SquirrelJME/SquirrelJME

// -*- Mode: Java; indent-tabs-mode: t; tab-width: 4 -*-
// ---------------------------------------------------------------------------
// SquirrelJME
//     Copyright (C) Stephanie Gawroriski <xer@multiphasicapps.net>
// ---------------------------------------------------------------------------
// SquirrelJME is under the Mozilla Public License Version 2.0.
// See license.mkd for licensing and copyright information.
// ---------------------------------------------------------------------------

package cc.squirreljme.jdwp.host;

import cc.squirreljme.jdwp.JDWPCommand;
import cc.squirreljme.jdwp.JDWPCommandSetObjectReference;
import cc.squirreljme.jdwp.JDWPErrorType;
import cc.squirreljme.jdwp.JDWPException;
import cc.squirreljme.jdwp.JDWPPacket;
import cc.squirreljme.jdwp.JDWPValueTag;
import cc.squirreljme.jdwp.host.views.JDWPViewObject;
import cc.squirreljme.jdwp.host.views.JDWPViewType;

/**
 * Object reference command set.
 *
 * @since 2021/03/14
 */
public enum JDWPHostCommandSetObjectReference
    implements JDWPCommandHandler
{
    /** The type that an object is. */
    REFERENCE_TYPE(JDWPCommandSetObjectReference.REFERENCE_TYPE)
    {
        /**
         * {@inheritDoc}
         * @since 2021/03/14
         */
        @Override
        public JDWPPacket execute(JDWPHostController __controller,
            JDWPPacket __packet)
            throws JDWPException
        {
            // Obtain the object and the type of that object
            Object object = __controller.readObject(__packet, false);
            Object type = (__controller.viewType().isValid(object) ?
                object : __controller.viewObject().type(object));
            
            // Register it for future reference
            __controller.getState().items.put(object);
            if (type != null)
                __controller.getState().items.put(type);
            
            JDWPPacket rv = __controller.reply(
                __packet.id(), JDWPErrorType.NO_ERROR);
                
            // Write the details of this class
            __controller.writeTaggedId(rv, type);
            
            return rv;
        }
    },
    
    /** Get field values. */
    GET_VALUES(JDWPCommandSetObjectReference.GET_VALUES)
    {
        /**
         * {@inheritDoc}
         * @since 2021/03/17
         */
        @Override
        public JDWPPacket execute(JDWPHostController __controller,
            JDWPPacket __packet)
            throws JDWPException
        {
            JDWPViewObject viewObject = __controller.viewObject();
            JDWPViewType viewType = __controller.viewType();
            
            // The type is needed to ensure the field class is valid
            Object object = __controller.readObject(__packet, false);
            Object type = viewObject.type(object);
            
            // Read in all field indexes and check for their validity
            int numFields = __packet.readInt();
            int[] fields = new int[numFields];
            for (int i = 0; i < numFields; i++)
            {
                int fieldDx = __packet.readId();
                if (!viewType.isValidField(type, fieldDx))
                    throw JDWPErrorType.INVALID_FIELD_ID.toss(type, fieldDx);
                
                fields[i] = fieldDx;
            }
            
            JDWPPacket rv = __controller.reply(
                __packet.id(), JDWPErrorType.NO_ERROR);
            
            // Write field mappings
            rv.writeInt(numFields);
            for (int i = 0; i < numFields; i++)
                try (JDWPHostValue value = __controller.value())
                {
                    // Determine the field type and its tag
                    String fieldSig = viewType.fieldSignature(type, fields[i]);
                    JDWPValueTag tag = JDWPValueTag.fromSignature(fieldSig);
                    
                    // Read the field value, fallback if not valid
                    if (!viewObject.readValue(object, fields[i], value))
                        value.set(tag.defaultValue);
                    
                    // Always write as tagged value
                    __controller.writeValue(rv, value, tag, false);
                    
                    // Store object for later use
                    if (value.get() != null && tag.isObject)
                        __controller.getState().items.put(value.get());
                }
            
            return rv;
        }
    },
    
    /** Is this object garbage collected? */
    IS_COLLECTED(JDWPCommandSetObjectReference.IS_COLLECTED)
    {
        /**
         * {@inheritDoc}
         * @since 2021/03/14
         */
        @Override
        public JDWPPacket execute(JDWPHostController __controller,
            JDWPPacket __packet)
            throws JDWPException
        {
            // Read the value but do nothing for it
            __controller.readObject(__packet, false);
            
            // If we still know about this object it was not GCed
            JDWPPacket rv = __controller.reply(
                __packet.id(), JDWPErrorType.NO_ERROR);
            rv.writeBoolean(false);
            
            return rv;
        }
    },
    
    /* End. */
    ;
    
    /** The base command. */
    public final JDWPCommand command;
    
    /** The ID of the packet. */
    public final int id;
    
    /**
     * Returns the ID used.
     * 
     * @param __id The ID used.
     * @since 2021/03/14
     */
    JDWPHostCommandSetObjectReference(JDWPCommand __id)
    {
        this.command = __id;
        this.id = __id.debuggerId();
    }
    
    /**
     * {@inheritDoc}
     * @since 2024/01/23
     */
    @Override
    public final JDWPCommand command()
    {
        return this.command;
    }
    
    /**
     * {@inheritDoc}
     * @since 2021/03/14
     */
    @Override
    public final int debuggerId()
    {
        return this.id;
    }
}