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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * The Universal Permissive License (UPL), Version 1.0
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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
 * one is included with the Software each a "Larger Work" to which the Software
 * is contributed by such licensors),
 *
 * without restriction, including without limitation the rights to copy, create
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 * Software and the Larger Work(s), and to sublicense the foregoing rights on
 * either these or other terms.
 *
 * This license is subject to the following condition:
 *
 * The above copyright notice and either this complete permission notice or at a
 * minimum a reference to the UPL must be included in all copies or substantial
 * portions of the Software.
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 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
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package com.oracle.graal.python.builtins.objects.cext.capi;

import com.oracle.graal.python.builtins.objects.PythonAbstractObject;
import com.oracle.graal.python.builtins.objects.cext.capi.CExtNodes.AsCharPointerNode;
import com.oracle.graal.python.builtins.objects.cext.capi.CExtNodes.FromCharPointerNode;
import com.oracle.graal.python.builtins.objects.cext.capi.CExtNodes.GetNativeNullNode;
import com.oracle.graal.python.builtins.objects.cext.capi.CExtNodes.ToSulongNode;
import com.oracle.graal.python.builtins.objects.object.PythonObject;
import com.oracle.graal.python.nodes.PGuards;
import com.oracle.graal.python.nodes.SpecialMethodNames;
import com.oracle.graal.python.runtime.GilNode;
import com.oracle.truffle.api.CompilerDirectives;
import com.oracle.truffle.api.dsl.Cached;
import com.oracle.truffle.api.dsl.Cached.Exclusive;
import com.oracle.truffle.api.dsl.Cached.Shared;
import com.oracle.truffle.api.dsl.GenerateUncached;
import com.oracle.truffle.api.dsl.ImportStatic;
import com.oracle.truffle.api.dsl.Specialization;
import com.oracle.truffle.api.interop.InteropLibrary;
import com.oracle.truffle.api.interop.UnknownIdentifierException;
import com.oracle.truffle.api.interop.UnsupportedMessageException;
import com.oracle.truffle.api.library.CachedLibrary;
import com.oracle.truffle.api.library.ExportLibrary;
import com.oracle.truffle.api.library.ExportMessage;
import com.oracle.truffle.api.nodes.Node;
import com.oracle.truffle.llvm.spi.NativeTypeLibrary;

/**
 * Wraps a PythonObject to provide a native view with a shape like {@code PyMemberDef}.
 */
@ExportLibrary(InteropLibrary.class)
@ExportLibrary(value = NativeTypeLibrary.class, useForAOT = false)
@ImportStatic(SpecialMethodNames.class)
public class PyMemberDefWrapper extends PythonNativeWrapper {
    public static final String NAME = "name";
    public static final String DOC = "doc";

    public PyMemberDefWrapper(PythonObject delegate) {
        super(delegate);
    }

    @ExportMessage
    boolean hasMembers() {
        return true;
    }

    @ExportMessage
    protected boolean isMemberReadable(String member) {
        switch (member) {
            case NAME:
            case DOC:
                return true;
            default:
                return false;
        }
    }

    @ExportMessage
    protected Object getMembers(@SuppressWarnings("unused") boolean includeInternal) throws UnsupportedMessageException {
        throw UnsupportedMessageException.create();
    }

    @ExportMessage
    protected Object readMember(String member,
                    @CachedLibrary("this") PythonNativeWrapperLibrary lib,
                    @Exclusive @Cached ReadFieldNode readFieldNode,
                    @Exclusive @Cached GilNode gil) {
        boolean mustRelease = gil.acquire();
        try {
            return readFieldNode.execute(lib.getDelegate(this), member);
        } finally {
            gil.release(mustRelease);
        }
    }

    @ImportStatic({SpecialMethodNames.class, PyMemberDefWrapper.class})
    @GenerateUncached
    abstract static class ReadFieldNode extends Node {

        public abstract Object execute(Object delegate, String key);

        protected static boolean eq(String expected, String actual) {
            return expected.equals(actual);
        }

        @Specialization(guards = {"eq(NAME, key)"})
        static Object getName(PythonObject object, @SuppressWarnings("unused") String key,
                        @Shared("getAttrNode") @Cached PythonAbstractObject.PInteropGetAttributeNode getAttrNode,
                        @Shared("toSulongNode") @Cached ToSulongNode toSulongNode,
                        @Shared("asCharPointerNode") @Cached AsCharPointerNode asCharPointerNode,
                        @Shared("getNativeNullNode") @Cached GetNativeNullNode getNativeNullNode) {
            Object name = getAttrNode.execute(object, NAME);
            if (PGuards.isPNone(name)) {
                return toSulongNode.execute(getNativeNullNode.execute());
            } else {
                return asCharPointerNode.execute(name);
            }
        }

        @Specialization(guards = {"eq(DOC, key)"})
        static Object getDoc(PythonObject object, @SuppressWarnings("unused") String key,
                        @Shared("getAttrNode") @Cached PythonAbstractObject.PInteropGetAttributeNode getAttrNode,
                        @Shared("toSulongNode") @Cached ToSulongNode toSulongNode,
                        @Shared("asCharPointerNode") @Cached AsCharPointerNode asCharPointerNode,
                        @Shared("getNativeNullNode") @Cached GetNativeNullNode getNativeNullNode) {
            Object doc = getAttrNode.execute(object, DOC);
            if (PGuards.isPNone(doc)) {
                // CPython just returns the pointer of the original member def (i.e.
                // ((PyMemberDef*)obj)->doc )
                return toSulongNode.execute(getNativeNullNode.execute());
            } else {
                return asCharPointerNode.execute(doc);
            }
        }
    }

    @ExportMessage
    protected boolean isMemberModifiable(String member) {
        return member.equals(DOC);
    }

    @ExportMessage
    protected boolean isMemberInsertable(@SuppressWarnings("unused") String member) {
        return false;
    }

    @ExportMessage
    protected void writeMember(String member, Object value,
                    @CachedLibrary("this") PythonNativeWrapperLibrary lib,
                    @Cached PythonAbstractObject.PInteropSetAttributeNode setAttrNode,
                    @Exclusive @Cached FromCharPointerNode fromCharPointerNode,
                    @Exclusive @Cached GilNode gil) throws UnsupportedMessageException, UnknownIdentifierException {
        boolean mustRelease = gil.acquire();
        try {
            if (!DOC.equals(member)) {
                CompilerDirectives.transferToInterpreter();
                throw UnsupportedMessageException.create();
            }
            setAttrNode.execute(lib.getDelegate(this), member, fromCharPointerNode.execute(value));
        } finally {
            gil.release(mustRelease);
        }
    }

    @ExportMessage
    @SuppressWarnings("static-method")
    protected boolean hasNativeType() {
        // TODO implement native type
        return false;
    }

    @ExportMessage
    @SuppressWarnings("static-method")
    public Object getNativeType() {
        // TODO implement native type
        return null;
    }
}
