/**
* 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.wavepanel.impl.reader;
import com.google.common.annotations.VisibleForTesting;
import org.waveprotocol.wave.client.wave.DocumentRegistry;
import org.waveprotocol.wave.client.wave.InteractiveDocument;
import org.waveprotocol.wave.client.wave.LocalSupplementedWave;
import org.waveprotocol.wave.client.wavepanel.impl.focus.FocusFramePresenter;
import org.waveprotocol.wave.client.wavepanel.impl.focus.FocusFramePresenter.FocusOrder;
import org.waveprotocol.wave.client.wavepanel.impl.focus.ViewTraverser;
import org.waveprotocol.wave.client.wavepanel.view.BlipView;
import org.waveprotocol.wave.client.wavepanel.view.dom.ModelAsViewProvider;
import org.waveprotocol.wave.model.conversation.ConversationBlip;
/**
* Inteprets focus-frame movement as reading actions, and also provides an
* ordering for focus frame movement, based on unread content.
*
*/
public final class Reader implements FocusFramePresenter.Listener, FocusOrder {
private final LocalSupplementedWave supplement;
private final ModelAsViewProvider models;
private final ViewTraverser traverser;
private final DocumentRegistry<? extends InteractiveDocument> documents;
@VisibleForTesting
Reader(LocalSupplementedWave supplement, ModelAsViewProvider models,
DocumentRegistry<? extends InteractiveDocument> documents, ViewTraverser traverser) {
this.supplement = supplement;
this.models = models;
this.documents = documents;
this.traverser = traverser;
}
/**
* Builds and installs the reading feature.
*
* @return the feature.
*/
public static Reader install(LocalSupplementedWave supplement, FocusFramePresenter focus,
ModelAsViewProvider models, DocumentRegistry<? extends InteractiveDocument> documents) {
ViewTraverser traverser = new ViewTraverser();
final Reader reader = new Reader(supplement, models, documents, traverser);
focus.setOrder(reader);
focus.addListener(reader);
return reader;
}
@Override
public void onFocusMoved(BlipView oldUi, BlipView newUi) {
if (oldUi != null) {
ConversationBlip oldBlip = models.getBlip(oldUi);
InteractiveDocument document = documents.get(oldBlip);
if (oldBlip != null) {
supplement.stopReading(oldBlip);
document.stopDiffRetention();
document.clearDiffs();
}
}
if (newUi != null) {
// UI hack: normally, becoming read triggers diff clearing, except when
// the cause of becoming read is focus-frame placement.
ConversationBlip newBlip = models.getBlip(newUi);
InteractiveDocument document = documents.get(newBlip);
if (newBlip != null) {
document.startDiffRetention();
supplement.startReading(newBlip);
}
}
}
public boolean isRead(BlipView blipUi) {
return !supplement.isUnread(models.getBlip(blipUi));
}
//
// Next/Previous blips based on read/unread state.
//
@Override
public BlipView getNext(BlipView start) {
BlipView blipUi = traverser.getNext(start);
while (blipUi != null && isRead(blipUi)) {
blipUi = traverser.getNext(blipUi);
}
return blipUi;
}
@Override
public BlipView getPrevious(BlipView start) {
BlipView blipUi = traverser.getPrevious(start);
while (blipUi != null && isRead(blipUi)) {
blipUi = traverser.getPrevious(blipUi);
}
return blipUi;
}
}