feat(objectionary#376): each agent decides when to move to the next p…

…osition

src/main/java/org/eolang/opeo/decompilation/DecompilerState.java

@@ -26,10 +26,13 @@
 import java.util.Deque;
 import java.util.Iterator;
 import java.util.LinkedList;
+import java.util.Optional;
+import javax.swing.text.html.Option;
 import lombok.EqualsAndHashCode;
 import lombok.ToString;
 import org.eolang.opeo.ast.AstNode;
 import org.eolang.opeo.ast.Opcode;
+import org.objectweb.asm.Opcodes;
 import org.objectweb.asm.Type;
 
 /**
@@ -86,15 +89,17 @@ public boolean hasInstructions() {
     }
 
     public void move() {
-        this.opcodes.pop();
+        if (!this.opcodes.isEmpty()) {
+            this.opcodes.pop();
+        }
     }
 
     /**
      * Retrieve current bytecode instruction.
      * @return Current bytecode instruction.
      */
     public Opcode instruction() {
-        return this.opcodes.peek();
+        return Optional.ofNullable(this.opcodes.peek()).orElse(new Opcode(-100));
 //        final Iterator<AstNode> iterator = this.stack().iterator();
 //        while (iterator.hasNext()) {
 //            final AstNode next = iterator.next();

src/main/java/org/eolang/opeo/decompilation/agents/AddAgent.java

@@ -54,6 +54,7 @@ public void handle(final DecompilerState state) {
             final AstNode right = state.stack().pop();
             final AstNode left = state.stack().pop();
             state.stack().push(new Addition(left, right));
+            state.move();
         }
     }
 

