/*
 * Copyright (C) 2010 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 android.animation;

import android.annotation.AnimatorRes;
import android.annotation.AnyRes;
import android.annotation.NonNull;
import android.content.Context;
import android.content.pm.ActivityInfo.Config;
import android.content.res.ConfigurationBoundResourceCache;
import android.content.res.ConstantState;
import android.content.res.Resources;
import android.content.res.Resources.NotFoundException;
import android.content.res.Resources.Theme;
import android.content.res.TypedArray;
import android.content.res.XmlResourceParser;
import android.graphics.Path;
import android.util.AttributeSet;
import android.util.Log;
import android.util.PathParser;
import android.util.StateSet;
import android.util.TypedValue;
import android.util.Xml;
import android.view.InflateException;
import android.view.animation.AnimationUtils;
import android.view.animation.BaseInterpolator;
import android.view.animation.Interpolator;

import com.android.internal.R;

import org.xmlpull.v1.XmlPullParser;
import org.xmlpull.v1.XmlPullParserException;

import java.io.IOException;
import java.util.ArrayList;

This class is used to instantiate animator XML files into Animator objects.

For performance reasons, inflation relies heavily on pre-processing of
XML files that is done at build time. Therefore, it is not currently possible
to use this inflater with an XmlPullParser over a plain XML file at runtime;
it only works with an XmlPullParser returned from a compiled resource (R.
something file.)
/**
 * This class is used to instantiate animator XML files into Animator objects.
 * <p>
 * For performance reasons, inflation relies heavily on pre-processing of
 * XML files that is done at build time. Therefore, it is not currently possible
 * to use this inflater with an XmlPullParser over a plain XML file at runtime;
 * it only works with an XmlPullParser returned from a compiled resource (R.
 * <em>something</em> file.)
 */
public class AnimatorInflater {
    private static final String TAG = "AnimatorInflater";
    
These flags are used when parsing AnimatorSet objects
/**
     * These flags are used when parsing AnimatorSet objects
     */
    private static final int TOGETHER = 0;
    private static final int SEQUENTIALLY = 1;

    
Enum values used in XML attributes to indicate the value for mValueType
/**
     * Enum values used in XML attributes to indicate the value for mValueType
     */
    private static final int VALUE_TYPE_FLOAT       = 0;
    private static final int VALUE_TYPE_INT         = 1;
    private static final int VALUE_TYPE_PATH        = 2;
    private static final int VALUE_TYPE_COLOR       = 3;
    private static final int VALUE_TYPE_UNDEFINED   = 4;

    private static final boolean DBG_ANIMATOR_INFLATER = false;

    // used to calculate changing configs for resource references
    private static final TypedValue sTmpTypedValue = new TypedValue();

    
Loads an Animator object from a resource 
Params:
context – Application context used to access resources
id – The resource id of the animation to load
Throws:
NotFoundException – when the animation cannot be loaded
Returns:
The animator object reference by the specified id/**
     * Loads an {@link Animator} object from a resource
     *
     * @param context Application context used to access resources
     * @param id The resource id of the animation to load
     * @return The animator object reference by the specified id
     * @throws android.content.res.Resources.NotFoundException when the animation cannot be loaded
     */
    public static Animator loadAnimator(Context context, @AnimatorRes int id)
            throws NotFoundException {
        return loadAnimator(context.getResources(), context.getTheme(), id);
    }

    
Loads an Animator object from a resource 
Params:
resources – The resources
theme – The theme
id – The resource id of the animation to load
Throws:
NotFoundException – when the animation cannot be loaded
Returns:
The animator object reference by the specified id
@hide
/**
     * Loads an {@link Animator} object from a resource
     *
     * @param resources The resources
     * @param theme The theme
     * @param id The resource id of the animation to load
     * @return The animator object reference by the specified id
     * @throws android.content.res.Resources.NotFoundException when the animation cannot be loaded
     * @hide
     */
    public static Animator loadAnimator(Resources resources, Theme theme, int id)
            throws NotFoundException {
        return loadAnimator(resources, theme, id, 1);
    }

    
@hide
/** @hide */
    public static Animator loadAnimator(Resources resources, Theme theme, int id,
            float pathErrorScale) throws NotFoundException {
        final ConfigurationBoundResourceCache<Animator> animatorCache = resources
                .getAnimatorCache();
        Animator animator = animatorCache.getInstance(id, resources, theme);
        if (animator != null) {
            if (DBG_ANIMATOR_INFLATER) {
                Log.d(TAG, "loaded animator from cache, " + resources.getResourceName(id));
            }
            return animator;
        } else if (DBG_ANIMATOR_INFLATER) {
            Log.d(TAG, "cache miss for animator " + resources.getResourceName(id));
        }
        XmlResourceParser parser = null;
        try {
            parser = resources.getAnimation(id);
            animator = createAnimatorFromXml(resources, theme, parser, pathErrorScale);
            if (animator != null) {
                animator.appendChangingConfigurations(getChangingConfigs(resources, id));
                final ConstantState<Animator> constantState = animator.createConstantState();
                if (constantState != null) {
                    if (DBG_ANIMATOR_INFLATER) {
                        Log.d(TAG, "caching animator for res " + resources.getResourceName(id));
                    }
                    animatorCache.put(id, theme, constantState);
                    // create a new animator so that cached version is never used by the user
                    animator = constantState.newInstance(resources, theme);
                }
            }
            return animator;
        } catch (XmlPullParserException ex) {
            Resources.NotFoundException rnf =
                    new Resources.NotFoundException("Can't load animation resource ID #0x" +
                            Integer.toHexString(id));
            rnf.initCause(ex);
            throw rnf;
        } catch (IOException ex) {
            Resources.NotFoundException rnf =
                    new Resources.NotFoundException("Can't load animation resource ID #0x" +
                            Integer.toHexString(id));
            rnf.initCause(ex);
            throw rnf;
        } finally {
            if (parser != null) parser.close();
        }
    }

