/**
 * 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.helpers;

import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
import javax.xml.XMLConstants;
import javax.xml.namespace.NamespaceContext;

import org.w3c.dom.Node;

public  final class MapNamespaceContext implements NamespaceContext {
    private Map<String, String> namespaces = new HashMap<String, String>();
    private Node targetNode;

    public MapNamespaceContext() {
        super();
    }

    public MapNamespaceContext(final Map<String, String> ns) {
        this();
        this.namespaces = ns;
    }

    public MapNamespaceContext(final Node node) {
        this();
        this.targetNode = node;
    }

    public void setTargetNode(final Node node) {
        this.targetNode = node;
    }

    public void addNamespace(final String prefix, final String namespaceURI) {
        this.namespaces.put(prefix, namespaceURI);
    }

    public void addNamespaces(final Map<String, String> ns) {
        this.namespaces.putAll(ns);
    }

    public String getNamespaceURI(String prefix) {
        if (null == prefix) {
            throw new IllegalArgumentException("Null prefix to getNamespaceURI");
        }
        if (XMLConstants.XML_NS_PREFIX.equals(prefix)) {
            return XMLConstants.XML_NS_URI;
        }
        if (XMLConstants.XMLNS_ATTRIBUTE.equals(prefix)) {
            return XMLConstants.XMLNS_ATTRIBUTE_NS_URI;
        }
        // if we have a target node, facts-on-the-ground in its parent tree take precedence.
        if (targetNode != null) {
            String uri = DOMUtils.getNamespace(targetNode, prefix);
            if (uri != null) {
                return uri;
            }
            
        }
        return namespaces.get(prefix);
    }

    public String getPrefix(String namespaceURI) {
        if (namespaceURI == null) {
            throw new IllegalArgumentException("Null namespace to getPrefix");
        }
        if (XMLConstants.XML_NS_URI.equals(namespaceURI)) {
            return XMLConstants.XML_NS_PREFIX;
        }
        if (XMLConstants.XMLNS_ATTRIBUTE_NS_URI.equals(namespaceURI)) {
            return XMLConstants.XMLNS_ATTRIBUTE;
        }

        for (Map.Entry<String, String> e : namespaces.entrySet()) {
            if (e.getValue().equals(namespaceURI)) {
                return e.getKey();
            }
        }
        return null;
    }

    public Iterator<String> getPrefixes(String namespaceURI) {
        return null;
    }

    public Map<String, String> getUsedNamespaces() {
        return namespaces;
    }
}
