fix: multiple crashes, threading problem and scoping inconsistency within functions

src/main/interpreter/Interpreter.java

@@ -2,6 +2,7 @@
 
 import interpreter.antlr.MineScriptLexer;
 import interpreter.antlr.MineScriptParser;
+import interpreter.exceptions.ThreadInterruptedException;
 import interpreter.types.MSMessageType;
 import minescript.network.TurtleCommands;
 import net.minecraft.server.MinecraftServer;
@@ -27,6 +28,7 @@ public Interpreter(String program, MinecraftServer server, ServerWorld world, Bl
 
     @Override
     public void run() {
+        System.out.println("Thread started");
         try {
             // Create a CharStream that reads from standard input
             CharStream input = CharStreams.fromString(program + System.lineSeparator());
@@ -43,8 +45,11 @@ public void run() {
             ParseTree tree = parser.program(); // Begin parsing at init rule
             Visitor visitor = new Visitor(server, world, turtlePos, new SymbolTable());
             visitor.visit(tree);
+        } catch (ThreadInterruptedException e) {
+            System.out.println(e.getMessage());
         } catch (Exception e) {
             TurtleCommands.print(server, e.getMessage(), MSMessageType.ERROR);
         }
+        System.out.println("Thread finished");
     }
 }

src/main/interpreter/SymbolTable.java

@@ -35,12 +35,13 @@ public void enterSymbol(String name, MSType value) {
         Symbol newSymbol = new Symbol(name, value);
         checkRestrictedKeyWords(newSymbol);
 
-        /*If the variable is already in the current scope, update it*/
-        if (isVarInNewScope(name)) {
-            Symbol oldSymbol = hashMap.get(getPrefixName(name));
+        /*If a prefixed version of the variable already exists, update it*/
+        String shadowedSymbolName = getShadowedSymbolName(name);
+        if (shadowedSymbolName != null) {
+            Symbol oldSymbol = hashMap.get(shadowedSymbolName);
             delete(oldSymbol.name);
-            Symbol prefixSymbol = new Symbol(oldSymbol.name, value);
-            add(prefixSymbol);
+            Symbol newShadowedSymbol = new Symbol(oldSymbol.name, value);
+            add(newShadowedSymbol);
             return;
         }
 
@@ -77,8 +78,9 @@ else if (symbol.name.equals(funcName.name())){
      * @return symbol from the hash table
      */
     public Symbol retrieveSymbol(String name) {
-        if (isVarInNewScope(name)) {
-            return hashMap.get(getPrefixName(name));
+        String shadowedSymbolName = getShadowedSymbolName(name);
+        if (shadowedSymbolName != null) {
+            return hashMap.get(shadowedSymbolName);
         } else if (hashMap.containsKey(name)) {
             return hashMap.get(name);
         } else {
@@ -108,20 +110,23 @@ private void add(Symbol symbol) {
         hashMap.put(symbol.name, symbol);
     }
 
-    /**
-     * @param name name of the variable
-     * @return true if the variable is in the current scope
-     */
-    private boolean isVarInNewScope(String name) {
-        return scopeStack.peek().stream().anyMatch(s -> s.endsWith("." + name));
-    }
-
     /**
      * @param name id of the variable
-     * @return prefix of the variable
+     * @return name of the symbol if a prefixed version of it exists in any of the scopes, otherwise null
      */
-    private String getPrefixName(String name) {
-        return scopeStack.peek().stream().filter(s -> s.contains("." + name)).findFirst().orElseThrow();
+    private String getShadowedSymbolName(String name) {
+        if (scopeStack.empty()) return null;
+
+        ArrayList<String> currentScope = scopeStack.peek();
+        if (currentScope.stream().anyMatch(s -> s.endsWith("." + name))) {
+            return currentScope.stream().filter(s -> s.endsWith("." + name)).findFirst().orElseThrow();
+        }
+        else {
+            scopeStack.pop();
+            String res = getShadowedSymbolName(name);
+            scopeStack.push(currentScope);
+            return res;
+        }
     }
 
     private record Symbol(String name, MSType value) {

src/main/interpreter/Visitor.java

@@ -3,6 +3,7 @@
 import interpreter.antlr.MineScriptBaseVisitor;
 import interpreter.antlr.MineScriptParser;
 import interpreter.exceptions.SymbolNotFoundException;
+import interpreter.exceptions.ThreadInterruptedException;
 import interpreter.types.*;
 import minescript.network.TurtleCommands;
 import net.minecraft.block.Block;
@@ -446,7 +447,7 @@ public MSType visitFuncCall(MineScriptParser.FuncCallContext ctx) {
                     throw new RuntimeException(getFuncCallErrorMessage(id, new int[]{1}, "number", actualParams));
                 }
 
