/*
 * Copyright (C) 2011 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.voicemailstatus;

import static android.provider.VoicemailContract.Status.CONFIGURATION_STATE_CAN_BE_CONFIGURED;
import static android.provider.VoicemailContract.Status.CONFIGURATION_STATE_OK;
import static android.provider.VoicemailContract.Status.DATA_CHANNEL_STATE_NO_CONNECTION;
import static android.provider.VoicemailContract.Status.DATA_CHANNEL_STATE_OK;
import static android.provider.VoicemailContract.Status.NOTIFICATION_CHANNEL_STATE_MESSAGE_WAITING;
import static android.provider.VoicemailContract.Status.NOTIFICATION_CHANNEL_STATE_NO_CONNECTION;
import static android.provider.VoicemailContract.Status.NOTIFICATION_CHANNEL_STATE_OK;

import android.database.Cursor;
import android.net.Uri;
import android.provider.VoicemailContract.Status;
import com.android.contacts.common.util.UriUtils;
import com.android.dialer.database.VoicemailStatusQuery;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;
import java.util.List;

/** Implementation of {@link VoicemailStatusHelper}. */
public class VoicemailStatusHelperImpl implements VoicemailStatusHelper {

  @Override
  public List<StatusMessage> getStatusMessages(Cursor cursor) {
    List<MessageStatusWithPriority> messages =
        new ArrayList<VoicemailStatusHelperImpl.MessageStatusWithPriority>();
    cursor.moveToPosition(-1);
    while (cursor.moveToNext()) {
      MessageStatusWithPriority message = getMessageForStatusEntry(cursor);
      if (message != null) {
        messages.add(message);
      }
    }
    // Finally reorder the messages by their priority.
    return reorderMessages(messages);
  }

  @Override
  public int getNumberActivityVoicemailSources(Cursor cursor) {
    int count = 0;
    cursor.moveToPosition(-1);
    while (cursor.moveToNext()) {
      if (isVoicemailSourceActive(cursor)) {
        ++count;
      }
    }
    return count;
  }

  /**
   * Returns whether the source status in the cursor corresponds to an active source. A source is
   * active if its' configuration state is not NOT_CONFIGURED. For most voicemail sources, only OK
   * and NOT_CONFIGURED are used. The OMTP visual voicemail client has the same behavior pre-NMR1.
   * NMR1 visual voicemail will only set it to NOT_CONFIGURED when it is deactivated. As soon as
   * activation is attempted, it will transition into CONFIGURING then into OK or other error state,
   * NOT_CONFIGURED is never set through an error.
   */
  private boolean isVoicemailSourceActive(Cursor cursor) {
    return cursor.getString(VoicemailStatusQuery.SOURCE_PACKAGE_INDEX) != null
        && cursor.getInt(VoicemailStatusQuery.CONFIGURATION_STATE_INDEX)
            != Status.CONFIGURATION_STATE_NOT_CONFIGURED;
  }

  private List<StatusMessage> reorderMessages(List<MessageStatusWithPriority> messageWrappers) {
    Collections.sort(
        messageWrappers,
        new Comparator<MessageStatusWithPriority>() {
          @Override
          public int compare(MessageStatusWithPriority msg1, MessageStatusWithPriority msg2) {
            return msg1.mPriority - msg2.mPriority;
          }
        });
    List<StatusMessage> reorderMessages = new ArrayList<VoicemailStatusHelper.StatusMessage>();
    // Copy the ordered message objects into the final list.
    for (MessageStatusWithPriority messageWrapper : messageWrappers) {
      reorderMessages.add(messageWrapper.mMessage);
    }
    return reorderMessages;
  }

  /** Returns the message for the status entry pointed to by the cursor. */
  private MessageStatusWithPriority getMessageForStatusEntry(Cursor cursor) {
    final String sourcePackage = cursor.getString(VoicemailStatusQuery.SOURCE_PACKAGE_INDEX);
    if (sourcePackage == null) {
      return null;
    }
    final OverallState overallState =
        getOverallState(
            cursor.getInt(VoicemailStatusQuery.CONFIGURATION_STATE_INDEX),
            cursor.getInt(VoicemailStatusQuery.DATA_CHANNEL_STATE_INDEX),
            cursor.getInt(VoicemailStatusQuery.NOTIFICATION_CHANNEL_STATE_INDEX));
    final Action action = overallState.getAction();

    // No source package or no action, means no message shown.
    if (action == Action.NONE) {
      return null;
    }

    Uri actionUri = null;
    if (action == Action.CALL_VOICEMAIL) {
      actionUri =
          UriUtils.parseUriOrNull(
              cursor.getString(VoicemailStatusQuery.VOICEMAIL_ACCESS_URI_INDEX));
      // Even if actionUri is null, it is still be useful to show the notification.
    } else if (action == Action.CONFIGURE_VOICEMAIL) {
      actionUri =
          UriUtils.parseUriOrNull(cursor.getString(VoicemailStatusQuery.SETTINGS_URI_INDEX));
      // If there is no settings URI, there is no point in showing the notification.
      if (actionUri == null) {
        return null;
      }
    }
    return new MessageStatusWithPriority(
        new StatusMessage(
            sourcePackage,
            overallState.getCallLogMessageId(),
            overallState.getCallDetailsMessageId(),
            action.getMessageId(),
            actionUri),
        overallState.getPriority());
  }

