I have a large custom ecommerce engine that is currently using a SQL Server database (stored procedures handling most data tasks), a WCF middle-tier (handling business logic), and an MVC front-end site (that has no knowledge of any database). Our need for a content management system is increasing rapidly and I'm trying to figure out the best way to implement one, considering our very taxed development resources.
My first thought it to simply have two websites, an Orchard CMS site and our e-commerce site. I could setup some type of request routing that would send URLs for catalog browsing and cart functions to the ecommerce site, while other URLs get handled by the Orchard site. I would have to have a couple of modules (or widgets) built within the Orchard site that would display things like the cart summary that appears in the heading of each page. This seems like the easiest method of handling this, even if it is short-term.
My other thought is to have the site completely built using Orchard. This would require porting our ecommerce logic into modules. This seems like it would be one hell of a task. All of our work is done via web services, so if a user goes to a specific category URL, the site would call a web service and pass some variables (customer ID, category, etc). The web service would return the categories, products and prices for that customer - which would then be displayed on the screen.
Lastly, an even more complex version of the last option would be to actually store the products in Orchard, so that editable fields (description, meta tags, etc) would be managed through the Orchard CMS. This would require major changes to (or absorption of) our WCF middle-tier. This seems like it would be almost impossible, but may allow better handling of more media down the road (photos, videos, MSDS sheets, product literature, etc).
What are your thoughts so far, between these three models.