org.eclipse.nebula.widgets.nattable.core/src/org/eclipse/nebula/widgets/nattable/persistence/StylePersistor.java

/*******************************************************************************
 * Copyright (c) 2012, 2020 Original authors and others.
 *
 * This program and the accompanying materials are made
 * available under the terms of the Eclipse Public License 2.0
 * which is available at https://www.eclipse.org/legal/epl-2.0/
 *
 * SPDX-License-Identifier: EPL-2.0
 *
 * Contributors:
 *     Original authors and others - initial API and implementation
 ******************************************************************************/
package org.eclipse.nebula.widgets.nattable.persistence;

import static org.eclipse.nebula.widgets.nattable.persistence.IPersistable.DOT;
import static org.eclipse.nebula.widgets.nattable.style.CellStyleAttributes.BACKGROUND_COLOR;
import static org.eclipse.nebula.widgets.nattable.style.CellStyleAttributes.BORDER_STYLE;
import static org.eclipse.nebula.widgets.nattable.style.CellStyleAttributes.FONT;
import static org.eclipse.nebula.widgets.nattable.style.CellStyleAttributes.FOREGROUND_COLOR;
import static org.eclipse.nebula.widgets.nattable.style.CellStyleAttributes.HORIZONTAL_ALIGNMENT;
import static org.eclipse.nebula.widgets.nattable.style.CellStyleAttributes.VERTICAL_ALIGNMENT;

import java.util.Properties;

import org.eclipse.nebula.widgets.nattable.style.BorderStyle;
import org.eclipse.nebula.widgets.nattable.style.CellStyleAttributes;
import org.eclipse.nebula.widgets.nattable.style.HorizontalAlignmentEnum;
import org.eclipse.nebula.widgets.nattable.style.Style;
import org.eclipse.nebula.widgets.nattable.style.VerticalAlignmentEnum;
import org.eclipse.nebula.widgets.nattable.util.GUIHelper;
import org.eclipse.swt.graphics.Color;
import org.eclipse.swt.graphics.Font;
import org.eclipse.swt.graphics.FontData;

/**
 * Saves and loads the following components of a style to a properties object. -
 * Foreground color - Background color - Horizontal alignment - Vertical
 * alignment - Font - Border style
 */
public final class StylePersistor {

    private StylePersistor() {
        // private default constructor for helper class
    }

    // Style prefix constants
    public static final String STYLE_PERSISTENCE_PREFIX = "style"; //$NON-NLS-1$
    public static final String BLUE_COLOR_PREFIX = "blue"; //$NON-NLS-1$
    public static final String GREEN_COLOR_PREFIX = "green"; //$NON-NLS-1$
    public static final String RED_COLOR_PREFIX = "red"; //$NON-NLS-1$
    public static final String V_ALIGNMENT_PREFIX = "verticalAlignment"; //$NON-NLS-1$
    public static final String H_ALIGNMENT_PREFIX = "horizontalAlignment"; //$NON-NLS-1$
    public static final String BG_COLOR_PREFIX = "bg"; //$NON-NLS-1$
    public static final String FG_COLOR_PREFIX = "fg"; //$NON-NLS-1$
    public static final String FONT_PREFIX = "font"; //$NON-NLS-1$
    public static final String BORDER_PREFIX = "border"; //$NON-NLS-1$

    // Save

    public static void saveStyle(String prefix, Properties properties,
            Style style) {
        prefix = prefix + DOT + STYLE_PERSISTENCE_PREFIX;

        saveColor(prefix + DOT + BG_COLOR_PREFIX, properties,
                style.getAttributeValue(BACKGROUND_COLOR));
        saveColor(prefix + DOT + FG_COLOR_PREFIX, properties,
                style.getAttributeValue(FOREGROUND_COLOR));

        saveHAlign(prefix, properties,
                style.getAttributeValue(HORIZONTAL_ALIGNMENT));
        saveVAlign(prefix, properties,
                style.getAttributeValue(VERTICAL_ALIGNMENT));

        saveFont(prefix, properties, style.getAttributeValue(FONT));

        saveBorder(prefix, properties, style.getAttributeValue(BORDER_STYLE));
    }

    protected static void saveVAlign(String prefix, Properties properties,
            VerticalAlignmentEnum vAlign) {
        if (vAlign == null) {
            return;
        }
        properties
                .setProperty(prefix + DOT + V_ALIGNMENT_PREFIX, vAlign.name());
    }

