content: /*
   * 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 com.actionbarsherlock.internal.nineoldandroids.animation;
  
  import java.util.ArrayList;
  import java.util.Arrays;
  import android.view.animation.Interpolator;
  
  import com.actionbarsherlock.internal.nineoldandroids.animation.Keyframe.FloatKeyframe;
  import com.actionbarsherlock.internal.nineoldandroids.animation.Keyframe.IntKeyframe;
  import com.actionbarsherlock.internal.nineoldandroids.animation.Keyframe.ObjectKeyframe;
  
  /**
   * This class holds a collection of Keyframe objects and is called by ValueAnimator to calculate
   * values between those keyframes for a given animation. The class internal to the animation
   * package because it is an implementation detail of how Keyframes are stored and used.
   */
  @SuppressWarnings({"rawtypes", "unchecked"})
  class KeyframeSet {
  
      int mNumKeyframes;
  
      Keyframe mFirstKeyframe;
      Keyframe mLastKeyframe;
      /*Time*/Interpolator mInterpolator; // only used in the 2-keyframe case
      ArrayList<Keyframe> mKeyframes; // only used when there are not 2 keyframes
      TypeEvaluator mEvaluator;
  
  
      public KeyframeSet(Keyframe... keyframes) {
          mNumKeyframes = keyframes.length;
          mKeyframes = new ArrayList<Keyframe>();
          mKeyframes.addAll(Arrays.asList(keyframes));
          mFirstKeyframe = mKeyframes.get(0);
          mLastKeyframe = mKeyframes.get(mNumKeyframes - 1);
          mInterpolator = mLastKeyframe.getInterpolator();
      }
  
      public static KeyframeSet ofInt(int... values) {
          int numKeyframes = values.length;
          IntKeyframe keyframes[] = new IntKeyframe[Math.max(numKeyframes,2)];
          if (numKeyframes == 1) {
              keyframes[0] = (IntKeyframe) Keyframe.ofInt(0f);
              keyframes[1] = (IntKeyframe) Keyframe.ofInt(1f, values[0]);
          } else {
              keyframes[0] = (IntKeyframe) Keyframe.ofInt(0f, values[0]);
              for (int i = 1; i < numKeyframes; ++i) {
                  keyframes[i] = (IntKeyframe) Keyframe.ofInt((float) i / (numKeyframes - 1), values[i]);
              }
          }
          return new IntKeyframeSet(keyframes);
      }
  
      public static KeyframeSet ofFloat(float... values) {
          int numKeyframes = values.length;
          FloatKeyframe keyframes[] = new FloatKeyframe[Math.max(numKeyframes,2)];
          if (numKeyframes == 1) {
              keyframes[0] = (FloatKeyframe) Keyframe.ofFloat(0f);
              keyframes[1] = (FloatKeyframe) Keyframe.ofFloat(1f, values[0]);
          } else {
              keyframes[0] = (FloatKeyframe) Keyframe.ofFloat(0f, values[0]);
              for (int i = 1; i < numKeyframes; ++i) {
                  keyframes[i] = (FloatKeyframe) Keyframe.ofFloat((float) i / (numKeyframes - 1), values[i]);
              }
          }
          return new FloatKeyframeSet(keyframes);
      }
  
      public static KeyframeSet ofKeyframe(Keyframe... keyframes) {
          // if all keyframes of same primitive type, create the appropriate KeyframeSet
          int numKeyframes = keyframes.length;
          boolean hasFloat = false;
          boolean hasInt = false;
          boolean hasOther = false;
          for (int i = 0; i < numKeyframes; ++i) {
              if (keyframes[i] instanceof FloatKeyframe) {
                  hasFloat = true;
              } else if (keyframes[i] instanceof IntKeyframe) {
                  hasInt = true;
              } else {
                  hasOther = true;
              }
          }
          if (hasFloat && !hasInt && !hasOther) {
              FloatKeyframe floatKeyframes[] = new FloatKeyframe[numKeyframes];
              for (int i = 0; i < numKeyframes; ++i) {
                  floatKeyframes[i] = (FloatKeyframe) keyframes[i];
              }
              return new FloatKeyframeSet(floatKeyframes);
          } else if (hasInt && !hasFloat && !hasOther) {
              IntKeyframe intKeyframes[] = new IntKeyframe[numKeyframes];
              for (int i = 0; i < numKeyframes; ++i) {
                  intKeyframes[i] = (IntKeyframe) keyframes[i];
              }
              return new IntKeyframeSet(intKeyframes);
          } else {
              return new KeyframeSet(keyframes);
          }
      }
  
      public static KeyframeSet ofObject(Object... values) {
          int numKeyframes = values.length;
          ObjectKeyframe keyframes[] = new ObjectKeyframe[Math.max(numKeyframes,2)];
          if (numKeyframes == 1) {
              keyframes[0] = (ObjectKeyframe) Keyframe.ofObject(0f);
              keyframes[1] = (ObjectKeyframe) Keyframe.ofObject(1f, values[0]);
          } else {
              keyframes[0] = (ObjectKeyframe) Keyframe.ofObject(0f, values[0]);
              for (int i = 1; i < numKeyframes; ++i) {
                  keyframes[i] = (ObjectKeyframe) Keyframe.ofObject((float) i / (numKeyframes - 1), values[i]);
              }
          }
          return new KeyframeSet(keyframes);
      }
  
