app_Settings/src/com/android/settings/bluetooth/BluetoothFindBroadcastsFragment.java

/*
 * Copyright (C) 2022 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.settings.bluetooth;

import static android.bluetooth.BluetoothDevice.BOND_NONE;
import static android.os.UserManager.DISALLOW_CONFIG_BLUETOOTH;

import android.app.AlertDialog;
import android.app.settings.SettingsEnums;
import android.bluetooth.BluetoothDevice;
import android.bluetooth.BluetoothLeBroadcastAssistant;
import android.bluetooth.BluetoothLeBroadcastMetadata;
import android.bluetooth.BluetoothLeBroadcastReceiveState;
import android.bluetooth.le.ScanFilter;
import android.content.Context;
import android.os.Bundle;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.WindowManager;
import android.widget.EditText;
import android.widget.TextView;

import androidx.annotation.NonNull;
import androidx.annotation.VisibleForTesting;
import androidx.preference.Preference;
import androidx.preference.PreferenceCategory;

import com.android.settings.R;
import com.android.settings.dashboard.RestrictedDashboardFragment;
import com.android.settingslib.bluetooth.CachedBluetoothDevice;
import com.android.settingslib.bluetooth.LocalBluetoothLeBroadcastAssistant;
import com.android.settingslib.bluetooth.LocalBluetoothManager;
import com.android.settingslib.bluetooth.LocalBluetoothProfileManager;
import com.android.settingslib.core.AbstractPreferenceController;
import com.android.settingslib.core.lifecycle.Lifecycle;

import java.nio.charset.StandardCharsets;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import java.util.concurrent.Executor;
import java.util.concurrent.Executors;


/**
 * This fragment allowed users to find the nearby broadcast sources.
 */
public class BluetoothFindBroadcastsFragment extends RestrictedDashboardFragment {

    private static final String TAG = "BtFindBroadcastsFrg";

    public static final String KEY_DEVICE_ADDRESS = "device_address";
    public static final String PREF_KEY_BROADCAST_SOURCE_LIST = "broadcast_source_list";

    @VisibleForTesting
    String mDeviceAddress;
    @VisibleForTesting
    LocalBluetoothManager mManager;
    @VisibleForTesting
    CachedBluetoothDevice mCachedDevice;
    @VisibleForTesting
    PreferenceCategory mBroadcastSourceListCategory;
    BluetoothFindBroadcastsHeaderController mBluetoothFindBroadcastsHeaderController;
    private LocalBluetoothLeBroadcastAssistant mLeBroadcastAssistant;
    private BluetoothBroadcastSourcePreference mSelectedPreference;
    private Executor mExecutor;
    private int mSourceId;

    private BluetoothLeBroadcastAssistant.Callback mBroadcastAssistantCallback =
            new BluetoothLeBroadcastAssistant.Callback() {
                @Override
                public void onSearchStarted(int reason) {
                    Log.d(TAG, "onSearchStarted: " + reason);

                    getActivity().runOnUiThread(
                            () -> cacheRemoveAllPrefs(mBroadcastSourceListCategory));
                }

                @Override
                public void onSearchStartFailed(int reason) {
                    Log.d(TAG, "onSearchStartFailed: " + reason);
                }

                @Override
                public void onSearchStopped(int reason) {
                    Log.d(TAG, "onSearchStopped: " + reason);
                }

                @Override
                public void onSearchStopFailed(int reason) {
                    Log.d(TAG, "onSearchStopFailed: " + reason);
                }

                @Override
                public void onSourceFound(@NonNull BluetoothLeBroadcastMetadata source) {
                    Log.d(TAG, "onSourceFound:");
                    getActivity().runOnUiThread(() -> updateListCategory(source, false));
                }

                @Override
                public void onSourceAdded(@NonNull BluetoothDevice sink, int sourceId, int reason) {
                    setSourceId(sourceId);
                    if (mSelectedPreference == null) {
                        Log.w(TAG, "onSourceAdded: mSelectedPreference == null!");
                        return;
                    }
                    getActivity().runOnUiThread(() -> updateListCategory(
                            mSelectedPreference.getBluetoothLeBroadcastMetadata(), true));
                }

                @Override
                public void onSourceAddFailed(@NonNull BluetoothDevice sink,
                        @NonNull BluetoothLeBroadcastMetadata source, int reason) {
                    mSelectedPreference = null;
                    Log.d(TAG, "onSourceAddFailed: clear the mSelectedPreference.");
                }

                @Override
                public void onSourceModified(@NonNull BluetoothDevice sink, int sourceId,
                        int reason) {
                }

                @Override
                public void onSourceModifyFailed(@NonNull BluetoothDevice sink, int sourceId,
                        int reason) {
                }

