-module(oaspec@generate).
-compile([no_auto_import, nowarn_unused_vars, nowarn_unused_function, nowarn_nomatch, inline]).
-define(FILEPATH, "src/oaspec/generate.gleam").
-export([validate_only/2, generate_all_files/1, generate/2]).
-export_type([generation_summary/0, validation_summary/0, generate_error/0, prepared_context/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.

-type generation_summary() :: {generation_summary,
        list(oaspec@codegen@context:generated_file()),
        binary(),
        list(oaspec@openapi@diagnostic:diagnostic())}.

-type validation_summary() :: {validation_summary,
        binary(),
        list(oaspec@openapi@diagnostic:diagnostic())}.

-type generate_error() :: {validation_errors,
        list(oaspec@openapi@diagnostic:diagnostic())}.

-type prepared_context() :: {prepared_context,
        oaspec@codegen@context:context(),
        binary(),
        list(oaspec@openapi@diagnostic:diagnostic())}.

-file("src/oaspec/generate.gleam", 47).
?DOC(
    " Shared pipeline: normalize → resolve → capability_check → hoist → dedup → validate.\n"
    " Returns a validated context with accumulated warnings, or errors.\n"
).
-spec prepare_context(
    oaspec@openapi@spec:open_api_spec(oaspec@openapi@spec:unresolved()),
    oaspec@config:config()
) -> {ok, prepared_context()} | {error, generate_error()}.
prepare_context(Spec, Cfg) ->
    Spec_title = <<<<(erlang:element(2, erlang:element(3, Spec)))/binary,
            " v"/utf8>>/binary,
        (erlang:element(4, erlang:element(3, Spec)))/binary>>,
    Spec@1 = oaspec@openapi@normalize:normalize(Spec),
    gleam@result:'try'(
        begin
            _pipe = oaspec@openapi@resolve:resolve(Spec@1),
            gleam@result:map_error(
                _pipe,
                fun(Errors) -> {validation_errors, Errors} end
            )
        end,
        fun(Spec@2) ->
            Capability_issues = begin
                _pipe@1 = oaspec@openapi@capability_check:check(Spec@2),
                oaspec@codegen@validate:filter_by_mode(
                    _pipe@1,
                    oaspec@config:mode(Cfg)
                )
            end,
            Capability_errors = oaspec@codegen@validate:errors_only(
                Capability_issues
            ),
            Capability_warnings = oaspec@codegen@validate:warnings_only(
                Capability_issues
            ),
            gleam@result:'try'(case gleam@list:is_empty(Capability_errors) of
                    false ->
                        {error, {validation_errors, Capability_errors}};

                    true ->
                        {ok, nil}
                end, fun(_) ->
                    Spec@3 = oaspec@openapi@hoist:hoist(Spec@2),
                    Spec@4 = oaspec@openapi@dedup:dedup(Spec@3),
                    Ctx = oaspec@codegen@context:new(Spec@4, Cfg),
                    Preserved_warnings = begin
                        _pipe@2 = oaspec@openapi@capability_check:check_preserved(
                            Ctx
                        ),
                        oaspec@openapi@diagnostic:filter_by_mode(
                            _pipe@2,
                            oaspec@config:mode(Cfg)
                        )
                    end,
                    Validation_issues = begin
                        _pipe@3 = oaspec@codegen@validate:validate(Ctx),
                        oaspec@codegen@validate:filter_by_mode(
                            _pipe@3,
                            oaspec@config:mode(Cfg)
                        )
                    end,
                    Blocking_errors = oaspec@codegen@validate:errors_only(
                        Validation_issues
                    ),
                    Validation_warnings = oaspec@codegen@validate:warnings_only(
                        Validation_issues
                    ),
                    gleam@result:'try'(
                        case gleam@list:is_empty(Blocking_errors) of
                            false ->
                                {error, {validation_errors, Blocking_errors}};

                            true ->
                                {ok, nil}
                        end,
                        fun(_) ->
                            Warnings = lists:append(
                                [Capability_warnings,
                                    Preserved_warnings,
                                    Validation_warnings]
                            ),
                            {ok, {prepared_context, Ctx, Spec_title, Warnings}}
                        end
                    )
                end)
        end
    ).

