refactor!: consistently separate ShareDataOps from NeighborValuesOps

alchemist-incarnation-scafi3/src/test/resources/it/unibo/scafi/test/inline/load-from-scala-inline.yml

@@ -12,17 +12,17 @@ _pool: &program
         package it.unibo.scafi.test
 
         import it.unibo.scafi.alchemist.device.sensors.AlchemistEnvironmentVariables
-        import it.unibo.scafi.language.AggregateFoundation
         import it.unibo.scafi.language.fc.syntax.FieldCalculusSyntax
-        import it.unibo.scafi.libraries.FieldCalculusLibrary.share
-        import it.unibo.scafi.sensors.DistanceSensor
-        import it.unibo.scafi.sensors.DistanceSensor.senseDistance
+        import it.unibo.scafi.language.xc.calculus.ExchangeCalculus
         import it.unibo.scafi.libraries.All
         import it.unibo.scafi.libraries.All.given
+        import it.unibo.scafi.libraries.FieldCalculusLibrary.share
         import it.unibo.scafi.message.Codables.given
+        import it.unibo.scafi.sensors.DistanceSensor
+        import it.unibo.scafi.sensors.DistanceSensor.senseDistance
 
         object GradientInlined:
-          type Lang = AggregateFoundation { type DeviceId = Int } & FieldCalculusSyntax & DistanceSensor[Double] &
+          type Lang = ExchangeCalculus { type DeviceId = Int } & FieldCalculusSyntax & DistanceSensor[Double] &
           AlchemistEnvironmentVariables
 
           def gradientInlined(using Lang): Double =

alchemist-incarnation-scafi3/src/test/scala/it/unibo/scafi/test/Gradient.scala

@@ -1,8 +1,8 @@
 package it.unibo.scafi.test
 
 import it.unibo.scafi.alchemist.device.sensors.AlchemistEnvironmentVariables
-import it.unibo.scafi.language.AggregateFoundation
 import it.unibo.scafi.language.fc.syntax.FieldCalculusSyntax
+import it.unibo.scafi.language.xc.calculus.ExchangeCalculus
 import it.unibo.scafi.libraries.All
 import it.unibo.scafi.libraries.All.given
 import it.unibo.scafi.libraries.FieldCalculusLibrary.share
@@ -11,7 +11,7 @@ import it.unibo.scafi.sensors.DistanceSensor
 import it.unibo.scafi.sensors.DistanceSensor.senseDistance
 
 object Gradient:
-  type Lang = AggregateFoundation { type DeviceId = Int } & FieldCalculusSyntax & DistanceSensor[Double] &
+  type Lang = ExchangeCalculus { type DeviceId = Int } & FieldCalculusSyntax & DistanceSensor[Double] &
     AlchemistEnvironmentVariables
 
   def gradient(using Lang): Double =

scafi3-core/src/main/scala/it/unibo/scafi/language/AggregateFoundation.scala

@@ -1,7 +1,6 @@
 package it.unibo.scafi.language
 
 import it.unibo.scafi.collections.SafeIterable
-import it.unibo.scafi.utils.SharedDataOps
 
 import cats.Applicative
 

scafi3-core/src/main/scala/it/unibo/scafi/utils/SharedDataOps.scala → scafi3-core/src/main/scala/it/unibo/scafi/language/SharedDataOps.scala

@@ -1,4 +1,4 @@
-package it.unibo.scafi.utils
+package it.unibo.scafi.language
 
 import it.unibo.scafi.collections.SafeIterable
 
@@ -22,7 +22,3 @@ trait SharedDataOps[F[A] <: SafeIterable[A]]:
      *   the value of the "self" node
      */
     def onlySelf: A
-
-    def mapValues[B](f: A => B): F[B]
-
-    def alignedMap[B, C](other: F[B])(f: (A, B) => C): F[C]

scafi3-core/src/main/scala/it/unibo/scafi/language/xc/FieldBasedSharedData.scala

@@ -1,11 +1,8 @@
 package it.unibo.scafi.language.xc
 
-import scala.collection.MapView
-
 import it.unibo.scafi.collections.SafeIterable
-import it.unibo.scafi.language.ShareDataOps
+import it.unibo.scafi.language.SharedDataOps
 import it.unibo.scafi.language.xc.calculus.ExchangeCalculus
-import it.unibo.scafi.utils.SharedDataOps
 
 import cats.Applicative
 
@@ -14,34 +11,35 @@ import cats.Applicative
  */
 trait FieldBasedSharedData:
   this: ExchangeCalculus =>
-  override type SharedData[T] = Field[T]
+  override type SharedData[Value] = Field[Value]
 
