/*
 * 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.precall.impl;

import android.app.Activity;
import android.content.ContentResolver;
import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.net.Uri;
import android.provider.ContactsContract.PhoneLookup;
import android.support.annotation.MainThread;
import android.support.annotation.NonNull;
import android.support.annotation.Nullable;
import android.support.annotation.VisibleForTesting;
import android.support.annotation.WorkerThread;
import android.support.v4.util.ArraySet;
import android.telecom.PhoneAccount;
import android.telecom.PhoneAccountHandle;
import android.telecom.TelecomManager;
import com.android.contacts.common.widget.SelectPhoneAccountDialogFragment;
import com.android.contacts.common.widget.SelectPhoneAccountDialogFragment.SelectPhoneAccountListener;
import com.android.dialer.callintent.CallIntentBuilder;
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.DialerExecutorComponent;
import com.android.dialer.configprovider.ConfigProviderBindings;
import com.android.dialer.precall.PreCallAction;
import com.android.dialer.precall.PreCallCoordinator;
import com.android.dialer.precall.PreCallCoordinator.PendingAction;
import com.android.dialer.preferredsim.PreferredSimFallbackContract;
import com.android.dialer.preferredsim.PreferredSimFallbackContract.PreferredSim;
import com.android.dialer.preferredsim.suggestion.SimSuggestionComponent;
import com.android.dialer.preferredsim.suggestion.SuggestionProvider.Suggestion;
import com.google.common.base.Optional;
import java.util.List;
import java.util.Set;

/** PreCallAction to select which phone account to call with. Ignored if there's only one account */
@SuppressWarnings("MissingPermission")
public class CallingAccountSelector implements PreCallAction {

  @VisibleForTesting static final String TAG_CALLING_ACCOUNT_SELECTOR = "CallingAccountSelector";

  private SelectPhoneAccountDialogFragment selectPhoneAccountDialogFragment;

  private boolean isDiscarding;

  @Override
  public boolean requiresUi(Context context, CallIntentBuilder builder) {
    if (!ConfigProviderBindings.get(context)
        .getBoolean("precall_calling_account_selector_enabled", true)) {
      return false;
    }

    if (builder.getPhoneAccountHandle() != null) {
      return false;
    }
    TelecomManager telecomManager = context.getSystemService(TelecomManager.class);
    List<PhoneAccountHandle> accounts = telecomManager.getCallCapablePhoneAccounts();
    if (accounts.size() <= 1) {
      return false;
    }
    return true;
  }

  @Override
  public void runWithoutUi(Context context, CallIntentBuilder builder) {
    // do nothing.
  }

  @Override
  public void runWithUi(PreCallCoordinator coordinator) {
    CallIntentBuilder builder = coordinator.getBuilder();
    if (!requiresUi(coordinator.getActivity(), builder)) {
      return;
    }
    switch (builder.getUri().getScheme()) {
      case PhoneAccount.SCHEME_VOICEMAIL:
        showDialog(coordinator, coordinator.startPendingAction(), null, null, null);
        break;
      case PhoneAccount.SCHEME_TEL:
        processPreferredAccount(coordinator);
        break;
      default:
        // might be PhoneAccount.SCHEME_SIP
        LogUtil.e(
            "CallingAccountSelector.run",
            "unable to process scheme " + builder.getUri().getScheme());
        break;
    }
  }

  /** Initiates a background worker to find if there's any preferred account. */
  @MainThread
  private void processPreferredAccount(PreCallCoordinator coordinator) {
    Assert.isMainThread();
    CallIntentBuilder builder = coordinator.getBuilder();
    Activity activity = coordinator.getActivity();
    String phoneNumber = builder.getUri().getSchemeSpecificPart();
    PendingAction pendingAction = coordinator.startPendingAction();
    DialerExecutorComponent.get(coordinator.getActivity())
        .dialerExecutorFactory()
        .createUiTaskBuilder(
            activity.getFragmentManager(),
            "PreferredAccountWorker",
            new PreferredAccountWorker(phoneNumber))
        .onSuccess(
            (result -> {
              if (result.phoneAccountHandle.isPresent()) {
                coordinator.getBuilder().setPhoneAccountHandle(result.phoneAccountHandle.get());
                pendingAction.finish();
                return;
              }
              PhoneAccountHandle defaultPhoneAccount =
                  activity
                      .getSystemService(TelecomManager.class)
                      .getDefaultOutgoingPhoneAccount(builder.getUri().getScheme());
              if (defaultPhoneAccount != null) {
                builder.setPhoneAccountHandle(defaultPhoneAccount);
                pendingAction.finish();
                return;
              }
              if (result.suggestion.isPresent()) {
                LogUtil.i(
                    "CallingAccountSelector.processPreferredAccount",
                    "SIM suggested: " + result.suggestion.get().reason);
              }
              showDialog(
                  coordinator,
                  pendingAction,
                  result.dataId.orNull(),
                  phoneNumber,
                  result.suggestion.orNull());
            }))
        .build()
        .executeParallel(activity);
  }

