package org.thoughtcrime.securesms.util;

import android.accounts.Account;
import android.accounts.AccountManager;
import android.content.ContentResolver;
import android.content.Context;
import android.content.OperationApplicationException;
import android.os.RemoteException;
import android.provider.ContactsContract;
import android.support.annotation.NonNull;
import android.support.annotation.Nullable;
import android.util.Log;
import android.util.Pair;

import org.thoughtcrime.securesms.ApplicationContext;
import org.thoughtcrime.securesms.R;
import org.thoughtcrime.securesms.crypto.MasterSecret;
import org.thoughtcrime.securesms.database.DatabaseFactory;
import org.thoughtcrime.securesms.database.NotInDirectoryException;
import org.thoughtcrime.securesms.database.TextSecureDirectory;
import org.thoughtcrime.securesms.jobs.MultiDeviceContactUpdateJob;
import org.thoughtcrime.securesms.notifications.MessageNotifier;
import org.thoughtcrime.securesms.push.TextSecureCommunicationFactory;
import org.thoughtcrime.securesms.recipients.Recipients;
import org.thoughtcrime.securesms.sms.IncomingJoinedMessage;
import org.thoughtcrime.securesms.util.DirectoryHelper.UserCapabilities.Capability;
import org.whispersystems.libaxolotl.util.guava.Optional;
import org.whispersystems.textsecure.api.TextSecureAccountManager;
import org.whispersystems.textsecure.api.push.ContactTokenDetails;
import org.whispersystems.textsecure.api.util.InvalidNumberException;

import java.io.IOException;
import java.util.LinkedList;
import java.util.List;
import java.util.Set;

public class DirectoryHelper {

  public static class UserCapabilities {

    public static final UserCapabilities UNKNOWN     = new UserCapabilities(Capability.UNKNOWN, Capability.UNKNOWN);
    public static final UserCapabilities UNSUPPORTED = new UserCapabilities(Capability.UNSUPPORTED, Capability.UNSUPPORTED);

    public enum Capability {
      UNKNOWN, SUPPORTED, UNSUPPORTED
    }

    private final Capability text;
    private final Capability voice;

    public UserCapabilities(Capability text, Capability voice) {
      this.text  = text;
      this.voice = voice;
    }

    public Capability getTextCapability() {
      return text;
    }

    public Capability getVoiceCapability() {
      return voice;
    }
  }

  private static final String TAG = DirectoryHelper.class.getSimpleName();

  public static void refreshDirectory(@NonNull Context context, @Nullable MasterSecret masterSecret)
      throws IOException
  {
    List<String> newUsers = refreshDirectory(context,
                                             TextSecureCommunicationFactory.createManager(context),
                                             TextSecurePreferences.getLocalNumber(context));

    if (!newUsers.isEmpty() && TextSecurePreferences.isMultiDevice(context)) {
      ApplicationContext.getInstance(context)
                        .getJobManager()
                        .add(new MultiDeviceContactUpdateJob(context));
    }

    notifyNewUsers(context, masterSecret, newUsers);
  }

  public static @NonNull List<String> refreshDirectory(@NonNull Context context,
                                                       @NonNull TextSecureAccountManager accountManager,
                                                       @NonNull String localNumber)
      throws IOException
  {
    TextSecureDirectory       directory              = TextSecureDirectory.getInstance(context);
    Set<String>               eligibleContactNumbers = directory.getPushEligibleContactNumbers(localNumber);
    List<ContactTokenDetails> activeTokens           = accountManager.getContacts(eligibleContactNumbers);

    if (activeTokens != null) {
      for (ContactTokenDetails activeToken : activeTokens) {
        eligibleContactNumbers.remove(activeToken.getNumber());
        activeToken.setNumber(activeToken.getNumber());
      }

      directory.setNumbers(activeTokens, eligibleContactNumbers);
      return updateContactsDatabase(context, localNumber, activeTokens, true);
    }

    return new LinkedList<>();
  }

  public static UserCapabilities refreshDirectoryFor(@NonNull  Context context,
                                                     @Nullable MasterSecret masterSecret,
                                                     @NonNull  Recipients recipients,
                                                     @NonNull  String localNumber)
      throws IOException
  {
    try {
      TextSecureDirectory           directory      = TextSecureDirectory.getInstance(context);
      TextSecureAccountManager      accountManager = TextSecureCommunicationFactory.createManager(context);
      String                        number         = Util.canonicalizeNumber(context, recipients.getPrimaryRecipient().getNumber());
      Optional<ContactTokenDetails> details        = accountManager.getContact(number);

      if (details.isPresent()) {
        directory.setNumber(details.get(), true);

