/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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.taobao.weex.ui.view.refresh.circlebar;

import android.content.Context;
import android.content.res.Resources;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.ColorFilter;
import android.graphics.Paint;
import android.graphics.Paint.Style;
import android.graphics.Path;
import android.graphics.PixelFormat;
import android.graphics.Rect;
import android.graphics.RectF;
import android.graphics.drawable.Animatable;
import android.graphics.drawable.Drawable;
import android.support.annotation.IntDef;
import android.support.annotation.NonNull;
import android.support.v4.view.animation.FastOutSlowInInterpolator;
import android.util.DisplayMetrics;
import android.view.View;
import android.view.animation.Animation;
import android.view.animation.Interpolator;
import android.view.animation.LinearInterpolator;
import android.view.animation.Transformation;

import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.util.ArrayList;

/**
 * Copy of android.support.v4
 */
class MaterialProgressDrawable extends Drawable implements Animatable {

  private static final Interpolator LINEAR_INTERPOLATOR = new LinearInterpolator();
  private static final Interpolator MATERIAL_INTERPOLATOR = new FastOutSlowInInterpolator();

  private static final float FULL_ROTATION = 1080.0f;

  @Retention(RetentionPolicy.CLASS)
  @IntDef({LARGE, DEFAULT})
  public @interface ProgressDrawableSize {

  }

  // Maps to ProgressBar.Large style
  static final int LARGE = 0;
  // Maps to ProgressBar default style
  static final int DEFAULT = 1;

  // Maps to ProgressBar default style
  private static final int CIRCLE_DIAMETER = 40;
  private static final float CENTER_RADIUS = 8.75f; //should add up to 10 when + stroke_width
  private static final float STROKE_WIDTH = 2.5f;

  // Maps to ProgressBar.Large style
  private static final int CIRCLE_DIAMETER_LARGE = 56;
  private static final float CENTER_RADIUS_LARGE = 12.5f;
  private static final float STROKE_WIDTH_LARGE = 3f;

  private final int[] COLORS = new int[]{
      Color.BLACK
  };

  /**
   * The value in the linear interpolator for animating the drawable at which
   * the color transition should start
   */
  private static final float COLOR_START_DELAY_OFFSET = 0.75f;
  private static final float END_TRIM_START_DELAY_OFFSET = 0.5f;
  private static final float START_TRIM_DURATION_OFFSET = 0.5f;

  /** The duration of a single progress spin in milliseconds. */
  private static final int ANIMATION_DURATION = 1332;

  /** The number of points in the progress "star". */
  private static final float NUM_POINTS = 5f;
  /** The list of animators operating on this drawable. */
  private final ArrayList<Animation> mAnimators = new ArrayList<Animation>();

  /** The indicator ring, used to manage animation state. */
  private final Ring mRing;

  /** Canvas rotation in degrees. */
  private float mRotation;

  /** Layout info for the arrowhead in dp */
  private static final int ARROW_WIDTH = 10;
  private static final int ARROW_HEIGHT = 5;
  private static final float ARROW_OFFSET_ANGLE = 5;

  /** Layout info for the arrowhead for the large spinner in dp */
  private static final int ARROW_WIDTH_LARGE = 12;
  private static final int ARROW_HEIGHT_LARGE = 6;
  private static final float MAX_PROGRESS_ARC = .8f;

  private Resources mResources;
  private View mParent;
  private Animation mAnimation;
  private float mRotationCount;
  private double mWidth;
  private double mHeight;
  boolean mFinishing;

  public MaterialProgressDrawable(Context context, View parent) {
    mParent = parent;
    mResources = context.getResources();

    mRing = new Ring(mCallback);
    mRing.setColors(COLORS);

    updateSizes(DEFAULT);
    setupAnimators();
  }

  private void setSizeParameters(double progressCircleWidth, double progressCircleHeight,
                                 double centerRadius, double strokeWidth, float arrowWidth, float arrowHeight) {
    final Ring ring = mRing;
    final DisplayMetrics metrics = mResources.getDisplayMetrics();
    final float screenDensity = metrics.density;

    mWidth = progressCircleWidth * screenDensity;
    mHeight = progressCircleHeight * screenDensity;
    ring.setStrokeWidth((float) strokeWidth * screenDensity);
    ring.setCenterRadius(centerRadius * screenDensity);
    ring.setColorIndex(0);
    ring.setArrowDimensions(arrowWidth * screenDensity, arrowHeight * screenDensity);
    ring.setInsets((int) mWidth, (int) mHeight);
  }

