implement state machine and transitions; extend base machine and add base alphabet

Author: svencc

libs/statemachine/src/main/java/com/recom/statemachine/BaseAlphabet.java

@@ -0,0 +1,13 @@
+package com.recom.statemachine;
+
+import lombok.NonNull;
+import lombok.RequiredArgsConstructor;
+
+@RequiredArgsConstructor
+abstract public class BaseAlphabet<MACHINE extends BaseStateMachine> {
+
+    @NonNull
+    protected final MACHINE machine;
+
+
+}

libs/statemachine/src/main/java/com/recom/statemachine/BaseStateMachine.java

@@ -1,31 +1,42 @@
 package com.recom.statemachine;
 
 import lombok.Getter;
+import lombok.Locked;
 import lombok.NonNull;
 import lombok.Setter;
 import org.springframework.lang.Nullable;
 
 import java.time.Duration;
 import java.time.Instant;
 
-abstract public class BaseStateMachine<STATES extends Enum, TRANSITIONS extends BaseTransition<? extends BaseStateMachine, STATES>, EVENT extends BaseFSMEvent> {
+abstract public class BaseStateMachine<
+        STATES extends Enum,
+        TRANSITIONS extends BaseTransition<? extends BaseStateMachine<STATES, TRANSITIONS, ALPHABET, EVENT>>,
+        ALPHABET extends BaseAlphabet<? extends BaseStateMachine<STATES, TRANSITIONS, ALPHABET, EVENT>>,
+        EVENT extends BaseFSMEvent
+        > {
 
     @Getter
     @Setter
     @Nullable
     protected STATES currentMachineState;
     protected TRANSITIONS transitions;
+    protected ALPHABET alphabet;
     @NonNull
     private Instant lastEvent = Instant.now();
 
     protected BaseStateMachine() {
         currentMachineState = null;
         transitions = initTransitions();
+        alphabet = initAlphabet();
     }
 
     @NonNull
     protected abstract TRANSITIONS initTransitions();
 
+    @NonNull
+    protected abstract ALPHABET initAlphabet();
+
     private boolean triggerReRun = false;
 
     public abstract void start();
@@ -48,6 +59,7 @@ protected void triggerReRun() {
         triggerReRun = true;
     }
 
+    @Locked
     public void nextEvent(@NonNull final EVENT event) throws IllegalStateException {
         do {
             triggerReRun = false;

libs/statemachine/src/main/java/com/recom/statemachine/BaseTransition.java

@@ -4,7 +4,7 @@
 import lombok.RequiredArgsConstructor;
 
 @RequiredArgsConstructor
-abstract public class BaseTransition<MACHINE extends BaseStateMachine, STATES extends Enum> {
+abstract public class BaseTransition<MACHINE extends BaseStateMachine> {
 
     protected final MACHINE machine;
 
@@ -13,4 +13,8 @@ protected IllegalStateException getFsmIsNotStarted() {
         return new IllegalStateException("FSM is not started");
     }
 
+    protected IllegalStateException exceptWithDefault() {
+        return new IllegalStateException("Unexpected value: " + machine.getCurrentMachineState());
+    }
+
 }

services/recom-backend/src/main/java/com/recom/statemachine/game/GameAlphabet.java

@@ -0,0 +1,41 @@
+package com.recom.statemachine.game;
+
+import com.recom.model.HeartbeatModel;
+import com.recom.statemachine.BaseAlphabet;
+import lombok.NonNull;
+
+class GameAlphabet extends BaseAlphabet<GameMachine> {
+
+    public GameAlphabet(@NonNull final GameMachine gameMachine) {
+        super(gameMachine);
+    }
+
+    public boolean map_is_not_ready_ISH(@NonNull final GameEvent event) {
+        return event instanceof HeartbeatModel heartbeat && machine.gameMapService.provideGameMap(heartbeat.getMapName()).isEmpty();
+    }
+
+    public boolean map_is_ready_ISH(@NonNull final GameEvent event) {
+        return event instanceof HeartbeatModel heartbeat && machine.gameMapService.provideGameMap(heartbeat.getMapName()).isPresent();
+    }
+
+    public boolean scan_sector_ISH(@NonNull final GameEvent event) {
+        return false;
+    }
+
+    public boolean map_is_scanned_completely_ISH(@NonNull final GameEvent event) {
+        return false;
+    }
+
+    public boolean request_map_meta_ISH(@NonNull final GameEvent event) {
+        return false;
+    }
+
+    public boolean map_meta_is_created_ISH(@NonNull final GameEvent event) {
+        return false;
+    }
+
+    public boolean map_meta_not_created_ISH(@NonNull final GameEvent event) {
+        return false;
+    }
+
+}

services/recom-backend/src/main/java/com/recom/statemachine/game/GameMachine.java

@@ -1,6 +1,5 @@
 package com.recom.statemachine.game;
 