    public static StateListAnimator loadStateListAnimator(Context context, int id)
            throws NotFoundException {
        final Resources resources = context.getResources();
        final ConfigurationBoundResourceCache<StateListAnimator> cache = resources
                .getStateListAnimatorCache();
        final Theme theme = context.getTheme();
        StateListAnimator animator = cache.getInstance(id, resources, theme);
        if (animator != null) {
            return animator;
        }
        XmlResourceParser parser = null;
        try {
            parser = resources.getAnimation(id);
            animator = createStateListAnimatorFromXml(context, parser, Xml.asAttributeSet(parser));
            if (animator != null) {
                animator.appendChangingConfigurations(getChangingConfigs(resources, id));
                final ConstantState<StateListAnimator> constantState = animator
                        .createConstantState();
                if (constantState != null) {
                    cache.put(id, theme, constantState);
                    // return a clone so that the animator in constant state is never used.
                    animator = constantState.newInstance(resources, theme);
                }
            }
            return animator;
        } catch (XmlPullParserException ex) {
            Resources.NotFoundException rnf =
                    new Resources.NotFoundException(
                            "Can't load state list animator resource ID #0x" +
                                    Integer.toHexString(id)
                    );
            rnf.initCause(ex);
            throw rnf;
        } catch (IOException ex) {
            Resources.NotFoundException rnf =
                    new Resources.NotFoundException(
                            "Can't load state list animator resource ID #0x" +
                                    Integer.toHexString(id)
                    );
            rnf.initCause(ex);
            throw rnf;
        } finally {
            if (parser != null) {
                parser.close();
            }
        }
    }

    private static StateListAnimator createStateListAnimatorFromXml(Context context,
            XmlPullParser parser, AttributeSet attributeSet)
            throws IOException, XmlPullParserException {
        int type;
        StateListAnimator stateListAnimator = new StateListAnimator();

        while (true) {
            type = parser.next();
            switch (type) {
                case XmlPullParser.END_DOCUMENT:
                case XmlPullParser.END_TAG:
                    return stateListAnimator;

                case XmlPullParser.START_TAG:
                    // parse item
                    Animator animator = null;
                    if ("item".equals(parser.getName())) {
                        int attributeCount = parser.getAttributeCount();
                        int[] states = new int[attributeCount];
                        int stateIndex = 0;
                        for (int i = 0; i < attributeCount; i++) {
                            int attrName = attributeSet.getAttributeNameResource(i);
                            if (attrName == R.attr.animation) {
                                final int animId = attributeSet.getAttributeResourceValue(i, 0);
                                animator = loadAnimator(context, animId);
                            } else {
                                states[stateIndex++] =
                                        attributeSet.getAttributeBooleanValue(i, false) ?
                                                attrName : -attrName;
                            }
                        }
                        if (animator == null) {
                            animator = createAnimatorFromXml(context.getResources(),
                                    context.getTheme(), parser, 1f);
                        }

                        if (animator == null) {
                            throw new Resources.NotFoundException(
                                    "animation state item must have a valid animation");
                        }
                        stateListAnimator
                                .addState(StateSet.trimStateSet(states, stateIndex), animator);
                    }
                    break;
            }
        }
    }

    
PathDataEvaluator is used to interpolate between two paths which are
represented in the same format but different control points' values.
The path is represented as verbs and points for each of the verbs.
/**
     * PathDataEvaluator is used to interpolate between two paths which are
     * represented in the same format but different control points' values.
     * The path is represented as verbs and points for each of the verbs.
     */
    private static class PathDataEvaluator implements TypeEvaluator<PathParser.PathData> {
        private final PathParser.PathData mPathData = new PathParser.PathData();

        @Override
        public PathParser.PathData evaluate(float fraction, PathParser.PathData startPathData,
                    PathParser.PathData endPathData) {
            if (!PathParser.interpolatePathData(mPathData, startPathData, endPathData, fraction)) {
                throw new IllegalArgumentException("Can't interpolate between"
                        + " two incompatible pathData");
            }
            return mPathData;
        }
    }

    private static PropertyValuesHolder getPVH(TypedArray styledAttributes, int valueType,
            int valueFromId, int valueToId, String propertyName) {

        TypedValue tvFrom = styledAttributes.peekValue(valueFromId);
        boolean hasFrom = (tvFrom != null);
        int fromType = hasFrom ? tvFrom.type : 0;
        TypedValue tvTo = styledAttributes.peekValue(valueToId);
        boolean hasTo = (tvTo != null);
        int toType = hasTo ? tvTo.type : 0;

        if (valueType == VALUE_TYPE_UNDEFINED) {
            // Check whether it's color type. If not, fall back to default type (i.e. float type)
            if ((hasFrom && isColorType(fromType)) || (hasTo && isColorType(toType))) {
                valueType = VALUE_TYPE_COLOR;
            } else {
                valueType = VALUE_TYPE_FLOAT;
            }
        }

        boolean getFloats = (valueType == VALUE_TYPE_FLOAT);

