/*
 * Copyright (C) 2016 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.incallui.spam;

import android.annotation.TargetApi;
import android.app.Notification;
import android.app.Notification.Builder;
import android.app.PendingIntent;
import android.content.Context;
import android.content.Intent;
import android.database.Cursor;
import android.database.sqlite.SQLiteException;
import android.graphics.drawable.Icon;
import android.os.Build.VERSION_CODES;
import android.provider.CallLog;
import android.provider.CallLog.Calls;
import android.support.annotation.NonNull;
import android.support.annotation.Nullable;
import android.support.v4.os.BuildCompat;
import android.telecom.DisconnectCause;
import android.telephony.PhoneNumberUtils;
import android.text.TextUtils;
import com.android.contacts.common.compat.PhoneNumberUtilsCompat;
import com.android.dialer.blocking.FilteredNumberCompat;
import com.android.dialer.blocking.FilteredNumbersUtil;
import com.android.dialer.common.Assert;
import com.android.dialer.common.LogUtil;
import com.android.dialer.common.concurrent.DialerExecutor.Worker;
import com.android.dialer.common.concurrent.DialerExecutorFactory;
import com.android.dialer.location.GeoUtil;
import com.android.dialer.logging.ContactLookupResult;
import com.android.dialer.logging.DialerImpression;
import com.android.dialer.logging.Logger;
import com.android.dialer.notification.DialerNotificationManager;
import com.android.dialer.notification.NotificationChannelId;
import com.android.dialer.spam.SpamComponent;
import com.android.dialer.telecom.TelecomUtil;
import com.android.dialer.util.PermissionsUtil;
import com.android.incallui.call.CallList;
import com.android.incallui.call.DialerCall;
import com.android.incallui.call.DialerCall.CallHistoryStatus;
import java.util.Random;

/**
 * Creates notifications after a call ends if the call matched the criteria (incoming, accepted,
 * etc).
 */
public class SpamCallListListener implements CallList.Listener {
  /** Common ID for all spam notifications. */
  static final int NOTIFICATION_ID = 1;
  /** Prefix used to generate a unique tag for each spam notification. */
  static final String NOTIFICATION_TAG_PREFIX = "SpamCall_";
  /**
   * Key used to associate all spam notifications into a single group. Note, unlike other group
   * notifications in Dialer, spam notifications don't have a top level group summary notification.
   * The group is still useful for things like rate limiting on a per group basis.
   */
  private static final String GROUP_KEY = "SpamCallGroup";

  private final Context context;
  private final Random random;
  private final DialerExecutorFactory dialerExecutorFactory;

  public SpamCallListListener(Context context, @NonNull DialerExecutorFactory factory) {
    this(context, new Random(), factory);
  }

  public SpamCallListListener(
      Context context, Random rand, @NonNull DialerExecutorFactory factory) {
    this.context = context;
    this.random = rand;
    this.dialerExecutorFactory = Assert.isNotNull(factory);
  }

  /** Checks if the number is in the call history. */
  @TargetApi(VERSION_CODES.M)
  private static final class NumberInCallHistoryWorker implements Worker<Void, Integer> {

    private final Context appContext;
    private final String number;
    private final String countryIso;

    public NumberInCallHistoryWorker(
        @NonNull Context appContext, String number, String countryIso) {
      this.appContext = Assert.isNotNull(appContext);
      this.number = number;
      this.countryIso = countryIso;
    }

    @Override
    @NonNull
    @CallHistoryStatus
    public Integer doInBackground(@Nullable Void input) throws Throwable {
      String numberToQuery = number;
      String fieldToQuery = Calls.NUMBER;
      String normalizedNumber = PhoneNumberUtils.formatNumberToE164(number, countryIso);

      // If we can normalize the number successfully, look in "normalized_number"
      // field instead. Otherwise, look for number in "number" field.
      if (!TextUtils.isEmpty(normalizedNumber)) {
        numberToQuery = normalizedNumber;
        fieldToQuery = Calls.CACHED_NORMALIZED_NUMBER;
      }

      try (Cursor cursor =
          appContext
              .getContentResolver()
              .query(
                  TelecomUtil.getCallLogUri(appContext),
                  new String[] {CallLog.Calls._ID},
                  fieldToQuery + " = ?",
                  new String[] {numberToQuery},
                  null)) {
        return cursor != null && cursor.getCount() > 0
            ? DialerCall.CALL_HISTORY_STATUS_PRESENT
            : DialerCall.CALL_HISTORY_STATUS_NOT_PRESENT;
      } catch (SQLiteException e) {
        LogUtil.e("NumberInCallHistoryWorker.doInBackground", "query call log error", e);
        return DialerCall.CALL_HISTORY_STATUS_UNKNOWN;
      }
    }
  }