   /**
    * A Field (NValue in https://doi.org/10.1016/j.jss.2024.111976) is a mapping from device ids to values of type T. For
    * devices not aligned with the current device, the default value is used.
-   * @param default
+   * @param defaultValue
    *   the default value for unaligned devices
    * @param neighborValues
    *   the values for all devices, aligned and unaligned
    * @tparam Value
    *   the type of the values
    */
   protected case class Field[+Value](
-      default: Value,
-      neighborValues: Map[DeviceId, Value] = Map.empty,
+      private[xc] val defaultValue: Value,
+      private[xc] val neighborValues: Map[DeviceId, Value] = Map.empty,
   ) extends SafeIterable[Value]:
 
     /**
      * @return
      *   a filtered view of the [[SharedData]] data that only contains the values for aligned devices
      */
     def alignedValues: Map[DeviceId, Value] =
-      if neighborValues.isEmpty then Map(localId -> default) // self is always aligned, even if there are no neighbors
+      if neighborValues.isEmpty then
+        Map(localId -> defaultValue) // self is always aligned, even if there are no neighbors
       else if alignedDevices.size == neighborValues.size then
         neighborValues // all devices are aligned, there is no need to filter
       else
         alignedDevices
-          .map(id => id -> neighborValues.getOrElse(id, default))
+          .map(id => id -> neighborValues.getOrElse(id, defaultValue))
           .toMap // in all other cases, I need to filter based on the aligned devices
 
     /**
@@ -50,12 +48,12 @@ trait FieldBasedSharedData:
      * @return
      *   the value for the given device id, or the default value if the device is not aligned
      */
-    def apply(id: DeviceId): Value = alignedValues.getOrElse(id, default)
+    def apply(id: DeviceId): Value = alignedValues.getOrElse(id, defaultValue)
 
     override def iterator: Iterator[Value] = alignedDevices
-      .map(id => neighborValues.getOrElse(id, default))
+      .map(id => neighborValues.getOrElse(id, defaultValue))
       .iterator
-    override def toString: String = s"Field($default, $neighborValues)"
+    override def toString: String = s"Field($defaultValue, $neighborValues)"
   end Field
 
   /**
@@ -64,52 +62,52 @@ trait FieldBasedSharedData:
    */
   protected def alignedDevices: Iterable[DeviceId]
 
-  override given fieldOps: ShareDataOps[SharedData, DeviceId] = new ShareDataOps[SharedData, DeviceId]:
-    extension [T](nv: Field[T])
-      override def default: T = nv.default
-      override def values: MapView[DeviceId, T] = nv.alignedValues.view
-      override def set(id: DeviceId, value: T): SharedData[T] = Field[T](
-        nv.default,
-        nv.neighborValues + (id -> value),
-      )
+  override given neighborValuesOps: NeighborValuesOps[Field, DeviceId] =
+    new NeighborValuesOps[Field, DeviceId]:
+      extension [A](a: Field[A])
+        override def mapValues[B](f: A => B): SharedData[B] = Field[B](
+          f(a.default),
+          a.neighborValues.view.mapValues(f).toMap,
+        )
+
+        override def alignedMap[B, C](other: SharedData[B])(f: (A, B) => C): SharedData[C] =
+          require(
+            a.neighborValues.keySet.diff(other.neighborValues.keySet).isEmpty,
+            s"Cannot alignedMap fields with different aligned devices: ${a.neighborValues.keySet} vs ${other.neighborValues.keySet}",
+          )
+          Field[C](
+            f(a.default, other.default),
+            a.neighborValues.view.map { case (id, value) => id -> f(value, other(id)) }.toMap,
+          )
+        override def apply(id: DeviceId): A = a.neighborValues.getOrElse(id, a.defaultValue)
+        private[xc] override def set(id: DeviceId, value: A): SharedData[A] = Field[A](
+          a.default,
+          a.neighborValues + (id -> value),
+        )
+        override def default: A = a.defaultValue
+        override def values: Map[DeviceId, A] = a.neighborValues
+        override def get(id: DeviceId): Option[A] = a.neighborValues.get(id)
+      end extension
 
-  override given sharedDataApplicative: Applicative[SharedData] = new Applicative[SharedData]:
+  override given sharedDataApplicative: Applicative[Field] = new Applicative[Field]:
     override def pure[A](x: A): Field[A] = Field(x, Map.empty)
 
     override def ap[A, B](ff: Field[A => B])(fa: Field[A]): Field[B] = Field(
-      ff.default(fa.default),
+      ff.defaultValue(fa.defaultValue),
       (ff.neighborValues.keySet ++ fa.neighborValues.keySet)
         .map(deviceId => deviceId -> ff(deviceId)(fa(deviceId)))
         .toMap,
     )
 
     override def map[A, B](fa: Field[A])(f: A => B): Field[B] = Field[B](
-      f(fa.default),
+      f(fa.defaultValue),
       fa.neighborValues.view.mapValues(f).toMap,
     )
 
