Compose, edit and send E-Mail

[cyril]

Hi

I need some generell advice on how to solve my requirements.

I imagine a canvas app with a screen like this:

• Generally speaking: the app should compose an e-mail out of a combination of SharePoint data and static rich-texts depending on the combination out of 3 Dropdowns
• This text should be previewed and edited (if needed)
• Send Mail via smtp with credentials depending on the user

I have three task which I don't know how to get started:

1. Static text "library": Where is a good place to store the static texts? 
2. Compose the rich-text: The text has to be composed out of a combination of SharePoint data and static rich-texts depending on the combination out of the 3 DropDowns
   How could I achieve that?
3. The smtp credentials are different for every user. Where is a good place to store them on an individual basis? How can I get the credentials for the current user?

Thanks for any suggestions