, 0.5f}, // left
                {1.0f, 0.5f}, // right
                {0.5f, 1.0f}, // bottom
                {0.5f, 0.5f}, // middle
                {0.0f, 0.5f}, // start TODO (dynamically updated)
                {1.0f, 0.5f}, // end  TODO (dynamically updated)
        };

        @SuppressWarnings("unused")
        private String mRotationCenterId;
        String mLimitBoundsTo;
        @SuppressWarnings("unused")
        private boolean mDragVertical = true;
        private int mDragDirection = 0;
        public static final int DRAG_UP = 0;
        public static final int DRAG_DOWN = 1;
        public static final int DRAG_LEFT = 2;
        public static final int DRAG_RIGHT = 3;
        public static final int DRAG_START = 4;
        public static final int DRAG_END = 5;
        public static final int DRAG_CLOCKWISE = 6;
        public static final int DRAG_ANTICLOCKWISE = 7;
        public static final String[] DIRECTIONS = {"up", "down", "left", "right", "start",
                "end", "clockwise", "anticlockwise"};

        private float mDragScale = 1;
        @SuppressWarnings("unused")
        private float mDragThreshold = 10;
        private int mAutoCompleteMode = 0;
        public static final int MODE_CONTINUOUS_VELOCITY = 0;
        public static final int MODE_SPRING = 1;
        public static final String[] MODE = {"velocity", "spring"};
        private float mMaxVelocity = 4.f;
        private float mMaxAcceleration = 1.2f;

        // On touch up what happens
        private int mOnTouchUp = 0;
        public static final int ON_UP_AUTOCOMPLETE = 0;
        public static final int ON_UP_AUTOCOMPLETE_TO_START = 1;
        public static final int ON_UP_AUTOCOMPLETE_TO_END = 2;
        public static final int ON_UP_STOP = 3;
        public static final int ON_UP_DECELERATE = 4;
        public static final int ON_UP_DECELERATE_AND_COMPLETE = 5;
        public static final int ON_UP_NEVER_COMPLETE_TO_START = 6;
        public static final int ON_UP_NEVER_COMPLETE_TO_END = 7;
        public static final String[] TOUCH_UP = {"autocomplete", "toStart",
                "toEnd", "stop", "decelerate", "decelerateComplete",
                "neverCompleteStart", "neverCompleteEnd"};

        private float mSpringMass = 1;
        private float mSpringStiffness = 400;
        private float mSpringDamping = 10;
        private float mSpringStopThreshold = 0.01f;
        private float mDestination = 0.0f;

        // In spring mode what happens at the boundary
        private int mSpringBoundary = 0;
        public static final int BOUNDARY_OVERSHOOT = 0;
        public static final int BOUNDARY_BOUNCE_START = 1;
        public static final int BOUNDARY_BOUNCE_END = 2;
        public static final int BOUNDARY_BOUNCE_BOTH = 3;
        public static final String[] BOUNDARY = {"overshoot", "bounceStart",
                "bounceEnd", "bounceBoth"};

        private static final float[][] TOUCH_DIRECTION = {
                {0.0f, -1.0f}, // up
                {0.0f, 1.0f}, // down
                {-1.0f, 0.0f}, // left
                {1.0f, 0.0f}, // right
                {-1.0f, 0.0f}, // start (dynamically updated)
                {1.0f, 0.0f}, // end  (dynamically updated)
        };
        private long mStart;

        float getScale() {
            return mDragScale;
        }

        float[] getDirection() {
            return TOUCH_DIRECTION[mDragDirection];
        }

        float[] getSide() {
            return TOUCH_SIDES[mAnchorSide];
        }

        void setAnchorId(String anchorId) {
            this.mAnchorId = anchorId;
        }

        void setAnchorSide(int anchorSide) {
            this.mAnchorSide = anchorSide;
        }

        void setRotationCenterId(String rotationCenterId) {
            this.mRotationCenterId = rotationCenterId;
        }

        void setLimitBoundsTo(String limitBoundsTo) {
            this.mLimitBoundsTo = limitBoundsTo;
        }

        void setDragDirection(int dragDirection) {
            this.mDragDirection = dragDirection;
            mDragVertical = (mDragDirection < 2);
        }

        void setDragScale(float dragScale) {
            if (Float.isNaN(dragScale)) {
                return;
            }
            this.mDragScale = dragScale;
        }

