java/com/android/dialer/preferredsim/impl/PreferredSimFallbackProvider.java

/*
 * 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 com.android.dialer.preferredsim.impl;

import android.Manifest.permission;
import android.content.ContentProvider;
import android.content.ContentValues;
import android.content.pm.PackageManager;
import android.database.Cursor;
import android.net.Uri;
import android.support.annotation.NonNull;
import android.support.annotation.Nullable;
import android.text.TextUtils;
import com.android.dialer.preferredsim.PreferredSimFallbackContract;
import com.android.dialer.preferredsim.PreferredSimFallbackContract.PreferredSim;

/**
 * Content provider for preferred SIM columns that is only available in ContactsProvider after P.
 * Only supports {@link PreferredSimFallbackContract#CONTENT_URI} without id. Insert and delete not
 * supported because there are no current use case.
 *
 * @see PreferredSimFallbackContract
 */
public class PreferredSimFallbackProvider extends ContentProvider {

  private static final String UPDATE_ID_SELECTION = PreferredSim.DATA_ID + " = ?";

  private PreferredSimDatabaseHelper databaseHelper;

  @Override
  public boolean onCreate() {
    databaseHelper = new PreferredSimDatabaseHelper(getContext());
    return true;
  }

  @Nullable
  @Override
  public Cursor query(
      @NonNull Uri uri,
      @Nullable String[] projection,
      @Nullable String selection,
      @Nullable String[] selectionArgs,
      @Nullable String sortOrder) {
    checkReadContactsPermission();
    return databaseHelper
        .getReadableDatabase()
        .query(
            PreferredSimDatabaseHelper.TABLE,
            projection,
            selection,
            selectionArgs,
            null,
            null,
            sortOrder);
  }

  @Nullable
  @Override
  public String getType(@NonNull Uri uri) {
    return null;
  }

  @Nullable
  @Override
  public Uri insert(@NonNull Uri uri, @Nullable ContentValues values) {
    throw new IllegalArgumentException("Unsupported operation");
  }

  /**
   * A row should only be deleted through {@link android.provider.ContactsContract.Data}. Since
   * {@link android.provider.ContactsContract.Data#_ID} is AUTOINCREMENT and could not be reused,
   * rows in this database will simply be orphaned and not cleaned up. To unset preference, update
   * {@link PreferredSim#PREFERRED_PHONE_ACCOUNT_COMPONENT_NAME} and {@link
   * PreferredSim#PREFERRED_PHONE_ACCOUNT_ID} to {@code null}. Delete is only allowed from dialer so
   * simulator can wipe all preference.
   */
  @Override
  public int delete(
      @NonNull Uri uri, @Nullable String selection, @Nullable String[] selectionArgs) {
    if (!TextUtils.equals(getContext().getPackageName(), getCallingPackage())) {
      throw new IllegalArgumentException("Unsupported operation");
    }

    return databaseHelper
        .getWritableDatabase()
        .delete(PreferredSimDatabaseHelper.TABLE, selection, selectionArgs);
  }

  /**
   * Data will be inserted if {@link PreferredSim#DATA_ID} does not already exist in the database.
   * During update the whole row will be replaced.
   *
   * @param uri must be {@link PreferredSimFallbackContract#CONTENT_URI}
   * @param values must contains exactly the keys {@link
   *     PreferredSim#PREFERRED_PHONE_ACCOUNT_COMPONENT_NAME} {@link
   *     PreferredSim#PREFERRED_PHONE_ACCOUNT_ID}. The value may be {@code null}
   * @param selection must equals "data_id = ?"
   * @param selectionArgs must contains exactly the {@link PreferredSim#DATA_ID}
   */
  @Override
  public int update(
      @NonNull Uri uri,
      @Nullable ContentValues values,
      @Nullable String selection,
      @Nullable String[] selectionArgs) {
    checkWriteContactsPermission();
    if (values == null) {
      return 0;
    }
    if (!UPDATE_ID_SELECTION.equals(selection)
        || selectionArgs == null
        || selectionArgs.length != 1) {
      throw new IllegalArgumentException("Unsupported operation");
    }
    values.put(PreferredSim.DATA_ID, selectionArgs[0]);
    if (databaseHelper.getWritableDatabase().replace(PreferredSimDatabaseHelper.TABLE, null, values)
        == -1) {
      throw new IllegalStateException("update failed");
    }
    return 1;
  }

  private void checkReadContactsPermission() {
    if (getContext().checkCallingOrSelfPermission(permission.READ_CONTACTS)
        == PackageManager.PERMISSION_DENIED) {
      throw new SecurityException("READ_CONTACTS required");
    }
  }

  private void checkWriteContactsPermission() {
    if (getContext().checkCallingOrSelfPermission(permission.WRITE_CONTACTS)
        == PackageManager.PERMISSION_DENIED) {
      throw new SecurityException("WRITE_CONTACTS required");
    }
  }
}