/*******************************************************************************
 * Copyright (c) 2004, 2016 IBM Corporation and others.
 *
 * This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License 2.0
 * which accompanies this distribution, and is available at
 * https://www.eclipse.org/legal/epl-2.0/
 *
 * SPDX-License-Identifier: EPL-2.0
 *
 * Contributors:
 *     IBM Corporation - initial API and implementation
 *******************************************************************************/

package org.eclipse.ui.internal.intro.impl.model;

import org.eclipse.ui.internal.intro.impl.model.util.BundleUtil;
import org.eclipse.ui.internal.intro.impl.util.Log;
import org.osgi.framework.Bundle;
import org.w3c.dom.Element;
import org.w3c.dom.NodeList;

/**
 * An intro HTML element. Can have text and image as fall back. "type" attribute
 * in markup determines if it is inlined or not. if inlined, value of 'src' will
 * be treated as a snippet of HTML to emit 'in-place'. If 'embed', a valid
 * (full) HTML document will be embedded using HTML 'OBJECT' tag. Ecoding can be
 * specified for inline snippets.
 */
public class IntroHTML extends AbstractTextElement {

    protected static final String TAG_HTML = "html"; //$NON-NLS-1$

    private static final String ATT_SRC = "src"; //$NON-NLS-1$
    /**
     * type must be "inline" or "embed".
     */
    private static final String ATT_TYPE = "type"; //$NON-NLS-1$
    // Default is UTF-8.
    private static final String ATT_ENCODING = "encoding"; //$NON-NLS-1$

    private String src;
    private String html_type;
    private String encoding;
    private IntroImage introImage;

    IntroHTML(Element element, Bundle bundle, String base) {
        super(element, bundle);
        src = getAttribute(element, ATT_SRC);
        html_type = getAttribute(element, ATT_TYPE);
        encoding = getAttribute(element, ATT_ENCODING);
        if (encoding == null)
            encoding = "UTF-8"; //$NON-NLS-1$
        if (html_type != null && !html_type.equalsIgnoreCase("inline") //$NON-NLS-1$
                && !html_type.equalsIgnoreCase("embed")) //$NON-NLS-1$
            // if type is not correct, null it.
            html_type = null;

        // description will be null if there is no description element.
        introImage = getIntroImage(element, base);

        // Resolve.
        src = BundleUtil.getResolvedResourceLocation(base, src, bundle);
    }

    /**
     * Retruns the intro image element embedded in this element.
     */
    private IntroImage getIntroImage(Element element, String base) {
        try {
            // There should only be one text element. Since elements where
            // obtained by name, no point validating name.
            NodeList imageElements = element
                .getElementsByTagName(IntroImage.TAG_IMAGE);
            if (imageElements.getLength() == 0)
                // no contributions. done.
                return null;
            IntroImage image = new IntroImage((Element) imageElements.item(0),
                getBundle(), base);
            image.setParent(this);
            return image;
        } catch (Exception e) {
            Log.error(e.getMessage(), e);
            return null;
        }
    }

    /**
     * Returns the html type. Will be either "inline" or "embed". If not, null
     * will be returned as if the attibute was nto defined.
     *
     * @return Returns the html type value.
     */
    public boolean isInlined() {
        return (html_type != null && html_type.equalsIgnoreCase("inline")) ? true //$NON-NLS-1$
                : false;
    }

    /**
     * @return Returns the src.
     */
    public String getSrc() {
        return src;
    }

    /**
     * @return Returns the encoding of the inlined file. This is not needed for
     *         embedded files. Default is UTF-8.
     */
    public String getInlineEncoding() {
        return encoding;
    }

    /**
     * Returns the intro image used as a replacement if this HTML element fails.
     * May return null if there is no image child.
     *
     * @return Returns the introImage.
     */
    public IntroImage getIntroImage() {
        return introImage;
    }

    @Override
	public int getType() {
        return AbstractIntroElement.HTML;
    }

    /**
     * Deep copy since class has mutable objects.
     */
    @Override
	public Object clone() throws CloneNotSupportedException {
        IntroHTML clone = (IntroHTML) super.clone();
        if (introImage != null) {
            IntroImage cloneIntroImage = (IntroImage) introImage.clone();
            cloneIntroImage.setParent(clone);
            clone.introImage = cloneIntroImage;
        }
        return clone;
    }

}
