/*
* Copyright (C) 2017 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 android.service.autofill;
import static android.view.autofill.Helper.sDebug;
import android.annotation.DrawableRes;
import android.annotation.NonNull;
import android.annotation.Nullable;
import android.annotation.TestApi;
import android.os.Parcel;
import android.os.Parcelable;
import android.text.TextUtils;
import android.util.Log;
import android.view.autofill.AutofillId;
import android.widget.ImageView;
import android.widget.RemoteViews;
import com.android.internal.util.Preconditions;
import java.util.ArrayList;
import java.util.regex.Pattern;
/**
* Replaces the content of a child {@link ImageView} of a
* {@link RemoteViews presentation template} with the first image that matches a regular expression
* (regex).
*
* Typically used to display credit card logos. Example:
*
*
* new ImageTransformation.Builder(ccNumberId, Pattern.compile("^4815.*$"),
* R.drawable.ic_credit_card_logo1, "Brand 1")
* .addOption(Pattern.compile("^1623.*$"), R.drawable.ic_credit_card_logo2, "Brand 2")
* .addOption(Pattern.compile("^42.*$"), R.drawable.ic_credit_card_logo3, "Brand 3")
* .build();
*
*
* There is no imposed limit in the number of options, but keep in mind that regexs are
* expensive to evaluate, so use the minimum number of regexs and add the most common first
* (for example, if this is a tranformation for a credit card logo and the most common credit card
* issuers are banks X and Y, add the regexes that resolves these 2 banks first).
*/
public final class ImageTransformation extends InternalTransformation implements Transformation,
Parcelable {
private static final String TAG = "ImageTransformation";
private final AutofillId mId;
private final ArrayList mOptions;
private ImageTransformation(Builder builder) {
mId = builder.mId;
mOptions = builder.mOptions;
}
/** @hide */
@TestApi
@Override
public void apply(@NonNull ValueFinder finder, @NonNull RemoteViews parentTemplate,
int childViewId) throws Exception {
final String value = finder.findByAutofillId(mId);
if (value == null) {
Log.w(TAG, "No view for id " + mId);
return;
}
final int size = mOptions.size();
if (sDebug) {
Log.d(TAG, size + " multiple options on id " + childViewId + " to compare against");
}
for (int i = 0; i < size; i++) {
final Option option = mOptions.get(i);
try {
if (option.pattern.matcher(value).matches()) {
Log.d(TAG, "Found match at " + i + ": " + option);
parentTemplate.setImageViewResource(childViewId, option.resId);
if (option.contentDescription != null) {
parentTemplate.setContentDescription(childViewId,
option.contentDescription);
}
return;
}
} catch (Exception e) {
// Do not log full exception to avoid PII leaking
Log.w(TAG, "Error matching regex #" + i + "(" + option.pattern + ") on id "
+ option.resId + ": " + e.getClass());
throw e;
}
}
if (sDebug) Log.d(TAG, "No match for " + value);
}
/**
* Builder for {@link ImageTransformation} objects.
*/
public static class Builder {
private final AutofillId mId;
private final ArrayList mOptions = new ArrayList<>();
private boolean mDestroyed;
/**
* Creates a new builder for a autofill id and add a first option.
*
* @param id id of the screen field that will be used to evaluate whether the image should
* be used.
* @param regex regular expression defining what should be matched to use this image.
* @param resId resource id of the image (in the autofill service's package). The
* {@link RemoteViews presentation} must contain a {@link ImageView} child with that id.
*
* @deprecated use
* {@link #ImageTransformation.Builder(AutofillId, Pattern, int, CharSequence)} instead.
*/
@Deprecated
public Builder(@NonNull AutofillId id, @NonNull Pattern regex, @DrawableRes int resId) {
mId = Preconditions.checkNotNull(id);
addOption(regex, resId);
}
/**
* Creates a new builder for a autofill id and add a first option.
*
* @param id id of the screen field that will be used to evaluate whether the image should
* be used.
* @param regex regular expression defining what should be matched to use this image.
* @param resId resource id of the image (in the autofill service's package). The
* {@link RemoteViews presentation} must contain a {@link ImageView} child with that id.
* @param contentDescription content description to be applied in the child view.
*/
public Builder(@NonNull AutofillId id, @NonNull Pattern regex, @DrawableRes int resId,
@NonNull CharSequence contentDescription) {
mId = Preconditions.checkNotNull(id);
addOption(regex, resId, contentDescription);
}
/**
* Adds an option to replace the child view with a different image when the regex matches.
