/**
* 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.model.document.operation.algorithm;
import org.waveprotocol.wave.model.document.operation.AnnotationBoundaryMap;
import org.waveprotocol.wave.model.document.operation.Attributes;
import org.waveprotocol.wave.model.document.operation.AttributesUpdate;
import org.waveprotocol.wave.model.document.operation.EvaluatingDocOpCursor;
import org.waveprotocol.wave.model.util.ValueUtils;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;
import java.util.TreeMap;
/**
* A normalizer for annotations.
*
* @param <T> the type of the value returned by this normalizer
*/
public final class AnnotationsNormalizer<T> implements EvaluatingDocOpCursor<T> {
private static final class AnnotationChange {
final String key;
final String oldValue;
final String newValue;
AnnotationChange(String key, String oldValue, String newValue) {
this.key = key;
this.oldValue = oldValue;
this.newValue = newValue;
}
}
private static final class AnnotationChangeValues {
final String oldValue;
final String newValue;
AnnotationChangeValues(String oldValue, String newValue) {
this.oldValue = oldValue;
this.newValue = newValue;
}
}
private final EvaluatingDocOpCursor<? extends T> target;
// TODO(danilatos/alexmah): Use efficient StringMap/StringSet,
// and sort on output.
// Even better, optionally don't sort (indexed document doesn't need sorting for its use).
private final Map<String, AnnotationChangeValues> annotationTracker =
new TreeMap<String, AnnotationChangeValues>();
private final Map<String, AnnotationChangeValues> annotationChanges =
new TreeMap<String, AnnotationChangeValues>();
// private final Set<String> ignores = new HashSet<String>();
public AnnotationsNormalizer(EvaluatingDocOpCursor<? extends T> target) {
this.target = target;
}
@Override
public T finish() {
flushAnnotations();
return target.finish();
}
@Override
public void retain(int itemCount) {
if (itemCount > 0) {
flushAnnotations();
target.retain(itemCount);
}
}
@Override
public void characters(String chars) {
if (!chars.isEmpty()) {
flushAnnotations();
target.characters(chars);
}
}
@Override
public void elementStart(String type, Attributes attrs) {
flushAnnotations();
target.elementStart(type, attrs);
}
@Override
public void elementEnd() {
flushAnnotations();
target.elementEnd();
}
@Override
public void deleteCharacters(String chars) {
if (!chars.isEmpty()) {
flushAnnotations();
target.deleteCharacters(chars);
}
}
@Override
public void deleteElementStart(String type, Attributes attrs) {
flushAnnotations();
target.deleteElementStart(type, attrs);
}
@Override
public void deleteElementEnd() {
flushAnnotations();
target.deleteElementEnd();
}
@Override
public void replaceAttributes(Attributes oldAttrs, Attributes newAttrs) {
flushAnnotations();
target.replaceAttributes(oldAttrs, newAttrs);
}
@Override
public void updateAttributes(AttributesUpdate attrUpdate) {
flushAnnotations();
target.updateAttributes(attrUpdate);
}
@Override
public void annotationBoundary(AnnotationBoundaryMap map) {
int changeSize = map.changeSize();
for (int i = 0; i < changeSize; ++i) {
startAnnotation(map.getChangeKey(i), map.getOldValue(i), map.getNewValue(i));
}
int endSize = map.endSize();
for (int i = 0; i < endSize; ++i) {
endAnnotation(map.getEndKey(i));
}
}
public void startAnnotation(String key, String oldValue, String newValue) {
annotationChanges.put(key, new AnnotationChangeValues(oldValue, newValue));
}
public void endAnnotation(String key) {
annotationChanges.put(key, null);
}
private void flushAnnotations() {
final List<AnnotationChange> changes = new ArrayList<AnnotationChange>();
final List<String> ends = new ArrayList<String>();
for (Map.Entry<String, AnnotationChangeValues> change : annotationChanges.entrySet()) {
String key = change.getKey();
AnnotationChangeValues values = change.getValue();
AnnotationChangeValues previousValues = annotationTracker.get(key);
if (values == null) {
if (previousValues != null) {
annotationTracker.remove(key);
ends.add(key);
}
} else {
if (previousValues == null
|| !ValueUtils.equal(values.oldValue, previousValues.oldValue)
|| !ValueUtils.equal(values.newValue, previousValues.newValue)) {
annotationTracker.put(key, values);
changes.add(new AnnotationChange(key, values.oldValue, values.newValue));
}
}
}
if (!changes.isEmpty() || !ends.isEmpty()) {
target.annotationBoundary(new AnnotationBoundaryMap() {
@Override
public int changeSize() {
return changes.size();
}
@Override
public String getChangeKey(int changeIndex) {
return changes.get(changeIndex).key;
}
@Override
public String getOldValue(int changeIndex) {
return changes.get(changeIndex).oldValue;
}
@Override
public String getNewValue(int changeIndex) {
return changes.get(changeIndex).newValue;
}
@Override
public int endSize() {
return ends.size();
}
@Override
public String getEndKey(int endIndex) {
return ends.get(endIndex);
}
});
}
annotationChanges.clear();
}
}