  @Override
  public void onIncomingCall(final DialerCall call) {
    String number = call.getNumber();
    if (TextUtils.isEmpty(number)) {
      return;
    }

    if (!PermissionsUtil.hasCallLogReadPermissions(context)) {
      LogUtil.i(
          "SpamCallListListener.onIncomingCall",
          "call log permission missing, not checking if number is in call history");
      return;
    }

    NumberInCallHistoryWorker historyTask =
        new NumberInCallHistoryWorker(context, number, call.getCountryIso());
    dialerExecutorFactory
        .createNonUiTaskBuilder(historyTask)
        .onSuccess((result) -> call.setCallHistoryStatus(result))
        .build()
        .executeParallel(null);
  }

  @Override
  public void onUpgradeToVideo(DialerCall call) {}

  @Override
  public void onSessionModificationStateChange(DialerCall call) {}

  @Override
  public void onCallListChange(CallList callList) {}

  @Override
  public void onWiFiToLteHandover(DialerCall call) {}

  @Override
  public void onHandoverToWifiFailed(DialerCall call) {}

  @Override
  public void onInternationalCallOnWifi(@NonNull DialerCall call) {}

  @Override
  public void onDisconnect(DialerCall call) {
    if (!shouldShowAfterCallNotification(call)) {
      return;
    }
    String e164Number =
        PhoneNumberUtils.formatNumberToE164(
            call.getNumber(), GeoUtil.getCurrentCountryIso(context));
    if (!FilteredNumbersUtil.canBlockNumber(context, e164Number, call.getNumber())
        || !FilteredNumberCompat.canAttemptBlockOperations(context)) {
      return;
    }
    if (e164Number == null) {
      return;
    }
    showNotification(call);
  }

  /** Posts the intent for displaying the after call spam notification to the user. */
  private void showNotification(DialerCall call) {
    if (call.isSpam()) {
      maybeShowSpamCallNotification(call);
    } else {
      maybeShowNonSpamCallNotification(call);
    }
  }

  /** Determines if the after call notification should be shown for the specified call. */
  private boolean shouldShowAfterCallNotification(DialerCall call) {
    if (!SpamComponent.get(context).spam().isSpamNotificationEnabled()) {
      return false;
    }

    String number = call.getNumber();
    if (TextUtils.isEmpty(number)) {
      return false;
    }

    DialerCall.LogState logState = call.getLogState();
    if (!logState.isIncoming) {
      return false;
    }

    if (logState.duration <= 0) {
      return false;
    }

    if (logState.contactLookupResult != ContactLookupResult.Type.NOT_FOUND
        && logState.contactLookupResult != ContactLookupResult.Type.UNKNOWN_LOOKUP_RESULT_TYPE) {
      return false;
    }

    int callHistoryStatus = call.getCallHistoryStatus();
    if (callHistoryStatus == DialerCall.CALL_HISTORY_STATUS_PRESENT) {
      return false;
    } else if (callHistoryStatus == DialerCall.CALL_HISTORY_STATUS_UNKNOWN) {
      LogUtil.i("SpamCallListListener.shouldShowAfterCallNotification", "history status unknown");
      return false;
    }

    // Check if call disconnected because of either user hanging up
    int disconnectCause = call.getDisconnectCause().getCode();
    if (disconnectCause != DisconnectCause.LOCAL && disconnectCause != DisconnectCause.REMOTE) {
      return false;
    }

    LogUtil.i("SpamCallListListener.shouldShowAfterCallNotification", "returning true");
    return true;
  }