src/main/java/org/eolang/opeo/decompilation/agents/AllAgents.java

@@ -59,54 +59,55 @@ public AllAgents(final boolean counting) {
         this(
             new MapOf<Integer, DecompilationAgent>(
                 new MapEntry<>(Opcodes.ICONST_M1, new ConstAgent()),
-//                new MapEntry<>(Opcodes.ICONST_0, new ConstAgent()),
-//                new MapEntry<>(Opcodes.ICONST_1, new ConstAgent()),
-//                new MapEntry<>(Opcodes.ICONST_2, new ConstAgent()),
-//                new MapEntry<>(Opcodes.ICONST_3, new ConstAgent()),
-//                new MapEntry<>(Opcodes.ICONST_4, new ConstAgent()),
-//                new MapEntry<>(Opcodes.ICONST_5, new ConstAgent()),
-//                new MapEntry<>(Opcodes.LCONST_0, new ConstAgent()),
-//                new MapEntry<>(Opcodes.LCONST_1, new ConstAgent()),
-//                new MapEntry<>(Opcodes.FCONST_0, new ConstAgent()),
-//                new MapEntry<>(Opcodes.FCONST_1, new ConstAgent()),
-//                new MapEntry<>(Opcodes.FCONST_2, new ConstAgent()),
-//                new MapEntry<>(Opcodes.DCONST_0, new ConstAgent()),
-//                new MapEntry<>(Opcodes.DCONST_1, new ConstAgent()),
+                new MapEntry<>(Opcodes.ICONST_0, new ConstAgent()),
+                new MapEntry<>(Opcodes.ICONST_1, new ConstAgent()),
+                new MapEntry<>(Opcodes.ICONST_2, new ConstAgent()),
+                new MapEntry<>(Opcodes.ICONST_3, new ConstAgent()),
+                new MapEntry<>(Opcodes.ICONST_4, new ConstAgent()),
+                new MapEntry<>(Opcodes.ICONST_5, new ConstAgent()),
+                new MapEntry<>(Opcodes.LCONST_0, new ConstAgent()),
+                new MapEntry<>(Opcodes.LCONST_1, new ConstAgent()),
+                new MapEntry<>(Opcodes.FCONST_0, new ConstAgent()),
+                new MapEntry<>(Opcodes.FCONST_1, new ConstAgent()),
+                new MapEntry<>(Opcodes.FCONST_2, new ConstAgent()),
+                new MapEntry<>(Opcodes.DCONST_0, new ConstAgent()),
+                new MapEntry<>(Opcodes.DCONST_1, new ConstAgent()),
+//
                 new MapEntry<>(Opcodes.IADD, new AddAgent()),
-//                new MapEntry<>(Opcodes.LADD, new AddAgent()),
-//                new MapEntry<>(Opcodes.FADD, new AddAgent()),
-//                new MapEntry<>(Opcodes.DADD, new AddAgent()),
+                new MapEntry<>(Opcodes.LADD, new AddAgent()),
+                new MapEntry<>(Opcodes.FADD, new AddAgent()),
+                new MapEntry<>(Opcodes.DADD, new AddAgent()),
                 new MapEntry<>(Opcodes.ISUB, new SubstractionAgent()),
-//                new MapEntry<>(Opcodes.LSUB, new SubstractionAgent()),
-//                new MapEntry<>(Opcodes.FSUB, new SubstractionAgent()),
-//                new MapEntry<>(Opcodes.DSUB, new SubstractionAgent()),
+                new MapEntry<>(Opcodes.LSUB, new SubstractionAgent()),
+                new MapEntry<>(Opcodes.FSUB, new SubstractionAgent()),
+                new MapEntry<>(Opcodes.DSUB, new SubstractionAgent()),
                 new MapEntry<>(Opcodes.IMUL, new MulAgent()),
                 new MapEntry<>(Opcodes.IF_ICMPGT, new IfAgent()),
                 new MapEntry<>(Opcodes.I2B, new CastAgent()),
-//                new MapEntry<>(Opcodes.I2C, new CastAgent()),
-//                new MapEntry<>(Opcodes.I2S, new CastAgent()),
-//                new MapEntry<>(Opcodes.I2L, new CastAgent()),
-//                new MapEntry<>(Opcodes.I2F, new CastAgent()),
-//                new MapEntry<>(Opcodes.I2D, new CastAgent()),
-//                new MapEntry<>(Opcodes.L2I, new CastAgent()),
-//                new MapEntry<>(Opcodes.L2F, new CastAgent()),
-//                new MapEntry<>(Opcodes.L2D, new CastAgent()),
-//                new MapEntry<>(Opcodes.F2I, new CastAgent()),
-//                new MapEntry<>(Opcodes.F2L, new CastAgent()),
-//                new MapEntry<>(Opcodes.F2D, new CastAgent()),
-//                new MapEntry<>(Opcodes.D2I, new CastAgent()),
-//                new MapEntry<>(Opcodes.D2L, new CastAgent()),
-//                new MapEntry<>(Opcodes.D2F, new CastAgent()),
+                new MapEntry<>(Opcodes.I2C, new CastAgent()),
+                new MapEntry<>(Opcodes.I2S, new CastAgent()),
+                new MapEntry<>(Opcodes.I2L, new CastAgent()),
+                new MapEntry<>(Opcodes.I2F, new CastAgent()),
+                new MapEntry<>(Opcodes.I2D, new CastAgent()),
+                new MapEntry<>(Opcodes.L2I, new CastAgent()),
+                new MapEntry<>(Opcodes.L2F, new CastAgent()),
+                new MapEntry<>(Opcodes.L2D, new CastAgent()),
+                new MapEntry<>(Opcodes.F2I, new CastAgent()),
+                new MapEntry<>(Opcodes.F2L, new CastAgent()),
+                new MapEntry<>(Opcodes.F2D, new CastAgent()),
+                new MapEntry<>(Opcodes.D2I, new CastAgent()),
+                new MapEntry<>(Opcodes.D2L, new CastAgent()),
+                new MapEntry<>(Opcodes.D2F, new CastAgent()),
                 new MapEntry<>(Opcodes.ILOAD, new LoadAgent()),
-//                new MapEntry<>(Opcodes.LLOAD, new LoadAgent()),
-//                new MapEntry<>(Opcodes.FLOAD, new LoadAgent()),
-//                new MapEntry<>(Opcodes.DLOAD, new LoadAgent()),
-//                new MapEntry<>(Opcodes.ALOAD, new LoadAgent()),
+                new MapEntry<>(Opcodes.LLOAD, new LoadAgent()),
+                new MapEntry<>(Opcodes.FLOAD, new LoadAgent()),
+                new MapEntry<>(Opcodes.DLOAD, new LoadAgent()),
+                new MapEntry<>(Opcodes.ALOAD, new LoadAgent()),
                 new MapEntry<>(Opcodes.ISTORE, new StoreAgent()),
-//                new MapEntry<>(Opcodes.LSTORE, new StoreAgent()),
-//                new MapEntry<>(Opcodes.FSTORE, new StoreAgent()),
-//                new MapEntry<>(Opcodes.DSTORE, new StoreAgent()),
-//                new MapEntry<>(Opcodes.ASTORE, new StoreAgent()),
+                new MapEntry<>(Opcodes.LSTORE, new StoreAgent()),
+                new MapEntry<>(Opcodes.FSTORE, new StoreAgent()),
+                new MapEntry<>(Opcodes.DSTORE, new StoreAgent()),
+                new MapEntry<>(Opcodes.ASTORE, new StoreAgent()),
                 new MapEntry<>(Opcodes.AASTORE, new StoreToArrayAgent()),
                 new MapEntry<>(Opcodes.ANEWARRAY, new NewArrayAgent()),
                 new MapEntry<>(Opcodes.CHECKCAST, new CheckCastAgent()),
@@ -124,8 +125,8 @@ public AllAgents(final boolean counting) {
                 new MapEntry<>(Opcodes.LDC, new LdcAgent()),
                 new MapEntry<>(Opcodes.POP, new PopAgent()),
                 new MapEntry<>(Opcodes.RETURN, new ReturnAgent()),
-//                new MapEntry<>(Opcodes.IRETURN, new ReturnAgent()),
-//                new MapEntry<>(Opcodes.ARETURN, new ReturnAgent()),
+                new MapEntry<>(Opcodes.IRETURN, new ReturnAgent()),
+                new MapEntry<>(Opcodes.ARETURN, new ReturnAgent()),
                 new MapEntry<>(LabelInstruction.LABEL_OPCODE, new LabelAgent())
 //                , new MapEntry<>(AllAgents.UNIMPLEMENTED, new UnimplementedAgent(counting))
             )
@@ -143,10 +144,9 @@ private AllAgents(final Map<Integer, DecompilationAgent> agents) {
     @Override
     public void handle(final DecompilerState state) {
         //todo: until?
-        int hash;
         while (state.hasInstructions()) {
             this.agents.values().forEach(agent -> agent.handle(state));
-            state.move();
+//            state.move();
         }
 //        do {
 //            hash = state.hashCode();

