//------------------------------------------------------------------------------
// <copyright file="XmlNamedNodeMap.cs" company="Microsoft">
//     Copyright (c) Microsoft Corporation.  All rights reserved.
// </copyright>                                                                
// <owner current="true" primary="true">Microsoft</owner>
//------------------------------------------------------------------------------

namespace System.Xml {
    using System.Collections;

    // Represents a collection of nodes that can be accessed by name or index.
    public partial class XmlNamedNodeMap : IEnumerable {
        internal XmlNode parent;
        internal SmallXmlNodeList nodes;

        internal XmlNamedNodeMap(XmlNode parent)
        {
            this.parent = parent;
        }

        // Retrieves a XmlNode specified by name.
        public virtual XmlNode GetNamedItem(String name) {
            int offset = FindNodeOffset(name);
            if (offset >= 0)
                return (XmlNode)nodes[offset];
            return null;
        }

        // Adds a XmlNode using its Name property
        public virtual XmlNode SetNamedItem(XmlNode node) {
            if ( node == null )
                return null;

            int offset = FindNodeOffset( node.LocalName, node.NamespaceURI );
            if (offset == -1) {
                AddNode( node );
                return null;
            }
            else {
                return ReplaceNodeAt( offset, node );
            }
        }

        // Removes the node specified by name.
        public virtual XmlNode RemoveNamedItem(String name) {
            int offset = FindNodeOffset(name);
            if (offset >= 0) {
                return RemoveNodeAt( offset );
            }
            return null;
        }

        // Gets the number of nodes in this XmlNamedNodeMap.
        public virtual int Count {
            get {
                return nodes.Count;
            }
        }

        // Retrieves the node at the specified index in this XmlNamedNodeMap.
        public virtual XmlNode Item(int index) {
            if (index < 0 || index >= nodes.Count)
                return null;
            try {
                return (XmlNode)nodes[index];
            } catch ( ArgumentOutOfRangeException ) {
                throw new IndexOutOfRangeException(Res.GetString(Res.Xdom_IndexOutOfRange));
            }
        }

        //
        // DOM Level 2
        //

        // Retrieves a node specified by LocalName and NamespaceURI.
        public virtual XmlNode GetNamedItem(String localName, String namespaceURI) {
            int offset = FindNodeOffset( localName, namespaceURI );
            if (offset >= 0)
                return (XmlNode)nodes[offset];
            return null;
        }

        // Removes a node specified by local name and namespace URI.
        public virtual XmlNode RemoveNamedItem(String localName, String namespaceURI) {
            int offset = FindNodeOffset( localName, namespaceURI );
            if (offset >= 0) {
                return RemoveNodeAt( offset );
            }
            return null;
        }

        public virtual IEnumerator GetEnumerator() {
            return nodes.GetEnumerator();
        }

        internal int FindNodeOffset( string name ) {
            int c = this.Count;
            for (int i = 0; i < c; i++) {
                XmlNode node = (XmlNode) nodes[i];

                if (name == node.Name)
                    return i;
            }

            return -1;
        }

        internal int FindNodeOffset( string localName, string namespaceURI ) {
            int c = this.Count;
            for (int i = 0; i < c; i++) {
                XmlNode node = (XmlNode) nodes[i];

                if (node.LocalName == localName && node.NamespaceURI == namespaceURI)
                    return i;
            }

            return -1;
        }

        internal virtual XmlNode AddNode( XmlNode node ) {
            XmlNode oldParent;
            if ( node.NodeType == XmlNodeType.Attribute )
                oldParent = ((XmlAttribute)node).OwnerElement;
            else
                oldParent = node.ParentNode;
            string nodeValue = node.Value;
            XmlNodeChangedEventArgs args = parent.GetEventArgs( node, oldParent, parent, nodeValue, nodeValue, XmlNodeChangedAction.Insert );

            if (args != null)
                parent.BeforeEvent( args );

            nodes.Add( node );
            node.SetParent( parent );

            if (args != null)
                parent.AfterEvent( args );

            return node;
        }

        internal virtual XmlNode AddNodeForLoad(XmlNode node, XmlDocument doc) {
            XmlNodeChangedEventArgs args = doc.GetInsertEventArgsForLoad(node, parent);
            if (args != null) {
                doc.BeforeEvent(args);
            }
            nodes.Add(node);
            node.SetParent(parent);
            if (args != null) {
                doc.AfterEvent(args);
            }
            return node;
        }

        internal virtual XmlNode RemoveNodeAt( int i ) {
            XmlNode oldNode = (XmlNode)nodes[i];

            string oldNodeValue = oldNode.Value;
            XmlNodeChangedEventArgs args = parent.GetEventArgs( oldNode, parent, null, oldNodeValue, oldNodeValue, XmlNodeChangedAction.Remove );

            if (args != null)
                parent.BeforeEvent( args );

            nodes.RemoveAt(i);
            oldNode.SetParent( null );

            if (args != null)
                parent.AfterEvent( args );

            return oldNode;
        }

        internal XmlNode ReplaceNodeAt( int i, XmlNode node ) {
            XmlNode oldNode = RemoveNodeAt( i );
            InsertNodeAt( i, node );
            return oldNode;
        }

        internal virtual XmlNode InsertNodeAt( int i, XmlNode node ) {
            XmlNode oldParent;
            if ( node.NodeType == XmlNodeType.Attribute )
                oldParent = ((XmlAttribute)node).OwnerElement;
            else
                oldParent = node.ParentNode;

            string nodeValue = node.Value;
            XmlNodeChangedEventArgs args = parent.GetEventArgs( node, oldParent, parent, nodeValue, nodeValue, XmlNodeChangedAction.Insert );

            if (args != null)
                parent.BeforeEvent( args );

            nodes.Insert( i, node );
            node.SetParent( parent );

            if (args != null)
                parent.AfterEvent( args );

            return node;
        }
    }
}