/*

 * Copyright (c) 1996, 2006, 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 org.apidesign.bck2brwsr.emul;

import java.lang.reflect.Method;

import org.apidesign.bck2brwsr.core.JavaScriptBody;

/** Utilities to work on methods.

 *

 * @author Jaroslav Tulach <jtulach@netbeans.org>

 */

public abstract class MethodImpl {

    public static MethodImpl INSTANCE;

    static {

        try {

            Class.forName(Method.class.getName());

        } catch (ClassNotFoundException ex) {

            throw new IllegalStateException(ex);

        }

    }

    protected abstract Method create(Class<?> declaringClass, String name, Object data, String sig);

    //

    // bck2brwsr implementation

    //

    @JavaScriptBody(args = {"clazz", "prefix"},

        body = ""

        + "var c = clazz.cnstr.prototype;"

        + "var arr = new Array();\n"

        + "for (m in c) {\n"

        + "  if (m.indexOf(prefix) === 0) {\n"

        + "     arr.push(m);\n"

        + "     arr.push(c[m]);\n"

        + "  }"

        + "}\n"

        + "return arr;")

    private static native Object[] findMethodData(

        Class<?> clazz, String prefix);

    public static Method findMethod(

        Class<?> clazz, String name, Class<?>... parameterTypes) {

        Object[] data = findMethodData(clazz, name + "__");

        if (data.length == 0) {

            return null;

        }

        String sig = ((String) data[0]).substring(name.length() + 2);

        return INSTANCE.create(clazz, name, data[1], sig);

    }

    public static Method[] findMethods(Class<?> clazz, int mask) {

        Object[] namesAndData = findMethodData(clazz, "");

        int cnt = 0;

        for (int i = 0; i < namesAndData.length; i += 2) {

            String sig = (String) namesAndData[i];

            Object data = namesAndData[i + 1];

            int middle = sig.indexOf("__");

            if (middle == -1) {

                continue;

            }

            String name = sig.substring(0, middle);

            sig = sig.substring(middle + 2);

            final Method m = INSTANCE.create(clazz, name, data, sig);

            if ((m.getModifiers() & mask) == 0) {

                continue;

            }

            namesAndData[cnt++] = m;

        }

        Method[] arr = new Method[cnt];

        for (int i = 0; i < cnt; i++) {

            arr[i] = (Method) namesAndData[i];

        }

        return arr;

    }

}