        void setDragThreshold(float dragThreshold) {
            if (Float.isNaN(dragThreshold)) {
                return;
            }
            this.mDragThreshold = dragThreshold;
        }

        void setAutoCompleteMode(int mAutoCompleteMode) {
            this.mAutoCompleteMode = mAutoCompleteMode;
        }

        void setMaxVelocity(float maxVelocity) {
            if (Float.isNaN(maxVelocity)) {
                return;
            }
            this.mMaxVelocity = maxVelocity;
        }

        void setMaxAcceleration(float maxAcceleration) {
            if (Float.isNaN(maxAcceleration)) {
                return;
            }
            this.mMaxAcceleration = maxAcceleration;
        }

        void setOnTouchUp(int onTouchUp) {
            this.mOnTouchUp = onTouchUp;
        }

        void setSpringMass(float mSpringMass) {
            if (Float.isNaN(mSpringMass)) {
                return;
            }
            this.mSpringMass = mSpringMass;
        }

        void setSpringStiffness(float mSpringStiffness) {
            if (Float.isNaN(mSpringStiffness)) {
                return;
            }
            this.mSpringStiffness = mSpringStiffness;
        }

        void setSpringDamping(float mSpringDamping) {
            if (Float.isNaN(mSpringDamping)) {
                return;
            }
            this.mSpringDamping = mSpringDamping;
        }

        void setSpringStopThreshold(float mSpringStopThreshold) {
            if (Float.isNaN(mSpringStopThreshold)) {
                return;
            }
            this.mSpringStopThreshold = mSpringStopThreshold;
        }

        void setSpringBoundary(int mSpringBoundary) {
            this.mSpringBoundary = mSpringBoundary;
        }

        float getDestinationPosition(float currentPosition, float velocity, float duration) {
            float rest = currentPosition + 0.5f * Math.abs(velocity) * velocity / mMaxAcceleration;
            switch (mOnTouchUp) {
                case ON_UP_AUTOCOMPLETE_TO_START:
                    if (currentPosition >= 1f) {
                        return 1;
                    }
                    return 0;
                case ON_UP_NEVER_COMPLETE_TO_END:
                    return 0;
                case ON_UP_AUTOCOMPLETE_TO_END:
                    if (currentPosition <= 0f) {
                        return 0;
                    }
                    return 1;
                case ON_UP_NEVER_COMPLETE_TO_START:
                    return 1;
                case ON_UP_STOP:
                    return Float.NaN;
                case ON_UP_DECELERATE:
                    return Math.max(0, Math.min(1, rest));
                case ON_UP_DECELERATE_AND_COMPLETE: // complete if within 20% of edge #todo improve
                    if (rest > 0.2f && rest < 0.8f) {
                        return rest;
                    } else {
                        return rest > .5f ? 1 : 0;
                    }
                case ON_UP_AUTOCOMPLETE:
            }

            if (DEBUG) {
                Utils.log(" currentPosition = " + currentPosition);
                Utils.log("        velocity = " + velocity);
                Utils.log("            peek = " + rest);
                Utils.log("mMaxAcceleration = " + mMaxAcceleration);
            }
            return rest > .5 ? 1 : 0;
        }

        void config(float position, float velocity, long start, float duration) {
            mStart = start;
            if (Math.abs(velocity) > mMaxVelocity) {
                velocity = mMaxVelocity * Math.signum(velocity);
            }
            mDestination = getDestinationPosition(position, velocity, duration);
            if (mDestination == position) {
                mEngine = null;
                return;
            }
            if ((mOnTouchUp == ON_UP_DECELERATE)
                    && (mAutoCompleteMode == MODE_CONTINUOUS_VELOCITY)) {
                StopLogicEngine.Decelerate sld;
                if (mEngine instanceof StopLogicEngine.Decelerate) {
                    sld = (StopLogicEngine.Decelerate) mEngine;
                } else {
                    mEngine = sld = new StopLogicEngine.Decelerate();
                }
                sld.config(position, mDestination, velocity);
                return;
            }


            if (mAutoCompleteMode == MODE_CONTINUOUS_VELOCITY) {
                StopLogicEngine sl;
                if (mEngine instanceof StopLogicEngine) {
                    sl = (StopLogicEngine) mEngine;
                } else {
                    mEngine = sl = new StopLogicEngine();
                }

                sl.config(position, mDestination, velocity,
                        duration, mMaxAcceleration,
                        mMaxVelocity);
                return;
            }
            SpringStopEngine sl;
            if (mEngine instanceof SpringStopEngine) {
                sl = (SpringStopEngine) mEngine;
            } else {
                mEngine = sl = new SpringStopEngine();
            }

            sl.springConfig(position, mDestination, velocity,
                    mSpringMass,
                    mSpringStiffness,
                    mSpringDamping,
                    mSpringStopThreshold, mSpringBoundary);
        }