-import com.recom.model.HeartbeatModel;
 import com.recom.service.map.GameMapService;
 import com.recom.service.messagebus.MessageBusService;
 import com.recom.statemachine.BaseStateMachine;
@@ -10,69 +9,88 @@
 import java.time.Duration;
 
 @RequiredArgsConstructor
-public class GameMachine extends BaseStateMachine<GameStates, GameTransitions, GameEvent> {
+public class GameMachine extends BaseStateMachine<GameStates, GameTransitions, GameAlphabet, GameEvent> {
 
     @NonNull
-    private final GameMapService gameMapService;
+    final GameMapService gameMapService;
     @NonNull
-    private final MessageBusService messageBusService;
+    final private MessageBusService messageBusService;
 
     @NonNull
     @Override
     protected GameTransitions initTransitions() {
         return new GameTransitions(this);
     }
 
+    @NonNull
+    @Override
+    protected GameAlphabet initAlphabet() {
+        return new GameAlphabet(this);
+    }
+
     @Override
     public void start() {
         currentMachineState = GameStates.CHECK_MAP;
+        transitions.start();
         trackEventTime();
     }
 
     @Override
     public void stop() {
-        currentMachineState = GameStates.STOPPED;
+        transitions.end();
         trackEventTime();
     }
 
     @Override
     protected void handleEvent(
             @NonNull final GameEvent event,
             @NonNull final Duration deltaTime
-
     ) throws IllegalStateException {
         switch (currentMachineState) {
             case CHECK_MAP:
-                if (event instanceof HeartbeatModel heartbeat) {
-                    if (gameMapService.provideGameMap(heartbeat.getMapName()).isPresent()) {
-                        transitions.map_is_ready();
-                        triggerReRun();
-                    } else {
-                        transitions.map_is_not_ready();
-                        triggerReRun();
-                    }
+                if (alphabet.map_is_not_ready_ISH(event)) {
+                    transitions.map_is_not_ready();
+                    triggerReRun();
+                } else if (alphabet.map_is_ready_ISH(event)) {
+                    transitions.map_is_ready();
+                    triggerReRun();
                 }
                 break;
             case SCAN_MAP:
+                if (alphabet.map_is_scanned_completely_ISH(event)) {
+                    transitions.map_is_scanned_completely();
+                    triggerReRun();
+                } else if (alphabet.scan_sector_ISH(event)) {
+                    transitions.scan_sector();
+                    triggerReRun();
+                } else if (alphabet.request_map_meta_ISH(event)) {
+                    transitions.request_map_meta();
+                    triggerReRun();
+                }
 
                 // 1. request map_meta_creation if not exists
                 // 2. wait for map_meta_creation in state
                 // 3. trigger map_meta_is_created
 
                 // messageBusService.sendMessage();
                 break;
-            case IN_GAME:
+            case REQUEST_MAP_META:
+                if (alphabet.map_meta_is_created_ISH(event)) {
+                    transitions.map_meta_is_created();
+                    triggerReRun();
+                } else if (alphabet.map_meta_not_created_ISH(event)) {
+                    transitions.map_meta_not_created();
+                    triggerReRun();
+                }
                 break;
+            case IN_GAME:
+                break; // nothing to do yet here
             case STOPPED:
-                // fsm is stopped
-                break;
+                throw new IllegalStateException("FSM is stopped");
             case null:
-                // fsm is not started
-                break;
+                throw new IllegalStateException("FSM is not started");
             default:
-                // unknown state
-                throw new IllegalStateException("Unexpected value: " + currentMachineState);
-                // break;
+                throw new IllegalStateException("Unknown state in FSM detected: " + currentMachineState);
         }
     }
 

services/recom-backend/src/main/java/com/recom/statemachine/game/GameMachine.puml

@@ -11,10 +11,10 @@ CHECK_MAP --> SCAN_MAP :map_is_not_ready
 CHECK_MAP --> IN_GAME :map_is_ready
 
 SCAN_MAP --> REQUEST_MAP_META :request_map_meta
-REQUEST_MAP_META --> SCAN_MAP :map_meta_created
+REQUEST_MAP_META --> SCAN_MAP :map_meta_is_created
 REQUEST_MAP_META --> REQUEST_MAP_META :map_meta_not_created
 SCAN_MAP --> SCAN_MAP :scan_sector
-SCAN_MAP --> IN_GAME :map_is_scanned
+SCAN_MAP --> IN_GAME :map_is_scanned_completely
 
 
 
@@ -33,7 +33,10 @@ __**ALPHABET**__
 | map_is_not_ready | ... |
 | create_map | ... |
 | scan_sector | ... |
-| map_is_scanned | ... |
+| map_is_scanned_completely | ... |
+| request_map_meta | ... |
+| map_meta_not_created | ... |
+| map_meta_is_created | ... |
 endlegend
 
 @enduml

services/recom-backend/src/main/java/com/recom/statemachine/game/GameStates.java

@@ -3,6 +3,7 @@
 public enum GameStates  {
 
     CHECK_MAP,
+    REQUEST_MAP_META,
     SCAN_MAP,
     IN_GAME,
     STOPPED