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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
 *
 * Subject to the condition set forth below, permission is hereby granted to any
 * person obtaining a copy of this software, associated documentation and/or
 * data (collectively the "Software"), free of charge and under any and all
 * copyright rights in the Software, and any and all patent rights owned or
 * freely licensable by each licensor hereunder covering either (i) the
 * unmodified Software as contributed to or provided by such licensor, or (ii)
 * the Larger Works (as defined below), to deal in both
 *
 * (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,
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package com.oracle.truffle.sl.runtime;

import com.oracle.truffle.api.RootCallTarget;
import com.oracle.truffle.api.Truffle;
import com.oracle.truffle.sl.nodes.SLRootNode;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

/**
 * Manages the mapping from function names to {@link SLFunction function objects}.
 */
public final class SLFunctionRegistry {

    private final Map<String, SLFunction> functions = new HashMap<>();

    /**
     * Returns the canonical {@link SLFunction} object for the given name. If it does not exist yet,
     * it is created.
     */
    public SLFunction lookup(String name) {
        SLFunction result = functions.get(name);
        if (result == null) {
            result = new SLFunction(name);
            functions.put(name, result);
        }
        return result;
    }

    /**
     * Associates the {@link SLFunction} with the given name with the given implementation root
     * node. If the function did not exist before, it defines the function. If the function existed
     * before, it redefines the function and the old implementation is discarded.
     */
    public void register(String name, SLRootNode rootNode) {
        SLFunction function = lookup(name);
        RootCallTarget callTarget = Truffle.getRuntime().createCallTarget(rootNode);
        function.setCallTarget(callTarget);
    }

    /**
     * Returns the sorted list of all functions, for printing purposes only.
     */
    public List<SLFunction> getFunctions() {
        List<SLFunction> result = new ArrayList<>(functions.values());
        Collections.sort(result, new Comparator<SLFunction>() {
            public int compare(SLFunction f1, SLFunction f2) {
                return f1.toString().compareTo(f2.toString());
            }
        });
        return result;
    }
}