/**
* Copyright 2010 Google Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
*/
package org.waveprotocol.wave.client.clipboard;
import com.google.gwt.dom.client.Document;
import com.google.gwt.dom.client.Element;
import com.google.gwt.dom.client.Node;
import com.google.gwt.dom.client.NodeList;
import com.google.gwt.dom.client.SpanElement;
import com.google.gwt.dom.client.Text;
import com.google.gwt.user.client.Command;
import com.google.gwt.user.client.DeferredCommand;
import org.waveprotocol.wave.client.common.util.DomHelper;
import org.waveprotocol.wave.client.debug.logger.DomLogger;
import org.waveprotocol.wave.client.editor.selection.html.NativeSelectionUtil;
import org.waveprotocol.wave.common.logging.LoggerBundle;
import org.waveprotocol.wave.model.document.RangedAnnotation;
import org.waveprotocol.wave.model.document.util.FocusedPointRange;
import org.waveprotocol.wave.model.document.util.Point;
import org.waveprotocol.wave.model.document.util.PointRange;
import org.waveprotocol.wave.model.document.util.XmlStringBuilder;
/**
* A html clipboard that supports wave metadata: wave xml and annotations
*
* TODO(user): Add high level methods for extracting semantic content from
* clipboard.
*
*/
public class Clipboard {
private static final String MAGIC_CLASSNAME = "__wave_paste";
private static final String WAVE_XML_ATTRIBUTE = "data-wave-xml";
private static final String WAVE_ANNOTATIONS_ATTRIBUTE = "data-wave-annotations";
public static final LoggerBundle LOG = new DomLogger("clipboard");
/**
* Singleton instance of clipboard, there should only be 1 per client.
*/
private static final Clipboard INSTANCE = new Clipboard(PasteBufferImpl.create());
/**
* Underlying pasteBuffer.
*/
private final PasteBufferImpl pasteBuffer;
public static final Clipboard get() {
return INSTANCE;
}
private Clipboard(PasteBufferImpl pasteBuffer) {
this.pasteBuffer = pasteBuffer;
}
/**
* Fill the PasteBuffer with the given content.
*
* This fills the PasteBuffer and sets the selection over the corresponding
* html on the buffer. To fill the clipboard, this needs to be called inside a
* copy event handler, or follow this with an execCommand(copy)
*
* @param htmlFragment
* @param selection
* @param waveXml
* @param normalizedAnnotation
*/
public void fillBufferAndSetSelection(Node htmlFragment, PointRange<Node> selection,
XmlStringBuilder waveXml, Iterable<RangedAnnotation<String>> normalizedAnnotation,
boolean restoreSelection) {
final FocusedPointRange<Node> oldSelection = restoreSelection ? NativeSelectionUtil.get() : null;
// Clear this node and append the cloned fragment.
pasteBuffer.setContent(htmlFragment);
assert htmlFragment.isOrHasChild(selection.getFirst().getContainer()) :
"first not attached before hijack";
assert htmlFragment.isOrHasChild(selection.getSecond().getContainer()) :
"second not attached before hijack";
if (waveXml != null && normalizedAnnotation != null) {
selection =
hijackFragment(waveXml.toString(), AnnotationSerializer
.serializeAnnotation(normalizedAnnotation), selection);
}
assert htmlFragment.isOrHasChild(selection.getFirst().getContainer()) :
"first not attached after hijack";
assert htmlFragment.isOrHasChild(selection.getSecond().getContainer()) :
"second not attached after hijack";
NativeSelectionUtil.set(selection.getFirst(), selection.getSecond());
if (restoreSelection && oldSelection != null) {
DeferredCommand.addCommand(new Command() {
@Override
public void execute() {
NativeSelectionUtil.set(oldSelection);
}
});
}
}
/**
* {@link #fillBufferAndSetSelection(Node, PointRange, XmlStringBuilder, Iterable, boolean)
* same as above, but with the entire fragment. }
*
* @param htmlFragment
* @param waveXml
* @param normalizedAnnotation
*/
public void fillBufferAndSetSelection(Node htmlFragment, XmlStringBuilder waveXml,
Iterable<RangedAnnotation<String>> normalizedAnnotation, boolean restoreSelection) {
Element parent = Document.get().createDivElement();
parent.appendChild(htmlFragment);
PointRange<Node> selection =
new PointRange<Node>(Point.inElement(parent, htmlFragment), Point.<Node> end(parent));
fillBufferAndSetSelection(parent, selection, waveXml, normalizedAnnotation, restoreSelection);
}
/**
* Extract waveXml from this container.
