Add ema calculation class, calculate an emo temperature, use the ema_temperature in auto_window dectection

tests/test_ema.py

@@ -0,0 +1,53 @@
+# pylint: disable=line-too-long
+""" Tests de EMA calculation"""
+from datetime import datetime, timedelta
+
+from homeassistant.core import HomeAssistant
+
+from custom_components.versatile_thermostat.ema import EstimatedMobileAverage
+
+from .commons import get_tz
+
+
+def test_ema_basics(hass: HomeAssistant):
+    """Test the EMA calculation with basic features"""
+
+    tz = get_tz(hass)  # pylint: disable=invalid-name
+    now: datetime = datetime.now(tz=tz)
+
+    the_ema = EstimatedMobileAverage(
+        "test",
+        # 5 minutes
+        300,
+        # Needed for time calculation
+        get_tz(hass),
+    )
+
+    assert the_ema
+
+    current_timestamp = now
+    # First initialization
+    assert the_ema.calculate_ema(20, current_timestamp) == 20
+
+    current_timestamp = current_timestamp + timedelta(minutes=1)
+    # One minute later, same temperature. EMA temperature should not have change
+    assert the_ema.calculate_ema(20, current_timestamp) == 20
+
+    # Too short measurement should be ignored
+    assert the_ema.calculate_ema(2000, current_timestamp) == 20
+
+    current_timestamp = current_timestamp + timedelta(seconds=4)
+    assert the_ema.calculate_ema(20, current_timestamp) == 20
+
+    # a new normal measurement 5 minutes later
+    current_timestamp = current_timestamp + timedelta(minutes=5)
+    ema = the_ema.calculate_ema(25, current_timestamp)
+    assert ema > 20
+    assert ema == 22.5
+
+    # a big change in a short time does have a limited effect
+    current_timestamp = current_timestamp + timedelta(seconds=5)
+    ema = the_ema.calculate_ema(30, current_timestamp)
+    assert ema > 22.5
+    assert ema < 23
+    assert ema == 22.6