refactor(simulator): Remove transform from SimResourceForwarder

This change removes the ability to transform the duration of a pull from
the SimResourceForwarder class. This ability is not used anymore, since
pushes are now done using a method instead of a command.

5 files changed, 34 insertions, 66 deletions

diff --git a/opendc-simulator/opendc-simulator-power/src/main/kotlin/org/opendc/simulator/power/SimPdu.kt b/opendc-simulator/opendc-simulator-power/src/main/kotlin/org/opendc/simulator/power/SimPdu.kt
index 947f6cb2..1a12a52a 100644
--- a/opendc-simulator/opendc-simulator-power/src/main/kotlin/org/opendc/simulator/power/SimPdu.kt
+++ b/opendc-simulator/opendc-simulator-power/src/main/kotlin/org/opendc/simulator/power/SimPdu.kt
@@ -42,7 +42,7 @@ public class SimPdu(
     private val switch = SimResourceSwitchMaxMin(interpreter)
 
     /**
-     * The [SimResourceTransformer] that represents the input of the PDU.
+     * The [SimResourceForwarder] that represents the input of the PDU.
      */
     private val forwarder = SimResourceForwarder()
 
diff --git a/opendc-simulator/opendc-simulator-power/src/main/kotlin/org/opendc/simulator/power/SimUps.kt b/opendc-simulator/opendc-simulator-power/src/main/kotlin/org/opendc/simulator/power/SimUps.kt
index 79c1b37d..9c7400ed 100644
--- a/opendc-simulator/opendc-simulator-power/src/main/kotlin/org/opendc/simulator/power/SimUps.kt
+++ b/opendc-simulator/opendc-simulator-power/src/main/kotlin/org/opendc/simulator/power/SimUps.kt
@@ -86,7 +86,7 @@ public class SimUps(
     /**
      * A UPS inlet.
      */
-    public inner class Inlet(private val forwarder: SimResourceTransformer) : SimPowerInlet(), AutoCloseable {
+    public inner class Inlet(private val forwarder: SimResourceForwarder) : SimPowerInlet(), AutoCloseable {
         override fun createConsumer(): SimResourceConsumer = forwarder
 
         /**
diff --git a/opendc-simulator/opendc-simulator-resources/src/main/kotlin/org/opendc/simulator/resources/SimResourceTransformer.kt b/opendc-simulator/opendc-simulator-resources/src/main/kotlin/org/opendc/simulator/resources/SimResourceForwarder.kt
index 76a3bdd7..0cd2bfc7 100644
--- a/opendc-simulator/opendc-simulator-resources/src/main/kotlin/org/opendc/simulator/resources/SimResourceTransformer.kt
+++ b/opendc-simulator/opendc-simulator-resources/src/main/kotlin/org/opendc/simulator/resources/SimResourceForwarder.kt
@@ -26,16 +26,11 @@ import org.opendc.simulator.resources.impl.SimResourceCountersImpl
 import java.time.Clock
 
 /**
- * A [SimResourceConsumer] and [SimResourceProvider] that transforms the resource commands emitted by the resource
- * commands to the resource provider.
+ * A class that acts as a [SimResourceConsumer] and [SimResourceProvider] at the same time.
  *
  * @param isCoupled A flag to indicate that the transformer will exit when the resource consumer exits.
- * @param transform The function to transform the received resource command.
  */
-public class SimResourceTransformer(
-    private val isCoupled: Boolean = false,
-    private val transform: (SimResourceContext, Long) -> Long
-) : SimResourceConsumer, SimResourceProvider, AutoCloseable {
+public class SimResourceForwarder(private val isCoupled: Boolean = false) : SimResourceConsumer, SimResourceProvider, AutoCloseable {
     /**
      * The delegate [SimResourceConsumer].
      */
@@ -49,25 +44,25 @@ public class SimResourceTransformer(
     /**
      * The exposed [SimResourceContext].
      */
-    private val ctx = object : SimResourceContext {
+    private val _ctx = object : SimResourceContext {
         override val clock: Clock
-            get() = _ctx!!.clock
+            get() = _innerCtx!!.clock
 
         override val capacity: Double
-            get() = _ctx?.capacity ?: 0.0
+            get() = _innerCtx?.capacity ?: 0.0
 
         override val demand: Double
-            get() = _ctx?.demand ?: 0.0
+            get() = _innerCtx?.demand ?: 0.0
 
         override val speed: Double
-            get() = _ctx?.speed ?: 0.0
+            get() = _innerCtx?.speed ?: 0.0
 
         override fun interrupt() {
-            _ctx?.interrupt()
+            _innerCtx?.interrupt()
         }
 
         override fun push(rate: Double) {
-            _ctx?.push(rate)
+            _innerCtx?.push(rate)
             _limit = rate
         }
 
