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/*
* This library is part of OpenCms -
* the Open Source Content Management System
*
* Copyright (c) Alkacon Software GmbH & Co. KG (http://www.alkacon.com)
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library 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
* Lesser General Public License for more details.
*
* For further information about Alkacon Software, please see the
* company website: http://www.alkacon.com
*
* For further information about OpenCms, please see the
* project website: http://www.opencms.org
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
package org.opencms.ade.galleries.client.preview;
import org.opencms.ade.galleries.client.preview.ui.CmsImagePreviewDialog;
import org.opencms.ade.galleries.shared.CmsImageInfoBean;
import org.opencms.gwt.client.CmsCoreProvider;
import org.opencms.gwt.client.util.CmsClientStringUtil;
import org.opencms.gwt.client.util.I_CmsSimpleCallback;
import org.opencms.util.CmsStringUtil;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import com.google.gwt.event.logical.shared.ValueChangeEvent;
import com.google.gwt.event.logical.shared.ValueChangeHandler;
import com.google.gwt.user.client.ui.Image;
import com.google.gwt.user.client.ui.Widget;
import elemental2.dom.HTMLImageElement;
import jsinterop.base.Js;
/**
* Image preview dialog controller handler.
*
* Delegates the actions of the preview controller to the preview dialog.
*
* @since 8.0.0
*/
public class CmsImagePreviewHandler extends A_CmsPreviewHandler
implements ValueChangeHandler {
/** Enumeration of image tag attribute names. */
public enum Attribute {
/** Image align attribute. */
align,
/** Image alt attribute. */
alt,
/** Image class attribute. */
clazz,
/** Image copyright info. */
copyright,
/** Image direction attribute. */
dir,
/** No image selected if this attribute is present. */
emptySelection,
/** The image hash. */
hash,
/** Image height attribute. */
height,
/** Image hspace attribute. */
hspace,
/** Image id attribute. */
id,
/** Image copyright flag. */
insertCopyright,
/** Image link original flag. */
insertLinkOrig,
/** Image spacing flag. */
insertSpacing,
/** Image subtitle flag. */
insertSubtitle,
/** Image language attribute. */
lang,
/** Image link path. */
linkPath,
/** Image link target. */
linkTarget,
/** Image longDesc attribute. */
longDesc,
/** Image style attribute. */
style,
/** Image title attribute. */
title,
/** Image vspace attribute. */
vspace,
/** Image width attribute. */
width
}
/**
* Encapsulates information used to update the preview image's scaling parameters.
*/
public static class PreviewImageUpdate {
/** Normal height. */
private int m_height;
/** High resolution scaling parameters. */
private String m_highResPreview;
/** Normal preview scaling parameters. */
private String m_preview;
/** Normal width. */
private int m_width;
/**
* Creates a new instance.
*
* @param preview the normal preview scaling parameters
* @param highResPreview the high resolution scaling parameters
* @param width the normal width
* @param height the normal height
*/
public PreviewImageUpdate(String preview, String highResPreview, int width, int height) {
super();
m_preview = preview;
m_highResPreview = highResPreview;
m_width = width;
m_height = height;
}
/**
* Updates the given image with information from this object.
*
* @param image the image to update
* @param src the image base URL
* @param isSvg true if the image is an SVG
*/
public void applyToImage(Image image, String src, boolean isSvg, Widget container) {
HTMLImageElement imgElement = Js.cast(image.getElement());
long time = System.currentTimeMillis();
if (!isSvg) {
int parentWidth = container.getElement().getClientWidth();
int parentHeight = container.getElement().getClientHeight();
int effectiveWidth = m_width;
if ((parentWidth > effectiveWidth) && ((parentWidth - effectiveWidth) <= 3)) {
effectiveWidth = parentWidth;
}
int effectiveHeight = m_height;
if ((parentHeight > effectiveHeight) && ((parentHeight - effectiveHeight) <= 3)) {
effectiveHeight = parentHeight;
}
imgElement.setAttribute("width", "" + effectiveWidth);
imgElement.setAttribute("height", "" + effectiveHeight);
}
imgElement.src = src + "?" + appendQuality(m_preview) + "&time=" + time;
imgElement.removeAttribute("srcset");
if (!isSvg) {
if (m_highResPreview != null) {
imgElement.srcset = src + "?" + appendQuality(m_highResPreview) + "&time=" + time + " 2x";
}
}
}
}
/** The image container height. */
private int m_containerHeight;
/** The image container width. */
private int m_containerWidth;
/** List of handlers for cropping changes. */
private List m_croppingHandlers = new ArrayList<>();
/** The cropping parameter. */
private CmsCroppingParamBean m_croppingParam;
/** The image format handler. */
private CmsImageFormatHandler m_formatHandler;
/** List of handlers for focal point changes. */
private List m_imagePointHandlers = new ArrayList<>();
/** The focal point controller. */
private CmsFocalPointController m_pointController;
/** The preview dialog. */
private CmsImagePreviewDialog m_previewDialog;
/**
* Constructor.
