core: stdcm: account for previous margins when checking for new ones

Signed-off-by: Eloi Charpentier <eloi.charpentier.42@gmail.com>

Author: eckter

core/src/main/kotlin/fr/sncf/osrd/stdcm/graph/EngineeringAllowanceManager.kt

@@ -216,6 +216,7 @@ class EngineeringAllowanceManager(private val graph: STDCMGraph) {
                 return ArrayList(res)
             }
             mutDelayNeeded += mutEdge.timeData.delayAddedToLastDeparture
+            mutDelayNeeded += mutEdge.engineeringAllowance?.extraDuration ?: 0.0
             mutEdge = mutEdge.previousNode.previousEdge!!
         }
     }

core/src/main/kotlin/fr/sncf/osrd/stdcm/graph/PostProcessingSimulation.kt

@@ -211,7 +211,7 @@ private fun initFixedPoints(
     }
     var prevEdgeLength = 0.meters
     for (edge in edges) {
-        val engineeringAllowanceLength = edge.engineeringAllowanceLength
+        val engineeringAllowanceLength = edge.engineeringAllowance?.length
         if (engineeringAllowanceLength != null) {
             val engineeringAllowanceStart = prevEdgeLength - engineeringAllowanceLength
             // Edges can have overlapping engineering allowance, only the last one is relevant.

core/src/main/kotlin/fr/sncf/osrd/stdcm/graph/STDCMEdge.kt

@@ -35,16 +35,24 @@ data class STDCMEdge(
     // How long it takes to go from the beginning to the end of the block, taking the
     // standard allowance into account
     val totalTime: Double,
-    // If this edges starts after the end of an engineering allowance, this contains its length, or
-    // null otherwise. Used for initial placement of fixed time points in postprocessing.
-    val engineeringAllowanceLength: Distance?,
+    // If this edges starts after the end of an engineering allowance, this contains
+    // some data like its length and extra time. Null if there's no engineering allowance
+    // ending here. Overrides any allowance spanning part of the range from previous edges.
+    val engineeringAllowance: EngineeringAllowanceData?,
 ) {
     val block = infraExplorer.getCurrentBlock()
 
     init {
         assert(!isNaN(timeData.earliestReachableTime)) { "STDCM edge starts at NaN time" }
     }
 
+    data class EngineeringAllowanceData(
+        /** How long is the allowance section. It always ends at the start of the current edge. */
+        val length: Distance,
+        /** How much extra time was added on this current allowance range. */
+        val extraDuration: Double,
+    )
+
     /** Returns the node at the end of this edge */
     fun getEdgeEnd(graph: STDCMGraph): STDCMNode {
         var newWaypointIndex = waypointIndex

core/src/main/kotlin/fr/sncf/osrd/stdcm/graph/STDCMEdgeBuilder.kt

@@ -161,13 +161,15 @@ internal constructor(
         var departureTimeShift = delayNeeded
         val needEngineeringAllowance =
             delayNeeded > prevNode.timeData.maxDepartureDelayingWithoutConflict
-        var allowanceLength: Distance? = null
+        var allowanceData: STDCMEdge.EngineeringAllowanceData? = null
         if (needEngineeringAllowance) {
             // We can't just shift the departure time, we need an engineering allowance
             // It's not computed yet, we just check that it's possible
-            allowanceLength =
+            val allowanceLength =
                 graph.allowanceManager.checkEngineeringAllowance(prevNode, actualStartTime)
                     ?: return null
+            val extraTime = delayNeeded - prevNode.timeData.maxDepartureDelayingWithoutConflict
+            allowanceData = STDCMEdge.EngineeringAllowanceData(allowanceLength, extraTime)
             // We still need to adapt the delay values
             departureTimeShift = prevNode.timeData.maxDepartureDelayingWithoutConflict
         } else {
@@ -217,7 +219,7 @@ internal constructor(
                 envelope!!.endSpeed,
                 Length(fromMeters(envelope!!.endPos)),
                 envelope!!.totalTime / standardAllowanceSpeedRatio,
-                allowanceLength,
+                allowanceData,
             )
         res = graph.backtrackingManager.backtrack(res!!, envelope!!)
         return if (res == null || graph.delayManager.isRunTimeTooLong(res)) null else res