/*
 * Copyright 2015-2024 MicroEJ Corp. All rights reserved.
 * This library is provided in source code for use, modification and test, subject to license terms.
 * Any modification of the source code will break MicroEJ Corp. warranties on the whole library.
 */
package ej.mwt.style.dimension;

import ej.annotation.Nullable;
import ej.bon.XMath;
import ej.mwt.Widget;
import ej.mwt.style.Style;
import ej.mwt.util.OutlineHelper;
import ej.mwt.util.Rectangle;
import ej.mwt.util.Size;

/**
 * Dimension with fixed width and/or height.
 * <p>
 * The width or height are stored as a <code>char</code> for heap optimization and therefore cannot exceed
 * <code>65535</code>.
 */
public class FixedDimension implements Dimension {

	private final char width;
	private final char height;

	/**
	 * Creates a fixed dimension with constraints.
	 * <p>
	 * {@link Widget#NO_CONSTRAINT} can be used to relax constraint on one dimension (width or height).
	 * <p>
	 * The given width and height are clamped between <code>0</code> and <code>Character.MAX_VALUE</code>.
	 *
	 * @param width
	 *            the width.
	 * @param height
	 *            the height.
	 */
	public FixedDimension(int width, int height) {
		this.width = (char) XMath.limit(width, 0, Character.MAX_VALUE);
		this.height = (char) XMath.limit(height, 0, Character.MAX_VALUE);
	}

	/**
	 * Returns the width constraint.
	 *
	 * @return the width constraint, or {@link Widget#NO_CONSTRAINT} if there is no width constraint.
	 */
	public int getWidth() {
		return this.width;
	}

	/**
	 * Returns the height constraint.
	 *
	 * @return the height constraint, or {@link Widget#NO_CONSTRAINT} if there is no height constraint.
	 */
	public int getHeight() {
		return this.height;
	}

	@Override
	public void getAvailableSize(Widget widget, int availableWidth, int availableHeight, Size availableSize) {
		if (this.width != Widget.NO_CONSTRAINT) {
			availableSize.setWidth(this.width);
		}
		if (this.height != Widget.NO_CONSTRAINT) {
			availableSize.setHeight(this.height);
		}
	}

	@Override
	public void computeOptimalSize(Widget widget, int availableWidth, int availableHeight, Size optimalSize) {
		if (this.width != Widget.NO_CONSTRAINT) {
			optimalSize.setWidth(this.width);
		}
		if (this.height != Widget.NO_CONSTRAINT) {
			optimalSize.setHeight(this.height);
		}
	}

	@Override
	public void layOut(Widget widget, Rectangle bounds) {
		Style style = widget.getStyle();

		int leftOutlines = -bounds.getX();
		int topOutlines = -bounds.getY();
		int rightOutlines = bounds.getWidth();
		int bottomOutlines = bounds.getHeight();

		OutlineHelper.applyOutlines(bounds, style);

		leftOutlines += bounds.getX();
		topOutlines += bounds.getY();
		rightOutlines -= bounds.getWidth() + leftOutlines;
		bottomOutlines -= bounds.getHeight() + topOutlines;

		DimensionHelper.layOut(widget, bounds, this.width != Widget.NO_CONSTRAINT, this.height != Widget.NO_CONSTRAINT,
				this.width, this.height);

		bounds.addOutline(leftOutlines, topOutlines, rightOutlines, bottomOutlines);
	}

	@Override
	public boolean equals(@Nullable Object obj) {
		if (obj != null && getClass() == obj.getClass()) {
			FixedDimension dimension = (FixedDimension) obj;
			return this.width == dimension.width && this.height == dimension.height;
		}
		return false;
	}

	@Override
	public int hashCode() {
		return 3 * this.width + 5 * this.height;
	}

}