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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.objects;

import com.oracle.truffle.api.CompilerDirectives.TruffleBoundary;
import com.oracle.truffle.api.frame.FrameDescriptor;
import com.oracle.truffle.api.frame.MaterializedFrame;
import com.oracle.truffle.api.object.DynamicObject;
import com.oracle.truffle.api.source.Source;
import com.oracle.truffle.js.runtime.JSContext;
import com.oracle.truffle.js.runtime.builtins.JSFunctionData;
import com.oracle.truffle.js.runtime.builtins.JSOrdinary;

import java.util.ArrayList;
import java.util.List;

Source Text Module Record.
/**
 * Source Text Module Record.
 */
public final class JSModuleRecord extends ScriptOrModule {

    public enum Status {
        Unlinked,
        Linking,
        Linked,
        Evaluating,
        Evaluated,
    }

    
Module parse node. /** Module parse node. */
    private final Object module;
    private final JSModuleLoader moduleLoader;

    
Module's instantiation/evaluation status. /** Module's instantiation/evaluation status. */
    private Status status;

    
Exception that occurred during evaluation. /** Exception that occurred during evaluation. */
    private Throwable evaluationError;
    
Implementation-specific: The result of ModuleExecution if no exception occurred. /** Implementation-specific: The result of ModuleExecution if no exception occurred. */
    private Object executionResult;

    private JSFunctionData functionData;
    private FrameDescriptor frameDescriptor;

    
Lazily initialized Module Namespace object ([[Namespace]]). /** Lazily initialized Module Namespace object ({@code [[Namespace]]}). */
    private DynamicObject namespace;
    
Lazily initialized frame ([[Environment]]). /** Lazily initialized frame ({@code [[Environment]]}). */
    private MaterializedFrame environment;
    
Lazily initialized import.meta object ([[ImportMeta]]). /** Lazily initialized import.meta object ({@code [[ImportMeta]]}). */
    private DynamicObject importMeta;

    
Auxiliary field used during Instantiate and Evaluate only. If [[Status]] is "instantiating"
or "evaluating", this nonnegative number records the point at which the module was first
visited during the ongoing depth-first traversal of the dependency graph.
/**
     * Auxiliary field used during Instantiate and Evaluate only. If [[Status]] is "instantiating"
     * or "evaluating", this nonnegative number records the point at which the module was first
     * visited during the ongoing depth-first traversal of the dependency graph.
     */
    private int dfsIndex;
    
Auxiliary field used during Instantiate and Evaluate only. If [[Status]] is "instantiating"
or "evaluating", this is either the module's own [[DFSIndex]] or that of an "earlier" module
in the same strongly connected component.
/**
     * Auxiliary field used during Instantiate and Evaluate only. If [[Status]] is "instantiating"
     * or "evaluating", this is either the module's own [[DFSIndex]] or that of an "earlier" module
     * in the same strongly connected component.
     */
    private int dfsAncestorIndex;

    /*
     * Used to store the top-level promise created as a result of top-level await modules
     * evaluation.
     */
    private Object topLevelAwaitModuleLoadingContinuation;

    public JSModuleRecord(Object module, JSContext context, JSModuleLoader moduleLoader, Source source) {
        super(context, source);
        this.module = module;
        this.moduleLoader = moduleLoader;
        setUninstantiated();
    }

    public Object getModule() {
        return module;
    }

    public JSModuleLoader getModuleLoader() {
        return moduleLoader;
    }

    public JSFunctionData getFunctionData() {
        assert functionData != null;
        return functionData;
    }

    public void setFunctionData(JSFunctionData functionData) {
        assert this.functionData == null;
        this.functionData = functionData;
    }

    public FrameDescriptor getFrameDescriptor() {
        assert frameDescriptor != null;
        return frameDescriptor;
    }

    public void setFrameDescriptor(FrameDescriptor frameDescriptor) {
        assert this.frameDescriptor == null;
        this.frameDescriptor = frameDescriptor;
    }

    public Status getStatus() {
        return status;
    }

    public void setStatus(Status status) {
        this.status = status;
    }

    public boolean isEvaluated() {
        return getStatus() == Status.Evaluated;
    }

