A (Mostly) Declarative Framework for Building Simple WPF-based Wizards

/*
* Olbert.Utilities.Misc
* miscellaneous items for simplifying .NET programming
* Copyright (C) 2011  Mark A. Olbert
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as published 
* by the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program 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 for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Reflection;
using System.Collections.ObjectModel;
using System.Collections;
using System.Text.RegularExpressions;
using System.IO;
using ICSharpCode.SharpZipLib.Zip;

namespace Olbert.Utilities
{
    /// <summary>
    /// a class, derived from ResourceDirectory, which defines a virtual ResourceDirectory representing
    /// a zip file archive within an SourceAssembly.
    /// </summary>
    public class ResourceZipFile : ResourceDirectory
    {
        private ZipInputStream zipStream;

        /// <summary>
        /// Initializes an instance and assigns it to a ResourceDirectory object. Parses the contents
        /// of the zip file resource in the SourceAssembly and loads the resulting hierarchy into the
        /// Children property.
        /// </summary>
        /// <param name="parent">the ResourceDirectory to which the object belongs</param>
        /// <param name="name">the name of the ResourceDirectory, which must be unique within the
        /// owning ResourceDirectory</param>
        public ResourceZipFile( ResourceDirectory parent, string name )
            : base(parent, name)
        {
            zipStream = new ZipInputStream(this.Stream);

            ParseZipFile();
        }

        /// <summary>
        /// Initializes an instance and assigns it to a ResourceDirectory object.
        /// <para>This constructor is intended to be called internally when the zip file resource is
        /// parsed as part of the process creating the hierarchy of virtual ResourceFiles contained
        /// within the zip archive.</para>
        /// </summary>
        /// <param name="parent">the ResourceDirectory to which the object belongs</param>
        /// <param name="name">the name of the ResourceDirectory, which must be unique within the
        /// owning ResourceDirectory</param>
        /// <param name="zipStream">the ZipInputStream to the underlying zip file resource</param>
        public ResourceZipFile( ResourceDirectory parent, string name, ZipInputStream zipStream )
            : base(parent, name)
        {
            this.zipStream = zipStream;
        }

        /// <summary>
        /// Walks the file hierarchy in the zip file and creates a ResourceDirectory/ResourceFile hierarchy
        /// of the zip file contents. Creates ResourceSqlFile objects for archived files which have an
        /// 'sql' extension (case-insensitive). All other archived files are created as plain ResourceFile
        /// objects.
        /// </summary>
        protected void ParseZipFile()
        {
            MemoryStream curEntryStream;
            byte[] buffer = new byte[4096];
            int bytesRead = 0;

            ZipEntry curEntry = zipStream.GetNextEntry();

            Stack<ResourceDirectory> dirStack = new Stack<ResourceDirectory>();

            while( curEntry != null )
            {
                if( curEntry.IsDirectory )
                {
                    // it's a directory, so recurse into it and then add it to our children
                    ResourceZipFile subDir = new ResourceZipFile(this, curEntry.Name, zipStream);

                    Children.Add(subDir);
                }
                else
                {
                    // it's a plain old file, so extract its contents and add it to our children
                    curEntryStream = new MemoryStream();

                    do
                    {
                        bytesRead = zipStream.Read(buffer, 0, buffer.Length);

                        if( bytesRead > 0 ) curEntryStream.Write(buffer, 0, bytesRead);
                    } while( bytesRead > 0 );

                    // add the extracted file to the Children collection, checking to see
                    // if the ResourceFile that got created is actually a ResourceDirectory (which it
                    // will be if, for example, the extracted file is a zip file) because in that case we want
                    // to add the >>children<< of the newly-created object to the Children collection
                    ResourceFile newFile = FileTypes.Create(this, curEntry.Name, curEntryStream);
                    ResourceDirectory newDir = newFile as ResourceDirectory;

                    if( newDir == null ) Children.Add(newFile);
                    else Children.AddRange(newDir.Children);
                }
            }
        }
    }
}