      /**
       * Sets the TypeEvaluator to be used when calculating animated values. This object
       * is required only for KeyframeSets that are not either IntKeyframeSet or FloatKeyframeSet,
       * both of which assume their own evaluator to speed up calculations with those primitive
       * types.
       *
       * @param evaluator The TypeEvaluator to be used to calculate animated values.
       */
      public void setEvaluator(TypeEvaluator evaluator) {
          mEvaluator = evaluator;
      }
  
      @Override
      public KeyframeSet clone() {
          ArrayList<Keyframe> keyframes = mKeyframes;
          int numKeyframes = mKeyframes.size();
          Keyframe[] newKeyframes = new Keyframe[numKeyframes];
          for (int i = 0; i < numKeyframes; ++i) {
              newKeyframes[i] = keyframes.get(i).clone();
          }
          KeyframeSet newSet = new KeyframeSet(newKeyframes);
          return newSet;
      }
  
      /**
       * Gets the animated value, given the elapsed fraction of the animation (interpolated by the
       * animation's interpolator) and the evaluator used to calculate in-between values. This
       * function maps the input fraction to the appropriate keyframe interval and a fraction
       * between them and returns the interpolated value. Note that the input fraction may fall
       * outside the [0-1] bounds, if the animation's interpolator made that happen (e.g., a
       * spring interpolation that might send the fraction past 1.0). We handle this situation by
       * just using the two keyframes at the appropriate end when the value is outside those bounds.
       *
       * @param fraction The elapsed fraction of the animation
       * @return The animated value.
       */
      public Object getValue(float fraction) {
  
          // Special-case optimization for the common case of only two keyframes
          if (mNumKeyframes == 2) {
              if (mInterpolator != null) {
                  fraction = mInterpolator.getInterpolation(fraction);
              }
              return mEvaluator.evaluate(fraction, mFirstKeyframe.getValue(),
                      mLastKeyframe.getValue());
          }
          if (fraction <= 0f) {
              final Keyframe nextKeyframe = mKeyframes.get(1);
              final /*Time*/Interpolator interpolator = nextKeyframe.getInterpolator();
              if (interpolator != null) {
                  fraction = interpolator.getInterpolation(fraction);
              }
              final float prevFraction = mFirstKeyframe.getFraction();
              float intervalFraction = (fraction - prevFraction) /
                  (nextKeyframe.getFraction() - prevFraction);
              return mEvaluator.evaluate(intervalFraction, mFirstKeyframe.getValue(),
                      nextKeyframe.getValue());
          } else if (fraction >= 1f) {
              final Keyframe prevKeyframe = mKeyframes.get(mNumKeyframes - 2);
              final /*Time*/Interpolator interpolator = mLastKeyframe.getInterpolator();
              if (interpolator != null) {
                  fraction = interpolator.getInterpolation(fraction);
              }
              final float prevFraction = prevKeyframe.getFraction();
              float intervalFraction = (fraction - prevFraction) /
                  (mLastKeyframe.getFraction() - prevFraction);
              return mEvaluator.evaluate(intervalFraction, prevKeyframe.getValue(),
                      mLastKeyframe.getValue());
          }
          Keyframe prevKeyframe = mFirstKeyframe;
          for (int i = 1; i < mNumKeyframes; ++i) {
              Keyframe nextKeyframe = mKeyframes.get(i);
              if (fraction < nextKeyframe.getFraction()) {
                  final /*Time*/Interpolator interpolator = nextKeyframe.getInterpolator();
                  if (interpolator != null) {
                      fraction = interpolator.getInterpolation(fraction);
                  }
                  final float prevFraction = prevKeyframe.getFraction();
                  float intervalFraction = (fraction - prevFraction) /
                      (nextKeyframe.getFraction() - prevFraction);
                  return mEvaluator.evaluate(intervalFraction, prevKeyframe.getValue(),
                          nextKeyframe.getValue());
              }
              prevKeyframe = nextKeyframe;
          }
          // shouldn't reach here
          return mLastKeyframe.getValue();
      }
  
      @Override
      public String toString() {
          String returnVal = " ";
          for (int i = 0; i < mNumKeyframes; ++i) {
              returnVal += mKeyframes.get(i).getValue() + "  ";
          }
          return returnVal;
      }
  }
  