/*

 * Copyright 1999-2006 Sun Microsystems, Inc.  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.  Sun designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,

 * CA 95054 USA or visit www.sun.com if you need additional information or

 * have any questions.

 */

package javax.swing.text;

import java.awt.*;

/**

 * A class to perform rendering of the glyphs.

 * This can be implemented to be stateless, or

 * to hold some information as a cache to

 * facilitate faster rendering and model/view

 * translation.  At a minimum, the GlyphPainter

 * allows a View implementation to perform its

 * duties independent of a particular version

 * of JVM and selection of capabilities (i.e.

 * shaping for i18n, etc).

 * <p>

 * This implementation is intended for operation

 * under the JDK1.1 API of the Java Platform.

 * Since the JDK is backward compatible with

 * JDK1.1 API, this class will also function on

 * Java 2.  The JDK introduces improved

 * API for rendering text however, so the GlyphPainter2

 * is recommended for the DK.

 *

 * @author  Timothy Prinzing

 * @see GlyphView

 */

class GlyphPainter1 extends GlyphView.GlyphPainter {

    /**

     * Determine the span the glyphs given a start location

     * (for tab expansion).

     */

    public float getSpan(GlyphView v, int p0, int p1,

                         TabExpander e, float x) {

        sync(v);

        Segment text = v.getText(p0, p1);

        int[] justificationData = getJustificationData(v);

        int width = Utilities.getTabbedTextWidth(v, text, metrics, (int) x, e, p0,

                                                 justificationData);

        SegmentCache.releaseSharedSegment(text);

        return width;

    }

    public float getHeight(GlyphView v) {

        sync(v);

        return metrics.getHeight();

    }

    /**

     * Fetches the ascent above the baseline for the glyphs

     * corresponding to the given range in the model.

     */

    public float getAscent(GlyphView v) {

        sync(v);

        return metrics.getAscent();

    }

    /**

     * Fetches the descent below the baseline for the glyphs

     * corresponding to the given range in the model.

     */

    public float getDescent(GlyphView v) {

        sync(v);

        return metrics.getDescent();

    }

    /**

     * Paints the glyphs representing the given range.

     */

    public void paint(GlyphView v, Graphics g, Shape a, int p0, int p1) {

        sync(v);

        Segment text;

        TabExpander expander = v.getTabExpander();

        Rectangle alloc = (a instanceof Rectangle) ? (Rectangle)a : a.getBounds();

        // determine the x coordinate to render the glyphs

        int x = alloc.x;

        int p = v.getStartOffset();

        int[] justificationData = getJustificationData(v);

        if (p != p0) {

            text = v.getText(p, p0);

            int width = Utilities.getTabbedTextWidth(v, text, metrics, x, expander, p,

                                                     justificationData);

            x += width;

            SegmentCache.releaseSharedSegment(text);

        }

        // determine the y coordinate to render the glyphs

        int y = alloc.y + metrics.getHeight() - metrics.getDescent();

        // render the glyphs

        text = v.getText(p0, p1);

        g.setFont(metrics.getFont());

        Utilities.drawTabbedText(v, text, x, y, g, expander,p0,

                                 justificationData);

        SegmentCache.releaseSharedSegment(text);

    }

    public Shape modelToView(GlyphView v, int pos, Position.Bias bias,

                             Shape a) throws BadLocationException {

        sync(v);

        Rectangle alloc = (a instanceof Rectangle) ? (Rectangle)a : a.getBounds();

        int p0 = v.getStartOffset();

        int p1 = v.getEndOffset();

        TabExpander expander = v.getTabExpander();

        Segment text;

        if(pos == p1) {

            // The caller of this is left to right and borders a right to

            // left view, return our end location.

            return new Rectangle(alloc.x + alloc.width, alloc.y, 0,

                                 metrics.getHeight());

        }

        if ((pos >= p0) && (pos <= p1)) {

            // determine range to the left of the position

            text = v.getText(p0, pos);

            int[] justificationData = getJustificationData(v);

            int width = Utilities.getTabbedTextWidth(v, text, metrics, alloc.x, expander, p0,

                                                     justificationData);

            SegmentCache.releaseSharedSegment(text);

            return new Rectangle(alloc.x + width, alloc.y, 0, metrics.getHeight());

        }

        throw new BadLocationException("modelToView - can't convert", p1);

    }

    /**

     * Provides a mapping from the view coordinate space to the logical

     * coordinate space of the model.

     *

     * @param v the view containing the view coordinates

     * @param x the X coordinate

     * @param y the Y coordinate

     * @param a the allocated region to render into

     * @param biasReturn always returns <code>Position.Bias.Forward</code>

     *   as the zero-th element of this array

     * @return the location within the model that best represents the

     *  given point in the view

     * @see View#viewToModel

     */

    public int viewToModel(GlyphView v, float x, float y, Shape a,

                           Position.Bias[] biasReturn) {

        sync(v);

        Rectangle alloc = (a instanceof Rectangle) ? (Rectangle)a : a.getBounds();

        int p0 = v.getStartOffset();

        int p1 = v.getEndOffset();

        TabExpander expander = v.getTabExpander();

        Segment text = v.getText(p0, p1);

        int[] justificationData = getJustificationData(v);

        int offs = Utilities.getTabbedTextOffset(v, text, metrics,

                                                 alloc.x, (int) x, expander, p0,

                                                 justificationData);

        SegmentCache.releaseSharedSegment(text);

        int retValue = p0 + offs;

        if(retValue == p1) {

            // No need to return backward bias as GlyphPainter1 is used for

            // ltr text only.

            retValue--;

        }

        biasReturn[0] = Position.Bias.Forward;

        return retValue;

    }

    /**

     * Determines the best location (in the model) to break

     * the given view.

     * This method attempts to break on a whitespace

     * location.  If a whitespace location can't be found, the

     * nearest character location is returned.

     *

     * @param v the view

     * @param p0 the location in the model where the

     *  fragment should start its representation >= 0

     * @param pos the graphic location along the axis that the

     *  broken view would occupy >= 0; this may be useful for

     *  things like tab calculations

     * @param len specifies the distance into the view

     *  where a potential break is desired >= 0

     * @return the model location desired for a break

     * @see View#breakView

     */

    public int getBoundedPosition(GlyphView v, int p0, float x, float len) {

        sync(v);

        TabExpander expander = v.getTabExpander();

        Segment s = v.getText(p0, v.getEndOffset());

        int[] justificationData = getJustificationData(v);

        int index = Utilities.getTabbedTextOffset(v, s, metrics, (int)x, (int)(x+len),

                                                  expander, p0, false,

                                                  justificationData);

        SegmentCache.releaseSharedSegment(s);

        int p1 = p0 + index;

        return p1;

    }

    void sync(GlyphView v) {

        Font f = v.getFont();

        if ((metrics == null) || (! f.equals(metrics.getFont()))) {

            // fetch a new FontMetrics

            Container c = v.getContainer();

            metrics = (c != null) ? c.getFontMetrics(f) :

                Toolkit.getDefaultToolkit().getFontMetrics(f);

        }

    }

    /**

     * @return justificationData from the ParagraphRow this GlyphView

     * is in or {@code null} if no justification is needed

     */

    private int[] getJustificationData(GlyphView v) {

        View parent = v.getParent();

        int [] ret = null;

        if (parent instanceof ParagraphView.Row) {

            ParagraphView.Row row = ((ParagraphView.Row) parent);

            ret = row.justificationData;

        }

        return ret;

    }

    // --- variables ---------------------------------------------

    FontMetrics metrics;

}