src/main/java/org/eolang/opeo/decompilation/agents/BipushAgent.java

@@ -47,6 +47,7 @@ public final class BipushAgent implements DecompilationAgent {
     public void handle(final DecompilerState state) {
         if (BipushAgent.SUPPORTED.contains(state.instruction().opcode())) {
             state.stack().push(new Literal(state.operand(0)));
+            state.move();
         }
     }
 

src/main/java/org/eolang/opeo/decompilation/agents/CastAgent.java

@@ -67,6 +67,7 @@ public void handle(final DecompilerState state) {
                     state.stack().pop()
                 )
             );
+            state.move();
         }
     }
 

src/main/java/org/eolang/opeo/decompilation/agents/CheckCastAgent.java

@@ -52,6 +52,7 @@ public void handle(final DecompilerState state) {
             final AstNode value = state.stack().pop();
             final Object type = state.operand(0);
             state.stack().push(new CheckCast(Type.getObjectType((String) type), value));
+            state.move();
         }
     }
 }

src/main/java/org/eolang/opeo/decompilation/agents/ConstAgent.java

@@ -92,6 +92,7 @@ public void handle(final DecompilerState state) {
                     state.stack().push(res);
                     break;
             }
+            state.move();
         }
 
     }

src/main/java/org/eolang/opeo/decompilation/agents/DupAgent.java

@@ -49,6 +49,7 @@ public void handle(final DecompilerState state) {
         if (DupAgent.SUPPORTED.contains(state.instruction().opcode())) {
             final OperandStack stack = state.stack();
             stack.push(new Duplicate(stack.pop()));
+            state.move();
         }
     }
 

src/main/java/org/eolang/opeo/decompilation/agents/GetFieldAgent.java

@@ -51,6 +51,7 @@ public void handle(final DecompilerState state) {
                         .type("field")
                 )
             );
+            state.move();
         }
     }
 

src/main/java/org/eolang/opeo/decompilation/agents/GetStaticAgent.java

@@ -40,6 +40,7 @@ public void handle(final DecompilerState state) {
             final String method = (String) state.operand(1);
             final String descriptor = (String) state.operand(2);
             state.stack().push(new ClassField(klass, method, descriptor));
+            state.move();
         }
     }
 }

src/main/java/org/eolang/opeo/decompilation/agents/IfAgent.java

@@ -57,6 +57,7 @@ public void handle(final DecompilerState state) {
             final AstNode first = stack.pop();
             final Label operand = (Label) state.operand(0);
             stack.push(new If(first, second, operand));
+            state.move();
         }
     }
 }

src/main/java/org/eolang/opeo/decompilation/agents/InvokedynamicAgent.java

@@ -54,6 +54,7 @@ public void handle(final DecompilerState state) {
                 args
             );
             state.stack().push(node);
+            state.move();
         }
     }
 

src/main/java/org/eolang/opeo/decompilation/agents/InvokeinterfaceAgent.java

@@ -73,6 +73,7 @@ public void handle(final DecompilerState state) {
                     args
                 )
             );
+            state.move();
         }
     }
 }

