1package eu.siacs.conversations.crypto.sasl;
 2
 3import android.util.Log;
 4
 5import com.google.common.base.CaseFormat;
 6
 7import java.util.Collection;
 8
 9import eu.siacs.conversations.Config;
10
11public enum ChannelBinding {
12    NONE,
13    TLS_EXPORTER,
14    TLS_SERVER_END_POINT,
15    TLS_UNIQUE;
16
17    public static ChannelBinding of(final String type) {
18        if (type == null) {
19            return null;
20        }
21        try {
22            return valueOf(
23                    CaseFormat.LOWER_HYPHEN.converterTo(CaseFormat.UPPER_UNDERSCORE).convert(type));
24        } catch (final IllegalArgumentException e) {
25            Log.d(Config.LOGTAG, type + " is not a known channel binding");
26            return null;
27        }
28    }
29
30    public static ChannelBinding best(final Collection<ChannelBinding> bindings) {
31        if (bindings.contains(TLS_EXPORTER)) {
32            return TLS_EXPORTER;
33        } else if (bindings.contains(TLS_UNIQUE)) {
34            return TLS_UNIQUE;
35        } else if (bindings.contains(TLS_SERVER_END_POINT)) {
36            return TLS_SERVER_END_POINT;
37        } else {
38            return null;
39        }
40    }
41}