module Default where

import Missing
import Demographics

input injury : {
    action   : Option String
  , location : String
  , severity : Double
  }

is_head : String -> Bool
is_head l =
  l == "head"

max_group : Element b -> Aggregate a -> Aggregate (Possibly b)
max_group k e =
  group fold (k, e) = (group k in e)
  in max_by e k

feature actioned_damage =
  from injury
    in filter let Some act = action
    in group act
    in sum severity

feature age =
  from age
    in newest value

feature is_head =
  from injury
    in is_head (newest location)

feature any_head =
  from injury
    in any (is_head location)

feature sum_severity =
  from injury
    in sum severity

feature any_ea =
  from injury
    in any (grepl "ea" location)

feature empty =
  from injury
    in seq missing 0

feature head_damage =
  from injury
    in filter is_head location
    in sum severity

feature worst_injured =
  from injury
    in max_group location (sum severity)

feature most_injured =
  from injury
    in max_group location (count severity)

feature sd_injury =
  from injury
    in sd severity

feature mean_injury =
  from injury
    in mean severity

feature injury_blah =
  from injury
    in filter location == "head" || (location == "arm" && is_some action)
    in sum severity

feature mean_day_of_week =
  from injury
    in let
      tau =
        2 * pi
      dow =
        tau / 7 * double (mod (days time) 7)
      m =
        (circular_stats dow).mean
    in
      m / tau * 7

feature days_in_location =
  from injury
    in days_in location time now