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 * Copyright (c) 2011, 2012, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code 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
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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 */

package javafx.scene.layout;

import javafx.geometry.Insets;
import javafx.scene.paint.Color;
import javafx.scene.paint.Paint;
import javafx.scene.shape.StrokeType;

/**
 * Defines the stroke to use on a Border for styling a Region. The
 * stroke is a vector-based rendering that outlines the border area.
 * It can be inset (or outset) from the Region's edge, and the values
 * of the stroke are taken into account when computing the Region's
 * insets (for defining the content area). The stroke visuals are
 * not used when any BorderImages are in use.
 */
public class BorderStroke {
    /**
     * The default insets when "thin" is specified.
     */
    public static final BorderWidths THIN = new BorderWidths(1);

    /**
     * The default insets when "medium" is specified
     */
    public static final BorderWidths MEDIUM = new BorderWidths(3);

    /**
     * The default insets when "thick" is specified
     */
    public static final BorderWidths THICK = new BorderWidths(3);

    /**
     * The default Insets to be used with a BorderStroke that does not
     * otherwise define any.
     */
    public static final BorderWidths DEFAULT_WIDTHS = THIN;

    /**
     * Defines the fill of top side of this border.
     *
     * @defaultValue black
     */
    final Paint topStroke;
    public final Paint getTopStroke() { return topStroke; }
    // TODO: The spec says the default color is "currentColor", which appears to mean
    // by default the color is "inherit". So we should file a JIRA on this so that
    // we use inherit. But first I'd like a performance analysis.

    /**
     * Defines the fill of right side of this border. If {@code null} then the
     * topFill is used.
     *
     * @defaultValue null = same as topFill
     */
    final Paint rightStroke;
    public final Paint getRightStroke() { return rightStroke; }

    /**
     * Defines the fill of bottom side of this border. If {@code null} then the
     * topFill is used.
     *
     * @defaultValue null = same as topFill
     */
    final Paint bottomStroke;
    public final Paint getBottomStroke() { return bottomStroke; }

    /**
     * Defines the fill of left side of this border. If {@code null} then the
     * rightFill is used.
     *
     * @defaultValue null = same sa rightFill
     */
    final Paint leftStroke;
    public final Paint getLeftStroke() { return leftStroke; }

    /**
     * Defines the style of top side of this border.
     *
     * @defaultValue none
     */
    final BorderStrokeStyle topStyle;
    public final BorderStrokeStyle getTopStyle() { return topStyle; }

    /**
     * Defines the style of right side of this border. If {@code null} then
     * topStyle is used;
     *
     * @defaultValue null = same as topStyle
     */
    final BorderStrokeStyle rightStyle;
    public final BorderStrokeStyle getRightStyle() { return rightStyle; }

    /**
     * Defines the style of bottom side of this border. If {@code null} then
     * topStyle is used;  Use BorderStyle.NONE to set the border to
     * have no border style.
     *
     * @defaultValue null = same as topStyle
     */
    final BorderStrokeStyle bottomStyle;
    public final BorderStrokeStyle getBottomStyle() { return bottomStyle; }

    /**
     * Defines the style of left side of this border. If {@code null} then
     * rightStyle is used. Use BorderStyle.NONE to set the border to
     * have no border style.
     *
     * @defaultValue null = same as rightStyle
     */
    final BorderStrokeStyle leftStyle;
    public final BorderStrokeStyle getLeftStyle() { return leftStyle; }

    /**
     * Defines the thickness of each side of the BorderStroke. This will never
     * be null, and defaults to DEFAULT_WIDTHS.
     */
    final BorderWidths widths;
    public final BorderWidths getWidths() { return widths; }

    /**
     * Defines the insets of each side of the BorderStroke. This will never
     * be null, and defaults to EMPTY.
     */
    final Insets insets;
    public final Insets getInsets() { return insets; }

    // These two are used by Border to compute the insets and outsets of the border
    final Insets innerEdge;
    final Insets outerEdge;

    /**
     * Defines the radii for each corner of this BorderStroke. This will never
     * be null, and defaults to BorderRadii.EMPTY.
     */
    private final BorderRadii radii;
    public final BorderRadii getRadii() { return radii; }

    /**
     * A cached hash code
     */
    private int hash = 0;

    /**
     * Creates a new BorderStroke.
     *
     * @param stroke    The stroke to use for all sides. If null, we default to Color.BLACK.
     * @param style     The style to use for all sides. If null, we default to BorderStrokeStyle.NONE
     * @param radii     The radii to use. If null, we default to BorderRadii.EMPTY
     * @param widths    The widths to use. If null, we default to DEFAULT_WIDTHS
     */
    public BorderStroke(Paint stroke, BorderStrokeStyle style, BorderRadii radii, BorderWidths widths) {
        this.leftStroke = this.topStroke = this.rightStroke = this.bottomStroke = stroke == null ? Color.BLACK : stroke;
        this.topStyle = this.rightStyle = this.bottomStyle = this.leftStyle = style == null ? BorderStrokeStyle.NONE : style;
        this.radii = radii == null ? BorderRadii.EMPTY : radii;
        this.widths = widths == null ? DEFAULT_WIDTHS : widths;
        this.insets = Insets.EMPTY;

        StrokeType type = this.topStyle.getType();
        double inside, outside;
        if (type == StrokeType.OUTSIDE) {
            outside = this.widths.getTop();
            inside = 0;
        } else if (type == StrokeType.CENTERED) {
            outside = inside = this.getWidths().getTop() / 2.0;
        } else if (type == StrokeType.INSIDE) {
            outside = 0;
            inside = this.widths.getTop();
        } else {
            throw new AssertionError("Unexpected Stroke Type");
        }
        innerEdge = new Insets(inside);
        outerEdge = new Insets(outside);
    }

