/**
 * Copyright (C) 2016 eBusiness Information
 *
 * This file is part of OSM Contributor.
 *
 * OSM Contributor is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * OSM Contributor is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with OSM Contributor.  If not, see <http://www.gnu.org/licenses/>.
 */
package io.jawg.osmcontributor.ui.utils.views;

import android.view.View;
import android.view.animation.Animation;
import android.view.animation.Transformation;
import android.widget.RelativeLayout;

public class ViewAnimation {

    // speed set to 1dp/ms
    private static final int SPEED_COEF = 1;

    public static void animate(final View v, final boolean expand) {
        if (expand) {
            expand(v);
        } else {
            collapse(v);
        }
    }

    private static void expand(final View v) {
        if (v.getVisibility() != View.VISIBLE) {

            v.measure(RelativeLayout.LayoutParams.MATCH_PARENT, RelativeLayout.LayoutParams.WRAP_CONTENT);
            final int targetHeight = v.getMeasuredHeight();

            v.getLayoutParams().height = 0;
            v.setVisibility(View.VISIBLE);
            Animation a = new Animation() {
                @Override
                protected void applyTransformation(float interpolatedTime, Transformation t) {
                    v.getLayoutParams().height = interpolatedTime == 1
                            ? RelativeLayout.LayoutParams.WRAP_CONTENT
                            : (int) (targetHeight * interpolatedTime);
                    v.requestLayout();
                }

                @Override
                public boolean willChangeBounds() {
                    return true;
                }
            };

            a.setDuration((int) (SPEED_COEF * targetHeight / v.getContext().getResources().getDisplayMetrics().density));
            v.startAnimation(a);
        }
    }

    private static void collapse(final View v) {
        if (v.getVisibility() == View.VISIBLE) {
            final int initialHeight = v.getMeasuredHeight();

            Animation a = new Animation() {
                @Override
                protected void applyTransformation(float interpolatedTime, Transformation t) {
                    if (interpolatedTime == 1) {
                        v.setVisibility(View.GONE);
                    } else {
                        v.getLayoutParams().height = initialHeight - (int) (initialHeight * interpolatedTime);
                        v.requestLayout();
                    }
                }

                @Override
                public boolean willChangeBounds() {
                    return true;
                }
            };

            a.setDuration((int) (SPEED_COEF * initialHeight / v.getContext().getResources().getDisplayMetrics().density));
            v.startAnimation(a);
        }
    }
}