Implement IS_IMMEDIATE

This is an escape hatch for actions that initiate combat. They should not take any time, in order not to mess with fighting order.

edgehead/assets/text/Knights/locations/024_darg_tent/000_darg_tent.egb.txt

@@ -83,6 +83,8 @@ c.hasHappened(evDargLeftCrowdsource)
 
 COMMAND: Darg >> Attack
 
+IS_IMMEDIATE: $TRUE
+
 COMPLETE_SUCCESS_DESCRIPTION:
 [We] approach Darg's tent. Darg spots me and looks surprised at first, then amused.
 

edgehead/assets/text/Knights/locations/024_outlook/000_outlook.egb.txt

@@ -49,6 +49,8 @@ FOR_LOCATION: $outlook
 
 COMMAND: Hawkman >> Approach
 
+IS_IMMEDIATE: $TRUE
+
 INK:
 The hawkman gives me a condescending look.
 

edgehead/assets/text/Knights/locations/029_crowdsource/000_crowdsource.egb.txt

@@ -131,6 +131,8 @@ w.actionHasBeenPerformed('crowdsource_listen')
 
 COMMAND: Orcs >> Attack
 
+IS_IMMEDIATE: $TRUE
+
 COMPLETE_SUCCESS_DESCRIPTION:
 [We] step from behind the columns and approach the two orcs.
 

edgehead/assets/text/Knights/locations/034_conet/000_conet.egb.txt

@@ -77,6 +77,8 @@ FOR_LOCATION: $conet
 
 COMMAND: Kobold >> Attack
 
+IS_IMMEDIATE: $TRUE
+
 COMPLETE_SUCCESS_DESCRIPTION:
 [We] step out of hiding. The kobold stops turning the wheel, briefly surprised. But then he jumps to the side and picks a big black wrench from a brown bag on the floor.
 

edgehead/assets/text/Knights/locations/040_smithy/000_smithy.egb.txt

@@ -55,6 +55,8 @@ COMMAND: Jailer >> Attack
 
 FOR_LOCATION: $smithy
 
+IS_IMMEDIATE: $TRUE
+
 COMPLETE_SUCCESS_DESCRIPTION:
 I drop down next to Sarn. He looks surprised but there is no recognition in his eyes.
 

edgehead/assets/text/Knights/locations/097_goblin_skirmish/100_goblin_skirmish_main.egb.txt

@@ -36,6 +36,8 @@ ACTION: $goblin_camp_attack
 COMMAND: Goblins >> Attack
 FOR_LOCATION: $goblin_skirmish_main
 
+IS_IMMEDIATE: $TRUE
+
 COMPLETE_SUCCESS_DESCRIPTION:
 [[RULESET]]
 [[RULE]]

edgehead/lib/fractal_stories/action.dart

@@ -513,12 +513,21 @@ class Performance<T> {
     // Move world time to when the turn happens.
     output.time = turn.time;
 
+    // Mark actor busy after performing their action.
     if (action.isProactive) {
-      // Mark actor busy after performing their action.
-      final recoveringUntil =
-          turn.time.add(action.getRecoveryDuration(context, object));
-      output.updateActorById(
-          turn.actor.id, (b) => b.recoveringUntil = recoveringUntil);
+      final recovery = action.getRecoveryDuration(context, object);
+      // First, check whether the action took any time. Some actions, such
+      // as initiating an attack, are pro-active, but don't take any time.
+      // In order to preserve fighting order, we should not change
+      // the attacker's `recoveringUntil`. Thus, we check if recovery
+      // is in fact more than zero.
+      if (recovery > Duration.zero) {
+        // The action was proactive and did take some time. Update the actor's
+        // [Actor.recoveringUntil].
+        final recoveringUntil = turn.time.add(recovery);
+        output.updateActorById(
+            turn.actor.id, (b) => b.recoveringUntil = recoveringUntil);
+      }
     }
 
     // Perform any [Situation.onAfterAction]s.

edgehead/lib/fractal_stories/writer_action.dart

@@ -34,6 +34,24 @@ abstract class RoamingAction extends Action<Nothing> {
 
   @override
   final bool isImplicit = false;
+
+  /// Some roaming actions can be immediate. This means that they will not
+  /// affect the performer's [Actor.recoveringUntil].
+  ///
+  /// This is useful for things like initiating an attack, where we don't want
+  /// the player to go last just because she is "recovering" from performing
+  /// the "initiate attack" action.
+  bool get isImmediate;
+
+  /// [RoamingAction] overrides this method to accommodate [isImmediate].
+  @override
+  Duration getRecoveryDuration(ApplicabilityContext context, Nothing object) {
+    if (isImmediate) {
+      return Duration.zero;
+    }
+
+    return super.getRecoveryDuration(context, object);
+  }
 }
 
 /// This is a simple actions that, once taken, always succeed.
@@ -66,6 +84,9 @@ class SimpleAction extends RoamingAction {
   @override
   bool get isAggressive => false;
 
+  @override
+  bool get isImmediate => false;
+
   @override
   bool get rerollable => false;