src/main/java/org/eolang/opeo/decompilation/agents/InvokespecialAgent.java

@@ -103,6 +103,7 @@ public void handle(final DecompilerState state) {
                     new Super(target, args, descriptor, type, name)
                 );
             }
+            state.move();
         }
     }
 

src/main/java/org/eolang/opeo/decompilation/agents/InvokestaticAgent.java

@@ -60,6 +60,7 @@ public void handle(final DecompilerState state) {
                     args
                 )
             );
+            state.move();
         }
     }
 }

src/main/java/org/eolang/opeo/decompilation/agents/InvokevirtualAgent.java

@@ -73,6 +73,7 @@ public void handle(final DecompilerState state) {
                     args
                 )
             );
+            state.move();
         }
     }
 }

src/main/java/org/eolang/opeo/decompilation/agents/LabelAgent.java

@@ -43,6 +43,7 @@ public void handle(final DecompilerState state) {
                 new Label(String.class.cast(state.operand(0)))
             );
             state.stack().push(node);
+            state.move();
         }
     }
 }

src/main/java/org/eolang/opeo/decompilation/agents/LdcAgent.java

@@ -39,6 +39,7 @@ public void handle(final DecompilerState state) {
         if (state.instruction().opcode() == Opcodes.LDC) {
             final Object operand = state.operand(0);
             state.stack().push(new Constant(operand));
+            state.move();
         }
     }
 

src/main/java/org/eolang/opeo/decompilation/agents/LoadAgent.java

@@ -59,6 +59,7 @@ public void handle(final DecompilerState state) {
             state.stack().push(
                 state.variable(index, LoadAgent.type(opcode))
             );
+            state.move();
         }
     }
 

src/main/java/org/eolang/opeo/decompilation/agents/MulAgent.java

@@ -54,7 +54,7 @@ public void handle(final DecompilerState state) {
             final AstNode right = state.stack().pop();
             final AstNode left = state.stack().pop();
             state.stack().push(new Multiplication(left, right));
-
+            state.move();
         }
     }
 

src/main/java/org/eolang/opeo/decompilation/agents/NewAgent.java

@@ -48,6 +48,7 @@ public final class NewAgent implements DecompilationAgent {
     public void handle(final DecompilerState state) {
         if (NewAgent.SUPPORTED.contains(state.instruction().opcode())) {
             state.stack().push(new NewAddress(state.operand(0).toString()));
+            state.move();
         }
     }
 

src/main/java/org/eolang/opeo/decompilation/agents/NewArrayAgent.java

@@ -54,6 +54,7 @@ public void handle(final DecompilerState state) {
             final OperandStack stack = state.stack();
             final AstNode size = stack.pop();
             stack.push(new Reference(new ArrayConstructor(size, type)));
+            state.move();
         }
     }
 }

src/main/java/org/eolang/opeo/decompilation/agents/PopAgent.java

@@ -40,6 +40,7 @@ public void handle(final DecompilerState state) {
         if (state.instruction().opcode() == Opcodes.POP) {
             final OperandStack stack = state.stack();
             stack.push(new Popped(stack.pop()));
+            state.move();
         }
     }
 

src/main/java/org/eolang/opeo/decompilation/agents/PutFieldAgent.java

@@ -57,6 +57,7 @@ public void handle(final DecompilerState state) {
                     value
                 )
             );
+            state.move();
         }
     }
 }

src/main/java/org/eolang/opeo/decompilation/agents/ReturnAgent.java

@@ -72,6 +72,7 @@ public void handle(final DecompilerState state) {
                     String.format("Unexpected opcode: %d", opcode)
                 );
             }
+            state.move();
         }
     }
 }

src/main/java/org/eolang/opeo/decompilation/agents/StoreAgent.java

@@ -65,6 +65,7 @@ public void handle(final DecompilerState state) {
                     value
                 )
             );
+            state.move();
         }
 
     }

src/main/java/org/eolang/opeo/decompilation/agents/StoreToArrayAgent.java

@@ -67,6 +67,7 @@ public void handle(final DecompilerState state) {
             } catch (final IllegalStateException exception) {
                 state.stack().push(new StoreArray(array, index, value));
             }
+            state.move();
         }
     }
 

src/main/java/org/eolang/opeo/decompilation/agents/SubstractionAgent.java

@@ -54,6 +54,7 @@ public void handle(final DecompilerState state) {
             final AstNode right = state.stack().pop();
             final AstNode left = state.stack().pop();
             state.stack().push(new Substraction(left, right));
+            state.move();
         }
     }
 }