*
* @param regex regular expression defining what should be matched to use this image.
* @param resId resource id of the image (in the autofill service's package). The
* {@link RemoteViews presentation} must contain a {@link ImageView} child with that id.
*
* @return this build
*
* @deprecated use {@link #addOption(Pattern, int, CharSequence)} instead.
*/
@Deprecated
public Builder addOption(@NonNull Pattern regex, @DrawableRes int resId) {
addOptionInternal(regex, resId, null);
return this;
}
/**
* Adds an option to replace the child view with a different image and content description
* when the regex matches.
*
* @param regex regular expression defining what should be matched to use this image.
* @param resId resource id of the image (in the autofill service's package). The
* {@link RemoteViews presentation} must contain a {@link ImageView} child with that id.
* @param contentDescription content description to be applied in the child view.
*
* @return this build
*/
public Builder addOption(@NonNull Pattern regex, @DrawableRes int resId,
@NonNull CharSequence contentDescription) {
addOptionInternal(regex, resId, Preconditions.checkNotNull(contentDescription));
return this;
}
private void addOptionInternal(@NonNull Pattern regex, @DrawableRes int resId,
@Nullable CharSequence contentDescription) {
throwIfDestroyed();
Preconditions.checkNotNull(regex);
Preconditions.checkArgument(resId != 0);
mOptions.add(new Option(regex, resId, contentDescription));
}
/**
* Creates a new {@link ImageTransformation} instance.
*/
public ImageTransformation build() {
throwIfDestroyed();
mDestroyed = true;
return new ImageTransformation(this);
}
private void throwIfDestroyed() {
Preconditions.checkState(!mDestroyed, "Already called build()");
}
}
/////////////////////////////////////
// Object "contract" methods. //
/////////////////////////////////////
@Override
public String toString() {
if (!sDebug) return super.toString();
return "ImageTransformation: [id=" + mId + ", options=" + mOptions + "]";
}
/////////////////////////////////////
// Parcelable "contract" methods. //
/////////////////////////////////////
@Override
public int describeContents() {
return 0;
}
@Override
public void writeToParcel(Parcel parcel, int flags) {
parcel.writeParcelable(mId, flags);
final int size = mOptions.size();
final Pattern[] patterns = new Pattern[size];
final int[] resIds = new int[size];
final CharSequence[] contentDescriptions = new String[size];
for (int i = 0; i < size; i++) {
final Option option = mOptions.get(i);
patterns[i] = option.pattern;
resIds[i] = option.resId;
contentDescriptions[i] = option.contentDescription;
}
parcel.writeSerializable(patterns);
parcel.writeIntArray(resIds);
parcel.writeCharSequenceArray(contentDescriptions);
}
public static final @android.annotation.NonNull Parcelable.Creator CREATOR =
new Parcelable.Creator() {
@Override
public ImageTransformation createFromParcel(Parcel parcel) {
final AutofillId id = parcel.readParcelable(null);
final Pattern[] regexs = (Pattern[]) parcel.readSerializable();
final int[] resIds = parcel.createIntArray();
final CharSequence[] contentDescriptions = parcel.readCharSequenceArray();
// Always go through the builder to ensure the data ingested by the system obeys the
// contract of the builder to avoid attacks using specially crafted parcels.
final CharSequence contentDescription = contentDescriptions[0];
final ImageTransformation.Builder builder = (contentDescription != null)
? new ImageTransformation.Builder(id, regexs[0], resIds[0], contentDescription)
: new ImageTransformation.Builder(id, regexs[0], resIds[0]);
final int size = regexs.length;
for (int i = 1; i < size; i++) {
if (contentDescriptions[i] != null) {
builder.addOption(regexs[i], resIds[i], contentDescriptions[i]);
} else {
builder.addOption(regexs[i], resIds[i]);
}
}
return builder.build();
}
@Override
public ImageTransformation[] newArray(int size) {
return new ImageTransformation[size];
}
};
private static final class Option {
public final Pattern pattern;
public final int resId;
public final CharSequence contentDescription;
Option(Pattern pattern, int resId, CharSequence contentDescription) {
this.pattern = pattern;
this.resId = resId;
this.contentDescription = TextUtils.trimNoCopySpans(contentDescription);
}
}
}
