//============================================================================================================
// Microsoft Updater Application Block for .NET
//  http://msdn.microsoft.com/library/en-us/dnbda/html/updater.asp
// 
// SchemaValidator.cs
//
// Contains the implementation of the schema validator.
//
// For more information see the Updater Application Block Implementation Overview.
//
//============================================================================================================
// Copyright ?Microsoft Corporation.  All rights reserved.
// THIS CODE AND INFORMATION IS PROVIDED "AS IS" WITHOUT WARRANTY
// OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING BUT NOT
// LIMITED TO THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
// FITNESS FOR A PARTICULAR PURPOSE.
//============================================================================================================

using System;
using System.Collections;
using System.IO;
using System.Xml;
using System.Xml.Schema;

namespace Microsoft.ApplicationBlocks.Updater.Utilities
{
 /// <summary>
 /// Helper class to perform schema validations.
 /// </summary>
 public sealed class SchemaValidator
 {
  #region Private members
       
  /// <summary>
  /// The schemas that will be used for validation.
  /// </summary>
  private ArrayList schemas = new ArrayList(2);

  /// <summary>
  /// The errors detected during the validation.
  /// </summary>
  private ArrayList errors = new ArrayList(5);

  /// <summary>
  /// Whether the document is valid or not.
  /// </summary>
  private bool isValid;

  #endregion

  #region Constructors

  /// <summary>
  /// Creates an instance of the SchemaValidator using the document and the schemas.
  /// </summary>
  /// <param name="document">The document to validate.</param>
  /// <param name="schemas">A list of schemas to validate the document against.</param>
  public SchemaValidator( string document, params Stream[] schemas )
  {
   this.schemas.Add( document );
   foreach(Stream s in schemas)
   {
    this.schemas.Add( s );
   }
   isValid = true;
  }

  #endregion

  #region Public members

  /// <summary>
  /// Validates the document and returns the result of the validation.
  /// </summary>
  /// <returns><c>true</c> if the document have succeeded the validation, otherwise <c>false</c>.</returns>
  public bool Validate()
  {
   errors.Clear();
   XmlValidatingReader vr = null;
   object doc = schemas[0];
   if ( doc is Stream)
   {
    vr = new XmlValidatingReader( (Stream)doc, XmlNodeType.Element, null );
   }
   else if ( doc is String )
   {
    vr = new XmlValidatingReader( (string)doc, XmlNodeType.Element, null );
   }