/*

 * Copyright (c) 2010, 2014, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

package jdk.nashorn.internal.runtime;

import java.io.IOException;

import java.io.ObjectInputStream;

import java.io.ObjectOutputStream;

import java.io.Serializable;

import java.lang.invoke.MethodType;

import java.util.Map;

import jdk.nashorn.internal.codegen.CompileUnit;

import jdk.nashorn.internal.codegen.FunctionSignature;

import jdk.nashorn.internal.codegen.types.Type;

import jdk.nashorn.internal.ir.FunctionNode;

/**

 * Class that contains information allowing us to look up a method handle implementing a JavaScript function

 * from a generated class. This is used both for code coming from codegen and for persistent serialized code.

 */

public final class FunctionInitializer implements Serializable {

    private final String className;

    private final MethodType methodType;

    private final int flags;

    private transient Map<Integer, Type> invalidatedProgramPoints;

    private transient Class<?> code;

    private static final long serialVersionUID = -5420835725902966692L;

    /**

     * Constructor.

     *

     * @param functionNode the function node

     */

    public FunctionInitializer(final FunctionNode functionNode) {

        this(functionNode, null);

    }

    /**

     * Constructor.

     *

     * @param functionNode the function node

     * @param invalidatedProgramPoints invalidated program points

     */

    public FunctionInitializer(final FunctionNode functionNode, final Map<Integer, Type> invalidatedProgramPoints) {

        this.className  = functionNode.getCompileUnit().getUnitClassName();

        this.methodType = new FunctionSignature(functionNode).getMethodType();

        this.flags = functionNode.getFlags();

        this.invalidatedProgramPoints = invalidatedProgramPoints;

        final CompileUnit cu = functionNode.getCompileUnit();

        if (cu != null) {

            this.code = cu.getCode();

        }

        assert className != null;

    }

    /**

     * Returns the name of the class implementing the function.

     *

     * @return the class name

     */

    public String getClassName() {

        return className;

    }

    /**

     * Returns the type of the method implementing the function.

     *

     * @return the method type

     */

    public MethodType getMethodType() {

        return methodType;

    }

    /**

     * Returns the function flags.

     *

     * @return function flags

     */

    public int getFlags() {

        return flags;

    }

    /**

     * Returns the class implementing the function.

     *

     * @return the class

     */

    public Class<?> getCode() {

        return code;

    }

    /**

     * Set the class implementing the function

     * @param code the class

     */

    void setCode(final Class<?> code) {

        // Make sure code has not been set and has expected class name

        if (this.code != null) {

            throw new IllegalStateException("code already set");

        }

        assert className.equals(code.getTypeName().replace('.', '/')) : "unexpected class name";

        this.code = code;

    }

    /**

     * Returns the map of invalidated program points.

     *

     * @return invalidated program points

     */

    public Map<Integer, Type> getInvalidatedProgramPoints() {

        return invalidatedProgramPoints;

    }

    private void writeObject(final ObjectOutputStream out) throws IOException {

        out.defaultWriteObject();

        Type.writeTypeMap(invalidatedProgramPoints, out);

    }

    private void readObject(final ObjectInputStream in) throws IOException, ClassNotFoundException {

        in.defaultReadObject();

        invalidatedProgramPoints = Type.readTypeMap(in);

    }

}