  /**
   * Creates a notification builder with properties common among the two after call notifications.
   */
  private Notification.Builder createAfterCallNotificationBuilder(DialerCall call) {
    Notification.Builder builder =
        new Builder(context)
            .setContentIntent(
                createActivityPendingIntent(call, SpamNotificationActivity.ACTION_SHOW_DIALOG))
            .setCategory(Notification.CATEGORY_STATUS)
            .setPriority(Notification.PRIORITY_DEFAULT)
            .setColor(context.getColor(R.color.dialer_theme_color))
            .setSmallIcon(R.drawable.quantum_ic_call_end_vd_theme_24)
            .setGroup(GROUP_KEY);
    if (BuildCompat.isAtLeastO()) {
      builder.setChannelId(NotificationChannelId.DEFAULT);
    }
    return builder;
  }

  private CharSequence getDisplayNumber(DialerCall call) {
    String formattedNumber =
        PhoneNumberUtils.formatNumber(call.getNumber(), GeoUtil.getCurrentCountryIso(context));
    return PhoneNumberUtilsCompat.createTtsSpannable(formattedNumber);
  }

  /** Display a notification with two actions: "add contact" and "report spam". */
  private void showNonSpamCallNotification(DialerCall call) {
    Notification.Builder notificationBuilder =
        createAfterCallNotificationBuilder(call)
            .setContentText(
                context.getString(R.string.spam_notification_non_spam_call_collapsed_text))
            .setStyle(
                new Notification.BigTextStyle()
                    .bigText(
                        context.getString(R.string.spam_notification_non_spam_call_expanded_text)))
            // Add contact
            .addAction(
                new Notification.Action.Builder(
                        R.drawable.quantum_ic_person_add_vd_theme_24,
                        context.getString(R.string.spam_notification_add_contact_action_text),
                        createActivityPendingIntent(
                            call, SpamNotificationActivity.ACTION_ADD_TO_CONTACTS))
                    .build())
            // Block/report spam
            .addAction(
                new Notification.Action.Builder(
                        R.drawable.quantum_ic_block_vd_theme_24,
                        context.getString(R.string.spam_notification_report_spam_action_text),
                        createBlockReportSpamPendingIntent(call))
                    .build())
            .setContentTitle(
                context.getString(R.string.non_spam_notification_title, getDisplayNumber(call)));
    DialerNotificationManager.notify(
        context, getNotificationTagForCall(call), NOTIFICATION_ID, notificationBuilder.build());
  }

  private boolean shouldThrottleSpamNotification() {
    int randomNumber = random.nextInt(100);
    int thresholdForShowing = SpamComponent.get(context).spam().percentOfSpamNotificationsToShow();
    if (thresholdForShowing == 0) {
      LogUtil.d(
          "SpamCallListListener.shouldThrottleSpamNotification",
          "not showing - percentOfSpamNotificationsToShow is 0");
      return true;
    } else if (randomNumber < thresholdForShowing) {
      LogUtil.d(
          "SpamCallListListener.shouldThrottleSpamNotification",
          "showing " + randomNumber + " < " + thresholdForShowing);
      return false;
    } else {
      LogUtil.d(
          "SpamCallListListener.shouldThrottleSpamNotification",
          "not showing %d >= %d",
          randomNumber,
          thresholdForShowing);
      return true;
    }
  }

  private boolean shouldThrottleNonSpamNotification() {
    int randomNumber = random.nextInt(100);
    int thresholdForShowing =
        SpamComponent.get(context).spam().percentOfNonSpamNotificationsToShow();
    if (thresholdForShowing == 0) {
      LogUtil.d(
          "SpamCallListListener.shouldThrottleNonSpamNotification",
          "not showing non spam notification: percentOfNonSpamNotificationsToShow is 0");
      return true;
    } else if (randomNumber < thresholdForShowing) {
      LogUtil.d(
          "SpamCallListListener.shouldThrottleNonSpamNotification",
          "showing non spam notification: %d < %d",
          randomNumber,
          thresholdForShowing);
      return false;
    } else {
      LogUtil.d(
          "SpamCallListListener.shouldThrottleNonSpamNotification",
          "not showing non spam notification: %d >= %d",
          randomNumber,
          thresholdForShowing);
      return true;
    }
  }

  private void maybeShowSpamCallNotification(DialerCall call) {
    if (shouldThrottleSpamNotification()) {
      Logger.get(context)
          .logCallImpression(
              DialerImpression.Type.SPAM_NOTIFICATION_NOT_SHOWN_AFTER_THROTTLE,
              call.getUniqueCallId(),
              call.getTimeAddedMs());
    } else {
      Logger.get(context)
          .logCallImpression(
              DialerImpression.Type.SPAM_NOTIFICATION_SHOWN_AFTER_THROTTLE,
              call.getUniqueCallId(),
              call.getTimeAddedMs());
      showSpamCallNotification(call);
    }
  }

