Implement get_next_days_timescale

2 files changed, 38 insertions, 17 deletions

diff --git a/iss/predictions.py b/iss/predictions.py
index fa4aeff..37e23e6 100644
--- a/iss/predictions.py
+++ b/iss/predictions.py
@@ -3,21 +3,35 @@ from skyfield.api import Topos, load
 TEL_AVIV = Topos('32.0853 N', '34.7817 E')
 ISS = "ISS (ZARYA)"
 
-def init_stations():
-    stations_url = 'http://celestrak.com/NORAD/elements/stations.txt'
-    return load.tle_file(stations_url)
 
-def get_predictions(location=TEL_AVIV, satellite_name=ISS):
-    satellites = init_stations()
-    by_name = {sat.name: sat for sat in satellites}
-    satellite = by_name[satellite_name]
+class Predictions(object):
 
-    ts = load.timescale()
-    t0 = ts.now()
-    t1 = ts.utc(2020, 9, 30)
+    def __init__(self, lat, lng, tz="UTC", satellite=ISS):
+        self.lat = lat
+        self.lng = lng
+        self.tz = tz
+        self.satellite = satellite
 
-    t, events = satellite.find_events(location, t0, t1, altitude_degrees=60.0)
-    for ti, event in zip(t, events):
-        name = ('rise above 30°', 'culminate', 'set below 30°')[event]
-        print(ti)
-        print(ti.utc_strftime('%Y %b %d %H:%M:%S'), name)
+    def init_stations(self):
+        stations_url = 'http://celestrak.com/NORAD/elements/stations.txt'
+        return load.tle_file(stations_url)
+
+    def get_next_days_timescale(self, days=10):
+        ts = load.timescale()
+        t0 = ts.now()
+        t1 = ts.ut1_jd(t0.ut1 + days)
+        return t0, t1
+
+    def get_predictions(self, location=TEL_AVIV, satellite_name=ISS):
+        satellites = self.init_stations()
+        by_name = {sat.name: sat for sat in satellites}
+        satellite = by_name[satellite_name]
+
+        t0, t1 = self.get_next_days_timescale()
+
+        t, events = satellite.find_events(location, t0, t1, altitude_degrees=30.0)
+        print(t)
+        print(events)
+        for ti, event in zip(t, events):
+            name = ('rise above 30°', 'culminate', 'set below 30°')[event]
+            print(ti.utc_strftime('%Y %b %d %H:%M:%S'), name)
diff --git a/iss/tests/test_predictions.py b/iss/tests/test_predictions.py
index 43dad05..541b2d8 100644
--- a/iss/tests/test_predictions.py
+++ b/iss/tests/test_predictions.py
@@ -1,2 +1,9 @@
-def test_foo():
-    assert 1 == 1
+from ..predictions import Predictions
+
+
+def test_get_timescales():
+    p = Predictions(lat=32.0853, lng=34.7817, tz="Asia/Jerusalem")
+    days = 5
+    t0, t1 = p.get_next_days_timescale(days=days)
+    delta = t1.ut1 - t0.ut1
+    assert delta == days