  /**
   * Set the overall size for the progress spinner. This updates the radius
   * and stroke width of the ring.
   *
   * @param size One of {@link MaterialProgressDrawable.LARGE} or
   *            {@link MaterialProgressDrawable.DEFAULT}
   */
  public void updateSizes(@ProgressDrawableSize int size) {
    if (size == LARGE) {
      setSizeParameters(CIRCLE_DIAMETER_LARGE, CIRCLE_DIAMETER_LARGE, CENTER_RADIUS_LARGE,
                        STROKE_WIDTH_LARGE, ARROW_WIDTH_LARGE, ARROW_HEIGHT_LARGE);
    } else {
      setSizeParameters(CIRCLE_DIAMETER, CIRCLE_DIAMETER, CENTER_RADIUS, STROKE_WIDTH,
                        ARROW_WIDTH, ARROW_HEIGHT);
    }
  }

  /**
   * @param show Set to true to display the arrowhead on the progress spinner.
   */
  public void showArrow(boolean show) {
    mRing.setShowArrow(show);
  }

  /**
   * @param scale Set the scale of the arrowhead for the spinner.
   */
  public void setArrowScale(float scale) {
    mRing.setArrowScale(scale);
  }

  /**
   * Set the start and end trim for the progress spinner arc.
   *
   * @param startAngle start angle
   * @param endAngle end angle
   */
  public void setStartEndTrim(float startAngle, float endAngle) {
    mRing.setStartTrim(startAngle);
    mRing.setEndTrim(endAngle);
  }

  /**
   * Set the amount of rotation to apply to the progress spinner.
   *
   * @param rotation Rotation is from [0..1]
   */
  public void setProgressRotation(float rotation) {
    mRing.setRotation(rotation);
  }

  /**
   * Update the background color of the circle image view.
   */
  public void setBackgroundColor(int color) {
    mRing.setBackgroundColor(color);
  }

  /**
   * Set the colors used in the progress animation from color resources.
   * The first color will also be the color of the bar that grows in response
   * to a user swipe gesture.
   *
   * @param colors
   */
  public void setColorSchemeColors(int... colors) {
    mRing.setColors(colors);
    mRing.setColorIndex(0);
  }

  @Override
  public int getIntrinsicHeight() {
    return (int) mHeight;
  }

  @Override
  public int getIntrinsicWidth() {
    return (int) mWidth;
  }

  @Override
  public void draw(Canvas c) {
    final Rect bounds = getBounds();
    final int saveCount = c.save();
    c.rotate(mRotation, bounds.exactCenterX(), bounds.exactCenterY());
    mRing.draw(c, bounds);
    c.restoreToCount(saveCount);
  }

  @Override
  public void setAlpha(int alpha) {
    mRing.setAlpha(alpha);
  }

  public int getAlpha() {
    return mRing.getAlpha();
  }

  @Override
  public void setColorFilter(ColorFilter colorFilter) {
    mRing.setColorFilter(colorFilter);
  }

  @SuppressWarnings("unused")
  void setRotation(float rotation) {
    mRotation = rotation;
    invalidateSelf();
  }

  @SuppressWarnings("unused")
  private float getRotation() {
    return mRotation;
  }

  @Override
  public int getOpacity() {
    return PixelFormat.TRANSLUCENT;
  }

  @Override
  public boolean isRunning() {
    final ArrayList<Animation> animators = mAnimators;
    final int N = animators.size();
    for (int i = 0; i < N; i++) {
      final Animation animator = animators.get(i);
      if (animator.hasStarted() && !animator.hasEnded()) {
        return true;
      }
    }
    return false;
  }