        PropertyValuesHolder returnValue = null;

        if (valueType == VALUE_TYPE_PATH) {
            String fromString = styledAttributes.getString(valueFromId);
            String toString = styledAttributes.getString(valueToId);
            PathParser.PathData nodesFrom = fromString == null
                    ? null : new PathParser.PathData(fromString);
            PathParser.PathData nodesTo = toString == null
                    ? null : new PathParser.PathData(toString);

            if (nodesFrom != null || nodesTo != null) {
                if (nodesFrom != null) {
                    TypeEvaluator evaluator = new PathDataEvaluator();
                    if (nodesTo != null) {
                        if (!PathParser.canMorph(nodesFrom, nodesTo)) {
                            throw new InflateException(" Can't morph from " + fromString + " to " +
                                    toString);
                        }
                        returnValue = PropertyValuesHolder.ofObject(propertyName, evaluator,
                                nodesFrom, nodesTo);
                    } else {
                        returnValue = PropertyValuesHolder.ofObject(propertyName, evaluator,
                                (Object) nodesFrom);
                    }
                } else if (nodesTo != null) {
                    TypeEvaluator evaluator = new PathDataEvaluator();
                    returnValue = PropertyValuesHolder.ofObject(propertyName, evaluator,
                            (Object) nodesTo);
                }
            }
        } else {
            TypeEvaluator evaluator = null;
            // Integer and float value types are handled here.
            if (valueType == VALUE_TYPE_COLOR) {
                // special case for colors: ignore valueType and get ints
                evaluator = ArgbEvaluator.getInstance();
            }
            if (getFloats) {
                float valueFrom;
                float valueTo;
                if (hasFrom) {
                    if (fromType == TypedValue.TYPE_DIMENSION) {
                        valueFrom = styledAttributes.getDimension(valueFromId, 0f);
                    } else {
                        valueFrom = styledAttributes.getFloat(valueFromId, 0f);
                    }
                    if (hasTo) {
                        if (toType == TypedValue.TYPE_DIMENSION) {
                            valueTo = styledAttributes.getDimension(valueToId, 0f);
                        } else {
                            valueTo = styledAttributes.getFloat(valueToId, 0f);
                        }
                        returnValue = PropertyValuesHolder.ofFloat(propertyName,
                                valueFrom, valueTo);
                    } else {
                        returnValue = PropertyValuesHolder.ofFloat(propertyName, valueFrom);
                    }
                } else {
                    if (toType == TypedValue.TYPE_DIMENSION) {
                        valueTo = styledAttributes.getDimension(valueToId, 0f);
                    } else {
                        valueTo = styledAttributes.getFloat(valueToId, 0f);
                    }
                    returnValue = PropertyValuesHolder.ofFloat(propertyName, valueTo);
                }
            } else {
                int valueFrom;
                int valueTo;
                if (hasFrom) {
                    if (fromType == TypedValue.TYPE_DIMENSION) {
                        valueFrom = (int) styledAttributes.getDimension(valueFromId, 0f);
                    } else if (isColorType(fromType)) {
                        valueFrom = styledAttributes.getColor(valueFromId, 0);
                    } else {
                        valueFrom = styledAttributes.getInt(valueFromId, 0);
                    }
                    if (hasTo) {
                        if (toType == TypedValue.TYPE_DIMENSION) {
                            valueTo = (int) styledAttributes.getDimension(valueToId, 0f);
                        } else if (isColorType(toType)) {
                            valueTo = styledAttributes.getColor(valueToId, 0);
                        } else {
                            valueTo = styledAttributes.getInt(valueToId, 0);
                        }
                        returnValue = PropertyValuesHolder.ofInt(propertyName, valueFrom, valueTo);
                    } else {
                        returnValue = PropertyValuesHolder.ofInt(propertyName, valueFrom);
                    }
                } else {
                    if (hasTo) {
                        if (toType == TypedValue.TYPE_DIMENSION) {
                            valueTo = (int) styledAttributes.getDimension(valueToId, 0f);
                        } else if (isColorType(toType)) {
                            valueTo = styledAttributes.getColor(valueToId, 0);
                        } else {
                            valueTo = styledAttributes.getInt(valueToId, 0);
                        }
                        returnValue = PropertyValuesHolder.ofInt(propertyName, valueTo);
                    }
                }
            }
            if (returnValue != null && evaluator != null) {
                returnValue.setEvaluator(evaluator);
            }
        }

        return returnValue;
    }

    
Params:
anim – The animator, must not be null
arrayAnimator – Incoming typed array for Animator's attributes.
arrayObjectAnimator – Incoming typed array for Object Animator's
           attributes.
pixelSize – The relative pixel size, used to calculate the
                 maximum error for path animations./**
     * @param anim The animator, must not be null
     * @param arrayAnimator Incoming typed array for Animator's attributes.
     * @param arrayObjectAnimator Incoming typed array for Object Animator's
     *            attributes.
     * @param pixelSize The relative pixel size, used to calculate the
     *                  maximum error for path animations.
     */
    private static void parseAnimatorFromTypeArray(ValueAnimator anim,
            TypedArray arrayAnimator, TypedArray arrayObjectAnimator, float pixelSize) {
        long duration = arrayAnimator.getInt(R.styleable.Animator_duration, 300);

        long startDelay = arrayAnimator.getInt(R.styleable.Animator_startOffset, 0);

        int valueType = arrayAnimator.getInt(R.styleable.Animator_valueType, VALUE_TYPE_UNDEFINED);

        if (valueType == VALUE_TYPE_UNDEFINED) {
            valueType = inferValueTypeFromValues(arrayAnimator, R.styleable.Animator_valueFrom,
                    R.styleable.Animator_valueTo);
        }
        PropertyValuesHolder pvh = getPVH(arrayAnimator, valueType,
                R.styleable.Animator_valueFrom, R.styleable.Animator_valueTo, "");
        if (pvh != null) {
            anim.setValues(pvh);
        }

        anim.setDuration(duration);
        anim.setStartDelay(startDelay);

        if (arrayAnimator.hasValue(R.styleable.Animator_repeatCount)) {
            anim.setRepeatCount(
                    arrayAnimator.getInt(R.styleable.Animator_repeatCount, 0));
        }
        if (arrayAnimator.hasValue(R.styleable.Animator_repeatMode)) {
            anim.setRepeatMode(
                    arrayAnimator.getInt(R.styleable.Animator_repeatMode,
                            ValueAnimator.RESTART));
        }

        if (arrayObjectAnimator != null) {
            setupObjectAnimator(anim, arrayObjectAnimator, valueType, pixelSize);
        }
    }

