Show node if exists, else show node creation form

Question

I would like to setup an environment where each of my users will be creating a node every day. I know all of my users won't be able to log in every day and they will want to check what they added on past days. I figured the best way to accomplish adding past days & displaying created content would be checking the url and returning either the node (if they have created one) or the node/add form if they have not.

For example, user 1234 navigates to: url = example.com/user/1234/2011/09/10

If they have a node created with a date field set to this day it would show the node. If not, it returns the node/add form with a hidden field set to the date in the url (easy, I can take care of that).

My first thought was panels/page manager, but I don't see a way to check if a node is created based on a date structure, if it can be accomplished I am all ears. If you think another solution is better... I am all ears!

EDIT: It has been brought to my attention that my original question overlooked a node type. I might have more than one, and I could see this being useful for other people so lets say for arguments sake that the url looks like this:

example.com/user/1234/[node-type]/2011/09/10

Answer 1

I ended up getting this to work with views, date and some custom code. Basically I created a page view that with a conditional filter for a post date in YYYYMMDD format (a default argument provided by date), if one didn't exist I added some code in the "No Results" field that would load the node creation form with basically:

$form = node_add(arg(0));
print drupal_render($form);

So a url of /story/20110915 would show the story from that date if it existed, otherwise it would show the node/add form for the story content type.

In the final product I actually had the view load an .inc file from my custom module in the "No Results" field (also much faster than editing the view every time while developing). But I think this gets the basic point across.

Sorry @ram4nd if I made it seem like I didn't want to write code, I just was looking for the best approach. So far this seems like it is pretty solid.