  @Override
  public void start() {
    mAnimation.reset();
    mRing.storeOriginals();
    // Already showing some part of the ring
    if (mRing.getEndTrim() != mRing.getStartTrim()) {
      mFinishing = true;
      mAnimation.setDuration(ANIMATION_DURATION / 2);
      mParent.startAnimation(mAnimation);
    } else {
      mRing.setColorIndex(0);
      mRing.resetOriginals();
      mAnimation.setDuration(ANIMATION_DURATION);
      mParent.startAnimation(mAnimation);
    }
  }

  @Override
  public void stop() {
    mParent.clearAnimation();
    setRotation(0);
    mRing.setShowArrow(false);
    mRing.setColorIndex(0);
    mRing.resetOriginals();
  }

  private float getMinProgressArc(Ring ring) {
    return (float) Math.toRadians(
        ring.getStrokeWidth() / (2 * Math.PI * ring.getCenterRadius()));
  }

  // Adapted from ArgbEvaluator.java
  private int evaluateColorChange(float fraction, int startValue, int endValue) {
    int startInt = (Integer) startValue;
    int startA = (startInt >> 24) & 0xff;
    int startR = (startInt >> 16) & 0xff;
    int startG = (startInt >> 8) & 0xff;
    int startB = startInt & 0xff;

    int endInt = (Integer) endValue;
    int endA = (endInt >> 24) & 0xff;
    int endR = (endInt >> 16) & 0xff;
    int endG = (endInt >> 8) & 0xff;
    int endB = endInt & 0xff;

    return (int) ((startA + (int) (fraction * (endA - startA))) << 24) |
           (int) ((startR + (int) (fraction * (endR - startR))) << 16) |
           (int) ((startG + (int) (fraction * (endG - startG))) << 8) |
           (int) ((startB + (int) (fraction * (endB - startB))));
  }

  /**
   * Update the ring color if this is within the last 25% of the animation.
   * The new ring color will be a translation from the starting ring color to
   * the next color.
   */
  private void updateRingColor(float interpolatedTime, Ring ring) {
    if (interpolatedTime > COLOR_START_DELAY_OFFSET) {
      // scale the interpolatedTime so that the full
      // transformation from 0 - 1 takes place in the
      // remaining time
      ring.setColor(evaluateColorChange((interpolatedTime - COLOR_START_DELAY_OFFSET)
                                        / (1.0f - COLOR_START_DELAY_OFFSET), ring.getStartingColor(),
                                        ring.getNextColor()));
    }
  }

  private void applyFinishTranslation(float interpolatedTime, Ring ring) {
    // shrink back down and complete a full rotation before
    // starting other circles
    // Rotation goes between [0..1].
    updateRingColor(interpolatedTime, ring);
    float targetRotation = (float) (Math.floor(ring.getStartingRotation() / MAX_PROGRESS_ARC)
                                    + 1f);
    final float minProgressArc = getMinProgressArc(ring);
    final float startTrim = ring.getStartingStartTrim()
                            + (ring.getStartingEndTrim() - minProgressArc - ring.getStartingStartTrim())
                              * interpolatedTime;
    ring.setStartTrim(startTrim);
    ring.setEndTrim(ring.getStartingEndTrim());
    final float rotation = ring.getStartingRotation()
                           + ((targetRotation - ring.getStartingRotation()) * interpolatedTime);
    ring.setRotation(rotation);
  }

  private void setupAnimators() {
    final Ring ring = mRing;
    final Animation animation = new Animation() {
      @Override
      public void applyTransformation(float interpolatedTime, Transformation t) {
        if (mFinishing) {
          applyFinishTranslation(interpolatedTime, ring);
        } else {
          // The minProgressArc is calculated from 0 to create an
          // angle that matches the stroke width.
          final float minProgressArc = getMinProgressArc(ring);
          final float startingEndTrim = ring.getStartingEndTrim();
          final float startingTrim = ring.getStartingStartTrim();
          final float startingRotation = ring.getStartingRotation();

          updateRingColor(interpolatedTime, ring);