    
Setup the Animator to achieve path morphing.
Params:
anim – The target Animator which will be updated.
arrayAnimator – TypedArray for the ValueAnimator.
Returns:
the PathDataEvaluator./**
     * Setup the Animator to achieve path morphing.
     *
     * @param anim The target Animator which will be updated.
     * @param arrayAnimator TypedArray for the ValueAnimator.
     * @return the PathDataEvaluator.
     */
    private static TypeEvaluator setupAnimatorForPath(ValueAnimator anim,
             TypedArray arrayAnimator) {
        TypeEvaluator evaluator = null;
        String fromString = arrayAnimator.getString(R.styleable.Animator_valueFrom);
        String toString = arrayAnimator.getString(R.styleable.Animator_valueTo);
        PathParser.PathData pathDataFrom = fromString == null
                ? null : new PathParser.PathData(fromString);
        PathParser.PathData pathDataTo = toString == null
                ? null : new PathParser.PathData(toString);

        if (pathDataFrom != null) {
            if (pathDataTo != null) {
                anim.setObjectValues(pathDataFrom, pathDataTo);
                if (!PathParser.canMorph(pathDataFrom, pathDataTo)) {
                    throw new InflateException(arrayAnimator.getPositionDescription()
                            + " Can't morph from " + fromString + " to " + toString);
                }
            } else {
                anim.setObjectValues((Object)pathDataFrom);
            }
            evaluator = new PathDataEvaluator();
        } else if (pathDataTo != null) {
            anim.setObjectValues((Object)pathDataTo);
            evaluator = new PathDataEvaluator();
        }

        if (DBG_ANIMATOR_INFLATER && evaluator != null) {
            Log.v(TAG, "create a new PathDataEvaluator here");
        }

        return evaluator;
    }

    
Setup ObjectAnimator's property or values from pathData.
Params:
anim – The target Animator which will be updated.
arrayObjectAnimator – TypedArray for the ObjectAnimator.
getFloats – True if the value type is float.
pixelSize – The relative pixel size, used to calculate the
                 maximum error for path animations./**
     * Setup ObjectAnimator's property or values from pathData.
     *
     * @param anim The target Animator which will be updated.
     * @param arrayObjectAnimator TypedArray for the ObjectAnimator.
     * @param getFloats True if the value type is float.
     * @param pixelSize The relative pixel size, used to calculate the
     *                  maximum error for path animations.
     */
    private static void setupObjectAnimator(ValueAnimator anim, TypedArray arrayObjectAnimator,
            int valueType, float pixelSize) {
        ObjectAnimator oa = (ObjectAnimator) anim;
        String pathData = arrayObjectAnimator.getString(R.styleable.PropertyAnimator_pathData);

        // Path can be involved in an ObjectAnimator in the following 3 ways:
        // 1) Path morphing: the property to be animated is pathData, and valueFrom and valueTo
        //    are both of pathType. valueType = pathType needs to be explicitly defined.
        // 2) A property in X or Y dimension can be animated along a path: the property needs to be
        //    defined in propertyXName or propertyYName attribute, the path will be defined in the
        //    pathData attribute. valueFrom and valueTo will not be necessary for this animation.
        // 3) PathInterpolator can also define a path (in pathData) for its interpolation curve.
        // Here we are dealing with case 2:
        if (pathData != null) {
            String propertyXName =
                    arrayObjectAnimator.getString(R.styleable.PropertyAnimator_propertyXName);
            String propertyYName =
                    arrayObjectAnimator.getString(R.styleable.PropertyAnimator_propertyYName);

            if (valueType == VALUE_TYPE_PATH || valueType == VALUE_TYPE_UNDEFINED) {
                // When pathData is defined, we are in case #2 mentioned above. ValueType can only
                // be float type, or int type. Otherwise we fallback to default type.
                valueType = VALUE_TYPE_FLOAT;
            }
            if (propertyXName == null && propertyYName == null) {
                throw new InflateException(arrayObjectAnimator.getPositionDescription()
                        + " propertyXName or propertyYName is needed for PathData");
            } else {
                Path path = PathParser.createPathFromPathData(pathData);
                float error = 0.5f * pixelSize; // max half a pixel error
                PathKeyframes keyframeSet = KeyframeSet.ofPath(path, error);
                Keyframes xKeyframes;
                Keyframes yKeyframes;
                if (valueType == VALUE_TYPE_FLOAT) {
                    xKeyframes = keyframeSet.createXFloatKeyframes();
                    yKeyframes = keyframeSet.createYFloatKeyframes();
                } else {
                    xKeyframes = keyframeSet.createXIntKeyframes();
                    yKeyframes = keyframeSet.createYIntKeyframes();
                }
                PropertyValuesHolder x = null;
                PropertyValuesHolder y = null;
                if (propertyXName != null) {
                    x = PropertyValuesHolder.ofKeyframes(propertyXName, xKeyframes);
                }
                if (propertyYName != null) {
                    y = PropertyValuesHolder.ofKeyframes(propertyYName, yKeyframes);
                }
                if (x == null) {
                    oa.setValues(y);
                } else if (y == null) {
                    oa.setValues(x);
                } else {
                    oa.setValues(x, y);
                }
            }
        } else {
            String propertyName =
                    arrayObjectAnimator.getString(R.styleable.PropertyAnimator_propertyName);
            oa.setPropertyName(propertyName);
        }
    }

