-module(atproto_codegen@plugin).
-compile([no_auto_import, nowarn_unused_vars, nowarn_unused_function, nowarn_nomatch, inline]).
-define(FILEPATH, "src/atproto_codegen/plugin.gleam").
-export([run/4, assemble/2]).
-export_type([output_file/0, codegen_error/0, plugin_context/0, plugin/0]).

-if(?OTP_RELEASE >= 27).
-define(MODULEDOC(Str), -moduledoc(Str)).
-define(DOC(Str), -doc(Str)).
-else.
-define(MODULEDOC(Str), -compile([])).
-define(DOC(Str), -compile([])).
-endif.

?MODULEDOC(
    " Minimal plugin host.\n"
    "\n"
    " A `Plugin` receives a `PluginContext` (the config, the decoded lexicon\n"
    " docs, the lowered view, and every upstream plugin's own output so far)\n"
    " and returns the `OutputFile`s it contributes. An `OutputFile.parts` is\n"
    " not a whole file: it is that plugin's ordered contribution, one entry\n"
    " per `lower.CodecUnit` in the module (see `lower.codec_units`). Plugins\n"
    " that cover the same units (today: `types` and `decode-json`, one def or\n"
    " synthesized union per unit) therefore produce equal-length `parts` lists\n"
    " for the same path.\n"
    "\n"
    " `run` executes the registry in dependency order (a plugin runs after\n"
    " everything in its `depends_on`) and hands each plugin the outputs placed\n"
    " so far, keyed by plugin name. `assemble` then merges, for a given path,\n"
    " the named plugins' `parts` lists by zipping them position for position\n"
    " in the caller-supplied order and joining the result with a blank line:\n"
    " this is what reproduces the original emitter's interleaving of a def's\n"
    " type/fields/encoder with its decoder, and a union's type/encoder with\n"
    " its decoder, without either plugin knowing about the other's text.\n"
    "\n"
    " A plugin that owns an entire module instead of contributing per-unit\n"
    " `parts` emits a `WholeFile(path, content)` for that path: `assemble`\n"
    " writes its `content` verbatim, with no zipping and no blank-line joining.\n"
    " This is for a plugin (e.g. `xrpc-client`) whose output is one complete\n"
    " module (its own doc, imports, everything) that no other plugin\n"
    " interleaves with, rather than a per-`CodecUnit` slice of a shared module.\n"
    " Two collisions are rejected as `ConflictingWholeFile(path)`: a path\n"
    " claimed as `WholeFile` that also has `parts` from any plugin, and a path\n"
    " claimed as `WholeFile` by more than one plugin.\n"
    "\n"
    " Order resolution is a static, dependency-respecting placement: it is not\n"
    " a general topological sort with cycle diagnostics, just enough to catch\n"
    " an unknown dependency name or a cycle across the handful of plugins this\n"
    " package registers.\n"
).

-type output_file() :: {output_file, binary(), list(binary())} |
    {whole_file, binary(), binary()}.

-type codegen_error() :: {unknown_dependency, binary(), binary()} |
    {unresolved_order, list(binary())} |
    {mismatched_sections, binary()} |
    {conflicting_whole_file, binary()} |
    {plugin_failure, binary(), binary()}.

-type plugin_context() :: {plugin_context,
        atproto_codegen@config:config(),
        list(atproto_lexicon@ast:lexicon_doc()),
        list(atproto_codegen@lower:flat_lexicon()),
        gleam@dict:dict(binary(), list(output_file()))}.

-type plugin() :: {plugin,
        binary(),
        list(binary()),
        fun((plugin_context()) -> {ok, list(output_file())} |
            {error, codegen_error()})}.