          // Moving the start trim only occurs in the first 50% of a
          // single ring animation
          if (interpolatedTime <= START_TRIM_DURATION_OFFSET) {
            // scale the interpolatedTime so that the full
            // transformation from 0 - 1 takes place in the
            // remaining time
            final float scaledTime = (interpolatedTime)
                                     / (1.0f - START_TRIM_DURATION_OFFSET);
            final float startTrim = startingTrim
                                    + ((MAX_PROGRESS_ARC - minProgressArc) * MATERIAL_INTERPOLATOR
                .getInterpolation(scaledTime));
            ring.setStartTrim(startTrim);
          }

          // Moving the end trim starts after 50% of a single ring
          // animation completes
          if (interpolatedTime > END_TRIM_START_DELAY_OFFSET) {
            // scale the interpolatedTime so that the full
            // transformation from 0 - 1 takes place in the
            // remaining time
            final float minArc = MAX_PROGRESS_ARC - minProgressArc;
            float scaledTime = (interpolatedTime - START_TRIM_DURATION_OFFSET)
                               / (1.0f - START_TRIM_DURATION_OFFSET);
            final float endTrim = startingEndTrim
                                  + (minArc * MATERIAL_INTERPOLATOR.getInterpolation(scaledTime));
            ring.setEndTrim(endTrim);
          }

          final float rotation = startingRotation + (0.25f * interpolatedTime);
          ring.setRotation(rotation);

          float groupRotation = ((FULL_ROTATION / NUM_POINTS) * interpolatedTime)
                                + (FULL_ROTATION * (mRotationCount / NUM_POINTS));
          setRotation(groupRotation);
        }
      }
    };
    animation.setRepeatCount(Animation.INFINITE);
    animation.setRepeatMode(Animation.RESTART);
    animation.setInterpolator(LINEAR_INTERPOLATOR);
    animation.setAnimationListener(new Animation.AnimationListener() {

      @Override
      public void onAnimationStart(Animation animation) {
        mRotationCount = 0;
      }

      @Override
      public void onAnimationEnd(Animation animation) {
        // do nothing
      }

      @Override
      public void onAnimationRepeat(Animation animation) {
        ring.storeOriginals();
        ring.goToNextColor();
        ring.setStartTrim(ring.getEndTrim());
        if (mFinishing) {
          // finished closing the last ring from the swipe gesture; go
          // into progress mode
          mFinishing = false;
          animation.setDuration(ANIMATION_DURATION);
          ring.setShowArrow(false);
        } else {
          mRotationCount = (mRotationCount + 1) % (NUM_POINTS);
        }
      }
    });
    mAnimation = animation;
  }

  private final Callback mCallback = new Callback() {
    @Override
    public void invalidateDrawable(Drawable d) {
      invalidateSelf();
    }

    @Override
    public void scheduleDrawable(Drawable d, Runnable what, long when) {
      scheduleSelf(what, when);
    }

    @Override
    public void unscheduleDrawable(Drawable d, Runnable what) {
      unscheduleSelf(what);
    }
  };

  private static class Ring {

    private final RectF mTempBounds = new RectF();
    private final Paint mPaint = new Paint();
    private final Paint mArrowPaint = new Paint();

    private final Callback mCallback;

    private float mStartTrim = 0.0f;
    private float mEndTrim = 0.0f;
    private float mRotation = 0.0f;
    private float mStrokeWidth = 5.0f;
    private float mStrokeInset = 2.5f;

    private int[] mColors;
    // mColorIndex represents the offset into the available mColors that the
    // progress circle should currently display. As the progress circle is
    // animating, the mColorIndex moves by one to the next available color.
    private int mColorIndex;
    private float mStartingStartTrim;
    private float mStartingEndTrim;
    private float mStartingRotation;
    private boolean mShowArrow;
    private Path mArrow;
    private float mArrowScale;
    private double mRingCenterRadius;
    private int mArrowWidth;
    private int mArrowHeight;
    private int mAlpha;
    private final Paint mCirclePaint = new Paint(Paint.ANTI_ALIAS_FLAG);
    private int mBackgroundColor;
    private int mCurrentColor;

    public Ring(Callback callback) {
      mCallback = callback;

      mPaint.setStrokeCap(Paint.Cap.SQUARE);
      mPaint.setAntiAlias(true);
      mPaint.setStyle(Style.STROKE);

      mArrowPaint.setStyle(Style.FILL);
      mArrowPaint.setAntiAlias(true);
    }

    public void setBackgroundColor(int color) {
      mBackgroundColor = color;
    }