        /**
         * @param currentTime time in nanoseconds
         * @return new values of progress
         */
        public float getTouchUpProgress(long currentTime) {
            float time = (currentTime - mStart) * 1E-9f;
            float pos = mEngine.getInterpolation(time);
            if (mEngine.isStopped()) {
                pos = mDestination;
            }
            return pos;
        }

        public void printInfo() {
            if (mAutoCompleteMode == MODE_CONTINUOUS_VELOCITY) {
                System.out.println("velocity = " + mEngine.getVelocity());
                System.out.println("mMaxAcceleration = " + mMaxAcceleration);
                System.out.println("mMaxVelocity = " + mMaxVelocity);
            } else {
                System.out.println("mSpringMass          = " + mSpringMass);
                System.out.println("mSpringStiffness     = " + mSpringStiffness);
                System.out.println("mSpringDamping       = " + mSpringDamping);
                System.out.println("mSpringStopThreshold = " + mSpringStopThreshold);
                System.out.println("mSpringBoundary      = " + mSpringBoundary);
            }
        }

        public boolean isNotDone(float progress) {
            if (mOnTouchUp == ON_UP_STOP) {
                return false;
            }
            return mEngine != null && !mEngine.isStopped();
        }
    }

    /**
     * For the given position (in the MotionLayout coordinate space) determine whether we accept
     * the first down for on swipe.
     * <p>
     * This is based off {@link OnSwipe#mLimitBoundsTo}. If null, we accept the drag at any
     * position, otherwise, we only accept it if it's within its bounds.
     */
    @RestrictTo(RestrictTo.Scope.LIBRARY_GROUP)
    public boolean isFirstDownAccepted(float posX, float posY) {
        if (mOnSwipe == null) {
            return false;
        }

        if (mOnSwipe.mLimitBoundsTo != null) {
            WidgetState targetWidget = mState.get(mOnSwipe.mLimitBoundsTo);
            if (targetWidget == null) {
                System.err.println("mLimitBoundsTo target is null");
                return false;
            }
            // Calculate against the interpolated/current frame
            WidgetFrame frame = targetWidget.getFrame(2);
            return posX >= frame.left && posX < frame.right && posY >= frame.top
                    && posY < frame.bottom;
        } else {
            return true;
        }
    }

    /**
     * Converts from xy drag to progress
     * This should be used till touch up
     *
     * @param baseW parent width
     * @param baseH parent height
     * @param dx    change in x
     * @param dy    change in y
     * @return the change in progress
     */
    public float dragToProgress(float currentProgress, int baseW, int baseH, float dx, float dy) {
        Collection<WidgetState> widgets = mState.values();
        WidgetState childWidget = null;
        for (WidgetState widget : widgets) {
            childWidget = widget;
            break;
        }
        if (mOnSwipe == null || childWidget == null) {
            if (childWidget != null) {
                return -dy / childWidget.mParentHeight;
            }
            return 1.0f;
        }
        if (mOnSwipe.mAnchorId == null) {

            float[] dir = mOnSwipe.getDirection();
            float motionDpDtX = childWidget.mParentHeight;
            float motionDpDtY = childWidget.mParentHeight;

            float drag = (dir[0] != 0) ? dx * Math.abs(dir[0]) / motionDpDtX
                    : dy * Math.abs(dir[1]) / motionDpDtY;
            return drag * mOnSwipe.getScale();
        }
        WidgetState base = mState.get(mOnSwipe.mAnchorId);
        float[] dir = mOnSwipe.getDirection();
        float[] side = mOnSwipe.getSide();
        float[] motionDpDt = new float[2];

        base.interpolate(baseW, baseH, currentProgress, this);
        base.mMotionControl.getDpDt(currentProgress, side[0], side[1], motionDpDt);
        float drag = (dir[0] != 0) ? dx * Math.abs(dir[0]) / motionDpDt[0]
                : dy * Math.abs(dir[1]) / motionDpDt[1];
        if (DEBUG) {
            Utils.log(" drag " + drag);
        }
        return drag * mOnSwipe.getScale();
    }

