handle prefixes

src/main/kotlin/com/restapi/controllers/Entities.kt

@@ -851,11 +851,20 @@ object IncomingInventoryCtrl {
 
     fun getNextNum(ctx: Context) {
         val prefix = "MRN/"
+        val plantId = ctx.queryParam("plantId") ?: throw BadRequestResponse("plantId not sent")
+        val plant = database.find(Plant::class.java)
+            .where()
+            .eq("plantId", plantId)
+            .findOne() ?: throw BadRequestResponse("plant missing for $plantId")
+        val inventoryPrefix = plant.prefixes?.get("INBOUND") ?: prefix
+
         val cnt = (database.find(IncomingInventory::class.java)
+            .where()
+            .eq("unloadingPlantId", plantId)
             .findCount() + 1)
             .toString()
             .padStart(6, '0')
-        val seq = SequenceNumber(prefix + cnt)
+        val seq = SequenceNumber(inventoryPrefix + cnt)
         ctx.json(seq).status(HttpStatus.OK)
     }
 }