        List<String> newUsers = updateContactsDatabase(context, localNumber, details.get());

        if (!newUsers.isEmpty() && TextSecurePreferences.isMultiDevice(context)) {
          ApplicationContext.getInstance(context).getJobManager().add(new MultiDeviceContactUpdateJob(context));
        }

        notifyNewUsers(context, masterSecret, newUsers);

        return new UserCapabilities(Capability.SUPPORTED, details.get().isVoice() ? Capability.SUPPORTED : Capability.UNSUPPORTED);
      } else {
        ContactTokenDetails absent = new ContactTokenDetails();
        absent.setNumber(number);
        directory.setNumber(absent, false);
        return UserCapabilities.UNSUPPORTED;
      }
    } catch (InvalidNumberException e) {
      Log.w(TAG, e);
      return UserCapabilities.UNSUPPORTED;
    }
  }

  public static @NonNull UserCapabilities getUserCapabilities(@NonNull Context context,
                                                              @Nullable Recipients recipients)
  {
    try {
      if (recipients == null) {
        return UserCapabilities.UNSUPPORTED;
      }

      if (!TextSecurePreferences.isPushRegistered(context)) {
        return UserCapabilities.UNSUPPORTED;
      }

      if (!recipients.isSingleRecipient()) {
        return UserCapabilities.UNSUPPORTED;
      }

      if (recipients.isGroupRecipient()) {
        return new UserCapabilities(Capability.SUPPORTED, Capability.UNSUPPORTED);
      }

      final String number = recipients.getPrimaryRecipient().getNumber();

      if (number == null) {
        return UserCapabilities.UNSUPPORTED;
      }

      String  e164number  = Util.canonicalizeNumber(context, number);
      boolean secureText  = TextSecureDirectory.getInstance(context).isSecureTextSupported(e164number);
      boolean secureVoice = TextSecureDirectory.getInstance(context).isSecureVoiceSupported(e164number);

      return new UserCapabilities(secureText  ? Capability.SUPPORTED : Capability.UNSUPPORTED,
                                  secureVoice ? Capability.SUPPORTED : Capability.UNSUPPORTED);

    } catch (InvalidNumberException e) {
      Log.w(TAG, e);
      return UserCapabilities.UNSUPPORTED;
    } catch (NotInDirectoryException e) {
      return UserCapabilities.UNKNOWN;
    }
  }

  private static @NonNull List<String> updateContactsDatabase(@NonNull Context context,
                                                              @NonNull String localNumber,
                                                              @NonNull final ContactTokenDetails activeToken)
  {
    return updateContactsDatabase(context, localNumber,
                                  new LinkedList<ContactTokenDetails>() {{add(activeToken);}},
                                  false);
  }

  private static @NonNull List<String> updateContactsDatabase(@NonNull Context context,
                                                              @NonNull String localNumber,
                                                              @NonNull List<ContactTokenDetails> activeTokens,
                                                              boolean removeMissing)
  {
    Optional<Account> account = getOrCreateAccount(context);

    if (account.isPresent()) {
      try {
        return  DatabaseFactory.getContactsDatabase(context)
                               .setRegisteredUsers(account.get(), localNumber, activeTokens, removeMissing);
      } catch (RemoteException | OperationApplicationException e) {
        Log.w(TAG, e);
      }
    }

    return new LinkedList<>();
  }

  private static void notifyNewUsers(@NonNull  Context context,
                                     @Nullable MasterSecret masterSecret,
                                     @NonNull  List<String> newUsers)
  {
    for (String newUser : newUsers) {
      IncomingJoinedMessage message        = new IncomingJoinedMessage(newUser);
      Pair<Long, Long>      smsAndThreadId = DatabaseFactory.getSmsDatabase(context).insertMessageInbox(message);
      MessageNotifier.updateNotification(context, masterSecret, smsAndThreadId.second);
    }
  }

  private static Optional<Account> getOrCreateAccount(Context context) {
    AccountManager accountManager = AccountManager.get(context);
    Account[]      accounts       = accountManager.getAccountsByType("org.thoughtcrime.securesms");

    Optional<Account> account;

    if (accounts.length == 0) account = createAccount(context);
    else                      account = Optional.of(accounts[0]);

    if (account.isPresent() && !ContentResolver.getSyncAutomatically(account.get(), ContactsContract.AUTHORITY)) {
      ContentResolver.setSyncAutomatically(account.get(), ContactsContract.AUTHORITY, true);
    }

    return account;
  }

  private static Optional<Account> createAccount(Context context) {
    AccountManager accountManager = AccountManager.get(context);
    Account        account        = new Account(context.getString(R.string.app_name), "org.thoughtcrime.securesms");

    if (accountManager.addAccountExplicitly(account, null, null)) {
      Log.w(TAG, "Created new account...");
      ContentResolver.setIsSyncable(account, ContactsContract.AUTHORITY, 1);
      return Optional.of(account);
    } else {
      Log.w(TAG, "Failed to create account!");
      return Optional.absent();
    }
  }
}