Xiaomi: Add sleep stages parser

From Alice

app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/devices/xiaomi/activity/XiaomiActivityFileId.java

@@ -192,6 +192,7 @@ public class XiaomiActivityFileId implements Comparable<XiaomiActivityFileId> {
     public enum Subtype {
         UNKNOWN(Type.UNKNOWN, -1),
         ACTIVITY_DAILY(Type.ACTIVITY, 0x00),
+        ACTIVITY_SLEEP_STAGES(Type.ACTIVITY, 0x03),
         ACTIVITY_SLEEP(Type.ACTIVITY, 0x08),
         SPORTS_OUTDOOR_RUNNING(Type.SPORTS, 0x01),
         SPORTS_FREESTYLE(Type.SPORTS, 0x08),

app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/devices/xiaomi/activity/XiaomiActivityParser.java

@@ -34,6 +34,7 @@ import nodomain.freeyourgadget.gadgetbridge.service.devices.xiaomi.XiaomiSupport
 import nodomain.freeyourgadget.gadgetbridge.service.devices.xiaomi.activity.impl.DailyDetailsParser;
 import nodomain.freeyourgadget.gadgetbridge.service.devices.xiaomi.activity.impl.DailySummaryParser;
 import nodomain.freeyourgadget.gadgetbridge.service.devices.xiaomi.activity.impl.SleepDetailsParser;
+import nodomain.freeyourgadget.gadgetbridge.service.devices.xiaomi.activity.impl.SleepStagesParser;
 import nodomain.freeyourgadget.gadgetbridge.service.devices.xiaomi.activity.impl.WorkoutGpsParser;
 import nodomain.freeyourgadget.gadgetbridge.service.devices.xiaomi.activity.impl.WorkoutSummaryParser;
 
@@ -95,6 +96,12 @@ public abstract class XiaomiActivityParser {
                     return new DailySummaryParser();
                 }
 
+                break;
+            case ACTIVITY_SLEEP_STAGES:
+                if (fileId.getDetailType() == XiaomiActivityFileId.DetailType.DETAILS) {
+                    return new SleepStagesParser();
+                }
+
                 break;
             case ACTIVITY_SLEEP:
                 if (fileId.getDetailType() == XiaomiActivityFileId.DetailType.DETAILS) {

app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/devices/xiaomi/activity/impl/SleepStagesParser.java

@@ -0,0 +1,80 @@
+/*  Copyright (C) 2023 Alice, José Rebelo
+
+    This file is part of Gadgetbridge.
+
+    Gadgetbridge is free software: you can redistribute it and/or modify
+    it under the terms of the GNU Affero General Public License as published
+    by the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    Gadgetbridge 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 Affero General Public License for more details.
+
+    You should have received a copy of the GNU Affero General Public License
+    along with this program.  If not, see <http://www.gnu.org/licenses/>. */
+package nodomain.freeyourgadget.gadgetbridge.service.devices.xiaomi.activity.impl;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import java.nio.ByteBuffer;
+import java.nio.ByteOrder;
+
+import nodomain.freeyourgadget.gadgetbridge.service.devices.xiaomi.XiaomiSupport;
+import nodomain.freeyourgadget.gadgetbridge.service.devices.xiaomi.activity.XiaomiActivityFileId;
+import nodomain.freeyourgadget.gadgetbridge.service.devices.xiaomi.activity.XiaomiActivityParser;
+
+public class SleepStagesParser extends XiaomiActivityParser {
+    private static final Logger LOG = LoggerFactory.getLogger(SleepStagesParser.class);
+
+    @Override
+    public boolean parse(final XiaomiSupport support, final XiaomiActivityFileId fileId, final byte[] bytes) {
+        if (fileId.getVersion() != 2) {
+            LOG.warn("Unknown sleep stages version {}", fileId.getVersion());
+            return false;
+        }
+
+        final ByteBuffer buf = ByteBuffer.wrap(bytes).order(ByteOrder.LITTLE_ENDIAN);
+
+        // over 4 days
+        // first 2 bytes: always FF FF
+        // bytes 3,4 small-medium
+        // byte 5 ???
+        // byte 6,7 small
+        final byte[] unk1 = new byte[7];
+        buf.get(unk1);
+
+        // total sleep duration in minutes
+        final short sleepDuration = buf.getShort();
+        // timestamp when watch counts "real" sleep start, might be later than first phase change
+        final int bedTime = buf.getInt();
+        // timestamp when sleep ended (have not observed, but may also be earlier than last phase?)
+        final int wakeUpTime = buf.getInt();
+
+        // byte 8 medium
+        // bytes 9,10 look like a short
+        final byte[] unk2 = new byte[3];
+        buf.get(unk2);
+
+        // sum of all "real" deep sleep durations
+        final short deepSleepDuration = buf.getShort();
+        // sum of all "real" light sleep durations
+        final short lightSleepDuration = buf.getShort();
+        // sum of all "real" REM durations
+        final short REMDuration = buf.getShort();
+        // sum of all "real" awake durations
+        final short wakeDuration = buf.getShort();
+
+        // byte 11 small-medium
+        final byte unk3 = buf.get();
+        while (buf.position() < buf.limit()) {
+            // when the change to the phase occurs
+            final int time = buf.getInt();
+            // what phase state changed to
+            final byte sleepPhase = buf.get();
+        }
+        return true;
+    }
+}