    /**
     * Set the start of the touch up
     *
     * @param currentProgress 0...1 progress in
     * @param currentTime     time in nanoseconds
     * @param velocityX       pixels per millisecond
     * @param velocityY       pixels per millisecond
     */
    public void setTouchUp(float currentProgress,
            long currentTime,
            float velocityX,
            float velocityY) {
        if (mOnSwipe != null) {
            if (DEBUG) {
                Utils.log(" >>> velocity x,y = " + velocityX + " , " + velocityY);
            }
            WidgetState base = mState.get(mOnSwipe.mAnchorId);
            float[] motionDpDt = new float[2];
            float[] dir = mOnSwipe.getDirection();
            float[] side = mOnSwipe.getSide();
            base.mMotionControl.getDpDt(currentProgress, side[0], side[1], motionDpDt);
            float movementInDir = dir[0] * motionDpDt[0] + dir[1] * motionDpDt[1];
            if (Math.abs(movementInDir) < 0.01) {
                if (DEBUG) {
                    Utils.log(" >>> cap minimum v!! ");
                }
                motionDpDt[0] = .01f;
                motionDpDt[1] = .01f;
            }

            float drag = (dir[0] != 0) ? velocityX / motionDpDt[0] : velocityY / motionDpDt[1];
            drag *= mOnSwipe.getScale();
            if (DEBUG) {
                Utils.log(" >>> velocity        " + drag);
                Utils.log(" >>> mDuration       " + mDuration);
                Utils.log(" >>> currentProgress " + currentProgress);
            }
            mOnSwipe.config(currentProgress, drag, currentTime, mDuration * 1E-3f);
            if (DEBUG) {
                mOnSwipe.printInfo();
            }
        }
    }

    /**
     * get the current touch up progress current time in nanoseconds
     * (ideally coming from an animation clock)
     *
     * @param currentTime in nanoseconds
     * @return progress
     */
    public float getTouchUpProgress(long currentTime) {
        if (mOnSwipe != null) {
            return mOnSwipe.getTouchUpProgress(currentTime);
        }
        return 0;
    }

    /**
     * Are we still animating
     *
     * @param currentProgress motion progress
     * @return true to continue moving
     */
    public boolean isTouchNotDone(float currentProgress) {
        return mOnSwipe.isNotDone(currentProgress);
    }

    /**
     * get the interpolater based on a constant or a string
     */
    public static Interpolator getInterpolator(int interpolator, String interpolatorString) {
        switch (interpolator) {
            case SPLINE_STRING:
                return v -> (float) Easing.getInterpolator(interpolatorString).get(v);
            case EASE_IN_OUT:
                return v -> (float) Easing.getInterpolator("standard").get(v);
            case EASE_IN:
                return v -> (float) Easing.getInterpolator("accelerate").get(v);
            case EASE_OUT:
                return v -> (float) Easing.getInterpolator("decelerate").get(v);
            case LINEAR:
                return v -> (float) Easing.getInterpolator("linear").get(v);
            case ANTICIPATE:
                return v -> (float) Easing.getInterpolator("anticipate").get(v);
            case OVERSHOOT:
                return v -> (float) Easing.getInterpolator("overshoot").get(v);
            case BOUNCE: // TODO make a better bounce
                return v -> (float) Easing.getInterpolator("spline(0.0, 0.2, 0.4, 0.6, "
                        + "0.8 ,1.0, 0.8, 1.0, 0.9, 1.0)").get(v);
        }
        return null;
    }

    // @TODO: add description
    @SuppressWarnings("HiddenTypeParameter")
    public KeyPosition findPreviousPosition(String target, int frameNumber) {
        while (frameNumber >= 0) {
            HashMap<String, KeyPosition> map = mKeyPositions.get(frameNumber);
            if (map != null) {
                KeyPosition keyPosition = map.get(target);
                if (keyPosition != null) {
                    return keyPosition;
                }
            }
            frameNumber--;
        }
        return null;
    }

