CSAI: add TvAdServiceInfo

/*

 * Copyright 2023 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.media.tv.ad;

parcelable TvAdServiceInfo;

/*

 * Copyright (C) 2023 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.media.tv.ad;

import android.annotation.Nullable;

import android.content.ComponentName;

import android.content.Context;

import android.content.Intent;

import android.content.pm.PackageManager;

import android.content.pm.ResolveInfo;

import android.content.pm.ServiceInfo;

import android.content.res.Resources;

import android.content.res.XmlResourceParser;

import android.os.Parcel;

import android.os.Parcelable;

import android.util.AttributeSet;

import android.util.Xml;

import androidx.annotation.NonNull;

import org.xmlpull.v1.XmlPullParser;

import org.xmlpull.v1.XmlPullParserException;

import java.io.IOException;

import java.util.ArrayList;

import java.util.List;

/**

 * This class is used to specify meta information of a TV AD service.

 * @hide

 */

public final class TvAdServiceInfo implements Parcelable {

    private static final boolean DEBUG = false;

    private static final String TAG = "TvAdServiceInfo";

    private static final String XML_START_TAG_NAME = "tv-ad-service";

    private final ResolveInfo mService;

    private final String mId;

    private final List<String> mTypes = new ArrayList<>();

    /**

     * Constructs a TvAdServiceInfo object.

     *

     * @param context the application context

     * @param component the component name of the TvAdService

     */

    public TvAdServiceInfo(@NonNull Context context, @NonNull ComponentName component) {

        if (context == null) {

            throw new IllegalArgumentException("context cannot be null.");

        }

        // TODO: use a constant

        Intent intent = new Intent("android.media.tv.ad.TvAdService").setComponent(component);

        ResolveInfo resolveInfo = context.getPackageManager().resolveService(

                intent, PackageManager.GET_SERVICES | PackageManager.GET_META_DATA);

        if (resolveInfo == null) {

            throw new IllegalArgumentException("Invalid component. Can't find the service.");

        }

        ComponentName componentName = new ComponentName(resolveInfo.serviceInfo.packageName,

                resolveInfo.serviceInfo.name);

        String id;

        id = generateAdServiceId(componentName);

        List<String> types = new ArrayList<>();

        parseServiceMetadata(resolveInfo, context, types);

        mService = resolveInfo;

        mId = id;

    }

    private TvAdServiceInfo(ResolveInfo service, String id, List<String> types) {

        mService = service;

        mId = id;

        mTypes.addAll(types);

    }

    private TvAdServiceInfo(@NonNull Parcel in) {

        mService = ResolveInfo.CREATOR.createFromParcel(in);

        mId = in.readString();

        in.readStringList(mTypes);

    }

    public static final Creator<TvAdServiceInfo> CREATOR = new Creator<TvAdServiceInfo>() {

        @Override

        public TvAdServiceInfo createFromParcel(Parcel in) {

            return new TvAdServiceInfo(in);

        }

        @Override

        public TvAdServiceInfo[] newArray(int size) {

            return new TvAdServiceInfo[size];

        }

    };

    /**

     * Returns a unique ID for this TV AD service. The ID is generated from the package and class

     * name implementing the TV AD service.

     */

    @NonNull

    public String getId() {

        return mId;

    }

    /**

     * Returns the component of the TV AD service.

     * @hide

     */

    public ComponentName getComponent() {

        return new ComponentName(mService.serviceInfo.packageName, mService.serviceInfo.name);

    }

    /**

     * Returns the information of the service that implements this AD service.

     */

    @Nullable

    public ServiceInfo getServiceInfo() {

        return mService.serviceInfo;

    }

    /**

     * Gets supported TV AD types.

     */

    @NonNull

    public List<String> getSupportedTypes() {

        return mTypes;

    }

    private static String generateAdServiceId(ComponentName name) {

        return name.flattenToShortString();

    }

    private static void parseServiceMetadata(

            ResolveInfo resolveInfo, Context context, List<String> types) {

        ServiceInfo serviceInfo = resolveInfo.serviceInfo;

        PackageManager pm = context.getPackageManager();

        // TODO: use constant for the metadata

        try (XmlResourceParser parser =

                     serviceInfo.loadXmlMetaData(pm, "android.media.tv.ad.service")) {

            if (parser == null) {

                throw new IllegalStateException(

                        "No " + "android.media.tv.ad.service"

                                + " meta-data found for " + serviceInfo.name);

            }

            Resources resources = pm.getResourcesForApplication(serviceInfo.applicationInfo);

            AttributeSet attrs = Xml.asAttributeSet(parser);

            int type;

            while ((type = parser.next()) != XmlPullParser.END_DOCUMENT

                    && type != XmlPullParser.START_TAG) {

                // move to the START_TAG

            }

            String nodeName = parser.getName();

            if (!XML_START_TAG_NAME.equals(nodeName)) {

                throw new IllegalStateException("Meta-data does not start with "

                        + XML_START_TAG_NAME + " tag for " + serviceInfo.name);

            }

            // TODO: parse attributes

        } catch (IOException | XmlPullParserException e) {

            throw new IllegalStateException(

                    "Failed reading meta-data for " + serviceInfo.packageName, e);

        } catch (PackageManager.NameNotFoundException e) {

            throw new IllegalStateException("No resources found for " + serviceInfo.packageName, e);

        }

    }

    @Override

    public int describeContents() {

        return 0;

    }

    @Override

    public void writeToParcel(@NonNull Parcel dest, int flags) {

        mService.writeToParcel(dest, flags);

        dest.writeString(mId);

        dest.writeStringList(mTypes);

    }

}