                @Override
                public void onSourceRemoved(@NonNull BluetoothDevice sink, int sourceId,
                        int reason) {
                    Log.d(TAG, "onSourceRemoved:");
                }

                @Override
                public void onSourceRemoveFailed(@NonNull BluetoothDevice sink, int sourceId,
                        int reason) {
                    Log.d(TAG, "onSourceRemoveFailed:");
                }

                @Override
                public void onReceiveStateChanged(@NonNull BluetoothDevice sink, int sourceId,
                        @NonNull BluetoothLeBroadcastReceiveState state) {
                    Log.d(TAG, "onReceiveStateChanged:");
                }
            };

    public BluetoothFindBroadcastsFragment() {
        super(DISALLOW_CONFIG_BLUETOOTH);
    }

    @VisibleForTesting
    LocalBluetoothManager getLocalBluetoothManager(Context context) {
        return Utils.getLocalBtManager(context);
    }

    @VisibleForTesting
    CachedBluetoothDevice getCachedDevice(String deviceAddress) {
        BluetoothDevice remoteDevice =
                mManager.getBluetoothAdapter().getRemoteDevice(deviceAddress);
        return mManager.getCachedDeviceManager().findDevice(remoteDevice);
    }

    @Override
    public void onAttach(Context context) {
        mDeviceAddress = getArguments().getString(KEY_DEVICE_ADDRESS);
        mManager = getLocalBluetoothManager(context);
        mCachedDevice = getCachedDevice(mDeviceAddress);
        mLeBroadcastAssistant = getLeBroadcastAssistant();
        mExecutor = Executors.newSingleThreadExecutor();

        super.onAttach(context);
        if (mCachedDevice == null || mLeBroadcastAssistant == null) {
            //Close this page if device is null with invalid device mac address
            //or if the device does not have LeBroadcastAssistant profile
            Log.w(TAG, "onAttach() CachedDevice or LeBroadcastAssistant is null!");
            finish();
            return;
        }
    }

    @Override
    public void onCreate(Bundle icicle) {
        super.onCreate(icicle);

        mBroadcastSourceListCategory = findPreference(PREF_KEY_BROADCAST_SOURCE_LIST);
    }

    @Override
    public void onStart() {
        super.onStart();
        if (mLeBroadcastAssistant != null) {
            mLeBroadcastAssistant.registerServiceCallBack(mExecutor, mBroadcastAssistantCallback);
        }
    }

    @Override
    public void onResume() {
        super.onResume();
        finishFragmentIfNecessary();
        //check assistant status. Start searching...
        if (mLeBroadcastAssistant != null && !mLeBroadcastAssistant.isSearchInProgress()) {
            mLeBroadcastAssistant.startSearchingForSources(getScanFilter());
        }
    }

    @Override
    public void onStop() {
        super.onStop();
        if (mLeBroadcastAssistant != null) {
            mLeBroadcastAssistant.unregisterServiceCallBack(mBroadcastAssistantCallback);
        }
    }

    @VisibleForTesting
    void finishFragmentIfNecessary() {
        if (mCachedDevice.getBondState() == BOND_NONE) {
            finish();
            return;
        }
    }

    @Override
    public int getMetricsCategory() {
        //TODO(b/228255796) : add new enum for find broadcast fragment
        return SettingsEnums.PAGE_UNKNOWN;
    }

    /**
     * Starts to scan broadcast source by the BluetoothLeBroadcastAssistant.
     */
    public void scanBroadcastSource() {
        if (mLeBroadcastAssistant == null) {
            Log.w(TAG, "scanBroadcastSource: LeBroadcastAssistant is null!");
            return;
        }
        mLeBroadcastAssistant.startSearchingForSources(getScanFilter());
    }

    /**
     * Leaves the broadcast source by the BluetoothLeBroadcastAssistant.
     */
    public void leaveBroadcastSession() {
        if (mLeBroadcastAssistant == null || mCachedDevice == null) {
            Log.w(TAG, "leaveBroadcastSession: LeBroadcastAssistant or CachedDevice is null!");
            return;
        }
        mLeBroadcastAssistant.removeSource(mCachedDevice.getDevice(), getSourceId());
    }

    @Override
    protected String getLogTag() {
        return TAG;
    }

    @Override
    protected int getPreferenceScreenResId() {
        return R.xml.bluetooth_find_broadcasts_fragment;
    }

    @Override
    protected List<AbstractPreferenceController> createPreferenceControllers(Context context) {
        ArrayList<AbstractPreferenceController> controllers = new ArrayList<>();

        if (mCachedDevice != null) {
            Lifecycle lifecycle = getSettingsLifecycle();
            mBluetoothFindBroadcastsHeaderController = new BluetoothFindBroadcastsHeaderController(
                    context, this, mCachedDevice, lifecycle, mManager);
            controllers.add(mBluetoothFindBroadcastsHeaderController);
        }
        return controllers;
    }

