onasty @ 8f21410

module Effect exposing

    ( Effect, none, batch, map, toCmd, sendCmd, sendMsg

    , pushRoute, replaceRoute, pushRoutePath, replaceRoutePath, loadExternalUrl, back

    , sendApiRequest, sendToClipboard

    , signin, logout, refreshTokens, saveUser, clearUser

    )

{-|

@docs Effect, none, batch, map, toCmd, sendCmd, sendMsg

@docs pushRoute, replaceRoute, pushRoutePath, replaceRoutePath, loadExternalUrl, back

@docs sendApiRequest, sendToClipboard

@docs signin, logout, refreshTokens, saveUser, clearUser

-}

import Api

import Auth.User

import Browser.Navigation

import Data.Credentials exposing (Credentials)

import Data.Error

import Dict exposing (Dict)

import Http

import Json.Decode

import Json.Encode

import Ports

import Route

import Route.Path

import Shared.Model

import Shared.Msg

import Task

import Url exposing (Url)

type Effect msg

    = -- BASICS

      None

    | Batch (List (Effect msg))

    | SendCmd (Cmd msg)

      -- ROUTING

    | PushUrl String

    | ReplaceUrl String

    | LoadExternalUrl String

    | Back

      -- SHARED

    | SendSharedMsg Shared.Msg.Msg

    | SendToLocalStorage { key : String, value : Json.Encode.Value }

    | SendToClipboard String

    | SendApiRequest

        { endpoint : String

        , method : String

        , body : Http.Body

        , decoder : Json.Decode.Decoder msg

        , onHttpError : Api.Error -> msg

        }

-- BASICS

{-| Don't send any effect.

-}

none : Effect msg

none =

    None

{-| Send multiple effects at once.

-}

batch : List (Effect msg) -> Effect msg

batch =

    Batch

{-| Send a normal `Cmd msg` as an effect, something like `Http.get` or `Random.generate`.

-}

sendCmd : Cmd msg -> Effect msg

sendCmd =

    SendCmd

{-| Send a message as an effect. Useful when emitting events from UI components.

-}

sendMsg : msg -> Effect msg

sendMsg msg =

    Task.succeed msg

        |> Task.perform identity

        |> SendCmd

-- ROUTING

{-| Set the new route, and make the back button go back to the current route.

-}

pushRoute :

    { path : Route.Path.Path

    , query : Dict String String

    , hash : Maybe String

    }

    -> Effect msg

pushRoute route =

    PushUrl (Route.toString route)

{-| Same as `Effect.pushRoute`, but without `query` or `hash` support

-}

pushRoutePath : Route.Path.Path -> Effect msg

pushRoutePath path =

    PushUrl (Route.Path.toString path)

{-| Set the new route, but replace the previous one, so clicking the back

button **won't** go back to the previous route.

-}

replaceRoute :

    { path : Route.Path.Path

    , query : Dict String String

    , hash : Maybe String

    }

    -> Effect msg

replaceRoute route =

    ReplaceUrl (Route.toString route)

{-| Same as `Effect.replaceRoute`, but without `query` or `hash` support

-}

replaceRoutePath : Route.Path.Path -> Effect msg

replaceRoutePath path =

    ReplaceUrl (Route.Path.toString path)

{-| Redirect users to a new URL, somewhere external to your web application.

-}

loadExternalUrl : String -> Effect msg

loadExternalUrl =

    LoadExternalUrl

{-| Navigate back one page

-}

back : Effect msg

back =

    Back

-- SHARED

sendApiRequest :

    { endpoint : String

    , method : String

    , body : Http.Body

    , decoder : Json.Decode.Decoder value

    , onResponse : Result Api.Error value -> msg

    }

    -> Effect msg

sendApiRequest opts =

    SendApiRequest

        { endpoint = opts.endpoint

        , method = opts.method

        , body = opts.body

        , onHttpError = \e -> opts.onResponse (Err e)

        , decoder =

            opts.decoder

                |> Json.Decode.map Ok

                |> Json.Decode.map opts.onResponse

        }

sendToClipboard : String -> Effect msg

sendToClipboard text =

    SendToClipboard text

refreshTokens : Effect msg

refreshTokens =

    SendSharedMsg Shared.Msg.TriggerTokenRefresh

signin : Credentials -> Effect msg

signin credentials =

    SendSharedMsg (Shared.Msg.SignedIn credentials)

logout : Effect msg

logout =

    SendSharedMsg Shared.Msg.Logout

saveUser : String -> String -> Effect msg

saveUser accessToken refreshToken =

    batch

        [ SendToLocalStorage { key = "access_token", value = Json.Encode.string accessToken }