-file("src/atproto_codegen/plugin.gleam", 110).
-spec place(list(plugin()), list(plugin())) -> {ok, list(plugin())} |
    {error, codegen_error()}.
place(Remaining, Placed) ->
    case Remaining of
        [] ->
            {ok, lists:reverse(Placed)};

        _ ->
            Placed_names = gleam@list:map(
                Placed,
                fun(P) -> erlang:element(2, P) end
            ),
            {Ready, Rest} = gleam@list:partition(
                Remaining,
                fun(P@1) ->
                    gleam@list:all(
                        erlang:element(3, P@1),
                        fun(_capture) ->
                            gleam@list:contains(Placed_names, _capture)
                        end
                    )
                end
            ),
            case Ready of
                [] ->
                    {error,
                        {unresolved_order,
                            gleam@list:map(
                                Remaining,
                                fun(P@2) -> erlang:element(2, P@2) end
                            )}};

                _ ->
                    place(Rest, lists:append(lists:reverse(Ready), Placed))
            end
    end.

-file("src/atproto_codegen/plugin.gleam", 94).
-spec check_known_deps(list(plugin()), list(binary())) -> {ok, nil} |
    {error, codegen_error()}.
check_known_deps(Plugins, Names) ->
    _pipe = Plugins,
    gleam@list:try_each(
        _pipe,
        fun(Plugin) -> _pipe@1 = erlang:element(3, Plugin),
            gleam@list:try_each(
                _pipe@1,
                fun(Dep) -> case gleam@list:contains(Names, Dep) of
                        true ->
                            {ok, nil};

                        false ->
                            {error,
                                {unknown_dependency,
                                    erlang:element(2, Plugin),
                                    Dep}}
                    end end
            ) end
    ).

-file("src/atproto_codegen/plugin.gleam", 88).
-spec resolve_order(list(plugin())) -> {ok, list(plugin())} |
    {error, codegen_error()}.
resolve_order(Plugins) ->
    Names = gleam@list:map(Plugins, fun(P) -> erlang:element(2, P) end),
    gleam@result:'try'(
        check_known_deps(Plugins, Names),
        fun(_) -> place(Plugins, []) end
    ).

-file("src/atproto_codegen/plugin.gleam", 74).
-spec run(
    list(plugin()),
    atproto_codegen@config:config(),
    list(atproto_lexicon@ast:lexicon_doc()),
    list(atproto_codegen@lower:flat_lexicon())
) -> {ok, gleam@dict:dict(binary(), list(output_file()))} |
    {error, codegen_error()}.
run(Plugins, Cfg, Docs, Lexicons) ->
    gleam@result:'try'(
        resolve_order(Plugins),
        fun(Order) ->
            gleam@list:try_fold(
                Order,
                maps:new(),
                fun(Acc, Plugin) ->
                    Ctx = {plugin_context, Cfg, Docs, Lexicons, Acc},
                    gleam@result:'try'(
                        (erlang:element(4, Plugin))(Ctx),
                        fun(Outputs) ->
                            {ok,
                                gleam@dict:insert(
                                    Acc,
                                    erlang:element(2, Plugin),
                                    Outputs
                                )}
                        end
                    )
                end
            )
        end
    ).

-file("src/atproto_codegen/plugin.gleam", 227).
-spec zip_flat(list(list(binary()))) -> list(binary()).
zip_flat(Lists) ->
    case gleam@list:any(Lists, fun(L) -> L =:= [] end) of
        true ->
            [];

        false ->
            Heads = gleam@list:filter_map(Lists, fun gleam@list:first/1),
            Tails = gleam@list:map(
                Lists,
                fun(L@1) -> gleam@list:drop(L@1, 1) end
            ),
            lists:append(Heads, zip_flat(Tails))
    end.

-file("src/atproto_codegen/plugin.gleam", 210).
-spec interleave(binary(), list(list(binary()))) -> {ok, list(binary())} |
    {error, codegen_error()}.
interleave(Path, Sections) ->
    Non_empty = gleam@list:filter(Sections, fun(S) -> S /= [] end),
    case Non_empty of
        [] ->
            {ok, []};

        [First | Rest] ->
            Width = erlang:length(First),
            case gleam@list:all(
                Rest,
                fun(S@1) -> erlang:length(S@1) =:= Width end
            ) of
                false ->
                    {error, {mismatched_sections, Path}};

                true ->
                    {ok, zip_flat(Non_empty)}
            end
    end.