-  override given sharedDataOps: SharedDataOps[SharedData] = new SharedDataOps[SharedData]:
-    extension [A](a: Field[A])
-      override def withoutSelf: SafeIterable[A] =
-        val filtered = a.alignedValues.view.filterKeys(_ != localId).values
-        SafeIterable(filtered)
-      override def onlySelf: A = a(localId)
-
-      override def mapValues[B](f: A => B): SharedData[B] = Field[B](
-        f(a.default),
-        a.neighborValues.view.mapValues(f).toMap,
-      )
-
-      override def alignedMap[B, C](other: SharedData[B])(f: (A, B) => C): SharedData[C] =
-        require(
-          a.neighborValues.keySet.diff(other.neighborValues.keySet).isEmpty,
-          s"Cannot alignedMap fields with different aligned devices: ${a.neighborValues.keySet} vs ${other.neighborValues.keySet}",
-        )
-        Field[C](
-          f(a.default, other.default),
-          a.neighborValues.view.map { case (id, value) => id -> f(value, other(id)) }.toMap,
-        )
-    end extension
+  override given sharedDataOps: SharedDataOps[Field] = new SharedDataOps[Field]:
+    extension [A](field: Field[A])
+      override def withoutSelf: SafeIterable[A] = SafeIterable(field.neighborValues.values)
+      override def onlySelf: A = field(localId)
 
   override given convert[T]: Conversion[T, SharedData[T]] = Field[T](_)
 

scafi3-core/src/main/scala/it/unibo/scafi/language/xc/NeighborValuesOps.scala

@@ -0,0 +1,75 @@
+package it.unibo.scafi.language.xc
+
+/**
+ * This trait defines the operations that can be performed on NValues.
+ * @tparam SharedData
+ *   the type of the SharedData.
+ * @tparam DeviceId
+ *   the type of the device id
+ */
+trait NeighborValuesOps[SharedData[_], DeviceId]:
+  extension [A](sharedData: SharedData[A])
+    /**
+     * Returns the default value for unaligned devices.
+     * @return
+     *   the default value.
+     */
+    def default: A
+
+    /**
+     * Maps the values of the SharedData using the provided function.
+     * @param f
+     *   the mapping function.
+     * @tparam B
+     *   the type of the mapped values.
+     * @return
+     *   a new SharedData with the mapped values.
+     */
+    def mapValues[B](f: A => B): SharedData[B]
+
+    /**
+     * Maps the values of this SharedData and another SharedData using the provided function. Assumes both SharedData
+     * are aligned, i.e., they contain values for the same set of device ids.
+     * @param other
+     *   the other SharedData to map with.
+     * @param f
+     *   the mapping function that takes a value from this SharedData and a value from the other SharedData.
+     * @tparam B
+     *   the type of the values in the other SharedData.
+     * @tparam C
+     *   the type of the mapped values.
+     * @return
+     *   a new SharedData with the mapped values.
+     */
+    def alignedMap[B, C](other: SharedData[B])(f: (A, B) => C): SharedData[C]
+
+    /**
+     * Retrieves the value associated with the given device id. If the device is unaligned, returns the default value.
+     * @param id
+     *   the device id.
+     * @return
+     *   the value associated with the device id.
+     * @throws NoSuchElementException
+     *   if the device id is unaligned.
+     */
+    def apply(id: DeviceId): A
+
+    /**
+     * Retrieves the value associated with the given device id, if the device is aligned.
+     * @param id
+     *   the device id.
+     * @return
+     *   an option containing the value if the device is aligned, or None if it is unaligned.
+     */
+    def get(id: DeviceId): Option[A]
+
+    /**
+     * Retrieves a map of all device ids to their associated values.
+     * @return
+     *   a map of device ids to values.
+     */
+    def values: Map[DeviceId, A]
+
+    private[xc] def set(id: DeviceId, value: A): SharedData[A]
+  end extension
+end NeighborValuesOps

scafi3-core/src/main/scala/it/unibo/scafi/language/xc/calculus/ExchangeCalculus.scala

@@ -1,6 +1,7 @@
 package it.unibo.scafi.language.xc.calculus
 
-import it.unibo.scafi.language.{ AggregateFoundation, ShareDataOps }
+import it.unibo.scafi.language.AggregateFoundation
+import it.unibo.scafi.language.xc.NeighborValuesOps
 import it.unibo.scafi.message.CodableFromTo
 
 /**
@@ -14,9 +15,9 @@ trait ExchangeCalculus extends AggregateFoundation:
    * @return
    *   an instance of [[SharedDataOps]]
    * @see
-   *   [[ShareDataOps]]
+   *   [[NeighborValuesOps]]
    */
-  given fieldOps: ShareDataOps[SharedData, DeviceId] = scala.compiletime.deferred
+  given neighborValuesOps: NeighborValuesOps[SharedData, DeviceId] = scala.compiletime.deferred
 
   /**
    * Local values can be considered [[SharedData]].