    
Setup ValueAnimator's values.
This will handle all of the integer, float and color types.
Params:
anim – The target Animator which will be updated.
arrayAnimator – TypedArray for the ValueAnimator.
getFloats – True if the value type is float.
hasFrom – True if "valueFrom" exists.
fromType – The type of "valueFrom".
hasTo – True if "valueTo" exists.
toType – The type of "valueTo"./**
     * Setup ValueAnimator's values.
     * This will handle all of the integer, float and color types.
     *
     * @param anim The target Animator which will be updated.
     * @param arrayAnimator TypedArray for the ValueAnimator.
     * @param getFloats True if the value type is float.
     * @param hasFrom True if "valueFrom" exists.
     * @param fromType The type of "valueFrom".
     * @param hasTo True if "valueTo" exists.
     * @param toType The type of "valueTo".
     */
    private static void setupValues(ValueAnimator anim, TypedArray arrayAnimator,
            boolean getFloats, boolean hasFrom, int fromType, boolean hasTo, int toType) {
        int valueFromIndex = R.styleable.Animator_valueFrom;
        int valueToIndex = R.styleable.Animator_valueTo;
        if (getFloats) {
            float valueFrom;
            float valueTo;
            if (hasFrom) {
                if (fromType == TypedValue.TYPE_DIMENSION) {
                    valueFrom = arrayAnimator.getDimension(valueFromIndex, 0f);
                } else {
                    valueFrom = arrayAnimator.getFloat(valueFromIndex, 0f);
                }
                if (hasTo) {
                    if (toType == TypedValue.TYPE_DIMENSION) {
                        valueTo = arrayAnimator.getDimension(valueToIndex, 0f);
                    } else {
                        valueTo = arrayAnimator.getFloat(valueToIndex, 0f);
                    }
                    anim.setFloatValues(valueFrom, valueTo);
                } else {
                    anim.setFloatValues(valueFrom);
                }
            } else {
                if (toType == TypedValue.TYPE_DIMENSION) {
                    valueTo = arrayAnimator.getDimension(valueToIndex, 0f);
                } else {
                    valueTo = arrayAnimator.getFloat(valueToIndex, 0f);
                }
                anim.setFloatValues(valueTo);
            }
        } else {
            int valueFrom;
            int valueTo;
            if (hasFrom) {
                if (fromType == TypedValue.TYPE_DIMENSION) {
                    valueFrom = (int) arrayAnimator.getDimension(valueFromIndex, 0f);
                } else if (isColorType(fromType)) {
                    valueFrom = arrayAnimator.getColor(valueFromIndex, 0);
                } else {
                    valueFrom = arrayAnimator.getInt(valueFromIndex, 0);
                }
                if (hasTo) {
                    if (toType == TypedValue.TYPE_DIMENSION) {
                        valueTo = (int) arrayAnimator.getDimension(valueToIndex, 0f);
                    } else if (isColorType(toType)) {
                        valueTo = arrayAnimator.getColor(valueToIndex, 0);
                    } else {
                        valueTo = arrayAnimator.getInt(valueToIndex, 0);
                    }
                    anim.setIntValues(valueFrom, valueTo);
                } else {
                    anim.setIntValues(valueFrom);
                }
            } else {
                if (hasTo) {
                    if (toType == TypedValue.TYPE_DIMENSION) {
                        valueTo = (int) arrayAnimator.getDimension(valueToIndex, 0f);
                    } else if (isColorType(toType)) {
                        valueTo = arrayAnimator.getColor(valueToIndex, 0);
                    } else {
                        valueTo = arrayAnimator.getInt(valueToIndex, 0);
                    }
                    anim.setIntValues(valueTo);
                }
            }
        }
    }

    private static Animator createAnimatorFromXml(Resources res, Theme theme, XmlPullParser parser,
            float pixelSize)
            throws XmlPullParserException, IOException {
        return createAnimatorFromXml(res, theme, parser, Xml.asAttributeSet(parser), null, 0,
                pixelSize);
    }

    private static Animator createAnimatorFromXml(Resources res, Theme theme, XmlPullParser parser,
            AttributeSet attrs, AnimatorSet parent, int sequenceOrdering, float pixelSize)
            throws XmlPullParserException, IOException {
        Animator anim = null;
        ArrayList<Animator> childAnims = null;