    protected static void saveHAlign(String prefix, Properties properties,
            HorizontalAlignmentEnum hAlign) {
        if (hAlign == null) {
            return;
        }
        properties
                .setProperty(prefix + DOT + H_ALIGNMENT_PREFIX, hAlign.name());
    }

    protected static void saveBorder(String prefix, Properties properties,
            BorderStyle borderStyle) {
        if (borderStyle == null) {
            return;
        }
        properties.setProperty(prefix + DOT + BORDER_PREFIX,
                String.valueOf(borderStyle.toString()));
    }

    protected static void saveFont(String prefix, Properties properties,
            Font font) {
        if (font == null) {
            return;
        }
        properties.setProperty(prefix + DOT + FONT_PREFIX,
                String.valueOf(font.getFontData()[0].toString()));
    }

    protected static void saveColor(String prefix, Properties properties,
            Color color) {
        if (color == null) {
            return;
        }
        ColorPersistor.saveColor(prefix, properties, color);
    }

    // Load

    public static Style loadStyle(String prefix, Properties properties) {
        Style style = new Style();
        prefix = prefix + DOT + STYLE_PERSISTENCE_PREFIX;

        // BG Color
        String bgColorPrefix = prefix + DOT + BG_COLOR_PREFIX;
        Color bgColor = loadColor(bgColorPrefix, properties);
        if (bgColor != null) {
            style.setAttributeValue(CellStyleAttributes.BACKGROUND_COLOR,
                    bgColor);
        }

        // FG Color
        String fgColorPrefix = prefix + DOT + FG_COLOR_PREFIX;
        Color fgColor = loadColor(fgColorPrefix, properties);
        if (fgColor != null) {
            style.setAttributeValue(CellStyleAttributes.FOREGROUND_COLOR,
                    fgColor);
        }

        // Alignment
        String hAlignPrefix = prefix + DOT + H_ALIGNMENT_PREFIX;
        HorizontalAlignmentEnum hAlign = loadHAlignment(hAlignPrefix,
                properties);
        if (hAlign != null) {
            style.setAttributeValue(CellStyleAttributes.HORIZONTAL_ALIGNMENT,
                    hAlign);
        }

        String vAlignPrefix = prefix + DOT + V_ALIGNMENT_PREFIX;
        VerticalAlignmentEnum vAlign = loadVAlignment(vAlignPrefix, properties);
        if (vAlign != null) {
            style.setAttributeValue(CellStyleAttributes.VERTICAL_ALIGNMENT,
                    vAlign);
        }

        // Font
        String fontPrefix = prefix + DOT + FONT_PREFIX;
        Font font = loadFont(fontPrefix, properties);
        if (font != null) {
            style.setAttributeValue(CellStyleAttributes.FONT, font);
        }

        // Border Style
        String borderPrefix = prefix + DOT + BORDER_PREFIX;
        BorderStyle borderStyle = loadBorderStyle(borderPrefix, properties);
        if (borderStyle != null) {
            style.setAttributeValue(CellStyleAttributes.BORDER_STYLE,
                    borderStyle);
        }

        return style;
    }

    private static BorderStyle loadBorderStyle(String borderPrefix,
            Properties properties) {
        String borderStyle = properties.getProperty(borderPrefix);
        if (borderStyle != null) {
            return new BorderStyle(borderStyle);
        }
        return null;
    }

    private static Font loadFont(String fontPrefix, Properties properties) {
        String fontdata = properties.getProperty(fontPrefix);
        if (fontdata != null) {
            return GUIHelper.getFont(new FontData(fontdata));
        }
        return null;
    }

    private static HorizontalAlignmentEnum loadHAlignment(String hAlignPrefix,
            Properties properties) {
        String enumName = properties.getProperty(hAlignPrefix);
        if (enumName != null) {
            return HorizontalAlignmentEnum.valueOf(enumName);
        }
        return null;
    }

    private static VerticalAlignmentEnum loadVAlignment(String vAlignPrefix,
            Properties properties) {
        String enumName = properties.getProperty(vAlignPrefix);
        if (enumName != null) {
            return VerticalAlignmentEnum.valueOf(enumName);
        }
        return null;
    }

    protected static Color loadColor(String prefix, Properties properties) {
        return ColorPersistor.loadColor(prefix, properties);
    }
}