        , SendToLocalStorage { key = "refresh_token", value = Json.Encode.string refreshToken }

        ]

clearUser : Effect msg

clearUser =

    batch

        [ SendToLocalStorage { key = "access_token", value = Json.Encode.null }

        , SendToLocalStorage { key = "refresh_token", value = Json.Encode.null }

        ]

-- INTERNALS

map : (msg1 -> msg2) -> Effect msg1 -> Effect msg2

map fn effect =

    case effect of

        None ->

            None

        Batch list ->

            Batch (List.map (map fn) list)

        SendCmd cmd ->

            SendCmd (Cmd.map fn cmd)

        PushUrl url ->

            PushUrl url

        ReplaceUrl url ->

            ReplaceUrl url

        Back ->

            Back

        LoadExternalUrl url ->

            LoadExternalUrl url

        SendSharedMsg sharedMsg ->

            SendSharedMsg sharedMsg

        SendToLocalStorage options ->

            SendToLocalStorage options

        SendToClipboard text ->

            SendToClipboard text

        SendApiRequest opts ->

            SendApiRequest

                { endpoint = opts.endpoint

                , method = opts.method

                , body = opts.body

                , decoder = Json.Decode.map fn opts.decoder

                , onHttpError = \err -> fn (opts.onHttpError err)

                }

toCmd :

    { key : Browser.Navigation.Key

    , url : Url

    , shared : Shared.Model.Model

    , fromSharedMsg : Shared.Msg.Msg -> msg

    , batch : List msg -> msg

    , toCmd : msg -> Cmd msg

    }

    -> Effect msg

    -> Cmd msg

toCmd options effect =

    case effect of

        None ->

            Cmd.none

        Batch list ->

            Cmd.batch (List.map (toCmd options) list)

        SendCmd cmd ->

            cmd

        PushUrl url ->

            Browser.Navigation.pushUrl options.key url

        ReplaceUrl url ->

            Browser.Navigation.replaceUrl options.key url

        Back ->

            Browser.Navigation.back options.key 1

        LoadExternalUrl url ->

            Browser.Navigation.load url

        SendSharedMsg sharedMsg ->

            Task.succeed sharedMsg

                |> Task.perform options.fromSharedMsg

        SendToLocalStorage opts ->

            Ports.sendToLocalStorage opts

        SendToClipboard text ->

            Ports.sendToClipboard text

        SendApiRequest opts ->

            let

                headers : List Http.Header

                headers =

                    case options.shared.user of

                        Auth.User.SignedIn cred ->

                            if not (String.contains opts.endpoint "refresh-tokens") then

                                [ Http.header "Authorization" ("Bearer " ++ cred.accessToken) ]

                            else

                                []

                        _ ->

                            []

            in

            Http.request

                { method = opts.method

                , url = opts.endpoint

                , headers = headers

                , body = opts.body

                , expect =

                    Http.expectStringResponse

                        (\httpResult ->

                            case httpResult of

                                Ok msg ->

                                    msg

                                Err err ->

                                    opts.onHttpError err

                        )

                        (\resp -> httpResponseToCustomError opts.decoder resp)

                , timeout = Just (1000 * 60) -- 60 second timeout

                , tracker = Nothing

                }

httpResponseToCustomError : Json.Decode.Decoder msg -> Http.Response String -> Result Api.Error msg

httpResponseToCustomError decoder response =

    case response of

        Http.GoodStatus_ _ body ->

            case

                Json.Decode.decodeString decoder

                    (if String.isEmpty body then

                        "\"\""

                     else

                        body

                    )

            of

                Ok value ->

                    Ok value

                Err err ->

                    Err (Api.JsonDecodeError { message = "Failed to decode response", reason = err })

        Http.BadStatus_ { statusCode } body ->

            if String.isEmpty body then

                Err (Api.HttpError { message = "Unexpected empty response", reason = Http.BadStatus statusCode })

            else

                case Json.Decode.decodeString Data.Error.decode body of

                    Ok err ->

                        Err (Api.HttpError { message = err.message, reason = Http.BadStatus statusCode })

                    Err err ->

                        Err (Api.JsonDecodeError { message = "Failed to decode response", reason = err })

        Http.BadUrl_ url ->

            Err (Api.HttpError { message = "Unexpected URL format", reason = Http.BadUrl url })

        Http.Timeout_ ->

            Err (Api.HttpError { message = "Request timed out, please try again", reason = Http.Timeout })

        Http.NetworkError_ ->

            Err (Api.HttpError { message = "Could not connect, please try again", reason = Http.NetworkError })