/*******************************************************************************
 * Copyright (c) 2006 Sybase, Inc. and others.
 *
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *     Sybase, Inc. - initial API and implementation
 *******************************************************************************/
package org.eclipse.jst.pagedesigner.css2.font;

import org.eclipse.jst.pagedesigner.css2.ICSSStyle;
import org.eclipse.jst.pagedesigner.css2.property.FontFamilyMeta;
import org.eclipse.jst.pagedesigner.css2.property.FontSizeMeta;
import org.eclipse.jst.pagedesigner.css2.property.FontWeightMeta;
import org.eclipse.jst.pagedesigner.css2.property.ICSSPropertyID;
import org.eclipse.jst.pagedesigner.css2.value.Length;
import org.eclipse.jst.pagedesigner.utils.CacheManager;
import org.eclipse.jst.pagedesigner.utils.ICacheEntryCreator;
import org.eclipse.swt.SWT;
import org.eclipse.swt.graphics.Font;
import org.eclipse.swt.widgets.Display;

/**
 * @author mengbo
 */
public class CSSFontManager implements ICSSFontManager {
	private static CSSFontManager _instance;

	private static final boolean DEBUG = false;

	private int _totalFont = 0;

	// private static FontPoolManager _fontPoolManager;
	// Map _cache = new HashMap();

	private static final int CACHESIZE = 100; // we cache 100 font.

	// the scale to convert the px to pt.
	private final static double FONT_SCALE = ((double) Display.getCurrent()
			.getDPI().x) / 72;

	static String cssFontToLocalFont(String original) {
		if ("serif".equalsIgnoreCase(original)) {
			return "Georgia";
		} else if ("sans-serif".equalsIgnoreCase(original)) {
			return "Arial";
		} else if ("cursive".equalsIgnoreCase(original)) {
			// FIXME: MS windows does not support the alternative fonts that
			// match cursive defined at
			// http://www.w3.org/TR/REC-CSS2/fonts.html#generic-font-families,
			// We use Comic Sans MS font family
			// because it is MS alternative.
			return "Comic Sans MS";
		} else if ("fantasy".equalsIgnoreCase(original)) {
			return cssFontToLocalFont("serif");
		} else if ("monospace".equalsIgnoreCase(original)) {
			return "Courier New";
		} else {
			return original;
		}
	}

	private CacheManager _cacheManager = new CacheManager(
			new ICacheEntryCreator<CSSFont, Font>() {
				public Font createEntry(CSSFont key) {
					if (DEBUG) {
						_totalFont++;
						System.out.println("TotalFont++: " + _totalFont);
					}
					Font font = new Font(null, cssFontToLocalFont(key
							.getFontFamily()), (int) Math.round(key
							.getFontSize()
							/ FONT_SCALE), key.getSwtFontStyle());
					return font;
				}

				public void dispose(CSSFont key, Font entry) {
					if (DEBUG) {
						_totalFont--;
						System.out.println("TotalFont--: " + _totalFont);
					}
					entry.dispose();

				}
			}, CACHESIZE);

	/**
	 * constructor
	 */
	private CSSFontManager() {
		super();
	}

	private String resolveFontStyleString(ICSSStyle style) {
		StringBuffer sb = new StringBuffer();
		sb.append(ICSSPropertyID.ATTR_FONT_FAMILY).append(":");
		sb.append("'").append(
				(String) style
						.getStyleProperty(ICSSPropertyID.ATTR_FONT_FAMILY))
				.append("'");
		sb.append(";");
		sb.append(ICSSPropertyID.ATTR_FONT_STYLE).append(":");
		sb
				.append(
						(String) style
								.getStyleProperty(ICSSPropertyID.ATTR_FONT_STYLE))
				.append(";");
		sb.append(ICSSPropertyID.ATTR_FONT_WEIGHT).append(":");
		sb.append(
				((Integer) style
						.getStyleProperty(ICSSPropertyID.ATTR_FONT_WEIGHT))
						.toString()).append(";");
		sb.append(ICSSPropertyID.ATTR_FONT_SIZE).append(":");
		int fontSize = getFontSize(style, style
				.getStyleProperty(ICSSPropertyID.ATTR_FONT_SIZE));
		sb.append(Integer.toString(fontSize));
		return sb.toString();
	}

	public ICSSFont createFont(ICSSStyle style) {
		String fontfamily = (String) style
				.getStyleProperty(ICSSPropertyID.ATTR_FONT_FAMILY);
		Object fontsizeobj = style
				.getStyleProperty(ICSSPropertyID.ATTR_FONT_SIZE);
		int fontsize;
		fontsize = getFontSize(style, fontsizeobj);
		int fontstyle = getFontStyle(style);
		int fontweight = ((Integer) style
				.getStyleProperty(ICSSPropertyID.ATTR_FONT_WEIGHT)).intValue();

		return new CSSFont(fontfamily, fontsize, fontstyle, fontweight,
				resolveFontStyleString(style));
	}

	private int getFontSize(ICSSStyle style, Object fontsizeobj) {
		int fontsize;
		if (fontsizeobj instanceof Length) {
			fontsize = ((Length) fontsizeobj).getValue();
		} else {
			fontsize = style.getParentStyle().getCSSFont().getFontSize();
		}
		return fontsize;
	}

	/**
	 * @param style
	 */
	private int getFontStyle(ICSSStyle style) {
		int fontstyle;
		String fontstylestr = (String) style
				.getStyleProperty(ICSSPropertyID.ATTR_FONT_STYLE);
		if (ICSSPropertyID.VAL_ITALIC.equals(fontstylestr)
				|| ICSSPropertyID.VAL_OBLIQUE.equals(fontstylestr)) {
			fontstyle = SWT.ITALIC;
		} else {
			fontstyle = SWT.NORMAL;
		}
		return fontstyle;
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.jst.pagedesigner.css2.font.ICSSFontManager#dispose()
	 */
	public void dispose() {
		_cacheManager.disposeAll();
	}

	/**
	 * @return the default css font
	 */
	public ICSSFont createDefaultFont() {
		CSSFont result = new CSSFont(FontFamilyMeta.DEFAULT_FONT,
				(int) FontSizeMeta.MEDIUM_VAL_INT, SWT.NORMAL,
				FontWeightMeta.NORMAL_WEIGHT.intValue(), "");
		return result;
	}

	/**
	 * @param f
	 * @return the swt font for f
	 */
	public Font getSwtFont(CSSFont f) {
		return (Font) _cacheManager.getEntry(f);
	}

	/**
	 * @return the singleton font manager
	 */
	public static CSSFontManager getInstance() {
		if (_instance == null) {
			_instance = new CSSFontManager();
		}
		return _instance;
	}
}