An opaque type to hold the configuration value for a TOTP.

This is the value to store in your database, by calling toString

https://github.com/google/google-authenticator/wiki/Key-Uri-Format#algorithm

Attempt to return the expected OTP code at the given time.

Compare this value against the user input to verify if their OTP is correct.

Return the number of seconds the OTP from code is valid for

Attempt to parse a String representation of Key back into a Key value

Builds a Key value from the parameters

https://rootprojects.org/authenticator/

import Base32
import String.Extra
import TOTP.Algorithm
import TOTP


keyResult : Result String Key
keyResult =
    init
        { issuer = "ACME Co"
        , user = "[email protected]"
        , rawSecret = "HXDMVJECJJWSRB3HWIZR4IFUGFTMXBOZ"
            |> Base32.decode
            |> Result.map String.Extra.fromCodePoints
            |> Result.withDefault "<fail>"
        , outputLength = Just 6
        , periodSeconds = Just 30
        , algorithm = TOTP.Algorithm.SHA1
        }


-- expected String output
Result.map toString keyResult
--> Ok "otpauth://totp/ACME%20Co:[email protected]?secret=HXDMVJECJJWSRB3HWIZR4IFUGFTMXBOZ&issuer=ACME%20Co&algorithm=SHA1&digits=6&period=30"




-- toString and fromString are reversible
Result.map toString keyResult
|> Result.map fromString
--> Ok (Result.toMaybe keyResult)