    /**
     * Create a new BorderStroke, specifying all construction parameters.
     *
     * @param topStroke       The fill to use on the top. If null, defaults to BLACK.
     * @param rightStroke     The fill to use on the right. If null, defaults to the same value as topStroke
     * @param bottomStroke    The fill to use on the bottom. If null, defaults to the same value as bottomStroke
     * @param leftStroke      The fill to use on the left. If null, defaults to the same value as rightStroke
     * @param topStyle        The style to use on the top. If null, defaults to BorderStrokeStyle.NONE
     * @param rightStyle      The style to use on the right. If null, defaults to the same value as topStyle
     * @param bottomStyle     The style to use on the bottom. If null, defaults to the same value as topStyle
     * @param leftStyle       The style to use on the left. If null, defaults to the same value as rightStyle
     * @param radii           The radii. If null, we default to square corners by using BorderRadii.EMPTY
     * @param widths          The thickness of each side. If null, we default to DEFAULT_WIDTHS.
     * @param insets    The insets indicating where to draw the border relative to the region edges.
     */
    public BorderStroke(
            Paint topStroke, Paint rightStroke, Paint bottomStroke, Paint leftStroke,
            BorderStrokeStyle topStyle, BorderStrokeStyle rightStyle,
            BorderStrokeStyle bottomStyle, BorderStrokeStyle leftStyle,
            BorderRadii radii, BorderWidths widths, Insets insets)
    {
        this.topStroke = topStroke == null ? Color.BLACK : topStroke;
        this.rightStroke = rightStroke == null ? this.topStroke : rightStroke;
        this.bottomStroke = bottomStroke == null ? this.topStroke : bottomStroke;
        this.leftStroke = leftStroke == null ? this.rightStroke : leftStroke;
        this.topStyle = topStyle == null ? BorderStrokeStyle.NONE : topStyle;
        this.rightStyle = rightStyle == null ? this.topStyle : rightStyle;
        this.bottomStyle = bottomStyle == null ? this.topStyle : bottomStyle;
        this.leftStyle = leftStyle == null ? this.rightStyle : leftStyle;
        this.radii = radii == null ? BorderRadii.EMPTY : radii;
        this.widths = widths == null ? DEFAULT_WIDTHS : widths;
        this.insets = insets == null ? Insets.EMPTY : insets;

        innerEdge = new Insets(
                computeInside(this.topStyle.getType(), this.widths.getTop()),
                computeInside(this.rightStyle.getType(), this.widths.getRight()),
                computeInside(this.bottomStyle.getType(), this.widths.getBottom()),
                computeInside(this.leftStyle.getType(), this.widths.getLeft())
        );
        outerEdge = new Insets(
                computeOutside(this.topStyle.getType(), this.widths.getTop()),
                computeOutside(this.rightStyle.getType(), this.widths.getRight()),
                computeOutside(this.bottomStyle.getType(), this.widths.getBottom()),
                computeOutside(this.leftStyle.getType(), this.widths.getLeft())
        );
    }

    private double computeInside(StrokeType type, double width) {
        if (type == StrokeType.OUTSIDE) {
            return 0;
        } else if (type == StrokeType.CENTERED) {
            return this.getWidths().getTop() / 2.0;
        } else if (type == StrokeType.INSIDE) {
            return this.widths.getTop();
        } else {
            throw new AssertionError("Unexpected Stroke Type");
        }
    }

    private double computeOutside(StrokeType type, double width) {
        double inside, outside;
        if (type == StrokeType.OUTSIDE) {
            return this.widths.getTop();
        } else if (type == StrokeType.CENTERED) {
            return this.getWidths().getTop() / 2.0;
        } else if (type == StrokeType.INSIDE) {
            return 0;
        } else {
            throw new AssertionError("Unexpected Stroke Type");
        }
    }

    /**
     * @inheritDoc
     */
    @Override
    public boolean equals(Object o) {
        if (this == o) return true;
        if (o == null || getClass() != o.getClass()) return false;
        if (hashCode() != o.hashCode()) return false;
        BorderStroke that = (BorderStroke) o;
        if (!bottomStroke.equals(that.bottomStroke)) return false;
        if (!bottomStyle.equals(that.bottomStyle)) return false;
        if (!leftStroke.equals(that.leftStroke)) return false;
        if (!leftStyle.equals(that.leftStyle)) return false;
        if (!radii.equals(that.radii)) return false;
        if (!rightStroke.equals(that.rightStroke)) return false;
        if (!rightStyle.equals(that.rightStyle)) return false;
        if (!topStroke.equals(that.topStroke)) return false;
        if (!topStyle.equals(that.topStyle)) return false;
        if (!widths.equals(that.widths)) return false;
        if (!insets.equals(that.insets)) return false;

        return true;
    }

    /**
     * @inheritDoc
     */
    @Override
    public int hashCode() {
        if (hash == 0) {
            // Please note: I have to compute into a temporary result variable
            // before making the final assignment, or the hash code could
            // come out wrong in a multi-threaded scenario.
            int result;
            result = topStroke.hashCode();
            result = 31 * result + rightStroke.hashCode();
            result = 31 * result + bottomStroke.hashCode();
            result = 31 * result + leftStroke.hashCode();
            result = 31 * result + topStyle.hashCode();
            result = 31 * result + rightStyle.hashCode();
            result = 31 * result + bottomStyle.hashCode();
            result = 31 * result + leftStyle.hashCode();
            result = 31 * result + widths.hashCode();
            result = 31 * result + radii.hashCode();
            result = 31 * result + insets.hashCode();
            hash = result;
        }
        return hash;
    }
}