package app.fedilab.android.mastodon.broadcastreceiver;
/* Copyright 2021 Thomas Schneider
 *
 * This file is a part of Fedilab
 *
 * This program is free software; you can redistribute it and/or modify it under the terms of the
 * GNU General Public License as published by the Free Software Foundation; either version 3 of the
 * License, or (at your option) any later version.
 *
 * Fedilab is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even
 * the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
 * Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along with Fedilab; if not,
 * see <http://www.gnu.org/licenses>. */

import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.net.ConnectivityManager;
import android.net.NetworkInfo;

import java.util.HashSet;
import java.util.Set;


/**
 * Original work from <a href="https://stackoverflow.com/a/25873554">stackoverflow</a>
 */
public class NetworkStateReceiver extends BroadcastReceiver {

    protected Set<NetworkStateReceiverListener> listeners;
    protected Boolean connected;

    public NetworkStateReceiver() {
        listeners = new HashSet<>();
        connected = null;
    }

    @Override
    public void onReceive(Context context, Intent intent) {
        if (intent == null || intent.getExtras() == null)
            return;
        ConnectivityManager manager = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
        NetworkInfo ni = manager.getActiveNetworkInfo();
        if (ni != null && ni.getState() == NetworkInfo.State.CONNECTED) {
            connected = true;
        } else if (intent.getBooleanExtra(ConnectivityManager.EXTRA_NO_CONNECTIVITY, Boolean.FALSE)) {
            connected = false;
        }
        notifyStateToAll();
    }


    private void notifyStateToAll() {
        for (NetworkStateReceiverListener listener : listeners)
            notifyState(listener);
    }

    private void notifyState(NetworkStateReceiverListener listener) {
        if (connected == null || listener == null)
            return;
        if (connected)
            listener.networkAvailable();
        else
            listener.networkUnavailable();
    }

    public void addListener(NetworkStateReceiverListener l) {
        listeners.add(l);
        notifyState(l);
    }

    public void removeListener(NetworkStateReceiverListener l) {
        listeners.remove(l);
    }

    public interface NetworkStateReceiverListener {
        void networkAvailable();

        void networkUnavailable();
    }
}