Add distance between two places

dacr · Jul 24, 2024 · 5bb830e · 5bb830e
1 parent a502767
commit 5bb830e
Show file tree

Hide file tree

Showing 2 changed files with 102 additions and 23 deletions.
diff --git a/modules/model/src/main/scala/fr/janalyse/sotohp/model/PhotoPlace.scala b/modules/model/src/main/scala/fr/janalyse/sotohp/model/PhotoPlace.scala
@@ -29,12 +29,14 @@ object DecimalDegrees {
   }
 
   extension (dd: LatitudeDecimalDegrees) {
-    @targetName("doubleValue_latitude")
     def doubleValue: Double = dd
+    def toRadians: Double   = dd.toRadians
   }
   extension (dd: LongitudeDecimalDegrees) {
     @targetName("doubleValue_longitude")
     def doubleValue: Double = dd
+    @targetName("doubleValue_toRadians")
+    def toRadians: Double   = dd.toRadians
   }
 
 }
@@ -106,15 +108,15 @@ case class PhotoPlace(
   latitude: LatitudeDecimalDegrees,
   longitude: LongitudeDecimalDegrees,
   altitude: Option[AltitudeMeanSeaLevel],
-  deducted: Boolean 
+  deducted: Boolean
 )
 
 object PhotoPlace {
   def apply(
     latitudeDMS: LatitudeDegreeMinuteSeconds,
     longitudeDMS: LongitudeDegreeMinuteSeconds,
-    altitudeMeanSeaLevel: Option[AltitudeMeanSeaLevel],
-    deducted: Boolean
+    altitudeMeanSeaLevel: Option[AltitudeMeanSeaLevel] = None,
+    deducted: Boolean = false
   ): PhotoPlace = {
     PhotoPlace(
       latitudeDMS.toDecimalDegrees,
@@ -123,4 +125,54 @@ object PhotoPlace {
       deducted
     )
   }
+
+  def fromDecimalDegrees(
+    latitudeDMS: LatitudeDecimalDegrees,
+    longitudeDMS: LongitudeDecimalDegrees,
+    altitudeMeanSeaLevel: Option[AltitudeMeanSeaLevel] = None,
+    deducted: Boolean = false
+  ): PhotoPlace = {
+    PhotoPlace(
+      latitudeDMS,
+      longitudeDMS,
+      altitudeMeanSeaLevel,
+      deducted
+    )
+  }
+
+  def fromLocationSpecs(
+    latitudeSpec: String,
+    longitudeSpec: String,
+    altitudeMeanSeaLevel: Option[AltitudeMeanSeaLevel] = None,
+    deducted: Boolean = false
+  ): Try[PhotoPlace] = {
+    for {
+      latitudeDMS  <- LatitudeDegreeMinuteSeconds.fromSpec(latitudeSpec)
+      longitudeDMS <- LongitudeDegreeMinuteSeconds.fromSpec(longitudeSpec)
+    } yield PhotoPlace(
+      latitudeDMS,
+      longitudeDMS,
+      altitudeMeanSeaLevel,
+      deducted
+    )
+  }
+
+  extension (from: PhotoPlace) {
+    def distanceTo(to: PhotoPlace): Double = {
+      val earthRadius    = 6371000d
+      val deltaLatitude  = to.latitude.toRadians - from.latitude.toRadians
+      val deltaLongitude = to.longitude.toRadians - from.longitude.toRadians
+
+      val a =
+        Math.sin(deltaLatitude / 2) * Math.sin(deltaLatitude / 2) +
+          Math.sin(deltaLongitude / 2) * Math.sin(deltaLongitude / 2) *
+          Math.cos(from.latitude.toRadians) *
+          Math.cos(to.latitude.toRadians)
+
+      val c = 2 * Math.atan2(Math.sqrt(a), Math.sqrt(1 - a));
+
+      earthRadius * c
+    }
+  }
+
 }
diff --git a/modules/model/src/test/scala/fr/janalyse/sotohp/model/PhotoPlaceSpec.scala b/modules/model/src/test/scala/fr/janalyse/sotohp/model/PhotoPlaceSpec.scala
@@ -4,7 +4,7 @@ import zio.*
 import zio.ZIO.*
 import zio.test.*
 import fr.janalyse.sotohp.model.DegreeMinuteSeconds.*
-import fr.janalyse.sotohp.model.DecimalDegrees.*
+import fr.janalyse.sotohp.model.DecimalDegrees.{LatitudeDecimalDegrees, *}
 
