module: add estimated risk level calculation based on UVA light intensity

- thresholds from vendor, take with a grain of salt as these are estimations

tests/veml6070_test.py

@@ -90,6 +90,17 @@ class TestVeml6070(snapshottest.TestCase):
         self.assertEqual(veml.get_uva_light_intensity(), 0x0106 * (0.1/0.1125) * 0.05 / 4)
         self.assertMatchSnapshot(mockbus._log)
 
+    def test_get_estimated_risk_level(self):
+        mockbus = setup_mockbus(initial_read={
+            0x38+1: [0x01, 0x04],
+            0x38+0: [0x06, 0x01]
+        })
+        veml = veml6070.Veml6070()
+        intensity = veml.get_uva_light_intensity()
+        self.assertEqual(veml.get_estimated_risk_level(intensity), "low")
+        intensity = veml.get_uva_light_intensity()
+        self.assertEqual(veml.get_estimated_risk_level(intensity), "moderate")
+
     def test_get_refresh_time(self):
         mockbus = setup_mockbus()
         veml = veml6070.Veml6070(rset=veml6070.RSET_240K)

veml6070/veml6070.py

@@ -102,3 +102,19 @@ class Veml6070(object):
             INTEGRATIONTIME_4T: 4
         }
         return self.rset * RSET_TO_REFRESHTIME_SCALE * case_refresh_it[self.integration_time]
+
+    @staticmethod
+    def get_estimated_risk_level(intensity):
+        """
+        returns estimated risk level from comparing UVA light intensity value
+        in W/(m*m) as parameter, thresholds calculated from application notes
+        """
+        if intensity < 24.888:
+            return "low"
+        if intensity < 49.800:
+            return "moderate"
+        if intensity < 66.400:
+            return "high"
+        if intensity < 91.288:
+            return "very high"
+        return "extreme"