/**
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements. See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership. The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License. You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied. See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */

package org.apache.cxf.tools.corba.processors.idl;

import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;

import antlr.collections.AST;

import org.apache.cxf.binding.corba.wsdl.CorbaConstants;

public final class Scope implements Comparable {

    private static final String SEPARATOR = ".";
    private List<String> scope;
    private Scope parent;
    
    public Scope() {
        scope = new ArrayList<String>();
        parent = this;
    }
    
    public Scope(String scopes, String separator) {
        java.util.StringTokenizer tokens = new java.util.StringTokenizer(scopes, separator);
        Scope rootScope = new Scope();
        Scope prevScope = rootScope.parent;
        scope = rootScope.scope;
        parent = this;
        while (tokens.hasMoreTokens()) {
            String token = tokens.nextToken();
            parent = prevScope;
            prevScope = new Scope(prevScope, token);
            scope.add(token);
        }
    }
    
    public Scope(Scope containingScope) {
        scope = new ArrayList<String>(containingScope.scope);
        parent = containingScope.getParent();
    }
    
    public Scope(Scope containingScope, String str) {
        scope = new ArrayList<String>(containingScope.scope);
        scope.add(str);
        parent = containingScope;
    }

    // This is used for interface inheritance
    public Scope(Scope containingScope, Scope prefixScope, String str) {
        scope = new ArrayList<String>(containingScope.scope);
        scope.addAll(prefixScope.scope);
        scope.add(str);
        parent = containingScope;
    }
    
    public Scope(Scope containingScope, AST node) {
        scope = new ArrayList<String>(containingScope.scope);
        if (node != null) { 
            scope.add(node.toString());
        }
        parent = containingScope;
    }
    
    public String tail() {
        int size = scope.size();
        if (size > 0) {
            return scope.get(size - 1);
        } else {
            return "";
        }
    }
    
    public Scope getParent() {
        return parent;
    }
    
    public String toString(String separator) {
        StringBuilder result = new StringBuilder();
        Iterator<String> it = scope.iterator();
        while (it.hasNext()) {
            result.append(it.next());
            if (it.hasNext()) {
                result.append(separator);
            }
        }
        return result.toString();
    }
    
    public String toString() {
        return toString(SEPARATOR);
    }

    public String toIDLRepositoryID() {
        StringBuilder result = new StringBuilder();
        result.append(CorbaConstants.REPO_STRING);
        result.append(toString("/"));
        result.append(CorbaConstants.IDL_VERSION);
        return result.toString();
    }

    public boolean equals(Object otherScope) {
        if (otherScope instanceof Scope) {
            return toString().equals(((Scope)otherScope).toString());   
        } else {
            return false;
        }
    }

    public int hashCode() {
        return toString().hashCode();
    }

    public int compareTo(Object otherScope) {
        if (otherScope == null) {
            throw new RuntimeException("Cannot compare a null object");
        }
        if (otherScope instanceof Scope) {
            return toString().compareTo(otherScope.toString());
        } else {
            throw new ClassCastException("Scope class expected but found "
                                         + otherScope.getClass().getName());
        }
    }
}
