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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.runtime.builtins;

import com.oracle.truffle.api.CallTarget;
import com.oracle.truffle.api.CompilerDirectives.TruffleBoundary;
import com.oracle.truffle.api.RootCallTarget;
import com.oracle.truffle.api.dsl.Cached;
import com.oracle.truffle.api.dsl.Cached.Shared;
import com.oracle.truffle.api.dsl.CachedLanguage;
import com.oracle.truffle.api.frame.MaterializedFrame;
import com.oracle.truffle.api.interop.InteropLibrary;
import com.oracle.truffle.api.interop.UnsupportedMessageException;
import com.oracle.truffle.api.library.ExportLibrary;
import com.oracle.truffle.api.library.ExportMessage;
import com.oracle.truffle.api.object.DynamicObject;
import com.oracle.truffle.api.object.Shape;
import com.oracle.truffle.api.source.SourceSection;
import com.oracle.truffle.js.lang.JavaScriptLanguage;
import com.oracle.truffle.js.nodes.JSGuards;
import com.oracle.truffle.js.nodes.interop.ExportValueNode;
import com.oracle.truffle.js.nodes.interop.JSInteropExecuteNode;
import com.oracle.truffle.js.nodes.interop.JSInteropInstantiateNode;
import com.oracle.truffle.js.nodes.unary.IsCallableNode;
import com.oracle.truffle.js.runtime.JSException;
import com.oracle.truffle.js.runtime.JSFrameUtil;
import com.oracle.truffle.js.runtime.JSRealm;
import com.oracle.truffle.js.runtime.JSRuntime;
import com.oracle.truffle.js.runtime.interop.InteropFunction;
import com.oracle.truffle.js.runtime.objects.JSNonProxyObject;
import com.oracle.truffle.js.runtime.objects.JSObject;
import com.oracle.truffle.js.runtime.objects.Null;
import com.oracle.truffle.js.runtime.objects.Undefined;

@ExportLibrary(InteropLibrary.class)
public abstract class JSFunctionObject extends JSNonProxyObject {

    protected JSFunctionObject(Shape shape, JSFunctionData functionData, MaterializedFrame enclosingFrame, JSRealm realm, Object classPrototype) {
        super(shape);
        this.functionData = functionData;
        this.enclosingFrame = enclosingFrame;
        this.realm = realm;
        this.classPrototype = classPrototype;
    }

    
Shared function data. /** Shared function data. */
    private final JSFunctionData functionData;
    
Materialized frame of the enclosing function. /** Materialized frame of the enclosing function. */
    private final MaterializedFrame enclosingFrame;
    private final JSRealm realm;
    
The prototype property of the function object. Lazily initialized. /** The {@code prototype} property of the function object. Lazily initialized. */
    private Object classPrototype;

    public final JSFunctionData getFunctionData() {
        return functionData;
    }

    public final MaterializedFrame getEnclosingFrame() {
        return enclosingFrame;
    }

    public final JSRealm getRealm() {
        return realm;
    }

    public final Object getClassPrototype() {
        return classPrototype;
    }

    public void setClassPrototype(Object classPrototype) {
        this.classPrototype = classPrototype;
    }

    public Object getLexicalThis() {
        return classPrototype;
    }

    @Override
    public String getClassName() {
        return JSFunction.INSTANCE.getClassName(this);
    }

    @Override
    public String getBuiltinToStringTag() {
        return JSFunction.INSTANCE.getBuiltinToStringTag(this);
    }

    @ExportMessage
    public final boolean isExecutable(
                    @Cached IsCallableNode isCallable) {
        return isCallable.executeBoolean(this);
    }

    @ExportMessage
    public final Object execute(Object[] args,
                    @CachedLanguage JavaScriptLanguage language,
                    @Cached JSInteropExecuteNode callNode,
                    @Shared("exportValue") @Cached ExportValueNode exportNode) throws UnsupportedMessageException {
        language.interopBoundaryEnter(realm);
        try {
            Object result = callNode.execute(this, Undefined.instance, args);
            return exportNode.execute(result);
        } finally {
            language.interopBoundaryExit(realm);
        }
    }

    @ExportMessage
    public final boolean isInstantiable() {
        return JSRuntime.isConstructor(this);
    }

    @ExportMessage
    public final Object instantiate(Object[] args,
                    @CachedLanguage JavaScriptLanguage language,
                    @Cached JSInteropInstantiateNode callNode,
                    @Shared("exportValue") @Cached ExportValueNode exportNode) throws UnsupportedMessageException {
        language.interopBoundaryEnter(realm);
        try {
            Object result = callNode.execute(this, args);
            return exportNode.execute(result);
        } finally {
            language.interopBoundaryExit(realm);
        }
    }