  private void maybeShowNonSpamCallNotification(DialerCall call) {
    if (shouldThrottleNonSpamNotification()) {
      Logger.get(context)
          .logCallImpression(
              DialerImpression.Type.NON_SPAM_NOTIFICATION_NOT_SHOWN_AFTER_THROTTLE,
              call.getUniqueCallId(),
              call.getTimeAddedMs());
    } else {
      Logger.get(context)
          .logCallImpression(
              DialerImpression.Type.NON_SPAM_NOTIFICATION_SHOWN_AFTER_THROTTLE,
              call.getUniqueCallId(),
              call.getTimeAddedMs());
      showNonSpamCallNotification(call);
    }
  }

  /** Display a notification with the action "not spam". */
  private void showSpamCallNotification(DialerCall call) {
    Notification.Builder notificationBuilder =
        createAfterCallNotificationBuilder(call)
            .setLargeIcon(Icon.createWithResource(context, R.drawable.spam_notification_icon))
            .setContentText(context.getString(R.string.spam_notification_spam_call_collapsed_text))
            // Not spam
            .addAction(
                new Notification.Action.Builder(
                        R.drawable.quantum_ic_close_vd_theme_24,
                        context.getString(R.string.spam_notification_was_not_spam_action_text),
                        createNotSpamPendingIntent(call))
                    .build())
            // Block/report spam
            .addAction(
                new Notification.Action.Builder(
                        R.drawable.quantum_ic_block_vd_theme_24,
                        context.getString(R.string.spam_notification_block_spam_action_text),
                        createBlockReportSpamPendingIntent(call))
                    .build())
            .setContentTitle(
                context.getString(R.string.spam_notification_title, getDisplayNumber(call)));
    DialerNotificationManager.notify(
        context, getNotificationTagForCall(call), NOTIFICATION_ID, notificationBuilder.build());
  }

  /**
   * Creates a pending intent for block/report spam action. If enabled, this intent is forwarded to
   * the {@link SpamNotificationActivity}, otherwise to the {@link SpamNotificationService}.
   */
  private PendingIntent createBlockReportSpamPendingIntent(DialerCall call) {
    String action = SpamNotificationActivity.ACTION_MARK_NUMBER_AS_SPAM;
    return SpamComponent.get(context).spam().isDialogEnabledForSpamNotification()
        ? createActivityPendingIntent(call, action)
        : createServicePendingIntent(call, action);
  }

  /**
   * Creates a pending intent for not spam action. If enabled, this intent is forwarded to the
   * {@link SpamNotificationActivity}, otherwise to the {@link SpamNotificationService}.
   */
  private PendingIntent createNotSpamPendingIntent(DialerCall call) {
    String action = SpamNotificationActivity.ACTION_MARK_NUMBER_AS_NOT_SPAM;
    return SpamComponent.get(context).spam().isDialogEnabledForSpamNotification()
        ? createActivityPendingIntent(call, action)
        : createServicePendingIntent(call, action);
  }

  /** Creates a pending intent for {@link SpamNotificationService}. */
  private PendingIntent createServicePendingIntent(DialerCall call, String action) {
    Intent intent =
        SpamNotificationService.createServiceIntent(
            context, call, action, getNotificationTagForCall(call), NOTIFICATION_ID);
    return PendingIntent.getService(
        context, (int) System.currentTimeMillis(), intent, PendingIntent.FLAG_ONE_SHOT);
  }

  /** Creates a pending intent for {@link SpamNotificationActivity}. */
  private PendingIntent createActivityPendingIntent(DialerCall call, String action) {
    Intent intent =
        SpamNotificationActivity.createActivityIntent(
            context, call, action, getNotificationTagForCall(call), NOTIFICATION_ID);
    return PendingIntent.getActivity(
        context, (int) System.currentTimeMillis(), intent, PendingIntent.FLAG_ONE_SHOT);
  }

  static String getNotificationTagForCall(@NonNull DialerCall call) {
    return NOTIFICATION_TAG_PREFIX + call.getUniqueCallId();
  }
}