@@ -75,9 +70,9 @@ public class SimResourceTransformer(
             val delegate = checkNotNull(delegate) { "Delegate not active" }
 
             if (isCoupled)
-                _ctx?.close()
+                _innerCtx?.close()
             else
-                _ctx?.push(0.0)
+                _innerCtx?.push(0.0)
 
             // Warning: resumption of the continuation might change the entire state of the forwarder. Make sure we
             // reset beforehand the existing state and check whether it has been updated afterwards
@@ -90,19 +85,19 @@ public class SimResourceTransformer(
     /**
      * The [SimResourceContext] in which the forwarder runs.
      */
-    private var _ctx: SimResourceContext? = null
+    private var _innerCtx: SimResourceContext? = null
 
     override val isActive: Boolean
         get() = delegate != null
 
     override val capacity: Double
-        get() = ctx.capacity
+        get() = _ctx.capacity
 
     override val speed: Double
-        get() = ctx.speed
+        get() = _ctx.speed
 
     override val demand: Double
-        get() = ctx.demand
+        get() = _ctx.demand
 
     override val counters: SimResourceCounters
         get() = _counters
@@ -118,27 +113,27 @@ public class SimResourceTransformer(
     }
 
     override fun interrupt() {
-        ctx.interrupt()
+        _ctx.interrupt()
     }
 
     override fun cancel() {
         val delegate = delegate
-        val ctx = _ctx
+        val ctx = _innerCtx
 
         if (delegate != null) {
             this.delegate = null
 
             if (ctx != null) {
-                delegate.onEvent(this.ctx, SimResourceEvent.Exit)
+                delegate.onEvent(this._ctx, SimResourceEvent.Exit)
             }
         }
     }
 
     override fun close() {
-        val ctx = _ctx
+        val ctx = _innerCtx
 
         if (ctx != null) {
-            this._ctx = null
+            this._innerCtx = null
             ctx.interrupt()
         }
     }
@@ -152,38 +147,34 @@ public class SimResourceTransformer(
 
         updateCounters(ctx, delta)
 
-        return if (delegate != null) {
-            transform(ctx, delegate.onNext(this.ctx, now, delta))
-        } else {
-            Long.MAX_VALUE
-        }
+        return delegate?.onNext(this._ctx, now, delta) ?: Long.MAX_VALUE
     }
 
     override fun onEvent(ctx: SimResourceContext, event: SimResourceEvent) {
         when (event) {
             SimResourceEvent.Start -> {
-                _ctx = ctx
+                _innerCtx = ctx
             }
             SimResourceEvent.Exit -> {
-                _ctx = null
+                _innerCtx = null
 
                 val delegate = delegate
                 if (delegate != null) {
                     reset()
-                    delegate.onEvent(this.ctx, SimResourceEvent.Exit)
+                    delegate.onEvent(this._ctx, SimResourceEvent.Exit)
                 }
             }
-            else -> delegate?.onEvent(this.ctx, event)
+            else -> delegate?.onEvent(this._ctx, event)
         }
     }
 
     override fun onFailure(ctx: SimResourceContext, cause: Throwable) {
-        _ctx = null
+        _innerCtx = null
 
         val delegate = delegate
         if (delegate != null) {
             reset()
-            delegate.onFailure(this.ctx, cause)
+            delegate.onFailure(this._ctx, cause)
         }
     }
 