*
* @param srcContainer
*/
public String maybeGetWaveXml(Element srcContainer) {
String waveXml = maybeGetAttributeFromContainer(srcContainer, WAVE_XML_ATTRIBUTE);
String x = srcContainer.getInnerHTML();
if (waveXml != null) {
LOG.trace().logPlainText("found serialized waveXml: " + waveXml);
// NOTE(user): Ensure waveXml does not contain any new line characters.
// FF36+ adds random new lines the attributes
// https://bugzilla.mozilla.org/show_bug.cgi?id=540979
// We filter on all browsers, so they can accept content from FF36.
waveXml = waveXml.replace("\n", "");
}
return waveXml;
}
/**
* Extract serialized annotations from this container.
*
* @param srcContainer
*/
public String maybeGetAnnotations(Element srcContainer) {
String annotations = maybeGetAttributeFromContainer(srcContainer, WAVE_ANNOTATIONS_ATTRIBUTE);
if (annotations != null) {
LOG.trace().log("found serialized annotations: " + annotations);
}
return annotations;
}
private String maybeGetAttributeFromContainer(Element srcContainer, String attribName) {
NodeList<Element> elementsByClassName =
DomHelper.getElementsByClassName(srcContainer, MAGIC_CLASSNAME);
if (elementsByClassName != null && elementsByClassName.getLength() > 0) {
return elementsByClassName.getItem(0).getAttribute(attribName);
}
return null;
}
/**
* Return the underlying paste buffer.
*
* NOTE(user): Paste buffer functionality should be abstracted into this
* class.
*/
public PasteBufferImpl getPasteBuffer() {
return pasteBuffer;
}
/**
* Hijacks the paste fragment by hiding a span with metadata at the end of the
* fragment.
*
* @param xmlInRange The xml string to pass into the magic span element
* @param annotations The annotation string to pass into the magic span
* element
* @param origRange the current range. The span element will be inserted
* before the start
*
* @return The new adjusted selection. The end will be adjusted such that it
* encloses the original selection and the span with metadata
*/
private PointRange<Node> hijackFragment(String xmlInRange, String annotations,
PointRange<Node> origRange) {
Point<Node> origStart = origRange.getFirst();
Point<Node> origEnd = origRange.getSecond();
SpanElement spanForXml = Document.get().createSpanElement();
spanForXml.setAttribute(WAVE_XML_ATTRIBUTE, xmlInRange);
spanForXml.setAttribute(WAVE_ANNOTATIONS_ATTRIBUTE, annotations);
spanForXml.setClassName(MAGIC_CLASSNAME);
LOG.trace().log("original point: " + origStart);
// NOTE(user): An extra span is required at the end for Safari, otherwise
// the span with the metadata may get discarded.
SpanElement trailingSpan = Document.get().createSpanElement();
trailingSpan.setInnerHTML(" ");
if (origEnd.isInTextNode()) {
Text t = (Text) origEnd.getContainer();
t.setData(t.getData().substring(0, origEnd.getTextOffset()));
origEnd.getContainer().getParentElement().insertAfter(spanForXml, t);
origEnd.getContainer().getParentElement().insertAfter(trailingSpan, spanForXml);
} else {
origEnd.getContainer().insertAfter(spanForXml, origEnd.getNodeAfter());
origEnd.getContainer().insertAfter(trailingSpan, spanForXml);
}
Point<Node> newEnd =
Point.<Node> inElement(spanForXml.getParentElement(), trailingSpan.getNextSibling());
LOG.trace().log("new point: " + newEnd);
LOG.trace().logPlainText("parent: " + spanForXml.getParentElement().getInnerHTML());
assert newEnd.getNodeAfter() == null
|| newEnd.getNodeAfter().getParentElement() == newEnd.getContainer() : "inconsistent point";
return new PointRange<Node>(origStart, newEnd);
}
}