    // @TODO: add description
    @SuppressWarnings("HiddenTypeParameter")
    public KeyPosition findNextPosition(String target, int frameNumber) {
        while (frameNumber <= 100) {
            HashMap<String, KeyPosition> map = mKeyPositions.get(frameNumber);
            if (map != null) {
                KeyPosition keyPosition = map.get(target);
                if (keyPosition != null) {
                    return keyPosition;
                }
            }
            frameNumber++;
        }
        return null;
    }

    // @TODO: add description
    public int getNumberKeyPositions(WidgetFrame frame) {
        int numKeyPositions = 0;
        int frameNumber = 0;
        while (frameNumber <= 100) {
            HashMap<String, KeyPosition> map = mKeyPositions.get(frameNumber);
            if (map != null) {
                KeyPosition keyPosition = map.get(frame.widget.stringId);
                if (keyPosition != null) {
                    numKeyPositions++;
                }
            }
            frameNumber++;
        }
        return numKeyPositions;
    }

    // @TODO: add description
    public Motion getMotion(String id) {
        return getWidgetState(id, null, 0).mMotionControl;
    }

    // @TODO: add description
    public void fillKeyPositions(WidgetFrame frame, float[] x, float[] y, float[] pos) {
        int numKeyPositions = 0;
        int frameNumber = 0;
        while (frameNumber <= 100) {
            HashMap<String, KeyPosition> map = mKeyPositions.get(frameNumber);
            if (map != null) {
                KeyPosition keyPosition = map.get(frame.widget.stringId);
                if (keyPosition != null) {
                    x[numKeyPositions] = keyPosition.mX;
                    y[numKeyPositions] = keyPosition.mY;
                    pos[numKeyPositions] = keyPosition.mFrame;
                    numKeyPositions++;
                }
            }
            frameNumber++;
        }
    }

    // @TODO: add description
    public boolean hasPositionKeyframes() {
        return mKeyPositions.size() > 0;
    }

    // @TODO: add description
    public void setTransitionProperties(TypedBundle bundle) {
        bundle.applyDelta(mBundle);
        bundle.applyDelta(this);
    }

    @Override
    public boolean setValue(int id, int value) {
        return false;
    }

    @Override
    public boolean setValue(int id, float value) {
        if (id == TypedValues.TransitionType.TYPE_STAGGERED) {
            mStagger = value;
        }
        return false;
    }

    @Override
    public boolean setValue(int id, String value) {
        if (id == TransitionType.TYPE_INTERPOLATOR) {
            mEasing = Easing.getInterpolator(mDefaultInterpolatorString = value);
        }
        return false;
    }

    @Override
    public boolean setValue(int id, boolean value) {
        return false;
    }

    @Override
    public int getId(String name) {
        return 0;
    }

    public boolean isEmpty() {
        return mState.isEmpty();
    }

    // @TODO: add description
    public void clear() {
        mState.clear();
    }

    /**
     * Reset animation properties of the Transition.
     * <p>
     * This will not affect the internal model of the widgets (a.k.a. {@link #mState}).
     */
    void resetProperties() {
        mOnSwipe = null;
        mBundle.clear();
    }

    // @TODO: add description
    public boolean contains(String key) {
        return mState.containsKey(key);
    }

    // @TODO: add description
    public void addKeyPosition(String target, TypedBundle bundle) {
        getWidgetState(target, null, 0).setKeyPosition(bundle);
    }

    // @TODO: add description
    public void addKeyAttribute(String target, TypedBundle bundle) {
        getWidgetState(target, null, 0).setKeyAttribute(bundle);
    }

    /**
     * Add a key attribute and the custom variables into the
     * @param target the id of the target
     * @param bundle the key attributes bundle containing position etc.
     * @param custom the customVariables to add at that position
     */
    public void addKeyAttribute(String target, TypedBundle bundle, CustomVariable[]custom) {
        getWidgetState(target, null, 0).setKeyAttribute(bundle,custom);
    }

    // @TODO: add description
    public void addKeyCycle(String target, TypedBundle bundle) {
        getWidgetState(target, null, 0).setKeyCycle(bundle);
    }

    // @TODO: add description
    public void addKeyPosition(String target, int frame, int type, float x, float y) {
        TypedBundle bundle = new TypedBundle();
        bundle.add(TypedValues.PositionType.TYPE_POSITION_TYPE, 2);
        bundle.add(TypedValues.TYPE_FRAME_POSITION, frame);
        bundle.add(TypedValues.PositionType.TYPE_PERCENT_X, x);
        bundle.add(TypedValues.PositionType.TYPE_PERCENT_Y, y);
        getWidgetState(target, null, 0).setKeyPosition(bundle);