    /**
     * Set the dimensions of the arrowhead.
     *
     * @param width Width of the hypotenuse of the arrow head
     * @param height Height of the arrow point
     */
    public void setArrowDimensions(float width, float height) {
      mArrowWidth = (int) width;
      mArrowHeight = (int) height;
    }

    /**
     * Draw the progress spinner
     */
    public void draw(Canvas c, Rect bounds) {
      final RectF arcBounds = mTempBounds;
      arcBounds.set(bounds);
      arcBounds.inset(mStrokeInset, mStrokeInset);

      final float startAngle = (mStartTrim + mRotation) * 360;
      final float endAngle = (mEndTrim + mRotation) * 360;
      float sweepAngle = endAngle - startAngle;

      mPaint.setColor(mCurrentColor);
      c.drawArc(arcBounds, startAngle, sweepAngle, false, mPaint);

      drawTriangle(c, startAngle, sweepAngle, bounds);

      if (mAlpha < 255) {
        mCirclePaint.setColor(mBackgroundColor);
        mCirclePaint.setAlpha(255 - mAlpha);
        c.drawCircle(bounds.exactCenterX(), bounds.exactCenterY(), bounds.width() / 2,
                     mCirclePaint);
      }
    }

    private void drawTriangle(Canvas c, float startAngle, float sweepAngle, Rect bounds) {
      if (mShowArrow) {
        if (mArrow == null) {
          mArrow = new Path();
          mArrow.setFillType(Path.FillType.EVEN_ODD);
        } else {
          mArrow.reset();
        }

        // Adjust the position of the triangle so that it is inset as
        // much as the arc, but also centered on the arc.
        float inset = (int) mStrokeInset / 2 * mArrowScale;
        float x = (float) (mRingCenterRadius * Math.cos(0) + bounds.exactCenterX());
        float y = (float) (mRingCenterRadius * Math.sin(0) + bounds.exactCenterY());

        // Update the path each time. This works around an issue in SKIA
        // where concatenating a rotation matrix to a scale matrix
        // ignored a starting negative rotation. This appears to have
        // been fixed as of API 21.
        mArrow.moveTo(0, 0);
        mArrow.lineTo(mArrowWidth * mArrowScale, 0);
        mArrow.lineTo((mArrowWidth * mArrowScale / 2), (mArrowHeight
                                                        * mArrowScale));
        mArrow.offset(x - inset, y);
        mArrow.close();
        // draw a triangle
        mArrowPaint.setColor(mCurrentColor);
        c.rotate(startAngle + sweepAngle - ARROW_OFFSET_ANGLE, bounds.exactCenterX(),
                 bounds.exactCenterY());
        c.drawPath(mArrow, mArrowPaint);
      }
    }

    /**
     * Set the colors the progress spinner alternates between.
     *
     * @param colors Array of integers describing the colors. Must be non-<code>null</code>.
     */
    public void setColors(@NonNull int[] colors) {
      mColors = colors;
      // if colors are reset, make sure to reset the color index as well
      setColorIndex(0);
    }

    /**
     * Set the absolute color of the progress spinner. This is should only
     * be used when animating between current and next color when the
     * spinner is rotating.
     *
     * @param color int describing the color.
     */
    public void setColor(int color) {
      mCurrentColor = color;
    }

    /**
     * @param index Index into the color array of the color to display in
     *            the progress spinner.
     */
    public void setColorIndex(int index) {
      mColorIndex = index;
      mCurrentColor = mColors[mColorIndex];
    }

    /**
     * @return int describing the next color the progress spinner should use when drawing.
     */
    public int getNextColor() {
      return mColors[getNextColorIndex()];
    }

    private int getNextColorIndex() {
      return (mColorIndex + 1) % (mColors.length);
    }