  private OverallState getOverallState(
      int configurationState, int dataChannelState, int notificationChannelState) {
    if (configurationState == CONFIGURATION_STATE_OK) {
      // Voicemail is configured. Let's see how is the data channel.
      if (dataChannelState == DATA_CHANNEL_STATE_OK) {
        // Data channel is fine. What about notification channel?
        if (notificationChannelState == NOTIFICATION_CHANNEL_STATE_OK) {
          return OverallState.OK;
        } else if (notificationChannelState == NOTIFICATION_CHANNEL_STATE_MESSAGE_WAITING) {
          return OverallState.NO_DETAILED_NOTIFICATION;
        } else if (notificationChannelState == NOTIFICATION_CHANNEL_STATE_NO_CONNECTION) {
          return OverallState.NO_NOTIFICATIONS;
        }
      } else if (dataChannelState == DATA_CHANNEL_STATE_NO_CONNECTION) {
        // Data channel is not working. What about notification channel?
        if (notificationChannelState == NOTIFICATION_CHANNEL_STATE_OK) {
          return OverallState.NO_DATA;
        } else if (notificationChannelState == NOTIFICATION_CHANNEL_STATE_MESSAGE_WAITING) {
          return OverallState.MESSAGE_WAITING;
        } else if (notificationChannelState == NOTIFICATION_CHANNEL_STATE_NO_CONNECTION) {
          return OverallState.NO_CONNECTION;
        }
      }
    } else if (configurationState == CONFIGURATION_STATE_CAN_BE_CONFIGURED) {
      // Voicemail not configured. data/notification channel states are irrelevant.
      return OverallState.INVITE_FOR_CONFIGURATION;
    } else if (configurationState == Status.CONFIGURATION_STATE_NOT_CONFIGURED) {
      // Voicemail not configured. data/notification channel states are irrelevant.
      return OverallState.NOT_CONFIGURED;
    }
    // Will reach here only if the source has set an invalid value.
    return OverallState.INVALID;
  }

  /** Possible user actions. */
  public enum Action {
    NONE(-1),
    CALL_VOICEMAIL(R.string.voicemail_status_action_call_server),
    CONFIGURE_VOICEMAIL(R.string.voicemail_status_action_configure);

    private final int mMessageId;

    Action(int messageId) {
      mMessageId = messageId;
    }

    public int getMessageId() {
      return mMessageId;
    }
  }

  /**
   * Overall state of the source status. Each state is associated with the corresponding display
   * string and the corrective action. The states are also assigned a relative priority which is
   * used to order the messages from different sources.
   */
  private enum OverallState {
    // TODO: Add separate string for call details and call log pages for the states that needs
    // to be shown in both.
    /** Both notification and data channel are not working. */
    NO_CONNECTION(
        0,
        Action.CALL_VOICEMAIL,
        R.string.voicemail_status_voicemail_not_available,
        R.string.voicemail_status_audio_not_available),
    /** Notifications working, but data channel is not working. Audio cannot be downloaded. */
    NO_DATA(
        1,
        Action.CALL_VOICEMAIL,
        R.string.voicemail_status_voicemail_not_available,
        R.string.voicemail_status_audio_not_available),
    /** Messages are known to be waiting but data channel is not working. */
    MESSAGE_WAITING(
        2,
        Action.CALL_VOICEMAIL,
        R.string.voicemail_status_messages_waiting,
        R.string.voicemail_status_audio_not_available),
    /** Notification channel not working, but data channel is. */
    NO_NOTIFICATIONS(3, Action.CALL_VOICEMAIL, R.string.voicemail_status_voicemail_not_available),
    /** Invite user to set up voicemail. */
    INVITE_FOR_CONFIGURATION(
        4, Action.CONFIGURE_VOICEMAIL, R.string.voicemail_status_configure_voicemail),
    /**
     * No detailed notifications, but data channel is working. This is normal mode of operation for
     * certain sources. No action needed.
     */
    NO_DETAILED_NOTIFICATION(5, Action.NONE, -1),
    /** Visual voicemail not yet set up. No local action needed. */
    NOT_CONFIGURED(6, Action.NONE, -1),
    /** Everything is OK. */
    OK(7, Action.NONE, -1),
    /** If one or more state value set by the source is not valid. */
    INVALID(8, Action.NONE, -1);

    private final int mPriority;
    private final Action mAction;
    private final int mCallLogMessageId;
    private final int mCallDetailsMessageId;

    OverallState(int priority, Action action, int callLogMessageId) {
      this(priority, action, callLogMessageId, -1);
    }

    OverallState(int priority, Action action, int callLogMessageId, int callDetailsMessageId) {
      mPriority = priority;
      mAction = action;
      mCallLogMessageId = callLogMessageId;
      mCallDetailsMessageId = callDetailsMessageId;
    }

    public Action getAction() {
      return mAction;
    }

    public int getPriority() {
      return mPriority;
    }

    public int getCallLogMessageId() {
      return mCallLogMessageId;
    }

    public int getCallDetailsMessageId() {
      return mCallDetailsMessageId;
    }
  }

  /** A wrapper on {@link StatusMessage} which additionally stores the priority of the message. */
  private static class MessageStatusWithPriority {

    private final StatusMessage mMessage;
    private final int mPriority;

    public MessageStatusWithPriority(StatusMessage message, int priority) {
      mMessage = message;
      mPriority = priority;
    }
  }
}