SquirrelJME/SquirrelJME

// -*- Mode: Java; indent-tabs-mode: t; tab-width: 4 -*-
// ---------------------------------------------------------------------------
// Multi-Phasic Applications: 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.debugger;

import cc.squirreljme.jdwp.JDWPEventModifierKind;
import cc.squirreljme.jdwp.JDWPPacket;
import cc.squirreljme.jdwp.JDWPStepDepth;
import cc.squirreljme.jdwp.JDWPStepSize;

/**
 * Single step event modifier.
 *
 * @since 2024/01/26
 */
public class EventModifierSingleStep
    implements EventModifier
{
    /** The step depth. */
    protected final JDWPStepDepth depth;
    
    /** The step size. */
    protected final JDWPStepSize size;
    
    /** The thread to step in. */
    protected final InfoThread thread;
    
    /**
     * Initializes the single step.
     *
     * @param __thread The thread to step in.
     * @param __depth The step depth.
     * @param __size The step size.
     * @throws NullPointerException On null arguments.
     * @since 2024/01/26
     */
    public EventModifierSingleStep(InfoThread __thread, JDWPStepDepth __depth,
        JDWPStepSize __size)
        throws NullPointerException
    {
        if (__thread == null || __depth == null || __size == null)
            throw new NullPointerException("NARG");
        
        this.thread = __thread;
        this.depth = __depth;
        this.size = __size;
    }
    
    /**
     * {@inheritDoc}
     * @since 2024/01/26
     */
    @Override
    public void write(DebuggerState __debuggerState, JDWPPacket __packet)
    {
        // Single step in this thread
        __packet.writeByte(JDWPEventModifierKind.CALL_STACK_STEPPING
            .debuggerId());
        __packet.writeId(this.thread.id);
        __packet.writeInt(this.size.debuggerId());
        __packet.writeInt(this.depth.debuggerId());
    }
}