/*
 * Copyright (C) 2018 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.fuelgauge;

import android.app.AppOpsManager;
import android.content.Context;
import android.support.annotation.VisibleForTesting;
import android.support.v7.preference.Preference;

import com.android.internal.util.CollectionUtils;
import com.android.settings.R;
import com.android.settings.SettingsActivity;
import com.android.settings.core.BasePreferenceController;
import com.android.settings.core.InstrumentedPreferenceFragment;
import com.android.settings.fuelgauge.batterytip.AppInfo;

import java.util.ArrayList;
import java.util.List;

/**
 * Controller to change and update the smart battery toggle
 */
public class RestrictAppPreferenceController extends BasePreferenceController {
    @VisibleForTesting
    static final String KEY_RESTRICT_APP = "restricted_app";

    private AppOpsManager mAppOpsManager;
    private List<AppInfo> mAppInfos;
    private SettingsActivity mSettingsActivity;
    private InstrumentedPreferenceFragment mPreferenceFragment;

    public RestrictAppPreferenceController(Context context) {
        super(context, KEY_RESTRICT_APP);
        mAppOpsManager = (AppOpsManager) context.getSystemService(Context.APP_OPS_SERVICE);
    }

    public RestrictAppPreferenceController(SettingsActivity settingsActivity,
            InstrumentedPreferenceFragment preferenceFragment) {
        this(settingsActivity.getApplicationContext());
        mSettingsActivity = settingsActivity;
        mPreferenceFragment = preferenceFragment;
    }

    @Override
    public int getAvailabilityStatus() {
        return AVAILABLE;
    }

    @Override
    public void updateState(Preference preference) {
        super.updateState(preference);

        final List<AppOpsManager.PackageOps> packageOpsList = mAppOpsManager.getPackagesForOps(
                new int[]{AppOpsManager.OP_RUN_ANY_IN_BACKGROUND});
        mAppInfos = new ArrayList<>();

        for (int i = 0, size = CollectionUtils.size(packageOpsList); i < size; i++) {
            final AppOpsManager.PackageOps packageOps = packageOpsList.get(i);
            final List<AppOpsManager.OpEntry> entries = packageOps.getOps();
            for (int j = 0; j < entries.size(); j++) {
                AppOpsManager.OpEntry ent = entries.get(j);
                if (ent.getOp() != AppOpsManager.OP_RUN_ANY_IN_BACKGROUND) {
                    continue;
                }
                if (ent.getMode() != AppOpsManager.MODE_ALLOWED) {
                    mAppInfos.add(new AppInfo.Builder()
                            .setPackageName(packageOps.getPackageName())
                            .setUid(packageOps.getUid())
                            .build());
                }
            }
        }

        final int num = mAppInfos.size();
        // Enable the preference if some apps already been restricted, otherwise disable it
        preference.setEnabled(num > 0);
        preference.setSummary(
                mContext.getResources().getQuantityString(R.plurals.restricted_app_summary, num,
                        num));
    }

    @Override
    public boolean handlePreferenceTreeClick(Preference preference) {
        if (getPreferenceKey().equals(preference.getKey())) {
            // start fragment
            RestrictedAppDetails.startRestrictedAppDetails(mSettingsActivity, mPreferenceFragment,
                    mAppInfos);
            return true;
        }

        return super.handlePreferenceTreeClick(preference);
    }
}