    @ExportMessage
    public final boolean hasSourceLocation() {
        return getSourceLocationImpl(this) != null;
    }

    @ExportMessage
    public final SourceSection getSourceLocation() throws UnsupportedMessageException {
        SourceSection sourceSection = getSourceLocationImpl(this);
        if (sourceSection == null) {
            throw UnsupportedMessageException.create();
        }
        return sourceSection;
    }

    @TruffleBoundary
    private static SourceSection getSourceLocationImpl(DynamicObject receiver) {
        if (JSFunction.isJSFunction(receiver)) {
            DynamicObject func = receiver;
            CallTarget ct = JSFunction.getCallTarget(func);
            if (JSFunction.isBoundFunction(func)) {
                func = JSFunction.getBoundTargetFunction(func);
                ct = JSFunction.getCallTarget(func);
            }

            if (ct instanceof RootCallTarget) {
                return ((RootCallTarget) ct).getRootNode().getSourceSection();
            }
        }
        return null;
    }

    @SuppressWarnings("static-method")
    @ExportMessage
    public final boolean isMetaObject() {
        return true;
    }

    @SuppressWarnings("static-method")
    @TruffleBoundary
    @ExportMessage(name = "getMetaQualifiedName")
    @ExportMessage(name = "getMetaSimpleName")
    public final Object getMetaObjectName() {
        Object name = JSRuntime.getDataProperty(this, JSFunction.NAME);
        if (JSRuntime.isString(name)) {
            return JSRuntime.javaToString(name);
        }
        return "";
    }

    @SuppressWarnings("static-method")
    @TruffleBoundary
    @ExportMessage
    public final boolean isMetaInstance(Object instance) {
        Object constructorPrototype = JSRuntime.getDataProperty(this, JSObject.PROTOTYPE);
        if (JSGuards.isJSObject(constructorPrototype)) {
            Object obj = instance;
            if (obj instanceof InteropFunction) {
                obj = ((InteropFunction) obj).getFunction();
            }
            if (obj instanceof JSException) {
                obj = ((JSException) obj).getErrorObjectEager();
            }
            if (JSGuards.isJSObject(obj) && !JSProxy.isJSProxy(obj)) {
                DynamicObject proto = JSObject.getPrototype((DynamicObject) obj);
                while (proto != Null.instance) {
                    if (proto == constructorPrototype) {
                        return true;
                    }
                    if (JSProxy.isJSProxy(proto)) {
                        break;
                    }
                    proto = JSObject.getPrototype(proto);
                }
            }
        }
        return false;
    }

    public static JSFunctionObject create(Shape shape, JSFunctionData functionData, MaterializedFrame enclosingFrame, JSRealm realm, Object classPrototype) {
        return new Unbound(shape, functionData, enclosingFrame, realm, classPrototype);
    }

    public static JSFunctionObject createBound(Shape shape, JSFunctionData functionData, JSRealm realm, Object classPrototype,
                    DynamicObject boundTargetFunction, Object boundThis, Object[] boundArguments) {
        return new Bound(shape, functionData, realm, classPrototype, boundTargetFunction, boundThis, boundArguments);
    }

    public static final class Unbound extends JSFunctionObject {
        protected Unbound(Shape shape, JSFunctionData functionData, MaterializedFrame enclosingFrame, JSRealm realm, Object classPrototype) {
            super(shape, functionData, enclosingFrame, realm, classPrototype);
        }
    }

    public static final class Bound extends JSFunctionObject {
        protected Bound(Shape shape, JSFunctionData functionData, JSRealm realm, Object classPrototype,
                        DynamicObject boundTargetFunction, Object boundThis, Object[] boundArguments) {
            super(shape, functionData, JSFrameUtil.NULL_MATERIALIZED_FRAME, realm, classPrototype);
            this.boundTargetFunction = boundTargetFunction;
            this.boundThis = boundThis;
            this.boundArguments = boundArguments;
        }

        private DynamicObject boundTargetFunction;
        private Object boundThis;
        private Object[] boundArguments;

        public DynamicObject getBoundTargetFunction() {
            return boundTargetFunction;
        }

        public Object getBoundThis() {
            return boundThis;
        }

        public Object[] getBoundArguments() {
            return boundArguments;
        }
    }
}