        KeyPosition keyPosition = new KeyPosition(target, frame, type, x, y);
        HashMap<String, KeyPosition> map = mKeyPositions.get(frame);
        if (map == null) {
            map = new HashMap<>();
            mKeyPositions.put(frame, map);
        }
        map.put(target, keyPosition);
    }

    // @TODO: add description
    public void addCustomFloat(int state, String widgetId, String property, float value) {
        WidgetState widgetState = getWidgetState(widgetId, null, state);
        WidgetFrame frame = widgetState.getFrame(state);
        frame.addCustomFloat(property, value);
    }

    // @TODO: add description
    public void addCustomColor(int state, String widgetId, String property, int color) {
        WidgetState widgetState = getWidgetState(widgetId, null, state);
        WidgetFrame frame = widgetState.getFrame(state);
        frame.addCustomColor(property, color);
    }

    private void calculateParentDimensions(float progress) {
        mParentInterpolatedWidth = (int) (0.5f +
                mParentStartWidth + (mParentEndWidth - mParentStartWidth) * progress);
        mParentInterpolateHeight = (int) (0.5f +
                mParentStartHeight + (mParentEndHeight - mParentStartHeight) * progress);
    }

    public int getInterpolatedWidth() {
        return mParentInterpolatedWidth;
    }

    public int getInterpolatedHeight() {
        return mParentInterpolateHeight;
    }
    /**
     * Update container of parameters for the state
     *
     * @param container contains all the widget parameters
     * @param state     starting or ending
     */
    public void updateFrom(ConstraintWidgetContainer container, int state) {
        mWrap = container.mListDimensionBehaviors[0]
                == ConstraintWidget.DimensionBehaviour.WRAP_CONTENT;
        mWrap |= container.mListDimensionBehaviors[1]
                == ConstraintWidget.DimensionBehaviour.WRAP_CONTENT;
        if (state == START) {
            mParentInterpolatedWidth = mParentStartWidth = container.getWidth();
            mParentInterpolateHeight = mParentStartHeight = container.getHeight();
        } else {
            mParentEndWidth = container.getWidth();
            mParentEndHeight = container.getHeight();
        }
        final ArrayList<ConstraintWidget> children = container.getChildren();
        final int count = children.size();
        WidgetState[] states = new WidgetState[count];

        for (int i = 0; i < count; i++) {
            ConstraintWidget child = children.get(i);
            WidgetState widgetState = getWidgetState(child.stringId, null, state);
            states[i] = widgetState;
            widgetState.update(child, state);
            String id = widgetState.getPathRelativeId();
            if (id != null) {
                widgetState.setPathRelative(getWidgetState(id, null, state));
            }
        }

        calcStagger();
    }

    // @TODO: add description
    public void interpolate(int parentWidth, int parentHeight, float progress) {
        if (mWrap) {
            calculateParentDimensions(progress);
        }

        if (mEasing != null) {
            progress = (float) mEasing.get(progress);
        }
        for (String key : mState.keySet()) {
            WidgetState widget = mState.get(key);
            widget.interpolate(parentWidth, parentHeight, progress, this);
        }
    }

    // @TODO: add description
    public WidgetFrame getStart(String id) {
        WidgetState widgetState = mState.get(id);
        if (widgetState == null) {
            return null;
        }
        return widgetState.mStart;
    }

    // @TODO: add description
    public WidgetFrame getEnd(String id) {
        WidgetState widgetState = mState.get(id);
        if (widgetState == null) {
            return null;
        }
        return widgetState.mEnd;
    }

    // @TODO: add description
    public WidgetFrame getInterpolated(String id) {
        WidgetState widgetState = mState.get(id);
        if (widgetState == null) {
            return null;
        }
        return widgetState.mInterpolated;
    }

    // @TODO: add description
    public float[] getPath(String id) {
        WidgetState widgetState = mState.get(id);
        int duration = 1000;
        int frames = duration / 16;
        float[] mPoints = new float[frames * 2];
        widgetState.mMotionControl.buildPath(mPoints, frames);
        return mPoints;
    }

