After using version 1.5 in the real world, I've realized it's time to make the solution more robust, with higher performance. The 1.5 implementation is so bad, in fact, that I'm not going to offer the source code as promised -- it just isn't release (even alpha) quality. As implemented, if the server goes down or there is a momentary network outage, I have to restart the client (the WCF channel faults and no longer functions). What I really need is a way to make the communication channel more fault tolerant. I can approach this several ways, but by drawing on the toolkits I know best, I have decided to use the Smart Client Software Factory as a base implementation framework for the product. This is probably overkill for what I'm doing, but I really like the automatic offline/online detection and the modular nature of the services layers.

Since we already have something resembling a UI, the next thing is to take a serious look at the business / data access layers. They're pretty co-mingled right now, and experts in the field tell me that isn't a good idea. For the Data Access layer, I see two different approaches: 1) Direct webservice access (like we've done in our previous examples) using the Disconnected Service Agent block provided by the SCSF, or 2) employing the services of 1) for real-time information (now playing) and handling the large volume of media library information via a local, cached data store, regularly updated via ADO.NET synchronization services.

Of course, 2) is my favorite, but we'll start with 1) and move to 2). The nice bit about the SCSF in this case is that changing the data access layer at a later time should have minimal impact on either the business layer or the UI. So long as the data access layer continues to implement the same service interface, the actual implementation shouldn't matter.

So, here goes. We'll start by downloading and installing the most recent version of SCSF, Guidance Automation Extensions (GAX), and Enterprise Library for VS2008.

With that out of the way, we start with a brand new smart client project with WPF UI components enabled. By default, if you want to enable WPF UI components, it creates a WinForms application that allows WPF parts to be hosted. I'm not sure I like this hybrid solution, and may look into using the techniques in the SCSFContrib CodePlex project to get a truly WPF application at the end of the day.

Here's the plan of attack:

1. Implement the Data Access layer as an online/offline fault tolerant service.
2. Implement some form of business layer using a yet-to-be-determined approach.
3. Drop in the existing front-row clone as a UI layer for the time being.
4. Implement a client-side cache for the media library (seldom changing) data.
5. Replace the UI with a purely WPF implementation, possibly using the SCSFContrib libraries.

Sounds simple. Rather than walking through the entire solution, I'll post the areas where I have problems and (possibly) some solutions to these problems.