        // Make sure we are on a start tag.
        int type;
        int depth = parser.getDepth();

        while (((type = parser.next()) != XmlPullParser.END_TAG || parser.getDepth() > depth)
                && type != XmlPullParser.END_DOCUMENT) {

            if (type != XmlPullParser.START_TAG) {
                continue;
            }

            String name = parser.getName();
            boolean gotValues = false;

            if (name.equals("objectAnimator")) {
                anim = loadObjectAnimator(res, theme, attrs, pixelSize);
            } else if (name.equals("animator")) {
                anim = loadAnimator(res, theme, attrs, null, pixelSize);
            } else if (name.equals("set")) {
                anim = new AnimatorSet();
                TypedArray a;
                if (theme != null) {
                    a = theme.obtainStyledAttributes(attrs, R.styleable.AnimatorSet, 0, 0);
                } else {
                    a = res.obtainAttributes(attrs, R.styleable.AnimatorSet);
                }
                anim.appendChangingConfigurations(a.getChangingConfigurations());
                int ordering = a.getInt(R.styleable.AnimatorSet_ordering, TOGETHER);
                createAnimatorFromXml(res, theme, parser, attrs, (AnimatorSet) anim, ordering,
                        pixelSize);
                a.recycle();
            } else if (name.equals("propertyValuesHolder")) {
                PropertyValuesHolder[] values = loadValues(res, theme, parser,
                        Xml.asAttributeSet(parser));
                if (values != null && anim != null && (anim instanceof ValueAnimator)) {
                    ((ValueAnimator) anim).setValues(values);
                }
                gotValues = true;
            } else {
                throw new RuntimeException("Unknown animator name: " + parser.getName());
            }

            if (parent != null && !gotValues) {
                if (childAnims == null) {
                    childAnims = new ArrayList<Animator>();
                }
                childAnims.add(anim);
            }
        }
        if (parent != null && childAnims != null) {
            Animator[] animsArray = new Animator[childAnims.size()];
            int index = 0;
            for (Animator a : childAnims) {
                animsArray[index++] = a;
            }
            if (sequenceOrdering == TOGETHER) {
                parent.playTogether(animsArray);
            } else {
                parent.playSequentially(animsArray);
            }
        }
        return anim;
    }

    private static PropertyValuesHolder[] loadValues(Resources res, Theme theme,
            XmlPullParser parser, AttributeSet attrs) throws XmlPullParserException, IOException {
        ArrayList<PropertyValuesHolder> values = null;

        int type;
        while ((type = parser.getEventType()) != XmlPullParser.END_TAG &&
                type != XmlPullParser.END_DOCUMENT) {

            if (type != XmlPullParser.START_TAG) {
                parser.next();
                continue;
            }

            String name = parser.getName();

            if (name.equals("propertyValuesHolder")) {
                TypedArray a;
                if (theme != null) {
                    a = theme.obtainStyledAttributes(attrs, R.styleable.PropertyValuesHolder, 0, 0);
                } else {
                    a = res.obtainAttributes(attrs, R.styleable.PropertyValuesHolder);
                }
                String propertyName = a.getString(R.styleable.PropertyValuesHolder_propertyName);
                int valueType = a.getInt(R.styleable.PropertyValuesHolder_valueType,
                        VALUE_TYPE_UNDEFINED);

                PropertyValuesHolder pvh = loadPvh(res, theme, parser, propertyName, valueType);
                if (pvh == null) {
                    pvh = getPVH(a, valueType,
                            R.styleable.PropertyValuesHolder_valueFrom,
                            R.styleable.PropertyValuesHolder_valueTo, propertyName);
                }
                if (pvh != null) {
                    if (values == null) {
                        values = new ArrayList<PropertyValuesHolder>();
                    }
                    values.add(pvh);
                }
                a.recycle();
            }

            parser.next();
        }

        PropertyValuesHolder[] valuesArray = null;
        if (values != null) {
            int count = values.size();
            valuesArray = new PropertyValuesHolder[count];
            for (int i = 0; i < count; ++i) {
                valuesArray[i] = values.get(i);
            }
        }
        return valuesArray;
    }

    // When no value type is provided in keyframe, we need to infer the type from the value. i.e.
    // if value is defined in the style of a color value, then the color type is returned.
    // Otherwise, default float type is returned.
    private static int inferValueTypeOfKeyframe(Resources res, Theme theme, AttributeSet attrs) {
        int valueType;
        TypedArray a;
        if (theme != null) {
            a = theme.obtainStyledAttributes(attrs, R.styleable.Keyframe, 0, 0);
        } else {
            a = res.obtainAttributes(attrs, R.styleable.Keyframe);
        }

        TypedValue keyframeValue = a.peekValue(R.styleable.Keyframe_value);
        boolean hasValue = (keyframeValue != null);
        // When no value type is provided, check whether it's a color type first.
        // If not, fall back to default value type (i.e. float type).
        if (hasValue && isColorType(keyframeValue.type)) {
            valueType = VALUE_TYPE_COLOR;
        } else {
            valueType = VALUE_TYPE_FLOAT;
        }
        a.recycle();
        return valueType;
    }

    private static int inferValueTypeFromValues(TypedArray styledAttributes, int valueFromId,
            int valueToId) {
        TypedValue tvFrom = styledAttributes.peekValue(valueFromId);
        boolean hasFrom = (tvFrom != null);
        int fromType = hasFrom ? tvFrom.type : 0;
        TypedValue tvTo = styledAttributes.peekValue(valueToId);
        boolean hasTo = (tvTo != null);
        int toType = hasTo ? tvTo.type : 0;

        int valueType;
        // Check whether it's color type. If not, fall back to default type (i.e. float type)
        if ((hasFrom && isColorType(fromType)) || (hasTo && isColorType(toType))) {
            valueType = VALUE_TYPE_COLOR;
        } else {
            valueType = VALUE_TYPE_FLOAT;
        }
        return valueType;
    }

    private static void dumpKeyframes(Object[] keyframes, String header) {
        if (keyframes == null || keyframes.length == 0) {
            return;
        }
        Log.d(TAG, header);
        int count = keyframes.length;
        for (int i = 0; i < count; ++i) {
            Keyframe keyframe = (Keyframe) keyframes[i];
            Log.d(TAG, "Keyframe " + i + ": fraction " +
                    (keyframe.getFraction() < 0 ? "null" : keyframe.getFraction()) + ", " +
                    ", value : " + ((keyframe.hasValue()) ? keyframe.getValue() : "null"));
        }
    }