    // @TODO: add description
    public int getKeyFrames(String id, float[] rectangles, int[] pathMode, int[] position) {
        WidgetState widgetState = mState.get(id);
        return widgetState.mMotionControl.buildKeyFrames(rectangles, pathMode, position);
    }

    @SuppressWarnings("unused")
    private WidgetState getWidgetState(String widgetId) {
        return this.mState.get(widgetId);
    }

    public WidgetState getWidgetState(String widgetId,
            ConstraintWidget child,
            int transitionState) {
        WidgetState widgetState = this.mState.get(widgetId);
        if (widgetState == null) {
            widgetState = new WidgetState();
            mBundle.applyDelta(widgetState.mMotionControl);
            widgetState.mMotionWidgetStart.updateMotion(widgetState.mMotionControl);
            mState.put(widgetId, widgetState);
            if (child != null) {
                widgetState.update(child, transitionState);
            }
        }
        return widgetState;
    }

    /**
     * Used in debug draw
     */
    public WidgetFrame getStart(ConstraintWidget child) {
        return getWidgetState(child.stringId, null, Transition.START).mStart;
    }

    /**
     * Used in debug draw
     */
    public WidgetFrame getEnd(ConstraintWidget child) {
        return getWidgetState(child.stringId, null, Transition.END).mEnd;
    }

    /**
     * Used after the interpolation
     */
    public WidgetFrame getInterpolated(ConstraintWidget child) {
        return getWidgetState(child.stringId, null, Transition.INTERPOLATED).mInterpolated;
    }

    /**
     * This gets the interpolator being used
     */
    public Interpolator getInterpolator() {
        return getInterpolator(mDefaultInterpolator, mDefaultInterpolatorString);
    }

    /**
     * This gets the auto transition mode being used
     */
    public int getAutoTransition() {
        return mAutoTransition;
    }

    public static class WidgetState {
        WidgetFrame mStart;
        WidgetFrame mEnd;
        WidgetFrame mInterpolated;
        Motion mMotionControl;
        boolean mNeedSetup = true;
        MotionWidget mMotionWidgetStart;
        MotionWidget mMotionWidgetEnd;
        MotionWidget mMotionWidgetInterpolated;
        KeyCache mKeyCache = new KeyCache();
        int mParentHeight = -1;
        int mParentWidth = -1;

        public WidgetState() {
            mStart = new WidgetFrame();
            mEnd = new WidgetFrame();
            mInterpolated = new WidgetFrame();
            mMotionWidgetStart = new MotionWidget(mStart);
            mMotionWidgetEnd = new MotionWidget(mEnd);
            mMotionWidgetInterpolated = new MotionWidget(mInterpolated);
            mMotionControl = new Motion(mMotionWidgetStart);
            mMotionControl.setStart(mMotionWidgetStart);
            mMotionControl.setEnd(mMotionWidgetEnd);
        }

        public void setKeyPosition(TypedBundle prop) {
            MotionKeyPosition keyPosition = new MotionKeyPosition();
            prop.applyDelta(keyPosition);
            mMotionControl.addKey(keyPosition);
        }

        public void setKeyAttribute(TypedBundle prop) {
            MotionKeyAttributes keyAttributes = new MotionKeyAttributes();
            prop.applyDelta(keyAttributes);
            mMotionControl.addKey(keyAttributes);
        }

        /**
         * Set tge keyAttribute bundle and associated custom attributes
         * @param prop
         * @param custom
         */
        public void setKeyAttribute(TypedBundle prop, CustomVariable[] custom) {
            MotionKeyAttributes keyAttributes = new MotionKeyAttributes();
            prop.applyDelta(keyAttributes);
            if (custom != null) {
                for (int i = 0; i < custom.length; i++) {
                    keyAttributes.mCustom.put( custom[i].getName(), custom[i]);
                }
            }
            mMotionControl.addKey(keyAttributes);
        }

        public void setKeyCycle(TypedBundle prop) {
            MotionKeyCycle keyAttributes = new MotionKeyCycle();
            prop.applyDelta(keyAttributes);
            mMotionControl.addKey(keyAttributes);
        }

        public void update(ConstraintWidget child, int state) {
            if (state == START) {
                mStart.update(child);
                mMotionWidgetStart.updateMotion(mMotionWidgetStart);
                mMotionControl.setStart(mMotionWidgetStart);
                mNeedSetup = true;
            } else if (state == END) {
                mEnd.update(child);
                mMotionControl.setEnd(mMotionWidgetEnd);
                mNeedSetup = true;
            }
            mParentWidth = -1;
        }

