-module(nakai@render).
-compile(no_auto_import).

-export([new/0, append/2, render_attr/1, render_attrs/1, render_children/1, render_doctype/1, render_node/1, render_root/1]).
-export_type([attr_render/1]).

-type attr_render(GPK) :: {attr_render,
                           gleam@string_builder:string_builder(),
                           list(nakai@render@state:event_state(GPK))}.

-spec new() -> attr_render(any()).
new() ->
    {attr_render, gleam@string_builder:new(), []}.

-spec append(attr_render(GPR), attr_render(GPR)) -> attr_render(GPR).
append(Before, Add) ->
    {attr_render,
     gleam@string_builder:append_builder(
         erlang:element(2, Before),
         erlang:element(2, Add)
     ),
     gleam@list:append(erlang:element(3, Before), erlang:element(3, Add))}.

-spec render_attr(nakai@html@attrs:attr(GPV)) -> attr_render(GPV).
render_attr(Attr) ->
    case Attr of
        {attr, Name, Value} ->
            _pipe = gleam@string_builder:from_strings(
                [<<" "/utf8>>, Name, <<"=\""/utf8>>, Value, <<"\""/utf8>>]
            ),
            {attr_render, _pipe, []};

        {event, Name@1, Action} ->
            Ref = <<"test-ref"/utf8>>,
            _pipe@1 = gleam@string_builder:from_strings(
                [<<" data-nakai-ref-"/utf8>>,
                 Name@1,
                 <<"=\""/utf8>>,
                 Ref,
                 <<"\""/utf8>>]
            ),
            {attr_render, _pipe@1, [{event_state, Name@1, Ref, Action}]}
    end.

-spec render_attrs(list(nakai@html@attrs:attr(GPY))) -> attr_render(GPY).
render_attrs(Attrs) ->
    _pipe = Attrs,
    _pipe@1 = gleam@list:map(_pipe, fun render_attr/1),
    gleam@list:fold(_pipe@1, new(), fun append/2).

-spec render_children(list(nakai@html:node_(GQC))) -> nakai@render@state:state(GQC).
render_children(Children) ->
    _pipe = Children,
    _pipe@1 = gleam@list:map(_pipe, fun render_node/1),
    gleam@list:fold(
        _pipe@1,
        nakai@render@state:new(),
        fun nakai@render@state:append/2
    ).

-spec render_doctype(nakai@html@doctype:doctype()) -> gleam@string_builder:string_builder().
render_doctype(Doctype) ->
    gleam@string_builder:from_strings(
        [<<"<!DOCTYPE "/utf8>>, erlang:element(2, Doctype), <<">"/utf8>>]
    ).

-spec render_node(nakai@html:node_(GQG)) -> nakai@render@state:state(GQG).
render_node(Tree) ->
    case Tree of
        {head, Children} ->
            _pipe = render_children(Children),
            nakai@render@state:headify(_pipe);

        {component, Factory} ->
            render_node(Factory());

        {fragment, Children@1} ->
            render_children(Children@1);

        {comment, Content} ->
            _pipe@1 = gleam@string_builder:from_strings(
                [<<"<!-- "/utf8>>, Content, <<" -->"/utf8>>]
            ),
            nakai@render@state:body_only(_pipe@1, []);

        {element, Tag, Attrs, Children@2} ->
            State = render_children(Children@2),
            Attr_render = render_attrs(Attrs),
            _pipe@2 = gleam@string_builder:concat(
                [gleam@string_builder:from_strings([<<"<"/utf8>>, Tag]),
                 erlang:element(2, Attr_render),
                 gleam@string_builder:from_string(<<">"/utf8>>),
                 erlang:element(3, State),
                 gleam@string_builder:from_strings(
                     [<<"</"/utf8>>, Tag, <<">"/utf8>>]
                 )]
            ),
            {state,
             erlang:element(2, State),
             _pipe@2,
             gleam@list:append(
                 erlang:element(4, State),
                 erlang:element(3, Attr_render)
             )};

        {leaf_element, Tag@1, Attrs@1} ->
            Attr_render@1 = render_attrs(Attrs@1),
            _pipe@3 = gleam@string_builder:concat(
                [gleam@string_builder:from_strings([<<"<"/utf8>>, Tag@1]),
                 erlang:element(2, Attr_render@1),
                 gleam@string_builder:from_string(<<" />"/utf8>>)]
            ),
            nakai@render@state:body_only(
                _pipe@3,
                erlang:element(3, Attr_render@1)
            );

        {text, Content@1} ->
            _pipe@4 = gleam@string_builder:from_string(Content@1),
            nakai@render@state:body_only(_pipe@4, []);

        nothing ->
            nakai@render@state:new()
    end.

-spec render_root(nakai@html:node_(any())) -> gleam@string_builder:string_builder().
render_root(Tree) ->
    Result = render_node(Tree),
    gleam@string_builder:concat(
        [gleam@string_builder:from_string(<<"<html>\n<head>"/utf8>>),
         erlang:element(2, Result),
         gleam@string_builder:from_string(<<"</head>\n<body>"/utf8>>),
         erlang:element(3, Result),
         generate_events_code(erlang:element(4, Result)),
         gleam@string_builder:from_string(<<"</body>\n</html>"/utf8>>)]
    ).

-spec generate_events_code(list(nakai@render@state:event_state(any()))) -> gleam@string_builder:string_builder().
generate_events_code(Events) ->
    case Events of
        [] ->
            gleam@string_builder:new();

        _@1 ->
            _pipe = Events,
            _pipe@2 = gleam@list:map(
                _pipe,
                fun(Event) ->
                    Selector = begin
                        _pipe@1 = gleam@string_builder:from_strings(
                            [<<"[data-nakai-ref-"/utf8>>,
                             erlang:element(2, Event),
                             <<"=\""/utf8>>,
                             erlang:element(3, Event),
                             <<"\"]"/utf8>>]
                        ),
                        gleam@string_builder:to_string(_pipe@1)
                    end,
                    gleam@string_builder:from_strings(
                        [<<"window.addEventListener(\"DOMContentLoaded\", function() {
          document.querySelector('"/utf8>>,
                         Selector,
                         <<"')
          .addEventListener('"/utf8>>,
                         erlang:element(2, Event),
                         <<"', () => console.log(\"doing the thing!!!\"));
          });\n"/utf8>>]
                    )
                end
            ),
            _pipe@3 = gleam@string_builder:concat(_pipe@2),
            _pipe@4 = gleam@string_builder:prepend(
                _pipe@3,
                <<"<script>\n"/utf8>>
            ),
            gleam@string_builder:append(_pipe@4, <<"\n</script>"/utf8>>)
    end.