module Main exposing (main)

import Browser
import Sort.Set exposing (Set)
import Html exposing (Html, div, input, label, p, text, h3)
import Html.Events exposing (onCheck)
import Html.Attributes exposing (class, type_, id)
import Modules exposing
  ( Module
  , all_modules
  , module_property
  , module_desc
  , module_sorter
  )

main: Program () Model Msg
main =
  Browser.sandbox { init = init, update = update, view = view }

-- INIT + Model


type alias Model =
  { enabled_modules : Set Module
  }

init : Model
init =
  { enabled_modules = Sort.Set.empty module_sorter
  }

-- UPDATE

type Msg
  = ToggleModule Module Bool

add_or_remove : Bool -> (a -> Set a -> Set a)
add_or_remove active =
  if active then
    Sort.Set.insert
  else
    Sort.Set.remove

update : Msg -> Model -> Model
update msg model =
  case msg of
    ToggleModule mod enabled ->
      { model | enabled_modules = add_or_remove enabled mod model.enabled_modules }

-- VIEW

view_module_button : Set Module -> Module -> Html Msg
view_module_button enabled mod =
  label
    (if Sort.Set.memberOf enabled mod then [class "active"] else [])
    [ input
      [ type_ "checkbox"
      , onCheck (ToggleModule mod)
      ] []
    , h3 [] [ text (module_property .name mod) ]
    , p [] (module_desc mod)
    ]

view : Model -> Html Msg
view model =
  div [id "elm-area"] (
      all_modules
        |> List.map (view_module_button model.enabled_modules)
  )