Is there a transactional email service with these features?

I'm looking for a transactional email service where I can basically do the following..

Steps:

1. Online email designer where I can design email templates.
2. The templates have some sort of variables or conditional logic where it inputs data that I send via JSON. This needs to include an ability to loop over arrays. For example if I send an array of order items, it needs to create a table row for each.
3. Sends the email to the address I pass along when making the api call.