/*
 * Copyright 2017 nebular
 * Copyright 2017 devemux86
 * Copyright 2017 Wolfgang Schramm
 *
 * This program is free software: you can redistribute it and/or modify it under the
 * terms of the GNU Lesser General Public License as published by the Free Software
 * Foundation, either version 3 of the License, or (at your option) any later version.
 *
 * This program 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 Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License along with
 * this program. If not, see <http://www.gnu.org/licenses/>.
 */
package org.oscim.android.cluster;

import org.oscim.backend.CanvasAdapter;
import org.oscim.backend.canvas.Bitmap;
import org.oscim.backend.canvas.Canvas;
import org.oscim.backend.canvas.Paint;

/**
 * A simple utility class to make clustered markers functionality self-contained.
 * Includes a method to translate between DPs and PXs and a circular icon generator.
 */
public class ClusterUtils {

    /**
     * Get pixels from DPs
     *
     * @param dp Value in DPs
     * @return Value in PX according to screen density
     */
    public static int getPixels(float dp) {
        return (int) (CanvasAdapter.getScale() * dp);
    }

    public static class ClusterDrawable {
        private final Paint mPaintText = CanvasAdapter.newPaint();
        private final Paint mPaintCircle = CanvasAdapter.newPaint();
        private final Paint mPaintBorder = CanvasAdapter.newPaint();
        private int mSize;
        private String mText;

        /**
         * Generates a circle with a number inside
         *
         * @param sizedp          Size in DPs
         * @param foregroundColor Foreground
         * @param backgroundColor Background
         * @param text            Text inside. Will only work for a single character!
         */
        public ClusterDrawable(int sizedp, int foregroundColor, int backgroundColor, String text) {
            setup(sizedp, foregroundColor, backgroundColor);
            setText(text);
        }

        private void setup(int sizedp, int foregroundColor, int backgroundColor) {
            mSize = ClusterUtils.getPixels(sizedp);
            mPaintText.setTextSize(ClusterUtils.getPixels((int) (sizedp * 0.6666666)));
            mPaintText.setColor(foregroundColor);

            mPaintCircle.setColor(backgroundColor);
            mPaintCircle.setStyle(Paint.Style.FILL);

            mPaintBorder.setColor(foregroundColor);
            mPaintBorder.setStyle(Paint.Style.STROKE);
            mPaintBorder.setStrokeWidth(2.0f * CanvasAdapter.getScale());
        }

        private void setText(String text) {
            mText = text;
        }

        private void draw(Canvas canvas) {
            int halfsize = mSize >> 1;
            final int noneClippingRadius = halfsize - getPixels(2);

            // fill
            canvas.drawCircle(halfsize, halfsize, noneClippingRadius, mPaintCircle);
            // outline
            canvas.drawCircle(halfsize, halfsize, noneClippingRadius, mPaintBorder);
            // draw the number at the center
            canvas.drawText(mText,
                    (canvas.getWidth() - mPaintText.getTextWidth(mText)) * 0.5f,
                    (canvas.getHeight() + mPaintText.getTextHeight(mText)) * 0.5f,
                    mPaintText);
        }

        public Bitmap getBitmap() {
            int width = mSize, height = mSize;
            width = width > 0 ? width : 1;
            height = height > 0 ? height : 1;

            Bitmap bitmap = CanvasAdapter.newBitmap(width, height, 0);
            Canvas canvas = CanvasAdapter.newCanvas();
            canvas.setBitmap(bitmap);
            draw(canvas);

            return bitmap;
        }
    }
}