 import scala.util.{Success, Try}
 
@@ -19,7 +19,7 @@ object PhotoPlaceSpec extends ZIOSpecDefault {
     TestDataSet("from wikipedia decimal places 5 case", "0° 00′ 0.036″ N", 9.999999999999999e-6),
     TestDataSet("alternative representation 1", "3°58'24\" S", -3.9733333333333336d),
     TestDataSet("alternative representation 2", "03°58'24\" S", -3.9733333333333336d),
-    //TestDataSet("alternative representation 3", "-3°58'24\" S", -3.9733333333333336d), // TODO Check the meaning of negative values in DMS part
+    // TestDataSet("alternative representation 3", "-3°58'24\" S", -3.9733333333333336d), // TODO Check the meaning of negative values in DMS part
     TestDataSet("alternative representation 4", "3° 58'  24\"  S", -3.9733333333333336d),
     TestDataSet("alternative representation 5", "3° 58'  24''  S", -3.9733333333333336d),
     TestDataSet("alternative representation 6", "3° 58'  24″  S", -3.9733333333333336d),
@@ -34,28 +34,55 @@ object PhotoPlaceSpec extends ZIOSpecDefault {
   )
 
   override def spec =
-    suite("Degrees minutes seconds")(
-      suite("for latitude")(
-        for {
-          TestDataSet(testName, givenDMSSpec, expectedDegrees) <- latitudeTestDataset
-        } yield test(testName)(
+    suite("PhotoPlace Test Suite")(
+      suite("DegreesMinutesSeconds features")(
+        suite("should support various encoding for latitude")(
           for {
-            dms <- from(LatitudeDegreeMinuteSeconds.fromSpec(givenDMSSpec))
-          } yield assertTrue(
-            dms.toDecimalDegrees == LatitudeDecimalDegrees(expectedDegrees)
+            TestDataSet(testName, givenDMSSpec, expectedDegrees) <- latitudeTestDataset
+          } yield test(testName)(
+            for {
+              dms <- from(LatitudeDegreeMinuteSeconds.fromSpec(givenDMSSpec))
+            } yield assertTrue(
+              dms.toDecimalDegrees == LatitudeDecimalDegrees(expectedDegrees)
+            )
           )
-        )
-      ),
-      suite("for longitude")(
-        for {
-          TestDataSet(testName, givenDMSSpec, expectedDegrees) <- longitudeTestDataSet
-        } yield test(testName)(
+        ),
+        suite("should support various encoding for latitude")(
           for {
-            dms <- from(LongitudeDegreeMinuteSeconds.fromSpec(givenDMSSpec))
-          } yield assertTrue(
-            dms.toDecimalDegrees == LongitudeDecimalDegrees(expectedDegrees)
+            TestDataSet(testName, givenDMSSpec, expectedDegrees) <- longitudeTestDataSet
+          } yield test(testName)(
+            for {
+              dms <- from(LongitudeDegreeMinuteSeconds.fromSpec(givenDMSSpec))
+            } yield assertTrue(
+              dms.toDecimalDegrees == LongitudeDecimalDegrees(expectedDegrees)
+            )
           )
         )
+      ),
+      suite("Distance features")(
+        test("should return zero when the same place is given") {
+          val from = PhotoPlace.fromDecimalDegrees(LatitudeDecimalDegrees(0d), LongitudeDecimalDegrees(0d))
+          val to   = from
+          assertTrue(
+            from.distanceTo(to) == 0
+          )
+        },
+        test("should return the right distance between two places") {
+          ZIO.fromTry(
+            for {
+              paris <- PhotoPlace.fromLocationSpecs("48° 51' 52.9776'' N", "2° 20' 56.4504'' E")
+              brest <- PhotoPlace.fromLocationSpecs("48° 23' 23.9964'' N", "4° 29' 24.0000'' W")
+              dist1  = paris.distanceTo(brest)
+              dist2  = brest.distanceTo(paris)
+            } yield {
+              assertTrue(
+                dist1 == dist2,
+                dist1 < 506_000,
+                dist1 > 504_000
+              )
+            }
+          )
+        }
       )
     )
 }