  @MainThread
  private void showDialog(
      PreCallCoordinator coordinator,
      PendingAction pendingAction,
      @Nullable String dataId,
      @Nullable String number,
      @Nullable Suggestion unusedSuggestion) { // TODO(twyen): incoporate suggestion in dialog
    Assert.isMainThread();
    selectPhoneAccountDialogFragment =
        SelectPhoneAccountDialogFragment.newInstance(
            R.string.pre_call_select_phone_account,
            dataId != null /* canSetDefault */,
            coordinator
                .getActivity()
                .getSystemService(TelecomManager.class)
                .getCallCapablePhoneAccounts(),
            new SelectedListener(coordinator, pendingAction, dataId, number),
            null /* call ID */);
    selectPhoneAccountDialogFragment.show(
        coordinator.getActivity().getFragmentManager(), TAG_CALLING_ACCOUNT_SELECTOR);
  }

  @MainThread
  @Override
  public void onDiscard() {
    isDiscarding = true;
    selectPhoneAccountDialogFragment.dismiss();
  }

  private static class PreferredAccountWorkerResult {

    /** The preferred phone account for the number. Absent if not set or invalid. */
    Optional<PhoneAccountHandle> phoneAccountHandle = Optional.absent();

    /**
     * {@link android.provider.ContactsContract.Data#_ID} of the row matching the number. If the
     * preferred account is to be set it should be stored in this row
     */
    Optional<String> dataId = Optional.absent();

    Optional<Suggestion> suggestion = Optional.absent();
  }

  private static class PreferredAccountWorker
      implements Worker<Context, PreferredAccountWorkerResult> {

    private final String phoneNumber;

    public PreferredAccountWorker(String phoneNumber) {
      this.phoneNumber = phoneNumber;
    }

    @NonNull
    @Override
    @WorkerThread
    public PreferredAccountWorkerResult doInBackground(Context context) throws Throwable {
      PreferredAccountWorkerResult result = new PreferredAccountWorkerResult();
      result.dataId = getDataId(context.getContentResolver(), phoneNumber);
      if (result.dataId.isPresent()) {
        result.phoneAccountHandle = getPreferredAccount(context, result.dataId.get());
      }
      if (!result.phoneAccountHandle.isPresent()) {
        result.suggestion =
            SimSuggestionComponent.get(context)
                .getSuggestionProvider()
                .getSuggestion(context, phoneNumber);
      }
      return result;
    }
  }

  @WorkerThread
  @NonNull
  private static Optional<String> getDataId(
      @NonNull ContentResolver contentResolver, @Nullable String phoneNumber) {
    Assert.isWorkerThread();
    try (Cursor cursor =
        contentResolver.query(
            Uri.withAppendedPath(PhoneLookup.CONTENT_FILTER_URI, Uri.encode(phoneNumber)),
            new String[] {PhoneLookup.DATA_ID},
            null,
            null,
            null)) {
      if (cursor == null) {
        return Optional.absent();
      }
      Set<String> result = new ArraySet<>();
      while (cursor.moveToNext()) {
        result.add(cursor.getString(0));
      }
      // TODO(twyen): if there are multiples attempt to grab from the contact that initiated the
      // call.
      if (result.size() == 1) {
        return Optional.of(result.iterator().next());
      } else {
        LogUtil.i("CallingAccountSelector.getDataId", "lookup result not unique, ignoring");
        return Optional.absent();
      }
    }
  }