        /**
         * Return the id of the widget to animate relative to
         *
         * @return id of widget or null
         */
        String getPathRelativeId() {
            return mMotionControl.getAnimateRelativeTo();
        }

        public WidgetFrame getFrame(int type) {
            if (type == START) {
                return mStart;
            } else if (type == END) {
                return mEnd;
            }
            return mInterpolated;
        }

        public void interpolate(int parentWidth,
                int parentHeight,
                float progress,
                Transition transition) {
            // TODO  only update if parentHeight != mParentHeight || parentWidth != mParentWidth) {
            mParentHeight = parentHeight;
            mParentWidth = parentWidth;
            if (mNeedSetup) {
                mMotionControl.setup(parentWidth, parentHeight, 1, System.nanoTime());
                mNeedSetup = false;
            }
            WidgetFrame.interpolate(parentWidth, parentHeight,
                    mInterpolated, mStart, mEnd, transition, progress);
            mInterpolated.interpolatedPos = progress;
            mMotionControl.interpolate(mMotionWidgetInterpolated,
                    progress, System.nanoTime(), mKeyCache);
        }

        public void setPathRelative(WidgetState widgetState) {
            mMotionControl.setupRelative(widgetState.mMotionControl);
        }
    }

    static class KeyPosition {
        int mFrame;
        String mTarget;
        int mType;
        float mX;
        float mY;

        KeyPosition(String target, int frame, int type, float x, float y) {
            this.mTarget = target;
            this.mFrame = frame;
            this.mType = type;
            this.mX = x;
            this.mY = y;
        }
    }

    public void calcStagger() {
        if (mStagger == 0.0f) {
            return;
        }
        boolean flip = mStagger < 0.0;

        float stagger = Math.abs(mStagger);
        float min = Float.MAX_VALUE, max = -Float.MAX_VALUE;
        boolean useMotionStagger = false;

        for (String widgetId : mState.keySet()) {
            WidgetState widgetState = mState.get(widgetId);
            Motion f = widgetState.mMotionControl;
            if (!Float.isNaN(f.getMotionStagger())) {
                useMotionStagger = true;
                break;
            }
        }
        if (useMotionStagger) {
            for (String widgetId : mState.keySet()) {
                WidgetState widgetState = mState.get(widgetId);
                Motion f = widgetState.mMotionControl;
                float widgetStagger = f.getMotionStagger();
                if (!Float.isNaN(widgetStagger)) {
                    min = Math.min(min, widgetStagger);
                    max = Math.max(max, widgetStagger);
                }
            }

            for (String widgetId : mState.keySet()) {
                WidgetState widgetState = mState.get(widgetId);
                Motion f = widgetState.mMotionControl;

                float widgetStagger = f.getMotionStagger();
                if (!Float.isNaN(widgetStagger)) {
                    float scale = 1 / (1 - stagger);

                    float offset = stagger - stagger * (widgetStagger - min) / (max - min);
                    if (flip) {
                        offset = stagger - stagger
                                * ((max - widgetStagger) / (max - min));
                    }
                    f.setStaggerScale(scale);
                    f.setStaggerOffset(offset);
                }
            }

        } else {
            for (String widgetId : mState.keySet()) {
                WidgetState widgetState = mState.get(widgetId);
                Motion f = widgetState.mMotionControl;
                float x = f.getFinalX();
                float y = f.getFinalY();
                float widgetStagger = x + y;
                min = Math.min(min, widgetStagger);
                max = Math.max(max, widgetStagger);
            }

            for (String widgetId : mState.keySet()) {
                WidgetState widgetState = mState.get(widgetId);
                Motion f = widgetState.mMotionControl;
                float x = f.getFinalX();
                float y = f.getFinalY();
                float widgetStagger = x + y;
                float offset = stagger - stagger * (widgetStagger - min) / (max - min);
                if (flip) {
                    offset = stagger - stagger
                            * ((max - widgetStagger) / (max - min));
                }

                float scale = 1 / (1 - stagger);
                f.setStaggerScale(scale);
                f.setStaggerOffset(offset);
            }
        }
    }
}