    /**
     * Gets the LocalBluetoothLeBroadcastAssistant
     * @return the LocalBluetoothLeBroadcastAssistant
     */
    public LocalBluetoothLeBroadcastAssistant getLeBroadcastAssistant() {
        if (mManager == null) {
            Log.w(TAG, "getLeBroadcastAssistant: LocalBluetoothManager is null!");
            return null;
        }

        LocalBluetoothProfileManager profileManager = mManager.getProfileManager();
        if (profileManager == null) {
            Log.w(TAG, "getLeBroadcastAssistant: LocalBluetoothProfileManager is null!");
            return null;
        }

        return profileManager.getLeAudioBroadcastAssistantProfile();
    }

    private List<ScanFilter> getScanFilter() {
        // Currently there is no function for setting the ScanFilter. It may have this function
        // in the further.
        return Collections.emptyList();
    }

    private void updateListCategory(BluetoothLeBroadcastMetadata source, boolean isConnected) {
        BluetoothBroadcastSourcePreference item = mBroadcastSourceListCategory.findPreference(
                Integer.toString(source.getBroadcastId()));
        if (item == null) {
            item = createBluetoothBroadcastSourcePreference(source);
            mBroadcastSourceListCategory.addPreference(item);
        }
        item.updateMetadataAndRefreshUi(source, isConnected);
        item.setOrder(isConnected ? 0 : 1);

        //refresh the header
        if (mBluetoothFindBroadcastsHeaderController != null) {
            mBluetoothFindBroadcastsHeaderController.refreshUi();
        }
    }

    private BluetoothBroadcastSourcePreference createBluetoothBroadcastSourcePreference(
            BluetoothLeBroadcastMetadata source) {
        BluetoothBroadcastSourcePreference pref = new BluetoothBroadcastSourcePreference(
                getContext(), source);
        pref.setKey(Integer.toString(source.getBroadcastId()));
        pref.setOnPreferenceClickListener(preference -> {
            if (source.isEncrypted()) {
                launchBroadcastCodeDialog(pref);
            } else {
                addSource(pref);
            }
            return true;
        });
        return pref;
    }

    private void addSource(BluetoothBroadcastSourcePreference pref) {
        if (mLeBroadcastAssistant == null || mCachedDevice == null) {
            Log.w(TAG, "addSource: LeBroadcastAssistant or CachedDevice is null!");
            return;
        }
        if (mSelectedPreference != null) {
            // The previous preference status set false after user selects the new Preference.
            getActivity().runOnUiThread(
                    () -> {
                        mSelectedPreference.updateMetadataAndRefreshUi(
                                mSelectedPreference.getBluetoothLeBroadcastMetadata(), false);
                        mSelectedPreference.setOrder(1);
                    });
        }
        mSelectedPreference = pref;
        mLeBroadcastAssistant.addSource(mCachedDevice.getDevice(),
                pref.getBluetoothLeBroadcastMetadata(), true);
    }

    private void addBroadcastCodeIntoPreference(BluetoothBroadcastSourcePreference pref,
            String broadcastCode) {
        BluetoothLeBroadcastMetadata metadata =
                new BluetoothLeBroadcastMetadata.Builder(pref.getBluetoothLeBroadcastMetadata())
                        .setBroadcastCode(broadcastCode.getBytes(StandardCharsets.UTF_8))
                        .build();
        pref.updateMetadataAndRefreshUi(metadata, false);
    }

    private void launchBroadcastCodeDialog(BluetoothBroadcastSourcePreference pref) {
        final View layout = LayoutInflater.from(getContext()).inflate(
                R.layout.bluetooth_find_broadcast_password_dialog, null);
        final TextView broadcastName = layout.requireViewById(R.id.broadcast_name_text);
        final EditText editText = layout.requireViewById(R.id.broadcast_edit_text);
        broadcastName.setText(pref.getTitle());
        AlertDialog alertDialog = new AlertDialog.Builder(getContext())
                .setTitle(R.string.find_broadcast_password_dialog_title)
                .setView(layout)
                .setNeutralButton(android.R.string.cancel, null)
                .setPositiveButton(R.string.bluetooth_connect_access_dialog_positive,
                        (d, w) -> {
                            Log.d(TAG, "setPositiveButton: clicked");
                            addBroadcastCodeIntoPreference(pref, editText.getText().toString());
                            addSource(pref);
                        })
                .create();

        alertDialog.getWindow().setType(WindowManager.LayoutParams.TYPE_KEYGUARD_DIALOG);
        alertDialog.show();
    }

    public int getSourceId() {
        return mSourceId;
    }

    public void setSourceId(int sourceId) {
        mSourceId = sourceId;
    }
}