    // Load property values holder if there are keyframes defined in it. Otherwise return null.
    private static PropertyValuesHolder loadPvh(Resources res, Theme theme, XmlPullParser parser,
            String propertyName, int valueType)
            throws XmlPullParserException, IOException {

        PropertyValuesHolder value = null;
        ArrayList<Keyframe> keyframes = null;

        int type;
        while ((type = parser.next()) != XmlPullParser.END_TAG &&
                type != XmlPullParser.END_DOCUMENT) {
            String name = parser.getName();
            if (name.equals("keyframe")) {
                if (valueType == VALUE_TYPE_UNDEFINED) {
                    valueType = inferValueTypeOfKeyframe(res, theme, Xml.asAttributeSet(parser));
                }
                Keyframe keyframe = loadKeyframe(res, theme, Xml.asAttributeSet(parser), valueType);
                if (keyframe != null) {
                    if (keyframes == null) {
                        keyframes = new ArrayList<Keyframe>();
                    }
                    keyframes.add(keyframe);
                }
                parser.next();
            }
        }

        int count;
        if (keyframes != null && (count = keyframes.size()) > 0) {
            // make sure we have keyframes at 0 and 1
            // If we have keyframes with set fractions, add keyframes at start/end
            // appropriately. If start/end have no set fractions:
            // if there's only one keyframe, set its fraction to 1 and add one at 0
            // if >1 keyframe, set the last fraction to 1, the first fraction to 0
            Keyframe firstKeyframe = keyframes.get(0);
            Keyframe lastKeyframe = keyframes.get(count - 1);
            float endFraction = lastKeyframe.getFraction();
            if (endFraction < 1) {
                if (endFraction < 0) {
                    lastKeyframe.setFraction(1);
                } else {
                    keyframes.add(keyframes.size(), createNewKeyframe(lastKeyframe, 1));
                    ++count;
                }
            }
            float startFraction = firstKeyframe.getFraction();
            if (startFraction != 0) {
                if (startFraction < 0) {
                    firstKeyframe.setFraction(0);
                } else {
                    keyframes.add(0, createNewKeyframe(firstKeyframe, 0));
                    ++count;
                }
            }
            Keyframe[] keyframeArray = new Keyframe[count];
            keyframes.toArray(keyframeArray);
            for (int i = 0; i < count; ++i) {
                Keyframe keyframe = keyframeArray[i];
                if (keyframe.getFraction() < 0) {
                    if (i == 0) {
                        keyframe.setFraction(0);
                    } else if (i == count - 1) {
                        keyframe.setFraction(1);
                    } else {
                        // figure out the start/end parameters of the current gap
                        // in fractions and distribute the gap among those keyframes
                        int startIndex = i;
                        int endIndex = i;
                        for (int j = startIndex + 1; j < count - 1; ++j) {
                            if (keyframeArray[j].getFraction() >= 0) {
                                break;
                            }
                            endIndex = j;
                        }
                        float gap = keyframeArray[endIndex + 1].getFraction() -
                                keyframeArray[startIndex - 1].getFraction();
                        distributeKeyframes(keyframeArray, gap, startIndex, endIndex);
                    }
                }
            }
            value = PropertyValuesHolder.ofKeyframe(propertyName, keyframeArray);
            if (valueType == VALUE_TYPE_COLOR) {
                value.setEvaluator(ArgbEvaluator.getInstance());
            }
        }

        return value;
    }

    private static Keyframe createNewKeyframe(Keyframe sampleKeyframe, float fraction) {
        return sampleKeyframe.getType() == float.class ?
                            Keyframe.ofFloat(fraction) :
                            (sampleKeyframe.getType() == int.class) ?
                                    Keyframe.ofInt(fraction) :
                                    Keyframe.ofObject(fraction);
    }

    
Utility function to set fractions on keyframes to cover a gap in which the
fractions are not currently set. Keyframe fractions will be distributed evenly
in this gap. For example, a gap of 1 keyframe in the range 0-1 will be at .5, a gap
of .6 spread between two keyframes will be at .2 and .4 beyond the fraction at the
keyframe before startIndex.
Assumptions:
- First and last keyframe fractions (bounding this spread) are already set. So,
for example, if no fractions are set, we will already set first and last keyframe
fraction values to 0 and 1.
- startIndex must be >0 (which follows from first assumption).
- endIndex must be >= startIndex.
Params:
keyframes – the array of keyframes
gap – The total gap we need to distribute
startIndex – The index of the first keyframe whose fraction must be set
endIndex – The index of the last keyframe whose fraction must be set/**
     * Utility function to set fractions on keyframes to cover a gap in which the
     * fractions are not currently set. Keyframe fractions will be distributed evenly
     * in this gap. For example, a gap of 1 keyframe in the range 0-1 will be at .5, a gap
     * of .6 spread between two keyframes will be at .2 and .4 beyond the fraction at the
     * keyframe before startIndex.
     * Assumptions:
     * - First and last keyframe fractions (bounding this spread) are already set. So,
     * for example, if no fractions are set, we will already set first and last keyframe
     * fraction values to 0 and 1.
     * - startIndex must be >0 (which follows from first assumption).
     * - endIndex must be >= startIndex.
     *
     * @param keyframes the array of keyframes
     * @param gap The total gap we need to distribute
     * @param startIndex The index of the first keyframe whose fraction must be set
     * @param endIndex The index of the last keyframe whose fraction must be set
     */
    private static void distributeKeyframes(Keyframe[] keyframes, float gap,
            int startIndex, int endIndex) {
        int count = endIndex - startIndex + 2;
        float increment = gap / count;
        for (int i = startIndex; i <= endIndex; ++i) {
            keyframes[i].setFraction(keyframes[i-1].getFraction() + increment);
        }
    }

    private static Keyframe loadKeyframe(Resources res, Theme theme, AttributeSet attrs,
            int valueType)
            throws XmlPullParserException, IOException {

