/**
* Copyright 2009 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.editor.content.paragraph;
import com.google.common.annotations.VisibleForTesting;
import com.google.gwt.dom.client.Element;
import org.waveprotocol.wave.client.editor.RenderingMutationHandler;
import org.waveprotocol.wave.client.editor.content.ContentElement;
import org.waveprotocol.wave.client.editor.content.ContentNode;
import org.waveprotocol.wave.client.editor.content.paragraph.Paragraph.Alignment;
import org.waveprotocol.wave.client.editor.content.paragraph.Paragraph.Direction;
import org.waveprotocol.wave.client.scheduler.FinalTaskRunner;
import org.waveprotocol.wave.client.scheduler.FinalTaskRunnerImpl;
import org.waveprotocol.wave.client.scheduler.Scheduler;
import org.waveprotocol.wave.model.util.CollectionUtils;
import org.waveprotocol.wave.model.util.IdentitySet;
import org.waveprotocol.wave.model.util.Preconditions;
/**
* Logic for rendering paragraphs. Exact HTML style decisions are deferred to a
* {@link ParagraphHtmlRenderer}
*
* @author danilatos@google.com (Daniel Danilatos)
*/
public class ParagraphRenderer extends RenderingMutationHandler {
public static ParagraphRenderer create(String nodeletTagname) {
return new ParagraphRenderer(new DefaultParagraphHtmlRenderer(nodeletTagname));
}
private final IdentitySet<ContentElement> elementsToRender =
CollectionUtils.createIdentitySet();
private final OrderedListRenumberer renumberer;
private final FinalTaskRunner runner;
private final Scheduler.Task batchRenderCommand = new Scheduler.Task() {
@Override public void execute() {
while (!elementsToRender.isEmpty()) {
ContentElement e = elementsToRender.someElement();
elementsToRender.remove(e);
render(e);
}
renumberer.renumberAll();
}
private void render(ContentElement p) {
if (p.getImplNodelet() == null) {
// bail if no impl nodelet, the node might be shelved
return;
}
int indent = Paragraph.getIndent(p.getAttribute(Paragraph.INDENT_ATTR));
p.getContext().beginDeferredMutation();
htmlRenderer.updateRendering(p,
p.getAttribute(Paragraph.SUBTYPE_ATTR),
p.getAttribute(Paragraph.LIST_STYLE_ATTR),
indent,
Alignment.fromValue(p.getAttribute(Paragraph.ALIGNMENT_ATTR)),
Direction.fromValue(p.getAttribute(Paragraph.DIRECTION_ATTR)));
p.getContext().endDeferredMutation();
}
};
private final ParagraphHtmlRenderer htmlRenderer;
public ParagraphRenderer(ParagraphHtmlRenderer htmlRenderer) {
this(htmlRenderer, new OrderedListRenumberer(htmlRenderer), new FinalTaskRunnerImpl());
}
@VisibleForTesting
ParagraphRenderer(ParagraphHtmlRenderer htmlRenderer,
OrderedListRenumberer renumberer, FinalTaskRunner finalTaskRunner) {
Preconditions.checkNotNull(htmlRenderer, "Null html renderer");
this.htmlRenderer = htmlRenderer;
this.renumberer = renumberer;
this.runner = finalTaskRunner;
}
@Override
public final Element createDomImpl(Renderable element) {
return htmlRenderer.createDomImpl(element);
}
@Override
public void onAttributeModified(ContentElement p, String name,
String oldValue, String newValue) {
// In case we're in non-render mode
if (p.getImplNodelet() == null && !renumberer.updateHtmlEvenWhenNullImplNodelet) {
return;
}
if (Paragraph.SUBTYPE_ATTR.equals(name) || Paragraph.LIST_STYLE_ATTR.equals(name)) {
ParagraphBehaviour b = ParagraphBehaviour.of(newValue);
scheduleRenderUpdate(p);
scheduleRenumber(p, p.getAttribute(Paragraph.INDENT_ATTR), false);
} else if (Paragraph.INDENT_ATTR.equals(name)) {
scheduleRenderUpdate(p);
scheduleRenumber(p, oldValue, false);
} else if (Paragraph.ALIGNMENT_ATTR.equals(name)) {
scheduleRenderUpdate(p);
} else if (Paragraph.DIRECTION_ATTR.equals(name)) {
scheduleRenderUpdate(p);
}
}
/**
* {@inheritDoc}
*/
@Override
public void onChildAdded(ContentElement p, ContentNode child) {
ParagraphHelper.INSTANCE.onChildAdded(child.getImplNodelet(), p.getImplNodelet());
}
/**
* {@inheritDoc}
*/
@Override
public void onChildRemoved(ContentElement p, ContentNode child) {
ParagraphHelper.INSTANCE.onRemovingChild(child.getImplNodelet(), p.getImplNodelet());
}
@Override
public void onAddedToParent(ContentElement element, ContentElement oldParent) {
scheduleRenumber(element, element.getAttribute(Paragraph.INDENT_ATTR), false);
}
@Override
public void onRemovedFromParent(ContentElement element, ContentElement newParent) {
scheduleRenumber(element, null, true);
}
/**
* {@inheritDoc}
*/
@Override
public void onEmptied(ContentElement p) {
maybeHandleEmptied(p);
}
private void scheduleRenderUpdate(ContentElement p) {
assert p != null;
elementsToRender.add(p);
scheduleBatchRender();
}
private void scheduleRenumber(ContentElement p, String oldIndent, boolean asRemoved) {
if (asRemoved) {
renumberer.markRemoved(p);
} else {
renumberer.markDirty(p, oldIndent);
}
if (renumberer.renumberNeeded()) {
scheduleBatchRender();
}
}
private void scheduleBatchRender() {
runner.scheduleFinally(batchRenderCommand);
}
private void maybeHandleEmptied(ContentElement p) {
if (p.getImplNodelet().getChildCount() == 0) {
ParagraphHelper.INSTANCE.onEmpty(p.getImplNodelet());
}
}
@Override
public void onActivatedSubtree(ContentElement p) {
fanoutAttrs(p);
if (p.getImplNodelet() != null) {
ParagraphHelper.INSTANCE.onRepair(p);
}
}
}