@@ -192,7 +183,7 @@ public class SimResourceTransformer(
      */
     private fun start() {
         val delegate = delegate ?: return
-        delegate.onEvent(checkNotNull(_ctx), SimResourceEvent.Start)
+        delegate.onEvent(checkNotNull(_innerCtx), SimResourceEvent.Start)
 
         hasDelegateStarted = true
     }
@@ -227,12 +218,3 @@ public class SimResourceTransformer(
         counters.overcommit += (work - actualWork)
     }
 }
-
-/**
- * Constructs a [SimResourceTransformer] that forwards the received resource command with an identity transform.
- *
- * @param isCoupled A flag to indicate that the transformer will exit when the resource consumer exits.
- */
-public fun SimResourceForwarder(isCoupled: Boolean = false): SimResourceTransformer {
-    return SimResourceTransformer(isCoupled) { _, command -> command }
-}
diff --git a/opendc-simulator/opendc-simulator-resources/src/main/kotlin/org/opendc/simulator/resources/SimResourceSwitchExclusive.kt b/opendc-simulator/opendc-simulator-resources/src/main/kotlin/org/opendc/simulator/resources/SimResourceSwitchExclusive.kt
index 2be8ccb0..f1e004d2 100644
--- a/opendc-simulator/opendc-simulator-resources/src/main/kotlin/org/opendc/simulator/resources/SimResourceSwitchExclusive.kt
+++ b/opendc-simulator/opendc-simulator-resources/src/main/kotlin/org/opendc/simulator/resources/SimResourceSwitchExclusive.kt
@@ -37,7 +37,7 @@ public class SimResourceSwitchExclusive : SimResourceSwitch {
     private val _inputs = mutableSetOf<SimResourceProvider>()
     override val inputs: Set<SimResourceProvider>
         get() = _inputs
-    private val _availableInputs = ArrayDeque<SimResourceTransformer>()
+    private val _availableInputs = ArrayDeque<SimResourceForwarder>()
 
     override val counters: SimResourceCounters = object : SimResourceCounters {
         override val demand: Double
@@ -114,7 +114,7 @@ public class SimResourceSwitchExclusive : SimResourceSwitch {
     /**
      * An output of the resource switch.
      */
-    private inner class Output(private val forwarder: SimResourceTransformer) : SimResourceProvider by forwarder {
+    private inner class Output(private val forwarder: SimResourceForwarder) : SimResourceProvider by forwarder {
         /**
          * Close the output.
          */
diff --git a/opendc-simulator/opendc-simulator-resources/src/test/kotlin/org/opendc/simulator/resources/SimResourceTransformerTest.kt b/opendc-simulator/opendc-simulator-resources/src/test/kotlin/org/opendc/simulator/resources/SimResourceForwarderTest.kt
index d7d0924f..49e60f68 100644
--- a/opendc-simulator/opendc-simulator-resources/src/test/kotlin/org/opendc/simulator/resources/SimResourceTransformerTest.kt
+++ b/opendc-simulator/opendc-simulator-resources/src/test/kotlin/org/opendc/simulator/resources/SimResourceForwarderTest.kt
@@ -33,9 +33,9 @@ import org.opendc.simulator.resources.consumer.SimWorkConsumer
 import org.opendc.simulator.resources.impl.SimResourceInterpreterImpl
 
 /**
- * A test suite for the [SimResourceTransformer] class.
+ * A test suite for the [SimResourceForwarder] class.
  */
-internal class SimResourceTransformerTest {
+internal class SimResourceForwarderTest {
     @Test
     fun testCancelImmediately() = runBlockingSimulation {
         val forwarder = SimResourceForwarder()
@@ -199,20 +199,6 @@ internal class SimResourceTransformerTest {
     }
 
     @Test
-    fun testTransformExit() = runBlockingSimulation {
-        val forwarder = SimResourceTransformer { ctx, _ -> ctx.close(); Long.MAX_VALUE }
-        val scheduler = SimResourceInterpreterImpl(coroutineContext, clock)
-        val source = SimResourceSource(1.0, scheduler)
-
-        val consumer = spyk(SimWorkConsumer(2.0, 1.0))
-        source.startConsumer(forwarder)
-        forwarder.consume(consumer)
-
-        assertEquals(0, clock.millis())
-        verify(exactly = 1) { consumer.onNext(any(), any(), any()) }
-    }
-
-    @Test
     fun testCounters() = runBlockingSimulation {
         val forwarder = SimResourceForwarder()
         val scheduler = SimResourceInterpreterImpl(coroutineContext, clock)