*
* @param resourcePreview the resource preview instance
*/
public CmsImagePreviewHandler(CmsImageResourcePreview resourcePreview) {
super(resourcePreview);
m_previewDialog = resourcePreview.getPreviewDialog();
m_pointController = new CmsFocalPointController(
() -> m_croppingParam,
this::getImageInfo,
this::onImagePointChanged);
}
/**
* Appends quality parameter to a set of scaling parameters, unless the input is the empty string or already contains a quality parameter.
*
* @param text the input scaling parameters
* @return the modified scaling parameters
*/
public static final String appendQuality(String text) {
if (CmsStringUtil.isEmpty(text) || text.contains("q:")) {
return text;
} else {
return text + ",q:85";
}
}
/**
* Adds a handler for cropping changes.
*
* @param action the handler to add
*/
public void addCroppingChangeHandler(Runnable action) {
m_croppingHandlers.add(action);
}
/**
* Adds a handler for focal point changes.
*
* @param onImagePointChanged the handler to add
*/
public void addImagePointChangeHandler(Runnable onImagePointChanged) {
m_imagePointHandlers.add(onImagePointChanged);
}
/**
* Returns the image cropping parameter bean.
*
* @return the image cropping parameter bean
*/
public CmsCroppingParamBean getCroppingParam() {
return m_croppingParam;
}
/**
* Gets the focal point controller.
*
* @return the focal point controller
*/
public CmsFocalPointController getFocalPointController() {
return m_pointController;
}
/**
* Gets the format handler.
*
* @return the format handler
*/
public CmsImageFormatHandler getFormatHandler() {
return m_formatHandler;
}
/**
* Returns the name of the currently selected image format.
*
* @return the format name
*/
public String getFormatName() {
String result = "";
if ((m_formatHandler != null) && (m_formatHandler.getCurrentFormat() != null)) {
result = m_formatHandler.getCurrentFormat().getName();
}
return result;
}
/**
* Returns image tag attributes to set for editor plugins.
*
* @param callback the callback to execute
*/
public void getImageAttributes(I_CmsSimpleCallback> callback) {
Map result = new HashMap();
result.put(Attribute.hash.name(), String.valueOf(getImageIdHash()));
m_formatHandler.getImageAttributes(result);
m_previewDialog.getImageAttributes(result, callback);
}
/**
* Returns the structure id hash of the previewed image.
*
* @return the structure id hash
*/
public int getImageIdHash() {
return m_resourceInfo.getHash();
}
/**
* Gets the image information.
*
* @return the image information
*/
public CmsImageInfoBean getImageInfo() {
return m_resourceInfo;
}
/**
* Gets the information to update the preview image.
*
* @param imageHeight the original image height
* @param imageWidth the original image width
* @return the preview update information
*/
public PreviewImageUpdate getPreviewImageUpdate(int imageHeight, int imageWidth) {
String lowRes = getPreviewScaleParam(imageHeight, imageWidth, 1);
String highRes = getPreviewScaleParam(imageHeight, imageWidth, 2);
Map lowResMap = parseScalingParams(lowRes);
int wLow = getScalerParameter(lowResMap, "w", imageWidth);
int hLow = getScalerParameter(lowResMap, "h", imageHeight);
return new PreviewImageUpdate(lowRes, highRes, wLow, hLow);
}
/**
* Returns the cropping parameter.
