Mercury-IM/domain/src/main/java/org/mercury_im/messenger/xmpp/MercuryConnection.java

package org.mercury_im.messenger.xmpp;

import org.jivesoftware.smack.ConnectionListener;
import org.jivesoftware.smack.XMPPConnection;
import org.mercury_im.messenger.data.repository.AccountRepository;
import org.mercury_im.messenger.entity.Account;
import org.mercury_im.messenger.util.Optional;

import io.reactivex.Observable;
import io.reactivex.disposables.CompositeDisposable;
import io.reactivex.subjects.BehaviorSubject;

public class MercuryConnection {

    private static final XmppConnectionFactory connectionFactory = new XmppConnectionFactory();

    private final CompositeDisposable disposable = new CompositeDisposable();
    private final AccountRepository accountRepository;

    private Account account;
    private XMPPConnection connection;

    private BehaviorSubject<Boolean> enabled = BehaviorSubject.create();
    private BehaviorSubject<ConnectionState> state = BehaviorSubject.createDefault(ConnectionState.closed);

    public MercuryConnection(AccountRepository accountRepository, Account account) {
        this.accountRepository = accountRepository;
        this.account = account;
        this.connection = connectionFactory.createConnection(account);
        observeAccountAndConnection();
    }

    public Observable<ConnectionState> getState() {
        return state;
    }

    private void observeAccountAndConnection() {
        observeAccount();
        observeConnection();
    }

    private void observeAccount() {
        disposable.add(accountRepository.observeAccount(account.getId())
                .filter(Optional::isPresent)
                .map(Optional::getItem)
                .subscribe(this::setAccount));
    }

    private void observeConnection() {
        connection.addConnectionListener(new ConnectionListener() {
            @Override
            public void connected(XMPPConnection connection) {
                state.onNext(ConnectionState.connected);
            }

            @Override
            public void authenticated(XMPPConnection connection, boolean resumed) {
                state.onNext(ConnectionState.authenticated);
            }

            @Override
            public void connectionClosed() {
                state.onNext(ConnectionState.closed);
            }

            @Override
            public void connectionClosedOnError(Exception e) {
                state.onNext(ConnectionState.closedOnError);
            }
        });
    }

    private void setAccount(Account account) {
        this.account = account;
        enabled.onNext(account.isEnabled());
    }

    public Account getAccount() {
        return account;
    }

    public XMPPConnection getConnection() {
        return connection;
    }

    public void dispose() {
        disposable.dispose();
    }

    public enum ConnectionState {
        connected,
        authenticated,
        closedOnError,
        closed
    }
}