/*
    GNU GENERAL LICENSE
    Copyright (C) 2006 The Lobo Project. Copyright (C) 2014 - 2017 Lobo Evolution

    This program is free software; you can redistribute it and/or
    modify it under the terms of the GNU General Public
    License as published by the Free Software Foundation; either
    verion 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
    General License for more details.

    You should have received a copy of the GNU General Public
    along with this program.  If not, see <http://www.gnu.org/licenses/>.
    

    Contact info: lobochief@users.sourceforge.net; ivan.difrancesco@yahoo.it
 */

package org.lobobrowser.html.renderstate;

import java.awt.Font;
import java.awt.FontMetrics;
import java.awt.Toolkit;
import java.util.HashMap;
import java.util.Map;

import org.lobobrowser.html.info.WordInfo;
import org.lobobrowser.html.style.RenderStateDelegator;
import org.lobobrowser.util.gui.FontFactory;
import org.lobobrowser.util.gui.FontKey;

/**
 * The Class FontStyleRenderState.
 */
public class FontStyleRenderState extends RenderStateDelegator {

    /** The style. */
    private final int style;

    /** The superscript. */
    private final Integer superscript;

    /**
     * Instantiates a new font style render state.
     *
     * @param prevRenderState
     *            the prev render state
     * @param style
     *            the style
     */
    public FontStyleRenderState(RenderState prevRenderState, int style) {
        this(prevRenderState, style, null);
    }

    /**
     * Instantiates a new font style render state.
     *
     * @param prevRenderState
     *            the prev render state
     * @param style
     *            the style
     * @param superscript
     *            the superscript
     */
    FontStyleRenderState(RenderState prevRenderState, int style,
            Integer superscript) {
        super(prevRenderState);
        this.style = style;
        this.superscript = superscript;
    }

    /**
     * Creates the superscript font style render state.
     *
     * @param prevRenderState
     *            the prev render state
     * @param superscript
     *            the superscript
     * @return the font style render state
     */
    public static FontStyleRenderState createSuperscriptFontStyleRenderState(
            RenderState prevRenderState, Integer superscript) {
        return new FontStyleRenderState(prevRenderState, prevRenderState
                .getFont().getStyle(), superscript);
    }

    /** The i font. */
    private Font iFont;

    /*
     * (non-Javadoc)
     * @see org.lobobrowser.html.style.RenderStateDelegator#getFont()
     */
    @Override
    public Font getFont() {
        Font f = this.iFont;
        if (f != null) {
            return f;
        }
        Font parentFont = this.delegate.getFont();
        if (parentFont.getStyle() != this.style) {
            f = parentFont.deriveFont(this.style | parentFont.getStyle());
        } else {
            f = parentFont;
        }
        
        f = FontFactory.scriptFont(f, new FontKey("", "", "", "", 0, null, superscript, 0, false, 0));

        this.iFont = f;
        return f;
    }

    /** The i font metrics. */
    private FontMetrics iFontMetrics;

    /*
     * (non-Javadoc)
     * @see org.lobobrowser.html.style.RenderStateDelegator#getFontMetrics()
     */
    @Override
    public FontMetrics getFontMetrics() {
        FontMetrics fm = this.iFontMetrics;
        if (fm == null) {
            // TODO getFontMetrics deprecated. How to get text width?
            fm = Toolkit.getDefaultToolkit().getFontMetrics(this.getFont());
            this.iFontMetrics = fm;
        }
        return fm;
    }

    /*
     * (non-Javadoc)
     * @see org.lobobrowser.html.style.RenderStateDelegator#invalidate()
     */
    @Override
    public void invalidate() {
        this.delegate.invalidate();
        this.iFont = null;
        this.iFontMetrics = null;
        Map<String, WordInfo> map = this.iWordInfoMap;
        if (map != null) {
            map.clear();
        }
    }

    /** The i word info map. */
    Map<String, WordInfo> iWordInfoMap = null;

    /*
     * (non-Javadoc)
     * @see
     * org.lobobrowser.html.style.RenderStateDelegator#getWordInfo(java.lang.String)
     */
    @Override
    public final WordInfo getWordInfo(String word) {
        // Expected to be called only in the GUI (rendering) thread.
        // No synchronization necessary.
        Map<String, WordInfo> map = this.iWordInfoMap;
        if (map == null) {
            map = new HashMap<String, WordInfo>(1);
            this.iWordInfoMap = map;
        }
        WordInfo wi = map.get(word);
        if (wi != null) {
            return wi;
        }
        wi = new WordInfo();
        FontMetrics fm = this.getFontMetrics();
        wi.setFontMetrics(fm);
        wi.setAscentPlusLeading(fm.getAscent() + fm.getLeading());
        wi.setDescent(fm.getDescent());
        wi.setHeight(fm.getHeight());
        wi.setWidth(fm.stringWidth(word));
        map.put(word, wi);
        return wi;
    }
}