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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.graal.python.lib;

import static com.oracle.graal.python.nodes.BuiltinNames.T_BUILTINS;
import static com.oracle.graal.python.nodes.BuiltinNames.T_GLOBALS;
import static com.oracle.graal.python.nodes.BuiltinNames.T_LOCALS;
import static com.oracle.graal.python.nodes.BuiltinNames.T___BUILTINS__;
import static com.oracle.graal.python.nodes.BuiltinNames.T___IMPORT__;
import static com.oracle.graal.python.util.PythonUtils.tsLiteral;

import com.oracle.graal.python.builtins.objects.dict.PDict;
import com.oracle.graal.python.builtins.objects.function.PKeyword;
import com.oracle.graal.python.nodes.PNodeWithState;
import com.oracle.graal.python.nodes.call.CallNode;
import com.oracle.graal.python.nodes.object.GetDictFromGlobalsNode;
import com.oracle.graal.python.nodes.statement.AbstractImportNode;
import com.oracle.truffle.api.dsl.Cached;
import com.oracle.truffle.api.dsl.Specialization;
import com.oracle.truffle.api.frame.VirtualFrame;
import com.oracle.truffle.api.profiles.ConditionProfile;
import com.oracle.truffle.api.strings.TruffleString;

/**
 * Equivalent of CPython's {@code PyImport_Import}.
 */
public abstract class PyImportImport extends PNodeWithState {

    private static final TruffleString T_LEVEL = tsLiteral("level");
    private static final TruffleString T_FROMLIST = tsLiteral("fromlist");

    public abstract Object execute(VirtualFrame frame, Object name);

    @Specialization
    Object doGeneric(VirtualFrame frame, Object moduleName,
                    @Cached ConditionProfile noGlobalsProfile,
                    @Cached ConditionProfile dictBuiltinsProfile,
                    @Cached PyImportGetModule importGetModule,
                    @Cached PyObjectGetItem getItemNode,
                    @Cached PyObjectGetAttr getAttrNode,
                    @Cached CallNode callNode,
                    @Cached AbstractImportNode.PyImportImportModuleLevelObject importModuleLevelObject,
                    @Cached PyEvalGetGlobals getGlobals,
                    @Cached GetDictFromGlobalsNode getDictFromGlobals) {
        // Get the builtins from current globals
        Object globals = getGlobals.execute(frame);
        Object builtins;
        if (noGlobalsProfile.profile(globals != null)) {
            builtins = getItemNode.execute(frame, getDictFromGlobals.execute(globals), T___BUILTINS__);
        } else {
            // No globals -- use standard builtins, and fake globals
            builtins = importModuleLevelObject.execute(frame, getContext(), T_BUILTINS, null, null, 0);
            globals = factory().createDict(new PKeyword[]{new PKeyword(T___BUILTINS__, builtins)});
        }

        // Get the __import__ function from the builtins
        Object importFunc;
        if (dictBuiltinsProfile.profile(builtins instanceof PDict)) {
            importFunc = getItemNode.execute(frame, builtins, T___IMPORT__);
        } else {
            importFunc = getAttrNode.execute(frame, builtins, T___IMPORT__);
        }

        // Call the __import__ function with the proper argument list Always use absolute import
        // here. Calling for side-effect of import.
        callNode.execute(importFunc, new Object[]{moduleName}, new PKeyword[]{
                        new PKeyword(T_GLOBALS, globals), new PKeyword(T_LOCALS, globals),
                        new PKeyword(T_FROMLIST, factory().createList()), new PKeyword(T_LEVEL, 0)
        });
        return importGetModule.execute(frame, moduleName);
    }
}
