Valid FA username/directory name structure

[skylerbunny]

Although not an issue persay, the following should help in being able to determine what 'a valid inbound FA username is', when parsed, and what the translated name that belongs in a URL should be. Feel free to edit this if additional discoveries are made for your own use!

An FA username can have 1-50 characters maximum. A mortal person can only create 3-50, but accounts exist with 1 or 2 that still should be ALLOWED to be mapped.

Alphanumeric characters are normal, granting that uppercase is forced to lowercase in dirnames.

Table below shows discovered special characters in the wild, and if stripped as part of a dirname.
_ Y

• N
  ~ N
  . N
  [ N
  ] N
  ^ N (Becomes %5E)

Interesting cases:
David_the_Ultimate becomes davidtheultimate
Denny-the-Nidorina becomes denny-the-nidorina
DJWally becomes djwally
.VulpesRex. becomes .vulpesrex.
^69 becomes %5E69
[Cookies] becomes [cookies]

Possible leading "type" characters found in the wild: ! ~ ∞ @
! (banned)
~ (standard user)
∞ (deceased user)
@ (admin user)