package bluej.stride.framedjava.frames;

import bluej.stride.framedjava.ast.ExpressionSlotFragment;
import bluej.stride.generic.FrameContentItem;
import bluej.utility.javafx.JavaFXUtil;
import javafx.application.Platform;
import bluej.stride.framedjava.ast.FilledExpressionSlotFragment;
import bluej.stride.framedjava.elements.AssignElement;
import bluej.stride.framedjava.slots.ExpressionSlot;
import bluej.stride.framedjava.slots.FilledExpressionSlot;
import bluej.stride.generic.FrameFactory;
import bluej.stride.generic.InteractionManager;
import bluej.stride.generic.SingleLineFrame;
import bluej.stride.slots.Focus;
import bluej.stride.slots.HeaderItem;
import bluej.stride.slots.SlotLabel;
import bluej.utility.javafx.SharedTransition;
import threadchecker.OnThread;
import threadchecker.Tag;




| A set statement for assignment, e.g. "set x = 1"
|* @author Fraser McKay
 
*/
public class AssignFrame extends SingleLineFrame
 
implements CodeFrame<AssignElement>, DebuggableFrame{     
   public static final String ASSIGN_SYMBOL = "\u21D0";
   
   private final ExpressionSlot<FilledExpressionSlotFragment> slotLHS;
   
   private final ExpressionSlot<FilledExpressionSlotFragment> slotRHS;
   
   private AssignElement element;
   
   private SlotLabel assignLabel;
|
|/**
| Default constructor.
| @param editor
|
private AssignFrame(InteractionManager editor)
   {
      super(editor, null, "set-");
       
      
      slotRHS = new FilledExpressionSlot(editor, this, this, getHeaderRow(), "", FilledExpressionSlot.SRC_HINTS);
      slotRHS.setSimplePromptText("new-value");
       
      slotLHS = new FilledExpressionSlot(editor, this, this, getHeaderRow(), "assign-lhs-");
      slotLHS.setSimplePromptText("variable");
       
      assignLabel = new SlotLabel(ASSIGN_SYMBOL);
      setHeaderRow(slotLHS, assignLabel, slotRHS, previewSemi);
        
      slotLHS.addClosingChar('=');
      slotLHS.addClosingChar(' ');     
      }
    
   
   
   AssignFrame(InteractionManager editor, String lhs, String rhs)
   {
      this(editor);
      slotLHS.setText(lhs);
      slotRHS.setText(rhs);
      if (Platform.isFxApplicationThread())
       {
         JavaFXUtil.runPlatformLater(() -> slotRHS.requestFocus(Focus.LEFT));         
         }     
      }
    
   
   public AssignFrame(InteractionManager editor, FilledExpressionSlotFragment lhs, FilledExpressionSlotFragment rhs, boolean enabled)
   {
      this(editor);
      slotLHS.setText(lhs);
      slotRHS.setText(rhs);
      frameEnabledProperty.set(enabled);     
      }

   
   @Override
   
   public void regenerateCode()
   {        
      element = new AssignElement(this, slotLHS.getSlotElement(), slotRHS.getSlotElement(), 
      frameEnabledProperty.get());     
      }
    
   
   @Override
   
   public AssignElement getCode()
   {        
      return element;     
      }
    
   
   public static FrameFactory getFactory()
   {        
      return new FrameFactory<AssignFrame>() {            
         @Override
           
         public AssignFrame createBlock(InteractionManager editor)
           {                
            return new AssignFrame(editor);             
            }
                        
           
         @Override 
           
         public Class getBlockClass()
           {                 
            return AssignFrame.class;             
            }         
         };
      }
    
   
   public ExpressionSlot getLHS()
   {        
      return slotLHS;     
      }
    
   
   public ExpressionSlot getRHS()
   {        
      return slotRHS;     
      }

   
   @Override
   @OnThread(Tag.FXPlatform)
   
   public boolean backspaceAtStart(FrameContentItem row, HeaderItem src)
   {
      if (src == slotRHS)
       {
         collapseIntoMethodCall();
           
         return true;         
         }
       

      else{ return super.backspaceAtStart(row, src);
         }     
      }

   
   @Override
   @OnThread(Tag.FXPlatform)
   
   public boolean deleteAtEnd(FrameContentItem row, HeaderItem src)
   {
      if (src == slotLHS)
       {
         collapseIntoMethodCall();
           
         return true;         
         }
       
      return false;     
      }

   @OnThread(Tag.FXPlatform)
   
   private void collapseIntoMethodCall()
   {        
      getParentCanvas().replaceBlock(this, new CallFrame(getEditor(), slotLHS.getText(), slotRHS.getText()));             
      }

   
   @Override
   
   public @OnThread(Tag.FXPlatform) void setView(View oldView, View newView, SharedTransition animation)
   {
      super.setView(oldView, newView, animation);
      assignLabel.setText(newView == View.JAVA_PREVIEW ? "=" : ASSIGN_SYMBOL);     
      } 
   }