    /**
     * Proceed to the next available ring color. This will automatically
     * wrap back to the beginning of colors.
     */
    public void goToNextColor() {
      setColorIndex(getNextColorIndex());
    }

    public void setColorFilter(ColorFilter filter) {
      mPaint.setColorFilter(filter);
      invalidateSelf();
    }

    /**
     * @param alpha Set the alpha of the progress spinner and associated arrowhead.
     */
    public void setAlpha(int alpha) {
      mAlpha = alpha;
    }

    /**
     * @return Current alpha of the progress spinner and arrowhead.
     */
    public int getAlpha() {
      return mAlpha;
    }

    /**
     * @param strokeWidth Set the stroke width of the progress spinner in pixels.
     */
    public void setStrokeWidth(float strokeWidth) {
      mStrokeWidth = strokeWidth;
      mPaint.setStrokeWidth(strokeWidth);
      invalidateSelf();
    }

    @SuppressWarnings("unused")
    public float getStrokeWidth() {
      return mStrokeWidth;
    }

    @SuppressWarnings("unused")
    public void setStartTrim(float startTrim) {
      mStartTrim = startTrim;
      invalidateSelf();
    }

    @SuppressWarnings("unused")
    public float getStartTrim() {
      return mStartTrim;
    }

    public float getStartingStartTrim() {
      return mStartingStartTrim;
    }

    public float getStartingEndTrim() {
      return mStartingEndTrim;
    }

    public int getStartingColor() {
      return mColors[mColorIndex];
    }

    @SuppressWarnings("unused")
    public void setEndTrim(float endTrim) {
      mEndTrim = endTrim;
      invalidateSelf();
    }

    @SuppressWarnings("unused")
    public float getEndTrim() {
      return mEndTrim;
    }

    @SuppressWarnings("unused")
    public void setRotation(float rotation) {
      mRotation = rotation;
      invalidateSelf();
    }

    @SuppressWarnings("unused")
    public float getRotation() {
      return mRotation;
    }

    public void setInsets(int width, int height) {
      final float minEdge = (float) Math.min(width, height);
      float insets;
      if (mRingCenterRadius <= 0 || minEdge < 0) {
        insets = (float) Math.ceil(mStrokeWidth / 2.0f);
      } else {
        insets = (float) (minEdge / 2.0f - mRingCenterRadius);
      }
      mStrokeInset = insets;
    }

    @SuppressWarnings("unused")
    public float getInsets() {
      return mStrokeInset;
    }

    /**
     * @param centerRadius Inner radius in px of the circle the progress
     *            spinner arc traces.
     */
    public void setCenterRadius(double centerRadius) {
      mRingCenterRadius = centerRadius;
    }

    public double getCenterRadius() {
      return mRingCenterRadius;
    }

    /**
     * @param show Set to true to show the arrow head on the progress spinner.
     */
    public void setShowArrow(boolean show) {
      if (mShowArrow != show) {
        mShowArrow = show;
        invalidateSelf();
      }
    }

    /**
     * @param scale Set the scale of the arrowhead for the spinner.
     */
    public void setArrowScale(float scale) {
      if (scale != mArrowScale) {
        mArrowScale = scale;
        invalidateSelf();
      }
    }

    /**
     * @return The amount the progress spinner is currently rotated, between [0..1].
     */
    public float getStartingRotation() {
      return mStartingRotation;
    }

    /**
     * If the start / end trim are offset to begin with, store them so that
     * animation starts from that offset.
     */
    public void storeOriginals() {
      mStartingStartTrim = mStartTrim;
      mStartingEndTrim = mEndTrim;
      mStartingRotation = mRotation;
    }

    /**
     * Reset the progress spinner to default rotation, start and end angles.
     */
    public void resetOriginals() {
      mStartingStartTrim = 0;
      mStartingEndTrim = 0;
      mStartingRotation = 0;
      setStartTrim(0);
      setEndTrim(0);
      setRotation(0);
    }

    private void invalidateSelf() {
      mCallback.invalidateDrawable(null);
    }
  }
}