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 * (a) the Software, and
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 * (b) any piece of software and/or hardware listed in the lrgrwrks.txt file if
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package com.oracle.truffle.js.nodes.control;

import com.oracle.truffle.api.frame.VirtualFrame;
import com.oracle.truffle.api.instrumentation.Tag;
import com.oracle.truffle.api.nodes.Node;
import com.oracle.truffle.api.nodes.RepeatingNode;
import com.oracle.truffle.js.nodes.JavaScriptNode;
import com.oracle.truffle.js.nodes.access.WriteNode;
import com.oracle.truffle.js.runtime.Errors;
import com.oracle.truffle.js.runtime.objects.Undefined;

import java.util.Set;

public final class GeneratorWrapperNode extends JavaScriptNode implements RepeatingNode {
    @Child private JavaScriptNode childNode;
    @Child private JavaScriptNode stateNode;
    @Child private WriteNode writeStateNode;

    private GeneratorWrapperNode(JavaScriptNode childNode, JavaScriptNode stateNode, WriteNode writeStateNode) {
        assert childNode instanceof ResumableNode : childNode;
        this.childNode = childNode;
        this.stateNode = stateNode;
        this.writeStateNode = writeStateNode;
    }

    public static JavaScriptNode createWrapper(JavaScriptNode child, JavaScriptNode readStateNode, WriteNode writeStateNode) {
        JavaScriptNode wrapper = new GeneratorWrapperNode(child, readStateNode, writeStateNode);
        Node realChild = child instanceof WrapperNode ? ((WrapperNode) child).getDelegateNode() : child;
        wrapper.setSourceSection(realChild.getSourceSection());
        return wrapper;
    }

    @Override
    public boolean hasTag(Class<? extends Tag> tag) {
        Node child = childNode instanceof WrapperNode ? ((WrapperNode) childNode).getDelegateNode() : childNode;
        if (child instanceof JavaScriptNode) {
            return ((JavaScriptNode) child).hasTag(tag);
        }
        return super.hasTag(tag);
    }

    @Override
    public Object getNodeObject() {
        Node child = childNode instanceof WrapperNode ? ((WrapperNode) childNode).getDelegateNode() : childNode;
        if (child instanceof JavaScriptNode) {
            return ((JavaScriptNode) child).getNodeObject();
        } else {
            return null;
        }
    }

    @Override
    public Object execute(VirtualFrame frame) {
        Node child = childNode;
        if (child instanceof WrapperNode) {
            child = ((WrapperNode) child).getDelegateNode();
        }
        if (child instanceof ResumableNode) {
            return ((ResumableNode) child).resume(frame);
        } else {
            assert false : child.getClass();
            throw Errors.shouldNotReachHere();
        }
    }

    @Override
    public boolean executeRepeating(VirtualFrame frame) {
        assert childNode instanceof ResumableNode && childNode instanceof RepeatingNode : childNode.getClass();
        return (boolean) execute(frame);
    }

    public Object isResuming(VirtualFrame frame) {
        return stateNode.execute(frame) != Undefined.instance;
    }

    public Object getState(VirtualFrame frame) {
        return stateNode.execute(frame);
    }

    public int getStateAsInt(VirtualFrame frame) {
        Object value = stateNode.execute(frame);
        return (value instanceof Integer) ? (int) value : 0;
    }

    public void setState(VirtualFrame frame, Object resumeState) {
        writeStateNode.executeWrite(frame, resumeState);
    }

    public JavaScriptNode getResumableNode() {
        return childNode;
    }

    @Override
    protected JavaScriptNode copyUninitialized(Set<Class<? extends Tag>> materializedTags) {
        return createWrapper(cloneUninitialized(childNode, materializedTags), cloneUninitialized(stateNode, materializedTags),
                        (WriteNode) cloneUninitialized((JavaScriptNode) writeStateNode, materializedTags));
    }
}