Implement support for sending disappearing messages

Stores the expiration timeout received from contacts in the config file

Fixes #27

src/main/java/org/asamk/signal/JsonThreadStore.java

@@ -0,0 +1,56 @@
+package org.asamk.signal;
+
+import com.fasterxml.jackson.annotation.JsonProperty;
+import com.fasterxml.jackson.core.JsonGenerator;
+import com.fasterxml.jackson.core.JsonParser;
+import com.fasterxml.jackson.databind.*;
+import com.fasterxml.jackson.databind.annotation.JsonDeserialize;
+import com.fasterxml.jackson.databind.annotation.JsonSerialize;
+
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+
+public class JsonThreadStore {
+    @JsonProperty("threads")
+    @JsonSerialize(using = JsonThreadStore.MapToListSerializer.class)
+    @JsonDeserialize(using = ThreadsDeserializer.class)
+    private Map<String, ThreadInfo> threads = new HashMap<>();
+
+    private static final ObjectMapper jsonProcessor = new ObjectMapper();
+
+    void updateThread(ThreadInfo thread) {
+        threads.put(thread.id, thread);
+    }
+
+    ThreadInfo getThread(String id) {
+        return threads.get(id);
+    }
+
+    List<ThreadInfo> getThreads() {
+        return new ArrayList<>(threads.values());
+    }
+
+    public static class MapToListSerializer extends JsonSerializer<Map<?, ?>> {
+        @Override
+        public void serialize(final Map<?, ?> value, final JsonGenerator jgen, final SerializerProvider provider) throws IOException {
+            jgen.writeObject(value.values());
+        }
+    }
+
+    public static class ThreadsDeserializer extends JsonDeserializer<Map<String, ThreadInfo>> {
+        @Override
+        public Map<String, ThreadInfo> deserialize(JsonParser jsonParser, DeserializationContext deserializationContext) throws IOException {
+            Map<String, ThreadInfo> threads = new HashMap<>();
+            JsonNode node = jsonParser.getCodec().readTree(jsonParser);
+            for (JsonNode n : node) {
+                ThreadInfo t = jsonProcessor.treeToValue(n, ThreadInfo.class);
+                threads.put(t.id, t);
+            }
+
+            return threads;
+        }
+    }
+}