NAV (ephemeris): SV flag exploitation (#333)

Signed-off-by: Guillaume W. Bres <[email protected]>

Author: gwbres

db/NAV/orbits.json

@@ -503,7 +503,7 @@
             "uraiNed0": "f64",
             "uraiNed1": "f64",
             "uraiEd": "f64",
-            "svHealth": "f64",
+            "health": "flag",
             "tgd": "f64",
             "uraiNed2": "f64",
             "iscL1Ca": "f64",
@@ -542,7 +542,7 @@
             "uraiNed0": "f64",
             "uraiNed1": "f64",
             "uraiEd": "f64",
-            "svHealth": "f64",
+            "health": "flag",
             "tgd": "f64",
             "uraiNed2": "f64",
             "iscL1Ca": "f64",
@@ -584,7 +584,7 @@
             "week": "u32",
             "spare2": "f64",
             "accuracy": "f64",
-            "satH1": "flag",
+            "health": "flag",
             "tgd1b1b3": "f64",
             "tgd2b2b3": "f64",
             "t_tm": "f64",
@@ -621,7 +621,7 @@
             "week": "u32",
             "spare2": "f64",
             "accuracy": "f64",
-            "satH1": "flag",
+            "health": "flag",
             "tgdb1b3": "f64",
             "tgdb2b3": "f64",
             "t_tm": "f64",
@@ -656,7 +656,7 @@
             "week": "u32",
             "spare2": "f64",
             "accuracy": "f64",
-            "satH1": "flag",
+            "health": "flag",
             "tgdb1b3": "f64",
             "tgdb2b3": "f64",
             "t_tm": "f64",

src/navigation/ephemeris/mod.rs

@@ -7,6 +7,14 @@ pub mod flags;
 
 use orbits::OrbitItem;
 
+use flags::{
+    bds::{BdsHealth, BdsSatH1},
+    gal::GalHealth,
+    geo::GeoHealth,
+    glonass::{GlonassHealth, GlonassHealth2},
+    gps::GpsQzssl1cHealth,
+};
+
 #[cfg(feature = "log")]
 use log::error;
 
@@ -76,6 +84,62 @@ impl Ephemeris {
         Some(Duration::from_seconds(tgd_s))
     }
 
+    /// Returns true if this [Ephemeris] declares attached SV as suitable for navigation.
+    pub fn sv_healthy(&self) -> bool {
+        let health = self.orbits.get("health");
+
+        if health.is_none() {
+            return false;
+        }
+
+        let health = health.unwrap();
+
+        if let Some(flag) = health.as_gps_qzss_l1l2l5_health_flag() {
+            flag.healthy()
+        } else if let Some(flag) = health.as_gps_qzss_l1c_health_flag() {
+            !flag.intersects(GpsQzssl1cHealth::UNHEALTHY)
+        } else if let Some(flag) = health.as_glonass_health_flag() {
+            // TODO: Status mask .. ?
+            if let Some(flag2) = self
+                .orbits
+                .get("health2")
+                .and_then(|item| Some(item.as_glonass_health2_flag().unwrap()))
+            {
+                !flag.intersects(GlonassHealth::UNHEALTHY)
+                    && flag2.intersects(GlonassHealth2::HEALTHY_ALMANAC)
+            } else {
+                !flag.intersects(GlonassHealth::UNHEALTHY)
+            }
+        } else if let Some(flag) = health.as_geo_health_flag() {
+            // TODO !
+            false
+        } else if let Some(flag) = health.as_bds_sat_h1_flag() {
+            !flag.intersects(BdsSatH1::UNHEALTHY)
+        } else if let Some(flag) = health.as_bds_health_flag() {
+            flag == BdsHealth::Healthy
+        } else {
+            false
+        }
+    }
+
+    /// Returns true if this [Ephemeris] declares this satellite as in testing mode. declared healthy (suitable
+    pub fn sv_in_testing(&self) -> bool {
+        let health = self.orbits.get("health");
+
+        if health.is_none() {
+            return false;
+        }
+
+        let health = health.unwrap();
+
+        // only exists for modern BDS at the moment
+        if let Some(flag) = health.as_bds_health_flag() {
+            flag == BdsHealth::UnhealthyTesting
+        } else {
+            false
+        }
+    }
+
     /// Returns glonass frequency channel, in case this is a Glonass [Ephemeris] message,
     /// with described channel.
     pub fn glonass_freq_channel(&self) -> Option<i8> {

src/navigation/ephemeris/orbits.rs

@@ -208,10 +208,21 @@ impl OrbitItem {
 
                                 Ok(OrbitItem::GlonassHealth(flags))
                             },
+                            (
+                                NavMessageType::LNAV | NavMessageType::D1 | NavMessageType::D2,
+                                Constellation::BeiDou,
+                            ) => {
+                                // BDS H1 flag
+                                let flags = BdsSatH1::from_bits(unsigned)
+                                    .ok_or(ParsingError::NavFlagsMapping)?;
+
+                                Ok(OrbitItem::BdsSatH1(flags))
+                            },
                             (
                                 NavMessageType::CNV1 | NavMessageType::CNV2 | NavMessageType::CNV3,
                                 Constellation::BeiDou,
                             ) => {
+                                // Modern BDS flag
                                 let flags = BdsHealth::from(unsigned);
 
                                 Ok(OrbitItem::BdsHealth(flags))
@@ -231,21 +242,6 @@ impl OrbitItem {
                             _ => Err(ParsingError::NavHealthFlagDefinition),
                         }
                     },
-                    "satH1" => {
-                        // BDS H1 flag
-                        match (msgtype, constellation) {
-                            (
-                                NavMessageType::LNAV | NavMessageType::D1 | NavMessageType::D2,
-                                Constellation::BeiDou,
-                            ) => {
-                                let flags = BdsSatH1::from_bits(unsigned)
-                                    .ok_or(ParsingError::NavFlagsMapping)?;
-
-                                Ok(OrbitItem::BdsSatH1(flags))
-                            },
-                            _ => Err(ParsingError::NavHealthFlagDefinition),
-                        }
-                    },
                     "source" => {
                         // complex signal source indication
                         match (msgtype, constellation) {

src/navigation/ephemeris/parsing.rs

@@ -393,7 +393,7 @@ mod test {
             ephemeris.get_orbit_f64("accuracy"),
             Some(0.200000000000e+01)
         );
-        assert!(ephemeris.get_orbit_f64("satH1").is_some());
+        assert!(ephemeris.get_orbit_f64("health").is_some());
 
         assert_eq!(
             ephemeris.get_orbit_f64("tgd1b1b3"),

src/navigation/parsing/mod.rs

@@ -290,7 +290,7 @@ mod test {
             //SPARE
             } else if k.eq("accuracy") {
                 assert_eq!(v.as_f64(), 0.200000000000e+01);
-            } else if k.eq("satH1") {
+            } else if k.eq("health") {
                 assert_eq!(v.as_f64(), 0.000000000000e+00);
             } else if k.eq("tgd1b1b3") {
                 assert_eq!(v.as_f64(), -0.599999994133e-09);