/source/library/Interlace/AdornedPasteUp/Documents/ImageLinkManager.cs

#region Using Directives and Copyright Notice



// Copyright (c) 2007-2010, Computer Consultancy Pty Ltd

// All rights reserved.

// 

// Redistribution and use in source and binary forms, with or without

// modification, are permitted provided that the following conditions are met:

//     * Redistributions of source code must retain the above copyright

//       notice, this list of conditions and the following disclaimer.

//     * Redistributions in binary form must reproduce the above copyright

//       notice, this list of conditions and the following disclaimer in the

//       documentation and/or other materials provided with the distribution.

//     * Neither the name of the Computer Consultancy Pty Ltd nor the

//       names of its contributors may be used to endorse or promote products

//       derived from this software without specific prior written permission.

// 

// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 

// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 

// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 

// ARE DISCLAIMED. IN NO EVENT SHALL COMPUTER CONSULTANCY PTY LTD BE LIABLE 

// FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 

// DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR 

// SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER 

// CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 

// LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 

// OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH

// DAMAGE.



using System;

using System.Collections.Generic;

using System.ComponentModel;

using System.Text;



using Interlace.PropertyLists;



#endregion



namespace Interlace.AdornedPasteUp.Documents

{

    public class ImageLinkManager

    {

        Dictionary<ImageLink, int> _referenceCountByLink = new Dictionary<ImageLink, int>();



        public ImageLinkManager()

        {

        }



        internal ImageLinkManager(DocumentDeserializationContext context, PropertyDictionary managerDictionary)

        {

            PropertyDictionary imageLinks = managerDictionary.DictionaryFor("imageLinks");



            if (imageLinks == null) throw new InvalidOperationException("The image manager dictionary is missing the \"imageLinks\" key.");



            foreach (object key in imageLinks.Keys)

            {

                if (!(key is int)) throw new InvalidOperationException("The image links dictionary contains a non-integer key, which is not permitted.");



                int linkIndex = (int)key;



                PropertyDictionary imageDictionary = imageLinks.DictionaryFor(key);



                ImageLink link = new ImageLink(context, imageDictionary);



                _referenceCountByLink[link] = 0;

                context.ImageLinksByKey[linkIndex] = link;

            }

        }



        internal PropertyDictionary Serialize(DocumentSerializationContext context)

        {

            PropertyDictionary managerDictionary = PropertyDictionary.EmptyDictionary();



            PropertyDictionary imageLinks = PropertyDictionary.EmptyDictionary();

            managerDictionary.SetValueFor("imageLinks", imageLinks);



            int linkIndex = 1;



            foreach (ImageLink link in _referenceCountByLink.Keys)

            {

                context.ImageLinkKeys[link] = linkIndex;



                imageLinks.SetValueFor(linkIndex, link.Serialize(context));



                linkIndex++;

            }



            return managerDictionary;

        }



        public event EventHandler<LinkEventArgs> LinkAttached;

        public event EventHandler<LinkEventArgs> LinkDetached;



        public void Attach(ImageLink link)

        {

            if (_referenceCountByLink.ContainsKey(link))

            {

                _referenceCountByLink[link] = _referenceCountByLink[link] + 1;

            }

            else

            {

                _referenceCountByLink[link] = 1;



                if (LinkAttached != null) LinkAttached(this, new LinkEventArgs(this, link));

            }

        }



        public void Detach(ImageLink link)

        {

            if (!_referenceCountByLink.ContainsKey(link)) throw new InvalidOperationException();



            int newReferenceCount = _referenceCountByLink[link] - 1;



            if (newReferenceCount == 0)

            {

                _referenceCountByLink.Remove(link);



                if (LinkDetached != null) LinkDetached(this, new LinkEventArgs(this, link));

            }

            else

            {

                _referenceCountByLink[link] = newReferenceCount;

            }

        }



        public IEnumerable<ImageLink> Links

        {

            get

            {

                foreach (ImageLink link in _referenceCountByLink.Keys)

                {

                    yield return link;

                }

            }

        }

    }

}