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module Catalog exposing (..)
import Browser
import Browser.Navigation as Nav
import Html exposing (..)
import Html.Attributes exposing (..)
import Html.Events exposing (..)
import Http
import Json.Decode as D
import Json.Encode as Encode
import Tuple exposing (..)
import Url
import Url.Parser as P exposing ((</>), Parser, int, oneOf, s, string)
import Utils exposing (..)
type Order
= Rating
| Price
type alias Product =
{ id : Int
, name : String
, kind : Maybe String
, price : Float
, description : Maybe String
, averageRating : Maybe Float
}
type alias Filters =
{ price : ( Float, Float )
, rating : ( Float, Float )
}
defaultFilters : Filters
defaultFilters =
Filters ( -1, 10000 ) ( 0, 5 )
type alias Model =
{ pageStatus : Status
, products : List Product
, filters : Filters
}
type Status
= Loading
| Loaded
| NotLoaded
type Msg
= ProductsLoaded (Result Http.Error (List Product))
| FetchProducts
| ChangePriceLower Float
| ChangePriceUpper Float
| ChangeRatingLower Float
| ChangeRatingUpper Float
init : Model
init =
Model NotLoaded [] defaultFilters
update : Msg -> Model -> ( Model, Cmd Msg )
update msg model =
case msg of
ProductsLoaded res ->
case res of
Ok s ->
( { model | products = s, pageStatus = Loaded }, Cmd.none )
Err e ->
let
_ =
Debug.log "error" e
in
( { model | pageStatus = NotLoaded }, Cmd.none )
FetchProducts ->
( { model | pageStatus = Loading }, fetchProducts )
ChangePriceLower v ->
let
fs =
model.filters
nfs =
{ fs | price = mapFirst (always v) fs.price }
in
( { model | filters = nfs }, Cmd.none )
ChangePriceUpper v ->
let
fs =
model.filters
nfs =
{ fs | price = mapSecond (always v) fs.price }
in
( { model | filters = nfs }, Cmd.none )
ChangeRatingLower v ->
let
fs =
model.filters
nfs =
{ fs | rating = mapFirst (always v) fs.rating }
in
( { model | filters = nfs }, Cmd.none )
ChangeRatingUpper v ->
let
fs =
model.filters
nfs =
{ fs | rating = mapSecond (always v) fs.rating }
in
( { model | filters = nfs }, Cmd.none )
decodeProduct : D.Decoder Product
decodeProduct =
D.map6 Product
(D.field "id" D.int)
(D.field "name" D.string)
(D.field "kind" (D.nullable D.string))
(D.field "price" D.float)
(D.field "description" (D.nullable D.string))
(D.field "average_rating" (D.nullable D.float))
decodeResponse : D.Decoder (List Product)
decodeResponse =
D.list decodeProduct
fetchProducts : Cmd Msg
fetchProducts =
let
_ =
Debug.log "err" "fetching products"
in
Http.get
{ url = "http://127.0.0.1:7878/product/catalog"
, expect = Http.expectJson ProductsLoaded decodeResponse
}
viewStatus : Status -> String
viewStatus s =
case s of
Loading ->
"Loading"
Loaded ->
"Ready!"
NotLoaded ->
"Not loaded ..."
viewProduct : Product -> Html Msg
viewProduct p =
div []
[ div [] [ text p.name ]
, div [] [ text <| Maybe.withDefault "" p.kind ]
, div [] [ text <| Maybe.withDefault "" p.description ]
, div [] [ text <| String.fromFloat p.price ]
, case p.averageRating of
Just v ->
text <| "Avg Rating: " ++ String.fromFloat v
Nothing ->
text "No Ratings"
, div [] [ a [ href ("/product/" ++ String.fromInt p.id) ] [ text "View Product" ] ]
]
viewFilters : Model -> Html Msg
viewFilters model =
let
priceRange =
range 0 50000 5000
ratingRange =
List.range 1 5
viewRange =
List.map (\i -> option [] [ text <| String.fromInt i ])
inp =
Maybe.withDefault 0 << String.toFloat
in
div []
[ div []
[ text "Price"
, select [ onInput (ChangePriceLower << inp) ] (viewRange priceRange)
, text "to"
, select [ onInput (ChangePriceUpper << inp) ] (viewRange priceRange)
]
, div []
[ text "Rating"
, select [ onInput (ChangeRatingLower << inp) ] (viewRange ratingRange)
, text "to"
, select [ onInput (ChangeRatingUpper << inp) ] (viewRange ratingRange)
]
]
filterProducts : Model -> List Product
filterProducts model =
model.products
|> List.filter (between model.filters.price << .price)
|> List.filter
(\p ->
p.averageRating
|> Maybe.withDefault 5.0
|> between model.filters.rating
)
view : Model -> Html Msg
view model =
case model.pageStatus of
Loading ->
div [] [ text <| viewStatus Loading ]
_ ->
div []
[ div [] [ viewFilters model ]
, ul []
(filterProducts model |> List.map viewProduct)
]
|
