/*
 * Copyright 1998-1999 Sun Microsystems, Inc.  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.  Sun designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
 * CA 95054 USA or visit www.sun.com if you need additional information or
 * have any questions.
 */

package com.sun.tools.jdi;

import com.sun.jdi.*;

import java.util.List;
import java.util.ArrayList;
import java.util.Map;
import java.util.Iterator;
import java.util.Collections;
import java.lang.ref.SoftReference;

public class InterfaceTypeImpl extends ReferenceTypeImpl
                               implements InterfaceType {

    private SoftReference<List<InterfaceType>> superinterfacesRef = null;

    protected InterfaceTypeImpl(VirtualMachine aVm,long aRef) {
        super(aVm, aRef);
    }

    public List<InterfaceType> superinterfaces() {
        List<InterfaceType> superinterfaces = (superinterfacesRef == null) ? null :
                                     superinterfacesRef.get();
        if (superinterfaces == null) {
            superinterfaces = getInterfaces();
            superinterfaces = Collections.unmodifiableList(superinterfaces);
            superinterfacesRef = new SoftReference<List<InterfaceType>>(superinterfaces);
        }
        return superinterfaces;
    }

    public List<InterfaceType> subinterfaces() {
        List<InterfaceType> subs = new ArrayList<InterfaceType>();
        for (ReferenceType refType : vm.allClasses()) {
            if (refType instanceof InterfaceType) {
                InterfaceType interfaze = (InterfaceType)refType;
                if (interfaze.isPrepared() && interfaze.superinterfaces().contains(this)) {
                    subs.add(interfaze);
                }
            }
        }
        return subs;
    }

    public List<ClassType> implementors() {
        List<ClassType> implementors = new ArrayList<ClassType>();
        for (ReferenceType refType : vm.allClasses()) {
            if (refType instanceof ClassType) {
                ClassType clazz = (ClassType)refType;
                if (clazz.isPrepared() && clazz.interfaces().contains(this)) {
                    implementors.add(clazz);
                }
            }
        }
        return implementors;
    }

    void addVisibleMethods(Map<String, Method> methodMap) {
        /*
         * Add methods from
         * parent types first, so that the methods in this class will
         * overwrite them in the hash table
         */

        for (InterfaceType interfaze : superinterfaces()) {
            ((InterfaceTypeImpl)interfaze).addVisibleMethods(methodMap);
        }

        addToMethodMap(methodMap, methods());
    }

    public List<Method> allMethods() {
        ArrayList<Method> list = new ArrayList<Method>(methods());

        /*
         * It's more efficient if don't do this
         * recursively.
         */
        for (InterfaceType interfaze : allSuperinterfaces()) {
            list.addAll(interfaze.methods());
        }

        return list;
    }

    List<InterfaceType> allSuperinterfaces() {
        ArrayList<InterfaceType> list = new ArrayList<InterfaceType>();
        addSuperinterfaces(list);
        return list;
    }

    void addSuperinterfaces(List<InterfaceType> list) {
        /*
         * This code is a little strange because it
         * builds the list with a more suitable order than the
         * depth-first approach a normal recursive solution would
         * take. Instead, all direct superinterfaces precede all
         * indirect ones.
         */

        /*
         * Get a list of direct superinterfaces that's not already in the
         * list being built.
         */
        List<InterfaceType> immediate = new ArrayList<InterfaceType>(superinterfaces());
        Iterator iter = immediate.iterator();
        while (iter.hasNext()) {
            InterfaceType interfaze = (InterfaceType)iter.next();
            if (list.contains(interfaze)) {
                iter.remove();
            }
        }

        /*
         * Add all new direct superinterfaces
         */
        list.addAll(immediate);

        /*
         * Recurse for all new direct superinterfaces.
         */
        iter = immediate.iterator();
        while (iter.hasNext()) {
            InterfaceTypeImpl interfaze = (InterfaceTypeImpl)iter.next();
            interfaze.addSuperinterfaces(list);
        }
    }

    boolean isAssignableTo(ReferenceType type) {

        // Exact match?
        if (this.equals(type)) {
            return true;
        } else {
            // Try superinterfaces.
            for (InterfaceType interfaze : superinterfaces()) {
                if (((InterfaceTypeImpl)interfaze).isAssignableTo(type)) {
                    return true;
                }
            }

            return false;
        }
    }

    List<InterfaceType> inheritedTypes() {
        return superinterfaces();
    }

    public boolean isInitialized() {
        return isPrepared();
    }

    public String toString() {
       return "interface " + name() + " (" + loaderString() + ")";
    }
}