/*
 * Copyright 2010, 2011, 2012 mapsforge.org
 *
 * 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.mapsforge.android.maps.overlay;

import org.mapsforge.core.model.GeoPoint;

import android.graphics.Paint;
import android.graphics.Point;

/**
 * OverlayCircle holds all parameters of a single circle on a {@link CircleOverlay}. All rendering parameters like
 * color, stroke width, pattern and transparency can be configured via two {@link Paint} objects. Each circle is drawn
 * twice - once with each paint object - to allow for different outlines and fillings. The drawing quality can be
 * improved by enabling {@link Paint#setAntiAlias(boolean) anti-aliasing}.
 */
public class OverlayCircle {
	/**
	 * Geographical coordinate of the circle.
	 */
	protected GeoPoint center;

	/**
	 * Paint which will be used to fill the circle.
	 */
	protected Paint paintFill;

	/**
	 * Paint which will be used to draw the circle outline.
	 */
	protected Paint paintOutline;

	/**
	 * Radius of the circle in meters.
	 */
	protected float radius;

	/**
	 * Title of the circle.
	 */
	protected String title;

	/**
	 * Cached position of the circle on the map.
	 */
	Point cachedCenterPosition;

	/**
	 * Cached radius of the circle in pixels.
	 */
	float cachedRadius;

	/**
	 * Zoom level of the cached circle position.
	 */
	byte cachedZoomLevel;

	/**
	 * Flag to indicate if at least one paint is set for this circle.
	 */
	boolean hasPaint;

	/**
	 * Constructs a new OverlayCircle.
	 */
	public OverlayCircle() {
		this(null, 0, null, null, null);
	}

	/**
	 * @param center
	 *            the geographical coordinates of the center point.
	 * @param radius
	 *            the radius of the circle in meters.
	 * @param paintFill
	 *            the paint which will be used to fill the circle (may be null).
	 * @param paintOutline
	 *            the paint which will be used to draw the circle outline (may be null).
	 * @param title
	 *            the title of the circle (may be null).
	 */
	public OverlayCircle(GeoPoint center, float radius, Paint paintFill, Paint paintOutline, String title) {
		this.title = title;
		this.cachedCenterPosition = new Point();
		this.cachedZoomLevel = Byte.MIN_VALUE;
		setCircleDataInternal(center, radius);
		setPaintInternal(paintFill, paintOutline);
	}

	/**
	 * @param center
	 *            the geographical coordinates of the center point.
	 * @param radius
	 *            the radius of the circle in meters.
	 * @param title
	 *            the title of the circle (may be null).
	 */
	public OverlayCircle(GeoPoint center, float radius, String title) {
		this(center, radius, null, null, title);
	}

	/**
	 * @param paintFill
	 *            the paint which will be used to fill the circle (may be null).
	 * @param paintOutline
	 *            the paint which will be used to draw the circle outline (may be null).
	 */
	public OverlayCircle(Paint paintFill, Paint paintOutline) {
		this(null, 0, paintFill, paintOutline, null);
	}

	/**
	 * @return the title of this circle (may be null).
	 */
	public synchronized String getTitle() {
		return this.title;
	}

	/**
	 * Sets the parameters of the circle.
	 * <p>
	 * Changes might not become visible until {@link Overlay#requestRedraw()} is called.
	 * 
	 * @param center
	 *            the geographical coordinates of the center point.
	 * @param radius
	 *            the radius of the circle in meters.
	 */
	public synchronized void setCircleData(GeoPoint center, float radius) {
		setCircleDataInternal(center, radius);
	}

	/**
	 * Sets the paints which will be used to draw the overlay.
	 * <p>
	 * Changes might not become visible until {@link Overlay#requestRedraw()} is called.
	 * 
	 * @param paintFill
	 *            the paint which will be used to fill the circle (may be null).
	 * @param paintOutline
	 *            the paint which will be used to draw the circle outline (may be null).
	 */
	public synchronized void setPaint(Paint paintFill, Paint paintOutline) {
		setPaintInternal(paintFill, paintOutline);
	}

	/**
	 * Sets the title of this circle.
	 * 
	 * @param title
	 *            the title of this circle (may be null).
	 */
	public synchronized void setTitle(String title) {
		this.title = title;
	}

	private void setCircleDataInternal(GeoPoint center, float radius) {
		this.center = center;
		this.radius = radius;
		this.cachedZoomLevel = Byte.MIN_VALUE;
	}

	private void setPaintInternal(Paint paintFill, Paint paintOutline) {
		this.paintFill = paintFill;
		this.paintOutline = paintOutline;
		this.hasPaint = paintFill != null || paintOutline != null;
	}
}