import Html exposing (Html, Attribute, div, h1, input, p, text)
import Html.Attributes exposing (checked, style, type_)
import Html.Events exposing (onClick)
import Html.Lazy exposing (lazy)
import Table exposing (defaultCustomizations)
import Time exposing (Time)



main =
  Html.program
    { init = init missionSights
    , update = update
    , view = view
    , subscriptions = \_ -> Sub.none
    }



-- MODEL


type alias Model =
  { sights : List Sight
  , tableState : Table.State
  }


init : List Sight -> ( Model, Cmd Msg )
init sights =
  let
    model =
      { sights = sights
      , tableState = Table.initialSort "Year"
      }
  in
    ( model, Cmd.none )



-- UPDATE


type Msg
  = ToggleSelected String
  | SetTableState Table.State


update : Msg -> Model -> ( Model, Cmd Msg )
update msg model =
  case msg of
    ToggleSelected name ->
      ( { model | sights = List.map (toggle name) model.sights }
      , Cmd.none
      )

    SetTableState newState ->
      ( { model | tableState = newState }
      , Cmd.none
      )


toggle : String -> Sight -> Sight
toggle name sight =
  if sight.name == name then
    { sight | selected = not sight.selected }

  else
    sight



-- VIEW


view : Model -> Html Msg
view { sights, tableState } =
  div []
    [ h1 [] [ text "Trip Planner" ]
    , lazy viewSummary sights
    , Table.view config tableState sights
    ]


viewSummary : List Sight -> Html msg
viewSummary allSights =
  case List.filter .selected allSights of
    [] ->
      p [] [ text "Click the sights you want to see on your trip!" ]

    sights ->
      let
        time =
          List.sum (List.map .time sights)

        price =
          List.sum (List.map .price sights)

        summary =
          "That is " ++ timeToString time ++ " of fun, costing $" ++ toString price
      in
        p [] [ text summary ]


timeToString : Time -> String
timeToString time =
  let
    hours =
      case floor (Time.inHours time) of
        0 -> ""
        1 -> "1 hour"
        n -> toString n ++ " hours"

    minutes =
      case rem (round (Time.inMinutes time)) 60 of
        0 -> ""
        1 -> "1 minute"
        n -> toString n ++ " minutes"
  in
    hours ++ " " ++ minutes



-- TABLE CONFIGURATION


config : Table.Config Sight Msg
config =
  Table.customConfig
    { toId = .name
    , toMsg = SetTableState
    , columns =
        [ checkboxColumn
        , Table.stringColumn "Name" .name
        , timeColumn
        , Table.floatColumn "Price" .price
        , Table.floatColumn "Rating" .rating
        ]
    , customizations =
        { defaultCustomizations | rowAttrs = toRowAttrs }
    }


toRowAttrs : Sight -> List (Attribute Msg)
toRowAttrs sight =
  [ onClick (ToggleSelected sight.name)
  , style [ ("background", if sight.selected then "#CEFAF8" else "white") ]
  ]


timeColumn : Table.Column Sight Msg
timeColumn =
  Table.customColumn
    { name = "Time"
    , viewData = timeToString << .time
    , sorter = Table.increasingOrDecreasingBy .time
    }


checkboxColumn : Table.Column Sight Msg
checkboxColumn =
  Table.veryCustomColumn
    { name = ""
    , viewData = viewCheckbox
    , sorter = Table.unsortable
    }


viewCheckbox : Sight -> Table.HtmlDetails Msg
viewCheckbox {selected} =
  Table.HtmlDetails []
    [ input [ type_ "checkbox", checked selected ] []
    ]



-- SIGHTS


type alias Sight =
  { name : String
  , time : Time
  , price : Float
  , rating : Float
  , selected : Bool
  }


missionSights : List Sight
missionSights =
  [ Sight "Eat a Burrito" (30 * Time.minute) 7 4.6 False
  , Sight "Buy drugs in Dolores park" Time.hour 20 4.8 False
  , Sight "Armory Tour" (1.5 * Time.hour) 27 4.5 False
  , Sight "Tartine Bakery" Time.hour 10 4.1 False
  , Sight "Have Brunch" (2 * Time.hour) 25 4.2 False
  , Sight "Get catcalled at BART" (5 * Time.minute) 0 1.6 False
  , Sight "Buy a painting at \"Stuff\"" (45 * Time.minute) 400 4.7 False
  , Sight "McDonalds at 24th" (20 * Time.minute) 5 2.8 False
  ]