  @WorkerThread
  @NonNull
  private static Optional<PhoneAccountHandle> getPreferredAccount(
      @NonNull Context context, @NonNull String dataId) {
    Assert.isWorkerThread();
    Assert.isNotNull(dataId);
    try (Cursor cursor =
        context
            .getContentResolver()
            .query(
                PreferredSimFallbackContract.CONTENT_URI,
                new String[] {
                  PreferredSim.PREFERRED_PHONE_ACCOUNT_COMPONENT_NAME,
                  PreferredSim.PREFERRED_PHONE_ACCOUNT_ID
                },
                PreferredSim.DATA_ID + " = ?",
                new String[] {dataId},
                null)) {
      if (cursor == null) {
        return Optional.absent();
      }
      if (!cursor.moveToFirst()) {
        return Optional.absent();
      }
      return PreferredAccountUtil.getValidPhoneAccount(
          context, cursor.getString(0), cursor.getString(1));
    }
  }

  private class SelectedListener extends SelectPhoneAccountListener {

    private final PreCallCoordinator coordinator;
    private final PreCallCoordinator.PendingAction listener;
    private final String dataId;
    private final String number;

    public SelectedListener(
        @NonNull PreCallCoordinator builder,
        @NonNull PreCallCoordinator.PendingAction listener,
        @Nullable String dataId,
        @Nullable String number) {
      this.coordinator = Assert.isNotNull(builder);
      this.listener = Assert.isNotNull(listener);
      this.dataId = dataId;
      this.number = number;
    }

    @MainThread
    @Override
    public void onPhoneAccountSelected(
        PhoneAccountHandle selectedAccountHandle, boolean setDefault, @Nullable String callId) {
      coordinator.getBuilder().setPhoneAccountHandle(selectedAccountHandle);

      if (dataId != null && setDefault) {
        DialerExecutorComponent.get(coordinator.getActivity())
            .dialerExecutorFactory()
            .createNonUiTaskBuilder(new WritePreferredAccountWorker())
            .build()
            .executeParallel(
                new WritePreferredAccountWorkerInput(
                    coordinator.getActivity(), dataId, selectedAccountHandle));
      }
      DialerExecutorComponent.get(coordinator.getActivity())
          .dialerExecutorFactory()
          .createNonUiTaskBuilder(new UserSelectionReporter(selectedAccountHandle, number))
          .build()
          .executeParallel(coordinator.getActivity());
      listener.finish();
    }

    @MainThread
    @Override
    public void onDialogDismissed(@Nullable String callId) {
      if (isDiscarding) {
        return;
      }
      coordinator.abortCall();
      listener.finish();
    }
  }

  private static class UserSelectionReporter implements Worker<Context, Void> {

    private final String number;
    private final PhoneAccountHandle phoneAccountHandle;

    public UserSelectionReporter(
        @NonNull PhoneAccountHandle phoneAccountHandle, @Nullable String number) {
      this.phoneAccountHandle = Assert.isNotNull(phoneAccountHandle);
      this.number = Assert.isNotNull(number);
    }

    @Nullable
    @Override
    public Void doInBackground(@NonNull Context context) throws Throwable {
      SimSuggestionComponent.get(context)
          .getSuggestionProvider()
          .reportUserSelection(context, number, phoneAccountHandle);
      return null;
    }
  }

  private static class WritePreferredAccountWorkerInput {
    private final Context context;
    private final String dataId;
    private final PhoneAccountHandle phoneAccountHandle;

    WritePreferredAccountWorkerInput(
        @NonNull Context context,
        @NonNull String dataId,
        @NonNull PhoneAccountHandle phoneAccountHandle) {
      this.context = Assert.isNotNull(context);
      this.dataId = Assert.isNotNull(dataId);
      this.phoneAccountHandle = Assert.isNotNull(phoneAccountHandle);
    }
  }

  private static class WritePreferredAccountWorker
      implements Worker<WritePreferredAccountWorkerInput, Void> {

    @Nullable
    @Override
    @WorkerThread
    public Void doInBackground(WritePreferredAccountWorkerInput input) throws Throwable {
      ContentValues values = new ContentValues();
      values.put(
          PreferredSim.PREFERRED_PHONE_ACCOUNT_COMPONENT_NAME,
          input.phoneAccountHandle.getComponentName().flattenToString());
      values.put(PreferredSim.PREFERRED_PHONE_ACCOUNT_ID, input.phoneAccountHandle.getId());
      input
          .context
          .getContentResolver()
          .update(
              PreferredSimFallbackContract.CONTENT_URI,
              values,
              PreferredSim.DATA_ID + " = ?",
              new String[] {String.valueOf(input.dataId)});
      return null;
    }
  }
}