-file("src/atproto_codegen/plugin.gleam", 149).
-spec file_path(output_file()) -> binary().
file_path(File) ->
    case File of
        {output_file, Path, _} ->
            Path;

        {whole_file, Path@1, _} ->
            Path@1
    end.

-file("src/atproto_codegen/plugin.gleam", 192).
-spec assemble_parts(
    gleam@dict:dict(binary(), list(output_file())),
    list(binary()),
    binary()
) -> {ok, {binary(), binary()}} | {error, codegen_error()}.
assemble_parts(Outputs, Order, Path) ->
    gleam@result:'try'(
        gleam@list:try_map(
            Order,
            fun(Name) ->
                Files = begin
                    _pipe = gleam_stdlib:map_get(Outputs, Name),
                    gleam@result:unwrap(_pipe, [])
                end,
                case gleam@list:find(
                    Files,
                    fun(File) -> file_path(File) =:= Path end
                ) of
                    {ok, {output_file, _, Parts}} ->
                        {ok, Parts};

                    {ok, {whole_file, _, _}} ->
                        {ok, []};

                    {error, nil} ->
                        {ok, []}
                end
            end
        ),
        fun(Sections) ->
            gleam@result:'try'(
                interleave(Path, Sections),
                fun(Merged) ->
                    {ok, {Path, gleam@string:join(Merged, <<"\n\n"/utf8>>)}}
                end
            )
        end
    ).

-file("src/atproto_codegen/plugin.gleam", 156).
-spec assemble_path(
    gleam@dict:dict(binary(), list(output_file())),
    list(binary()),
    binary()
) -> {ok, {binary(), binary()}} | {error, codegen_error()}.
assemble_path(Outputs, Order, Path) ->
    Entries = gleam@list:flat_map(
        Order,
        fun(Name) -> _pipe = gleam_stdlib:map_get(Outputs, Name),
            _pipe@1 = gleam@result:unwrap(_pipe, []),
            gleam@list:filter(
                _pipe@1,
                fun(File) -> file_path(File) =:= Path end
            ) end
    ),
    Wholes = gleam@list:filter_map(Entries, fun(File@1) -> case File@1 of
                {whole_file, _, Content} ->
                    {ok, Content};

                {output_file, _, _} ->
                    {error, nil}
            end end),
    Has_parts = gleam@list:any(Entries, fun(File@2) -> case File@2 of
                {output_file, _, _} ->
                    true;

                {whole_file, _, _} ->
                    false
            end end),
    case Wholes of
        [] ->
            assemble_parts(Outputs, Order, Path);

        [Content@1] ->
            case Has_parts of
                true ->
                    {error, {conflicting_whole_file, Path}};

                false ->
                    {ok, {Path, Content@1}}
            end;

        _ ->
            {error, {conflicting_whole_file, Path}}
    end.

-file("src/atproto_codegen/plugin.gleam", 135).
?DOC(
    " Merge, for every path any of `order`'s plugins produced, their outputs\n"
    " into the final file text. A path claimed by a `WholeFile` yields its\n"
    " content verbatim; otherwise the plugins' `parts` lists are zipped\n"
    " position for position (in `order`) and joined the way the original\n"
    " emitter joined its chunks.\n"
).
-spec assemble(gleam@dict:dict(binary(), list(output_file())), list(binary())) -> {ok,
        list({binary(), binary()})} |
    {error, codegen_error()}.
assemble(Outputs, Order) ->
    _pipe = Order,
    _pipe@3 = gleam@list:flat_map(
        _pipe,
        fun(Name) -> _pipe@1 = gleam_stdlib:map_get(Outputs, Name),
            _pipe@2 = gleam@result:unwrap(_pipe@1, []),
            gleam@list:map(_pipe@2, fun file_path/1) end
    ),
    _pipe@4 = gleam@list:unique(_pipe@3),
    gleam@list:try_map(
        _pipe@4,
        fun(_capture) -> assemble_path(Outputs, Order, _capture) end
    ).