        TypedArray a;
        if (theme != null) {
            a = theme.obtainStyledAttributes(attrs, R.styleable.Keyframe, 0, 0);
        } else {
            a = res.obtainAttributes(attrs, R.styleable.Keyframe);
        }

        Keyframe keyframe = null;

        float fraction = a.getFloat(R.styleable.Keyframe_fraction, -1);

        TypedValue keyframeValue = a.peekValue(R.styleable.Keyframe_value);
        boolean hasValue = (keyframeValue != null);
        if (valueType == VALUE_TYPE_UNDEFINED) {
            // When no value type is provided, check whether it's a color type first.
            // If not, fall back to default value type (i.e. float type).
            if (hasValue && isColorType(keyframeValue.type)) {
                valueType = VALUE_TYPE_COLOR;
            } else {
                valueType = VALUE_TYPE_FLOAT;
            }
        }

        if (hasValue) {
            switch (valueType) {
                case VALUE_TYPE_FLOAT:
                    float value = a.getFloat(R.styleable.Keyframe_value, 0);
                    keyframe = Keyframe.ofFloat(fraction, value);
                    break;
                case VALUE_TYPE_COLOR:
                case VALUE_TYPE_INT:
                    int intValue = a.getInt(R.styleable.Keyframe_value, 0);
                    keyframe = Keyframe.ofInt(fraction, intValue);
                    break;
            }
        } else {
            keyframe = (valueType == VALUE_TYPE_FLOAT) ? Keyframe.ofFloat(fraction) :
                    Keyframe.ofInt(fraction);
        }

        final int resID = a.getResourceId(R.styleable.Keyframe_interpolator, 0);
        if (resID > 0) {
            final Interpolator interpolator = AnimationUtils.loadInterpolator(res, theme, resID);
            keyframe.setInterpolator(interpolator);
        }
        a.recycle();

        return keyframe;
    }

    private static ObjectAnimator loadObjectAnimator(Resources res, Theme theme, AttributeSet attrs,
            float pathErrorScale) throws NotFoundException {
        ObjectAnimator anim = new ObjectAnimator();

        loadAnimator(res, theme, attrs, anim, pathErrorScale);

        return anim;
    }

    
Creates a new animation whose parameters come from the specified context
and attributes set.
Params:
res – The resources
attrs – The set of attributes holding the animation parameters
anim – Null if this is a ValueAnimator, otherwise this is an
           ObjectAnimator/**
     * Creates a new animation whose parameters come from the specified context
     * and attributes set.
     *
     * @param res The resources
     * @param attrs The set of attributes holding the animation parameters
     * @param anim Null if this is a ValueAnimator, otherwise this is an
     *            ObjectAnimator
     */
    private static ValueAnimator loadAnimator(Resources res, Theme theme,
            AttributeSet attrs, ValueAnimator anim, float pathErrorScale)
            throws NotFoundException {
        TypedArray arrayAnimator = null;
        TypedArray arrayObjectAnimator = null;

        if (theme != null) {
            arrayAnimator = theme.obtainStyledAttributes(attrs, R.styleable.Animator, 0, 0);
        } else {
            arrayAnimator = res.obtainAttributes(attrs, R.styleable.Animator);
        }

        // If anim is not null, then it is an object animator.
        if (anim != null) {
            if (theme != null) {
                arrayObjectAnimator = theme.obtainStyledAttributes(attrs,
                        R.styleable.PropertyAnimator, 0, 0);
            } else {
                arrayObjectAnimator = res.obtainAttributes(attrs, R.styleable.PropertyAnimator);
            }
            anim.appendChangingConfigurations(arrayObjectAnimator.getChangingConfigurations());
        }

        if (anim == null) {
            anim = new ValueAnimator();
        }
        anim.appendChangingConfigurations(arrayAnimator.getChangingConfigurations());

        parseAnimatorFromTypeArray(anim, arrayAnimator, arrayObjectAnimator, pathErrorScale);

        final int resID = arrayAnimator.getResourceId(R.styleable.Animator_interpolator, 0);
        if (resID > 0) {
            final Interpolator interpolator = AnimationUtils.loadInterpolator(res, theme, resID);
            if (interpolator instanceof BaseInterpolator) {
                anim.appendChangingConfigurations(
                        ((BaseInterpolator) interpolator).getChangingConfiguration());
            }
            anim.setInterpolator(interpolator);
        }

        arrayAnimator.recycle();
        if (arrayObjectAnimator != null) {
            arrayObjectAnimator.recycle();
        }
        return anim;
    }

    private static @Config int getChangingConfigs(@NonNull Resources resources, @AnyRes int id) {
        synchronized (sTmpTypedValue) {
            resources.getValue(id, sTmpTypedValue, true);
            return sTmpTypedValue.changingConfigurations;
        }
    }

    private static boolean isColorType(int type) {
       return (type >= TypedValue.TYPE_FIRST_COLOR_INT) && (type <= TypedValue.TYPE_LAST_COLOR_INT);
    }
}