/*
 * Copyright (c) 1996, 2021, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 */
package sun.awt.windows;

import java.util.Map;
import java.util.WeakHashMap;

abstract class WObjectPeer {

    static {
        initIDs();
    }

    // The Windows handle for the native widget.
    volatile long pData;
    // if the native peer has been destroyed
    private volatile boolean destroyed;
    // The associated AWT object.
    volatile Object target;

    private volatile boolean disposed;

    // set from JNI if any errors in creating the peer occur
    volatile Error createError;

    // used to synchronize the state of this peer
    private final Object stateLock = new Object();

    private volatile Map<WObjectPeer, WObjectPeer> childPeers;

    public static WObjectPeer getPeerForTarget(Object t) {
        WObjectPeer peer = (WObjectPeer) WToolkit.targetToPeer(t);
        return peer;
    }

    public long getData() {
        return pData;
    }

    public Object getTarget() {
        return target;
    }

    public final Object getStateLock() {
        return stateLock;
    }

    /*
     * Subclasses should override disposeImpl() instead of dispose(). Client
     * code should always invoke dispose(), never disposeImpl().
     */
    protected abstract void disposeImpl();
    public final void dispose() {
        boolean call_disposeImpl = false;

        synchronized (this) {
            if (!disposed) {
                disposed = call_disposeImpl = true;
            }
        }

        if (call_disposeImpl) {
            if (childPeers != null) {
                disposeChildPeers();
            }
            disposeImpl();
        }
    }
    protected final boolean isDisposed() {
        return disposed;
    }

    /**
     * Initialize JNI field and method IDs
     */
    private static native void initIDs();

    // if a child peer existence depends on this peer, add it to this collection
    final void addChildPeer(WObjectPeer child) {
        synchronized (getStateLock()) {
            if (childPeers == null) {
                childPeers = new WeakHashMap<>();
            }
            if (isDisposed()) {
                throw new IllegalStateException("Parent peer is disposed");
            }
            childPeers.put(child, this);
        }
    }

    // called to dispose dependent child peers
    private void disposeChildPeers() {
        synchronized (getStateLock()) {
            for (WObjectPeer child : childPeers.keySet()) {
                if (child != null) {
                    try {
                        child.dispose();
                    }
                    catch (Exception e) {
                        // ignored
                    }
                }
            }
        }
    }
}
