/*
* Copyright (C) 2015 The Android Open Source Project
*
* 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 com.android.documentsui;
import static com.android.documentsui.Shared.DEBUG;
import static com.android.documentsui.Shared.MAX_DOCS_IN_INTENT;
import static com.android.documentsui.model.DocumentInfo.getCursorString;
import android.content.ClipData;
import android.content.ClipDescription;
import android.content.ComponentName;
import android.content.Intent;
import android.content.pm.PackageManager;
import android.content.res.Resources;
import android.database.Cursor;
import android.net.Uri;
import android.os.Build;
import android.provider.DocumentsContract;
import android.provider.DocumentsContract.Document;
import android.support.annotation.Nullable;
import android.text.TextUtils;
import android.util.Log;
import android.util.Range;
import com.android.documentsui.dirlist.Model;
import com.android.documentsui.model.DocumentInfo;
import java.util.ArrayList;
import java.util.List;
/**
* Provides support for gather a list of quick-viewable files into a quick view intent.
*/
final class QuickViewIntentBuilder {
private static final String TAG = "QuickViewIntentBuilder";
private final DocumentInfo mDocument;
private final Model mModel;
private final PackageManager mPkgManager;
private final Resources mResources;
public QuickViewIntentBuilder(
PackageManager pkgManager,
Resources resources,
DocumentInfo doc,
Model model) {
mPkgManager = pkgManager;
mResources = resources;
mDocument = doc;
mModel = model;
}
/**
* Builds the intent for quick viewing. Short circuits building if a handler cannot
* be resolved; in this case {@code null} is returned.
*/
@Nullable Intent build() {
if (DEBUG) Log.d(TAG, "Preparing intent for doc:" + mDocument.documentId);
String trustedPkg = getQuickViewPackage();
if (!TextUtils.isEmpty(trustedPkg)) {
Intent intent = new Intent(Intent.ACTION_QUICK_VIEW);
intent.setDataAndType(mDocument.derivedUri, mDocument.mimeType);
intent.setFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION);
intent.setPackage(trustedPkg);
if (hasRegisteredHandler(intent)) {
final ArrayList<Uri> uris = new ArrayList<Uri>();
final int documentLocation = collectViewableUris(uris);
final Range<Integer> range = computeSiblingsRange(uris, documentLocation);
ClipData clipData = null;
ClipData.Item item;
Uri uri;
for (int i = range.getLower(); i <= range.getUpper(); i++) {
uri = uris.get(i);
item = new ClipData.Item(uri);
if (DEBUG) Log.d(TAG, "Including file: " + uri);
if (clipData == null) {
clipData = new ClipData(
"URIs", new String[] { ClipDescription.MIMETYPE_TEXT_URILIST },
item);
} else {
clipData.addItem(item);
}
}
// The documentLocation variable contains an index in "uris". However,
// ClipData contains a slice of "uris", so we need to shift the location
// so it points to the same Uri.
intent.putExtra(Intent.EXTRA_INDEX, documentLocation - range.getLower());
intent.setClipData(clipData);
return intent;
} else {
Log.e(TAG, "Can't resolve trusted quick view package: " + trustedPkg);
}
}
return null;
}
private String getQuickViewPackage() {
String resValue = mResources.getString(R.string.trusted_quick_viewer_package);
if (Build.IS_DEBUGGABLE ) {
// Allow users of debug devices to override default quick viewer
// for the purposes of testing.
return android.os.SystemProperties.get("debug.quick_viewer", resValue);
}
return resValue;
}
private int collectViewableUris(ArrayList<Uri> uris) {
final String[] siblingIds = mModel.getModelIds();
uris.ensureCapacity(siblingIds.length);
int documentLocation = 0;
Cursor cursor;
String mimeType;
String id;
String authority;
Uri uri;
// Cursor's are not guaranteed to be immutable. Hence, traverse it only once.
for (int i = 0; i < siblingIds.length; i++) {
cursor = mModel.getItem(siblingIds[i]);
if (cursor == null) {
if (DEBUG) Log.d(TAG,
"Unable to obtain cursor for sibling document, modelId: "
+ siblingIds[i]);
continue;
}
mimeType = getCursorString(cursor, Document.COLUMN_MIME_TYPE);
if (Document.MIME_TYPE_DIR.equals(mimeType)) {
if (DEBUG) Log.d(TAG,
"Skipping directory, not supported by quick view. modelId: "
+ siblingIds[i]);
continue;
}
id = getCursorString(cursor, Document.COLUMN_DOCUMENT_ID);
authority = getCursorString(cursor, RootCursorWrapper.COLUMN_AUTHORITY);
uri = DocumentsContract.buildDocumentUri(authority, id);
uris.add(uri);
if (id.equals(mDocument.documentId)) {
documentLocation = uris.size() - 1; // Position in "uris", not in the model.
if (DEBUG) Log.d(TAG, "Found starting point for QV. " + documentLocation);
}
}
return documentLocation;
}
private static Range<Integer> computeSiblingsRange(List<Uri> uris, int documentLocation) {
// Restrict number of siblings to avoid hitting the IPC limit.
// TODO: Remove this restriction once ClipData can hold an arbitrary number of
// items.
int firstSibling;
int lastSibling;
if (documentLocation < uris.size() / 2) {
firstSibling = Math.max(0, documentLocation - MAX_DOCS_IN_INTENT / 2);
lastSibling = Math.min(uris.size() - 1, firstSibling + MAX_DOCS_IN_INTENT - 1);
} else {
lastSibling = Math.min(uris.size() - 1, documentLocation + MAX_DOCS_IN_INTENT / 2);
firstSibling = Math.max(0, lastSibling - MAX_DOCS_IN_INTENT + 1);
}
if (DEBUG) Log.d(TAG, "Copmuted siblings from index: " + firstSibling
+ " to: " + lastSibling);
return new Range(firstSibling, lastSibling);
}
private boolean hasRegisteredHandler(Intent intent) {
// Try to resolve the intent. If a matching app isn't installed, it won't resolve.
return intent.resolveActivity(mPkgManager) != null;
}
}