module Pages.Internal.NotFoundReason exposing (ModuleContext, NotFoundReason(..), Payload, Record, document)

{-| Exposed for internal use only (used in generated code).

@docs ModuleContext, NotFoundReason, Payload, Record, document

-}

import Html exposing (Html)
import Html.Attributes as Attr
import Pages.Internal.RoutePattern exposing (RoutePattern)
import UrlPath exposing (UrlPath)


{-| -}
type alias ModuleContext =
    { moduleName : List String
    , routePattern : RoutePattern
    , matchedRouteParams : Record
    }


{-| -}
type alias Payload =
    { path : UrlPath
    , reason : NotFoundReason
    }


{-| -}
type alias Record =
    List ( String, String )


{-| -}
type NotFoundReason
    = NoMatchingRoute
    | NotPrerendered ModuleContext (List Record)
    | NotPrerenderedOrHandledByFallback ModuleContext (List Record)
    | UnhandledServerRoute ModuleContext


{-| -}
document :
    List RoutePattern
    -> Payload
    -> { title : String, body : List (Html msg) }
document pathPatterns payload =
    { title = "Page not found"
    , body =
        [ Html.div
            [ Attr.id "not-found-reason"
            , Attr.style "padding" "30px"
            ]
            (case payload.reason of
                NoMatchingRoute ->
                    [ Html.text <| "No route found for "
                    , Html.code []
                        [ Html.text
                            (payload.path
                                |> UrlPath.toAbsolute
                            )
                        ]
                    , Html.text " Did you mean to go to one of these routes:"
                    , Html.ul
                        [ Attr.style "padding-top" "30px"
                        ]
                        (pathPatterns
                            |> List.map
                                (\route ->
                                    Html.li
                                        [ Attr.style "list-style" "inside"
                                        ]
                                        [ route
                                            |> Pages.Internal.RoutePattern.view
                                        ]
                                )
                        )
                    ]

                NotPrerendered moduleContext routes ->
                    [ Html.h1 []
                        [ Html.text "Page Not Found"
                        ]
                    , Html.code []
                        [ Html.text
                            (payload.path
                                |> UrlPath.toAbsolute
                            )
                        ]
                    , Html.text " successfully matched the route "
                    , Html.br [] []
                    , Html.br [] []
                    , Html.code []
                        [ Pages.Internal.RoutePattern.view moduleContext.routePattern
                        ]
                    , Html.br [] []
                    , Html.br [] []
                    , Html.text " from the Route Module "
                    , Html.br [] []
                    , Html.br [] []
                    , Html.code []
                        [ Html.text (moduleName moduleContext)
                        ]
                    , prerenderedOptionsView moduleContext routes
                    ]

                _ ->
                    [ Html.text "Page not found"
                    , Html.text <| "TODO"
                    ]
            )
        ]
    }


prerenderedOptionsView : ModuleContext -> List Record -> Html msg
prerenderedOptionsView moduleContext routes =
    case routes of
        [] ->
            Html.div []
                [ Html.br [] []
                , Html.text "But this Page module has no pre-rendered routes! If you want to pre-render this page, add these "
                , Html.code [] [ Html.text "RouteParams" ]
                , Html.text " to the module's "
                , Html.code [] [ Html.text "routes" ]
                , Html.br [] []
                , Html.br [] []
                , Html.code
                    [ Attr.style "border-bottom" "dotted 2px"
                    , Attr.style "font-weight" "bold"
                    ]
                    [ Html.text <| recordToString moduleContext.matchedRouteParams
                    ]
                ]

        _ ->
            Html.div []
                [ Html.br [] []
                , Html.br [] []
                , Html.text " but these RouteParams were not present "
                , Html.br [] []
                , Html.br [] []
                , Html.code
                    [ Attr.style "border-bottom" "dotted 2px"
                    , Attr.style "font-weight" "bold"
                    ]
                    [ Html.text <| recordToString moduleContext.matchedRouteParams
                    ]
                , Html.br [] []
                , Html.br [] []
                , Html.text "The following RouteParams are pre-rendered:"
                , Html.ul
                    [ Attr.style "padding-top" "30px"
                    ]
                    (routes
                        |> List.map
                            (\record ->
                                Html.li
                                    [ Attr.style "list-style" "inside"
                                    ]
                                    [ --Html.a
                                      --    [-- Attr.href "/blog/extensible-markdown-parsing-in-elm"
                                      --     -- TODO get href data
                                      --    ]
                                      --    [
                                      Html.code
                                        []
                                        [ Html.text (recordToString record)
                                        ]

                                    --]
                                    ]
                            )
                    )
                , Html.br [] []
                , Html.br [] []
                , Html.p []
                    [ Html.text "Try changing "
                    , Html.code [] [ Html.text "routes" ]
                    , Html.text " in "
                    , Html.code [] [ Html.text (moduleName moduleContext) ]
                    , Html.text " to make sure it includes these "
                    , Html.code [] [ Html.text "RouteParams" ]
                    , Html.text "."
                    ]
                ]


recordToString : List ( String, String ) -> String
recordToString fields =
    "{ "
        ++ (fields
                |> List.map
                    (\( key, value ) ->
                        key ++ " = " ++ value
                    )
                |> String.join ", "
           )
        ++ " }"


moduleName : ModuleContext -> String
moduleName moduleContext =
    ("src" :: moduleContext.moduleName |> String.join "/") ++ ".elm"