ColorAndFontService.java

package org.csstudio.sds.ui.internal.editor.newproperties.colorservice;

import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.util.Collections;
import java.util.List;

import javax.xml.parsers.SAXParser;
import javax.xml.parsers.SAXParserFactory;

import org.csstudio.sds.internal.preferences.PreferenceConstants;
import org.csstudio.sds.ui.SdsUiPlugin;
import org.csstudio.sds.util.ColorAndFontUtil;
import org.csstudio.ui.util.CustomMediaFactory;
import org.eclipse.core.resources.IFile;
import org.eclipse.swt.SWT;
import org.eclipse.swt.graphics.Color;
import org.eclipse.swt.graphics.Font;
import org.eclipse.swt.graphics.FontData;
import org.eclipse.swt.graphics.RGB;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 * 
 * @author Sven Wende (C1 WPS), Kai Meyer (C1 WPS)
 * 
 */
public class ColorAndFontService implements IColorAndFontService {
    private static final Logger LOG = LoggerFactory.getLogger(ColorAndFontService.class);

	private static RGB FALLBACK_COLOR = new RGB(255, 0, 0);
	private static FontData FALLBACK_FONT = new FontData("Arial", 8, SWT.None);

	private IFile _file;
	private long _currentTimeStamp = -1;
	private AbstractColorAndFontHandler _colorAndFontSaxHandler;

	public ColorAndFontService(IFile file, AbstractColorAndFontHandler handler) {
		assert file != null : "file != null";
		assert handler != null : "handler != null";
		
		_file = file;
		_colorAndFontSaxHandler = handler;
	}

	private void checkForUpdate() {
		long modificationStamp = _file.getModificationStamp();
		if (_currentTimeStamp > modificationStamp) {
			_colorAndFontSaxHandler.reset();
			_currentTimeStamp = modificationStamp;
		} else if (_currentTimeStamp < modificationStamp) {
			InputStream inputStream = null;
			try {
				File path = _file.getLocation().toFile();
				inputStream = new FileInputStream(path);
				SAXParser parser = SAXParserFactory.newInstance()
						.newSAXParser();

				parser.parse(inputStream, _colorAndFontSaxHandler);
				_currentTimeStamp = modificationStamp;
			} catch (Exception e) {
				LOG.debug(e.toString());
			} finally {
				closeStream(inputStream);
			}
		}
	}

	private void closeStream(InputStream stream) {
		if (stream != null) {
			try {
				stream.close();
			} catch (IOException e) {
				LOG.debug(e.toString());
			}
		}
	}

	private NamedStyle getSelectedStyle() {
		String styleName = SdsUiPlugin.getCorePreferenceStore().getString(
				PreferenceConstants.PROP_SELECTED_COLOR_AND_FONT_STYLE);
		return _colorAndFontSaxHandler.getStyle(styleName);
	}

	@Override
	public Font getFont(String fontOrVariable) {
		FontData fd = null;

		if (ColorAndFontUtil.isVariable(fontOrVariable)) {
			checkForUpdate();
			NamedStyle selectedStyle = getSelectedStyle();
			if (selectedStyle != null) {
				NamedFont nf = selectedStyle.getFont(fontOrVariable);

				if (nf != null) {
					fd = nf.getFontData();
				}
			}
		} else {
			fd = toFontData(fontOrVariable);
		}

		// .. fallback
		if (fd == null) {
			fd = FALLBACK_FONT;
		}

		assert fd != null;

		return CustomMediaFactory.getInstance().getFont(fd);
	}

	@Override
	public Color getColor(String hexOrVariable) {
		assert hexOrVariable != null;

		RGB rgb = null;

		if (ColorAndFontUtil.isVariable(hexOrVariable)) {
			checkForUpdate();
			NamedStyle selectedStyle = getSelectedStyle();
			if (selectedStyle != null) {
				NamedColor namedColor = selectedStyle.getColor(hexOrVariable);
				rgb = namedColor != null ? namedColor.getRgb() : FALLBACK_COLOR;
			}
		} else if (ColorAndFontUtil.isHex(hexOrVariable)) {
			rgb = toRgb(hexOrVariable);
		}

		// .. fallback
		if (rgb == null) {
			rgb = FALLBACK_COLOR;
		}

		assert rgb != null;

		return CustomMediaFactory.getInstance().getColor(rgb);
	}

	@Override
	public List<NamedColor> listAvailableColors() {
		checkForUpdate();
		NamedStyle selectedStyle = getSelectedStyle();
		if (selectedStyle != null) {
			return selectedStyle.listAllColors();
		} else {
			return Collections.emptyList();
		}
	}

	@Override
	public List<NamedFont> listAvailableFonts() {
		checkForUpdate();
		NamedStyle selectedStyle = getSelectedStyle();
		if (selectedStyle != null) {
			return selectedStyle.listAllFonts();
		} else {
			return Collections.emptyList();
		}
	}

	@Override
	public List<NamedStyle> getStyles() {
		checkForUpdate();
		return _colorAndFontSaxHandler.getStyles();
	}

	private FontData toFontData(String font) {
		assert font != null;

		String[] tmp = font.split(",");

		String fontName = "Arial";
		int size = -1;
		boolean bold = false;
		boolean italic = false;

		// .. resolve name
		if (tmp.length > 0) {
			fontName = tmp[0].trim();
		}

		// .. resolve size
		if (tmp.length > 1) {

			try {
				size = Integer.parseInt(tmp[1].trim());
			} catch (NumberFormatException nfd) {
			}
		}

		// .. resolve bold / italic
		if (tmp.length > 2) {
			for (int i = 2; i < tmp.length; i++) {
				if ("bold".equalsIgnoreCase(tmp[i].trim())) {
					bold = true;
				} else if ("italic".equalsIgnoreCase(tmp[i].trim())) {
					italic = true;
				}
			}
		}

		FontData fd = new FontData();

		// .. font type
		fd.setName(fontName);

		// .. height
		if (size > 0) {
			fd.setHeight(size);
		}

		// .. style
		int style = SWT.None;

		if (bold) {
			style |= SWT.BOLD;
		}
		if (italic) {
			style |= SWT.ITALIC;
		}
		fd.setStyle(style);

		return fd;
	}

	private RGB toRgb(String hex) {
		assert ColorAndFontUtil.isHex(hex);
		int r = Integer.valueOf(hex.substring(1, 3), 16);
		int g = Integer.valueOf(hex.substring(3, 5), 16);
		int b = Integer.valueOf(hex.substring(5, 7), 16);
		return new RGB(r, g, b);
	}
}