/**
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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.wave;
import com.google.common.base.Preconditions;
import org.waveprotocol.wave.client.editor.content.ContentDocument;
import org.waveprotocol.wave.client.editor.content.DiffHighlightingFilter;
import org.waveprotocol.wave.model.document.operation.DocInitialization;
import org.waveprotocol.wave.model.document.operation.DocOp;
import org.waveprotocol.wave.model.operation.OperationException;
import org.waveprotocol.wave.model.operation.OperationRuntimeException;
/**
* Wraps a {@link ContentDocument}, exposing its diff highlighting capabilities
* in the language of a {@link DiffSink}.
*
* @author hearnden@google.com (David Hearnden)
*/
public final class DiffContentDocument implements DiffSink {
/** Regular document. */
private final ContentDocument document;
/** Sink that highlights ops that it consumes. */
private final DiffHighlightingFilter differ;
/** True when there are consumed diffs that have not been cleared. */
private boolean hasDiffs;
private DiffContentDocument(ContentDocument document, DiffHighlightingFilter differ) {
this.document = document;
this.differ = differ;
}
/**
* Creates a diff-handling wrapper for a content document.
*/
public static DiffContentDocument create(ContentDocument doc) {
DiffHighlightingFilter differ = new DiffHighlightingFilter(doc.getDiffTarget());
return new DiffContentDocument(doc, differ);
}
@Override
public void consume(DocOp op) {
Preconditions.checkState(!hasDiffs);
document.consume(op);
}
@Override
public void consumeAsDiff(DocOp op) {
try {
differ.consume(op);
} catch (OperationException e) {
throw new OperationRuntimeException("error applying diff op", e);
}
hasDiffs = true;
}
@Override
public void clearDiffs() {
differ.clearDiffs();
hasDiffs = false;
}
@Override
public DocInitialization asOperation() {
return document.asOperation();
}
/** @return the underlying document. */
ContentDocument getDocument() {
return document;
}
}