/*
 * Copyright (C) 2015 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.telecom;

import android.Manifest;
import android.content.Context;
import android.content.Intent;
import android.content.pm.PackageManager;
import android.net.Uri;
import android.provider.CallLog.Calls;
import android.support.annotation.Nullable;
import android.support.annotation.VisibleForTesting;
import android.support.v4.content.ContextCompat;
import android.telecom.PhoneAccount;
import android.telecom.PhoneAccountHandle;
import android.telecom.TelecomManager;
import android.text.TextUtils;
import com.android.dialer.common.LogUtil;
import java.util.ArrayList;
import java.util.List;

/**
 * Performs permission checks before calling into TelecomManager. Each method is self-explanatory -
 * perform the required check and return the fallback default if the permission is missing,
 * otherwise return the value from TelecomManager.
 */
public class TelecomUtil {

  private static final String TAG = "TelecomUtil";
  private static boolean sWarningLogged = false;
  private static Boolean isDefaultDialerForTesting;
  private static Boolean hasPermissionForTesting;

  public static void showInCallScreen(Context context, boolean showDialpad) {
    if (hasReadPhoneStatePermission(context)) {
      try {
        getTelecomManager(context).showInCallScreen(showDialpad);
      } catch (SecurityException e) {
        // Just in case
        LogUtil.w(TAG, "TelecomManager.showInCallScreen called without permission.");
      }
    }
  }

  public static void silenceRinger(Context context) {
    if (hasModifyPhoneStatePermission(context)) {
      try {
        getTelecomManager(context).silenceRinger();
      } catch (SecurityException e) {
        // Just in case
        LogUtil.w(TAG, "TelecomManager.silenceRinger called without permission.");
      }
    }
  }

  public static void cancelMissedCallsNotification(Context context) {
    if (hasModifyPhoneStatePermission(context)) {
      try {
        getTelecomManager(context).cancelMissedCallsNotification();
      } catch (SecurityException e) {
        LogUtil.w(TAG, "TelecomManager.cancelMissedCalls called without permission.");
      }
    }
  }

  public static Uri getAdnUriForPhoneAccount(Context context, PhoneAccountHandle handle) {
    if (hasModifyPhoneStatePermission(context)) {
      try {
        return getTelecomManager(context).getAdnUriForPhoneAccount(handle);
      } catch (SecurityException e) {
        LogUtil.w(TAG, "TelecomManager.getAdnUriForPhoneAccount called without permission.");
      }
    }
    return null;
  }

  public static boolean handleMmi(
      Context context, String dialString, @Nullable PhoneAccountHandle handle) {
    if (hasModifyPhoneStatePermission(context)) {
      try {
        if (handle == null) {
          return getTelecomManager(context).handleMmi(dialString);
        } else {
          return getTelecomManager(context).handleMmi(dialString, handle);
        }
      } catch (SecurityException e) {
        LogUtil.w(TAG, "TelecomManager.handleMmi called without permission.");
      }
    }
    return false;
  }

  @Nullable
  public static PhoneAccountHandle getDefaultOutgoingPhoneAccount(
      Context context, String uriScheme) {
    if (hasReadPhoneStatePermission(context)) {
      return getTelecomManager(context).getDefaultOutgoingPhoneAccount(uriScheme);
    }
    return null;
  }

  public static PhoneAccount getPhoneAccount(Context context, PhoneAccountHandle handle) {
    return getTelecomManager(context).getPhoneAccount(handle);
  }

  public static List<PhoneAccountHandle> getCallCapablePhoneAccounts(Context context) {
    if (hasReadPhoneStatePermission(context)) {
      return getTelecomManager(context).getCallCapablePhoneAccounts();
    }
    return new ArrayList<>();
  }

  public static boolean isInCall(Context context) {
    if (hasReadPhoneStatePermission(context)) {
      return getTelecomManager(context).isInCall();
    }
    return false;
  }

  public static boolean isVoicemailNumber(
      Context context, PhoneAccountHandle accountHandle, String number) {
    if (hasReadPhoneStatePermission(context)) {
      return getTelecomManager(context).isVoiceMailNumber(accountHandle, number);
    }
    return false;
  }

  @Nullable
  public static String getVoicemailNumber(Context context, PhoneAccountHandle accountHandle) {
    if (hasReadPhoneStatePermission(context)) {
      return getTelecomManager(context).getVoiceMailNumber(accountHandle);
    }
    return null;
  }

  /**
   * Tries to place a call using the {@link TelecomManager}.
   *
   * @param context context.
   * @param intent the call intent.
   * @return {@code true} if we successfully attempted to place the call, {@code false} if it failed
   *     due to a permission check.
   */
  public static boolean placeCall(Context context, Intent intent) {
    if (hasCallPhonePermission(context)) {
      getTelecomManager(context).placeCall(intent.getData(), intent.getExtras());
      return true;
    }
    return false;
  }

  public static Uri getCallLogUri(Context context) {
    return hasReadWriteVoicemailPermissions(context)
        ? Calls.CONTENT_URI_WITH_VOICEMAIL
        : Calls.CONTENT_URI;
  }

  public static boolean hasReadWriteVoicemailPermissions(Context context) {
    return isDefaultDialer(context)
        || (hasPermission(context, Manifest.permission.READ_VOICEMAIL)
            && hasPermission(context, Manifest.permission.WRITE_VOICEMAIL));
  }

  public static boolean hasModifyPhoneStatePermission(Context context) {
    return isDefaultDialer(context)
        || hasPermission(context, Manifest.permission.MODIFY_PHONE_STATE);
  }

  public static boolean hasReadPhoneStatePermission(Context context) {
    return isDefaultDialer(context) || hasPermission(context, Manifest.permission.READ_PHONE_STATE);
  }

  public static boolean hasCallPhonePermission(Context context) {
    return isDefaultDialer(context) || hasPermission(context, Manifest.permission.CALL_PHONE);
  }

  private static boolean hasPermission(Context context, String permission) {
    if (hasPermissionForTesting != null) {
      return hasPermissionForTesting;
    }
    return ContextCompat.checkSelfPermission(context, permission)
        == PackageManager.PERMISSION_GRANTED;
  }

  public static boolean isDefaultDialer(Context context) {
    if (isDefaultDialerForTesting != null) {
      return isDefaultDialerForTesting;
    }
    final boolean result =
        TextUtils.equals(
            context.getPackageName(), getTelecomManager(context).getDefaultDialerPackage());
    if (result) {
      sWarningLogged = false;
    } else {
      if (!sWarningLogged) {
        // Log only once to prevent spam.
        LogUtil.w(TAG, "Dialer is not currently set to be default dialer");
        sWarningLogged = true;
      }
    }
    return result;
  }

  private static TelecomManager getTelecomManager(Context context) {
    return (TelecomManager) context.getSystemService(Context.TELECOM_SERVICE);
  }

  @VisibleForTesting(otherwise = VisibleForTesting.NONE)
  public static void setIsDefaultDialerForTesting(Boolean defaultDialer) {
    isDefaultDialerForTesting = defaultDialer;
  }

  @VisibleForTesting(otherwise = VisibleForTesting.NONE)
  public static void setHasPermissionForTesting(Boolean hasPermission) {
    hasPermissionForTesting = hasPermission;
  }
}