altoslib: Don't store computed telemetry fields

[fw/altos] / altoslib / AltosTelemetry.java

diff --git a/altoslib/AltosTelemetry.java b/altoslib/AltosTelemetry.java
index f830bf3582a0a452f24facbda8671e45019d642b..5600e7beb3f19b31620d8217d9e239d8d0eda054 100644 (file)
--- a/altoslib/AltosTelemetry.java
+++ b/altoslib/AltosTelemetry.java
@@ -25,12 +25,15 @@ import java.text.*;
  */
 
 public abstract class AltosTelemetry implements AltosStateUpdate {
+       int[]   bytes;
 
        /* All telemetry packets have these fields */
-       public int      tick;
-       public int      serial;
-       public int      rssi;
-       public int      status;
+       public int rssi() { return AltosConvert.telem_to_rssi(AltosLib.int8(bytes, bytes.length - 3)); }
+       public int status() { return AltosLib.uint8(bytes, bytes.length - 2); }
+
+       /* All telemetry packets report these fields in some form */
+       public abstract int serial();
+       public abstract int tick();
 
        /* Mark when we received the packet */
        long            received_time;
@@ -44,11 +47,11 @@ public abstract class AltosTelemetry implements AltosStateUpdate {
        }
 
        public void update_state(AltosState state) {
-               state.set_serial(serial);
+               state.set_serial(serial());
                if (state.state() == AltosLib.ao_flight_invalid)
                        state.set_state(AltosLib.ao_flight_startup);
-               state.set_tick(tick);
-               state.set_rssi(rssi, status);
+               state.set_tick(tick());
+               state.set_rssi(rssi(), status());
                state.set_received_time(received_time);
        }
 
@@ -88,12 +91,6 @@ public abstract class AltosTelemetry implements AltosStateUpdate {
                if (!cksum(bytes))
                        throw new ParseException(String.format("invalid line \"%s\"", hex), 0);
 
-               int     rssi = AltosLib.int8(bytes, bytes.length - 3) / 2 - 74;
-               int     status = AltosLib.uint8(bytes, bytes.length - 2);
-
-               if ((status & PKT_APPEND_STATUS_1_CRC_OK) == 0)
-                       throw new AltosCRCException(rssi);
-
                /* length, data ..., rssi, status, checksum -- 4 bytes extra */
                switch (bytes.length) {
                case AltosLib.ao_telemetry_standard_len + 4:
@@ -108,11 +105,6 @@ public abstract class AltosTelemetry implements AltosStateUpdate {
                default:
                        throw new ParseException(String.format("Invalid packet length %d", bytes.length), 0);
                }
-               if (telem != null) {
-                       telem.received_time = System.currentTimeMillis();
-                       telem.rssi = rssi;
-                       telem.status = status;
-               }
                return telem;
        }
 
@@ -139,6 +131,17 @@ public abstract class AltosTelemetry implements AltosStateUpdate {
                return height;
        }
 
+       public AltosTelemetry() {
+               this.received_time = System.currentTimeMillis();
+       }
+
+       public AltosTelemetry(int[] bytes) throws AltosCRCException {
+               this();
+               this.bytes = bytes;
+               if ((status() & PKT_APPEND_STATUS_1_CRC_OK) == 0)
+                       throw new AltosCRCException(rssi());
+       }
+
        public static AltosTelemetry parse(String line) throws ParseException, AltosCRCException {
                String[] word = line.split("\\s+");
                int i =0;
@@ -149,7 +152,7 @@ public abstract class AltosTelemetry implements AltosStateUpdate {
                        throw new AltosCRCException(AltosParse.parse_int(word[i++]));
                }
 
-               AltosTelemetry telem;
+               AltosTelemetry telem = null;
 
                if (word[i].equals("TELEM")) {
                        telem = parse_hex(word[i+1]);