-file("src/oaspec/generate.gleam", 121).
?DOC(
    " Validation-only pipeline: parse → normalize → resolve → capability_check → hoist → dedup → validate.\n"
    " Runs the same checks as generate() but skips code generation and file writing.\n"
).
-spec validate_only(
    oaspec@openapi@spec:open_api_spec(oaspec@openapi@spec:unresolved()),
    oaspec@config:config()
) -> {ok, validation_summary()} | {error, generate_error()}.
validate_only(Spec, Cfg) ->
    gleam@result:'try'(
        prepare_context(Spec, Cfg),
        fun(Prepared) ->
            {ok,
                {validation_summary,
                    erlang:element(3, Prepared),
                    erlang:element(4, Prepared)}}
        end
    ).

-file("src/oaspec/generate.gleam", 153).
?DOC(
    " Generate shared files (types, decoders, encoders, guards).\n"
    "\n"
    " `middleware.gleam` used to be emitted here too, but its `Handler` shape\n"
    " did not actually compose with the generated client or server APIs (see\n"
    " issue #116). It is no longer part of the default generated surface;\n"
    " the `oaspec/codegen/middleware` module is kept only as a library-level\n"
    " helper for consumers who want to assemble their own middleware chain.\n"
).
-spec generate_shared(oaspec@codegen@context:context()) -> list(oaspec@codegen@context:generated_file()).
generate_shared(Ctx) ->
    Type_files = oaspec@codegen@types:generate(Ctx),
    Decoder_files = oaspec@codegen@decoders:generate(Ctx),
    Encoder_files = oaspec@codegen@encoders:generate(Ctx),
    Guard_files = oaspec@codegen@guards:generate(Ctx),
    lists:append([Type_files, Decoder_files, Encoder_files, Guard_files]).

-file("src/oaspec/generate.gleam", 133).
?DOC(" Pure file generation: produce all GeneratedFile values without any IO.\n").
-spec generate_all_files(oaspec@codegen@context:context()) -> list(oaspec@codegen@context:generated_file()).
generate_all_files(Ctx) ->
    Shared = generate_shared(Ctx),
    Server_files = case oaspec@config:mode(oaspec@codegen@context:config(Ctx)) of
        server ->
            oaspec@codegen@server:generate(Ctx);

        both ->
            oaspec@codegen@server:generate(Ctx);

        client ->
            []
    end,
    Client_files = case oaspec@config:mode(oaspec@codegen@context:config(Ctx)) of
        client ->
            oaspec@codegen@client:generate(Ctx);

        both ->
            oaspec@codegen@client:generate(Ctx);

        server ->
            []
    end,
    lists:append([Shared, Server_files, Client_files]).

-file("src/oaspec/generate.gleam", 106).
?DOC(
    " Pure generation pipeline: parse → normalize → resolve → capability_check → hoist → dedup → validate → codegen.\n"
    " Takes an already-parsed spec and config; returns generated files or errors.\n"
    " Does not perform IO — callers handle writing files and printing output.\n"
).
-spec generate(
    oaspec@openapi@spec:open_api_spec(oaspec@openapi@spec:unresolved()),
    oaspec@config:config()
) -> {ok, generation_summary()} | {error, generate_error()}.
generate(Spec, Cfg) ->
    gleam@result:'try'(
        prepare_context(Spec, Cfg),
        fun(Prepared) ->
            Files = generate_all_files(erlang:element(2, Prepared)),
            {ok,
                {generation_summary,
                    Files,
                    erlang:element(3, Prepared),
                    erlang:element(4, Prepared)}}
        end
    ).