*
* @param imageHeight the original image height
* @param imageWidth the original image width
* @param density the pixel density (acts as a multiplier for available space)
*
* @return the cropping parameter
*/
public String getPreviewScaleParam(int imageHeight, int imageWidth, int density) {
int maxHeight = m_containerHeight * density;
int maxWidth = m_containerWidth * density;
if ((m_croppingParam != null) && (m_croppingParam.isCropped() || m_croppingParam.isScaled())) {
// NOTE: getREstrictedSizeScaleParam does not work correctly if there isn't actually any cropping/scaling, so we explicitly don't use it in this case
return m_croppingParam.getRestrictedSizeScaleParam(maxHeight, maxWidth);
}
if ((imageHeight <= maxHeight) && (imageWidth <= maxWidth)) {
return ""; // dummy parameter, doesn't actually do anything
}
CmsCroppingParamBean restricted = new CmsCroppingParamBean();
boolean tooHigh = imageHeight > maxHeight;
boolean tooWide = imageWidth > maxWidth;
double shrinkX = (1.0 * imageWidth) / maxWidth;
double shrinkY = (1.0 * imageHeight) / maxHeight;
double aspectRatio = (1.0 * imageWidth) / imageHeight;
if (tooHigh && tooWide) {
if (shrinkX > shrinkY) {
restricted.setTargetWidth(maxWidth);
restricted.setTargetHeight((int)(maxWidth / aspectRatio));
} else {
restricted.setTargetHeight(maxHeight);
restricted.setTargetWidth((int)(maxHeight * aspectRatio));
}
} else if (tooWide) {
restricted.setTargetWidth(maxWidth);
restricted.setTargetHeight((int)(maxWidth / aspectRatio));
} else if (tooHigh) {
restricted.setTargetHeight(maxHeight);
restricted.setTargetWidth((int)(maxHeight * aspectRatio));
} else {
restricted.setTargetWidth(imageWidth);
restricted.setTargetHeight(imageHeight);
}
return restricted.toString();
}
/**
* @see com.google.gwt.event.logical.shared.ValueChangeHandler#onValueChange(com.google.gwt.event.logical.shared.ValueChangeEvent)
*/
public void onValueChange(ValueChangeEvent event) {
m_croppingParam = event.getValue();
String viewLink = m_resourcePreview.getViewLink();
if (viewLink == null) {
viewLink = CmsCoreProvider.get().link(m_resourcePreview.getResourcePath());
}
PreviewImageUpdate previewUpdate = getPreviewImageUpdate(
m_croppingParam.getOrgHeight(),
m_croppingParam.getOrgWidth());
boolean isSvg = CmsClientStringUtil.checkIsPathOrLinkToSvg(m_resourcePreview.getResourcePath());
previewUpdate.applyToImage(
m_previewDialog.getPreviewImage(),
viewLink,
isSvg,
m_previewDialog.getPreviewImage().getParent());
onCroppingChanged();
}
/**
* Sets the image format handler.
*
* @param formatHandler the format handler
*/
public void setFormatHandler(CmsImageFormatHandler formatHandler) {
m_formatHandler = formatHandler;
m_croppingParam = m_formatHandler.getCroppingParam();
m_formatHandler.addValueChangeHandler(this);
onCroppingChanged();
}
/**
*
* Sets the dimensions of the area the image is going to be placed in.
*
* @param offsetWidth the container width
* @param offsetHeight the container height
*/
public void setImageContainerSize(int offsetWidth, int offsetHeight) {
m_containerWidth = offsetWidth;
m_containerHeight = offsetHeight;
}
/**
* Helper method for getting an integer-valued scaler parameter from a map of parameters, with a default value that should be returned if the map doesn't contain the parameter.
*
* @param scalerParams the map of scaler parameters
* @param key the map key
* @param defaultValue the value to return if the map doesn't contain a value for the key
*
* @return the value of the scaler parameter
*/
private int getScalerParameter(Map scalerParams, String key, int defaultValue) {
String value = scalerParams.get(key);
if (value != null) {
return Integer.parseInt(value);
} else {
return defaultValue;
}
}
/**
* Calls all cropping change handlers.
*/
private void onCroppingChanged() {
for (Runnable action : m_croppingHandlers) {
action.run();
}
}
/**
* Calls all focal point change handlers.
*/
private void onImagePointChanged() {
for (Runnable handler : m_imagePointHandlers) {
handler.run();
}
}
/**
* Parse scaling parameters as a map.
*
* @param params the scaling parameters
* @return the scaling parameters as a map
*/
private Map parseScalingParams(String params) {
final String prefix = "__scale=";
if (params.startsWith(prefix)) {
params = params.substring(prefix.length());
}
return CmsStringUtil.splitAsMap(params, ",", ":");
}
}