Added local contacts

app/src/main/java/eu/faircode/email/EntityContact.java

@@ -0,0 +1,81 @@
+package eu.faircode.email;
+
+/*
+    This file is part of FairEmail.
+
+    FairEmail 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.
+
+    FairEmail 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 FairEmail.  If not, see <http://www.gnu.org/licenses/>.
+
+    Copyright 2018-2019 by Marcel Bokhorst (M66B)
+*/
+
+import org.json.JSONException;
+import org.json.JSONObject;
+
+import java.io.Serializable;
+
+import androidx.annotation.NonNull;
+import androidx.room.Entity;
+import androidx.room.Index;
+import androidx.room.PrimaryKey;
+
+// https://developer.android.com/training/data-storage/room/defining-data
+
+@Entity(
+        tableName = EntityContact.TABLE_NAME,
+        foreignKeys = {
+        },
+        indices = {
+                @Index(value = {"email", "type"}, unique = true),
+                @Index(value = {"name", "type"}),
+        }
+)
+public class EntityContact implements Serializable {
+    static final String TABLE_NAME = "contact";
+
+    static final int TYPE_TO = 0;
+    static final int TYPE_FROM = 1;
+
+    @PrimaryKey(autoGenerate = true)
+    public Long id;
+    @NonNull
+    public int type;
+    @NonNull
+    public String email;
+    public String name;
+
+    public JSONObject toJSON() throws JSONException {
+        JSONObject json = new JSONObject();
+        json.put("id", id);
+        json.put("type", type);
+        json.put("email", email);
+        json.put("name", name);
+        return json;
+    }
+
+    public static EntityContact fromJSON(JSONObject json) throws JSONException {
+        EntityContact contact = new EntityContact();
+        // id
+        contact.type = json.getInt("type");
+        contact.email = json.getString("email");
+        if (json.has("name"))
+            contact.name = json.getString("name");
+        return contact;
+    }
+
+    @NonNull
+    @Override
+    public String toString() {
+        return (name == null ? email : name + " <" + email + ">");
+    }
+}