-                retVal = new MSNumber((int) Math.round(Math.sqrt(n.getValue())));
+                retVal = new MSNumber((int) Math.floor(Math.sqrt(n.getValue())));
             }
             case "Random" -> {
                 /*If no parameter is used returns a random unbounded int*/
@@ -477,21 +478,21 @@ public MSType visitFuncCall(MineScriptParser.FuncCallContext ctx) {
 
                 this.turtleDelay = 200 - n.getValue() * 20;
             }
-            case "GetXPosition" -> {
+            case "GetXCoordinate" -> {
                 if (actualParams.size() != 0) {
                     throw new RuntimeException(getFuncCallErrorMessage(id, new int[]{0}, "", actualParams));
                 }
 
                 retVal = new MSNumber(pos.getX());
             }
-            case "GetYPosition" -> {
+            case "GetYCoordinate" -> {
                 if (actualParams.size() != 0) {
                     throw new RuntimeException(getFuncCallErrorMessage(id, new int[]{0}, "", actualParams));
                 }
 
                 retVal = new MSNumber(pos.getY());
             }
-            case "GetZPosition" -> {
+            case "GetZCoordinate" -> {
                 if (actualParams.size() != 0) {
                     throw new RuntimeException(getFuncCallErrorMessage(id, new int[]{0}, "", actualParams));
                 }
@@ -583,6 +584,7 @@ public MSType visitFuncCall(MineScriptParser.FuncCallContext ctx) {
                     } else {
                         TurtleCommands.print(server, expressionId + " is: " + text, messageType);
                     }
+                    timeout(1);
                 });
             }
             default -> {
@@ -763,7 +765,7 @@ private void timeout(int millis) {
         try {
             Thread.sleep(millis);
         } catch (InterruptedException e) {
-            throw new RuntimeException(e);
+            throw new ThreadInterruptedException("Thread was interrupted while waiting");
         }
     }
 }

src/main/interpreter/exceptions/ThreadInterruptedException.java

@@ -0,0 +1,5 @@
+package interpreter.exceptions;
+
+public class ThreadInterruptedException extends RuntimeException {
+    public ThreadInterruptedException(String message) { super(message); }
+}

src/main/java/minescript/block/custom/TurtleBlock.java

@@ -69,10 +69,9 @@ public void onStateReplaced(BlockState state, World world, BlockPos pos, BlockSt
             BlockEntity blockEntity = world.getBlockEntity(pos);
 
             if (blockEntity instanceof TurtleBlockEntity entity) {
-                PacketByteBuf buf = PacketByteBufs.create();
-                buf.writeBlockPos(entity.getPos());
-
-                ClientPlayNetworking.send(MineScriptPackets.STOP_INTERPRETER_ID, buf);
+                if (entity.interpreterThread != null && entity.interpreterThread.isAlive()) {
+                    entity.interpreterThread.interrupt();
+                }
             }
         }
         super.onStateReplaced(state, world, pos, newState, moved);

src/main/java/minescript/block/entity/TurtleBlockEntity.java

@@ -33,19 +33,37 @@ public void setTurtleInput(String input) {
 
     @Override
     public void writeNbt(NbtCompound nbt) {
-        nbt.putString("input", this.input.getString());
+        String text = input.getString();
+        int length = text.length();
+
+        int splits = (int) Math.ceil((double) length / 50000);
+        for (int i = 0; i < splits; i++) {
+            if (i == splits - 1)
+                nbt.putString("input" + i, text.substring(i * 50000));
+            else
+                nbt.putString("input" + i, text.substring(i * 50000, (i + 1) * 50000));
+        }
+
         super.writeNbt(nbt);
     }
 
     @Override
     public void readNbt(NbtCompound nbt) {
+        StringBuilder text = new StringBuilder();
+        int split = 0;
+        while (nbt.contains("input" + split)) {
+            text.append(nbt.getString("input" + split));
+            split++;
+        }
+        this.input = Text.of(text.toString());
         super.readNbt(nbt);
-        this.input = Text.of(nbt.getString("input"));
     }
 
     @Override
     public void writeScreenOpeningData(ServerPlayerEntity player, PacketByteBuf buf) {
-        buf.writeString(this.input.getString());
+        String text = this.input.getString();
+        buf.writeInt(text.length());
+        buf.writeString(text, text.length());
     }
 
     @Override

src/main/java/minescript/network/MineScriptPackets.java

@@ -7,10 +7,8 @@
 public class MineScriptPackets {
 
     public static final Identifier START_INTERPRETER_ID = new Identifier("minescript", "start_interpreter");
-    public static final Identifier STOP_INTERPRETER_ID = new Identifier("minescript", "stop_interpreter");
 
     public static void registerC2SPackets() {
         ServerPlayNetworking.registerGlobalReceiver(START_INTERPRETER_ID, StartInterpreterC2SPacket::receive);
-        ServerPlayNetworking.registerGlobalReceiver(STOP_INTERPRETER_ID, StopInterpreterC2SPacket::receive);
     }
 }

src/main/java/minescript/screen/TextEditorScreenHandler.java

@@ -23,7 +23,7 @@ public class TextEditorScreenHandler extends ScreenHandler {
 
     public TextEditorScreenHandler(int syncId, PlayerInventory inventory, PacketByteBuf buf) {
         this(syncId, inventory, (TurtleBlockEntity) null);
-        inputText = buf.readString();
+        inputText = buf.readString(buf.readInt());
     }
 
     public TextEditorScreenHandler(int syncId, PlayerInventory inventory, @Nullable TurtleBlockEntity entity) {