module CacheSim.Update exposing (..)
import CacheSim.Model exposing (..)
import CacheSim.Hierarchy exposing (..)
import CacheSim.Raw exposing (..)
import CacheSim.IntMap exposing (..)
import CacheSim.AccessView exposing (..)

updateChangeRawModel : Int -> (RawCacheModel -> RawCacheModel) -> Model -> (Model, Cmd Msg)
updateChangeRawModel l f m =
    let
        newModel = { m | rawHierarchy = intMapUpdate l f m.rawHierarchy }
        cmd = Cmd.none
    in
        (newModel, cmd)

updateCreateRawModel : Model -> (Model, Cmd Msg)
updateCreateRawModel m =
    let
        freshRawModel = { blockSize = "", setCount = "", setSize = "" }
        newModel = { m | rawHierarchy = m.rawHierarchy ++ [ freshRawModel ] }
        cmd = Cmd.none
    in
        (newModel, cmd)
 
updateDeleteRawModel : Int -> Model -> (Model, Cmd Msg)
updateDeleteRawModel l m =
    let
        newModel = { m | rawHierarchy = intMapDelete l m.rawHierarchy }
        cmd = Cmd.none
    in
        (newModel, cmd)

updateUseHierarchy : Maybe CacheModelHierarchy -> Model -> (Model, Cmd Msg)
updateUseHierarchy cmh m =
    let
        newModel = { m | hierarchy = Maybe.map freshCacheHierarchy cmh }
        cmd = Cmd.none
    in
        (newModel, cmd)

updateAccess : Int -> Model -> (Model, Cmd Msg)
updateAccess i m =
    let
        accessResult = Maybe.andThen (Result.toMaybe << accessCacheHierarchy i) m.hierarchy
        newModel = { m | accessView = Maybe.map (\ar -> (ar, Down 0)) accessResult }
        cmd = Cmd.none
    in
        (newModel, cmd)

updateAccessViewForward : Model -> (Model, Cmd Msg)
updateAccessViewForward m =
    let
        afterStep = Maybe.map accessViewForward m.accessView
        replaceHierarchy avs h = List.map .output avs ++ List.drop (List.length avs) h
        (newHierarchy, newAccessView) =
            case afterStep of
                Just (avs, Done) -> (Maybe.map (replaceHierarchy avs) m.hierarchy, Nothing)
                as_ -> (m.hierarchy, as_)
        newModel = { m | accessView = newAccessView, hierarchy = newHierarchy }
        cmd = Cmd.none
    in
        (newModel, cmd)

updateAccessViewBack : Model -> (Model, Cmd Msg)
updateAccessViewBack m =
    let
        afterStep = Maybe.map accessViewBack m.accessView
        newModel = { m | accessView = afterStep }
        cmd = Cmd.none
    in
        (newModel, cmd)