module CacheSim.View exposing (..)
import CacheSim.Raw exposing (..)
import CacheSim.Model exposing (..)
import Html exposing (Html, input, text, div, label, span, h2, h3)
import Html.Attributes exposing (type_, class, value, for, classList, disabled)
import Html.Events exposing (onInput, onClick)

optionalButton : Bool -> String -> Msg -> Html Msg
optionalButton e s m =
    let
        events = if e then [ onClick m ] else  [ disabled (not e) ]
    in
        input ([ type_ "button", value s ] ++ events) []

button : String -> Msg -> Html Msg
button s m = input [ type_ "button", onClick m, value s] []

buttonWrapper : List (Html Msg) -> Html Msg
buttonWrapper = div [ class "button-wrapper" ]

labeledInput : String -> String -> (String -> Msg) -> Html Msg
labeledInput s val f =
    div [ class "input-group" ]
        [ span [] [ text s ]
        , input [ value val, type_ "text", onInput f ] []
        ]

viewRawCacheModel : Int -> RawCacheModel -> Html Msg
viewRawCacheModel level rcm =
    let
        updateBlockSize s cm = { cm | blockSize = s}
        updateSetCount s cm = { cm | setCount = s}
        updateSetSize s cm = { cm | setSize = s}
        wrapUpdate f s = ChangeRawModel level (f s)

        deleteButton = button "Delete" (DeleteRawModel level)

        params = div [ class "cache-model-params" ]
            [ labeledInput "Block size" rcm.blockSize (wrapUpdate updateBlockSize)
            , labeledInput "Set count" rcm.setCount (wrapUpdate updateSetCount)
            , labeledInput "Set size" rcm.setSize (wrapUpdate updateSetSize)
            ]
    in
        div [ class "cache-model" ]
            [ h3 [] [ text <| "L" ++ String.fromInt (level + 1) ++ " Cache" ]
            , buttonWrapper [ deleteButton ]
            , params
            ]

viewRawCacheModelHierarchy : RawCacheModelHierarchy -> Html Msg
viewRawCacheModelHierarchy rcmh =
    let
        models = div [ class "cache-model-levels" ] 
            <|List.indexedMap viewRawCacheModel rcmh
        translationResult = Result.andThen validateCacheModelHierarchy
            <| translateRawCacheModelHierarchy rcmh
        isValid =
            case translationResult of
                Ok _ -> True
                Err _ -> False
        errorHtml =
            case translationResult of
                Ok _ -> viewError True ""
                Err e -> viewError False e
        
        newButton = button "Add level" CreateRawModel
        useButton = case translationResult of
            Ok cmh -> optionalButton True "Use hierarchy" (UseHierarchy <| Just cmh)
            Err _ -> optionalButton False "Use hierarchy" (UseHierarchy Nothing)
    in
        div [ class "cache-model-hierarchy" ]
            [ h2 [] [ text "Cache hierarchy" ]
            , errorHtml
            , buttonWrapper [ newButton, useButton ]
            , models
            ]

viewError : Bool -> String -> Html Msg
viewError hide e = span [ classList [ ("hidden", hide) ] ] [ text e ]

viewBase : Model -> Html Msg
viewBase m =
    div [] [ viewRawCacheModelHierarchy m.rawHierarchy ]