Develop custom upload function in WordPress

We build webapplications in .NET (C#, MVC etc.) and interconnected for one of our customers a WordPress website to our webapp. What happens is that the customer goes to the WordPress website and then logs in. However, the customer does not directly log into the WordPress website. Instead the customer logs in on our webapplication through a page that is served in an iframe, after which the webapp logs in the user in WordPress using a general (shared) WordPress user. So to clarify; the users John and Karen both login through the WordPress website (iframe) on our webapp. Our webapp logs in both John and Karen on the WordPress website as 'Generic Customer'. What we would like to achieve is that both John and Karen can upload/delete files in WordPress. However the files need to be linked to the (webapp)username, not to the generic (shared) WordPress username. We do store the webapp username in the session object ( $_SESSION["cp_user"] ) so it is available in WordPress. With regard to the uploading, here is what we would like to achive. * A shortcode that we can put up on a page or post that inserts a file upload feature. The feature consists of a input field (text), a browse button and upload button. * A shortcode that we can put up on a page or post that inserts a table that shows the files the (webapp)user has uploaded. * Only documents with pdf extension are allowed to be uploaded * We need to be able to set a maximum file size limit. * The actual filename of the uploaded documents are to be renamed to the format webapp username-iso-datetime-version [login to view URL] So for example; if John uploads a document '[login to view URL]' the filename would be renamed to '[login to view URL] * The uploads will have to be placed in the /wp-content/uploads/cpdocs/ * The original filename is saved and shown to the user. To that end I think I need a table with stores the following data File ID, webapp username, original filename, stored filename, version number, show, date, time File ID [int] is for internal use webapp username [varchar] is in this example John or Karen original file name [varchar] is in this example [login to view URL] stored file name [varchar] is in this example [login to view URL] version number [int] is in this example 1 show [boolean] is in this example true, meaning that this is document has to be listed on the user page in WordPress, showing the user that he/she uploaded this document. date, time [date] that shows the date and time the file was uploaded. * The webapp users would also need to be able to remove their uploads, however, deleting means 'removing from eyesight' in this case. In other words, the show field value needs to be set to false. The renamed file that is stored on the webserver itself should not be removed. * The shortcode that shows the table of uploaded files needs to show all uploaded files to admins. That way an admin can easily see which user uploaded which files. We don't necessarily need a fancy plugin for this as long as it will function. It is ok to set limitations/filters in the code itself. We can add code to [login to view URL] etc. So basically what we primarily need to the above described functionality. Can you develop this for us and if so what would it cost? I'm looking forward to your answer. Kind regards, Remco