    public Throwable getEvaluationError() {
        assert isEvaluated();
        return evaluationError;
    }

    public void setEvaluationError(Throwable evaluationError) {
        assert isEvaluated();
        this.evaluationError = evaluationError;
    }

    public DynamicObject getNamespace() {
        return namespace;
    }

    public void setNamespace(DynamicObject namespace) {
        assert this.namespace == null;
        this.namespace = namespace;
    }

    public MaterializedFrame getEnvironment() {
        return environment;
    }

    public void setEnvironment(MaterializedFrame environment) {
        assert this.environment == null;
        assert this.frameDescriptor == environment.getFrameDescriptor();
        this.environment = environment;
    }

    public int getDFSIndex() {
        assert dfsIndex >= 0;
        return dfsIndex;
    }

    public void setDFSIndex(int dfsIndex) {
        this.dfsIndex = dfsIndex;
    }

    public int getDFSAncestorIndex() {
        assert dfsAncestorIndex >= 0;
        return dfsAncestorIndex;
    }

    public void setDFSAncestorIndex(int dfsAncestorIndex) {
        this.dfsAncestorIndex = dfsAncestorIndex;
    }

    public Object getExecutionResult() {
        return executionResult;
    }

    public void setExecutionResult(Object executionResult) {
        this.executionResult = executionResult;
    }

    public DynamicObject getImportMeta() {
        if (importMeta == null) {
            importMeta = createMetaObject();
        }
        return importMeta;
    }

    private DynamicObject createMetaObject() {
        DynamicObject metaObj = JSOrdinary.createWithNullPrototype(context);
        if (context.hasImportMetaInitializerBeenSet()) {
            context.notifyImportMetaInitializer(metaObj, this);
        } else {
            initializeMetaObject(metaObj);
        }
        return metaObj;
    }

    @TruffleBoundary
    private void initializeMetaObject(DynamicObject metaObj) {
        JSObject.set(metaObj, "url", getSource().getURI().toString());
    }

    public void setUninstantiated() {
        setStatus(Status.Unlinked);
        this.environment = null;
        this.dfsIndex = -1;
        this.dfsAncestorIndex = -1;
    }

    // ##### Top-level await

    // [[Async]]
    private boolean async = false;
    // [[AsyncEvaluating]]
    private boolean asyncEvaluating = false;
    // [[TopLevelCapability]]
    private PromiseCapabilityRecord topLevelPromiseCapability = null;
    // [[AsyncParentModules]]
    private List<JSModuleRecord> asyncParentModules = null;
    // [[PendingAsyncDependencies]]
    private int pendingAsyncDependencies = 0;

    public PromiseCapabilityRecord getTopLevelCapability() {
        return topLevelPromiseCapability;
    }

    public void setTopLevelCapability(PromiseCapabilityRecord capability) {
        this.topLevelPromiseCapability = capability;
    }

    public boolean isAsyncEvaluating() {
        return asyncEvaluating;
    }

    public List<JSModuleRecord> getAsyncParentModules() {
        return asyncParentModules;
    }

    public void setPendingAsyncDependencies(int value) {
        pendingAsyncDependencies = value;
    }

    public void initAsyncParentModules() {
        assert asyncParentModules == null;
        asyncParentModules = new ArrayList<>();
    }

    public void incPendingAsyncDependencies() {
        pendingAsyncDependencies++;
    }

    public void decPendingAsyncDependencies() {
        pendingAsyncDependencies--;
    }

    public void appendAsyncParentModules(JSModuleRecord moduleRecord) {
        asyncParentModules.add(moduleRecord);
    }

    public int getPendingAsyncDependencies() {
        return pendingAsyncDependencies;
    }

    public void setAsyncEvaluating(boolean value) {
        asyncEvaluating = value;
    }

    public boolean isTopLevelAsync() {
        return async;
    }

    public void setTopLevelAsync() {
        async = true;
    }

    public void setExecutionContinuation(Object continuation) {
        this.topLevelAwaitModuleLoadingContinuation = continuation;
    }

    public Object getExecutionContinuation() {
        return topLevelAwaitModuleLoadingContinuation;
    }

}