-module(viva_tensor@core@error).
-compile([no_auto_import, nowarn_unused_vars, nowarn_unused_function, nowarn_nomatch, inline]).
-define(FILEPATH, "src/viva_tensor/core/error.gleam").
-export([shape_to_string/1, to_string/1]).
-export_type([tensor_error/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(false).

-type tensor_error() :: {shape_mismatch, list(integer()), list(integer())} |
    {invalid_shape, binary()} |
    {dimension_error, binary()} |
    {broadcast_error, list(integer()), list(integer())} |
    {index_out_of_bounds, integer(), integer()} |
    {dtype_error, binary()} |
    {axis_out_of_bounds, binary(), integer(), integer()} |
    {rank_mismatch, binary(), integer(), list(integer())} |
    {operand_shape_mismatch, binary(), binary(), binary(), list(integer())} |
    {slice_arity_mismatch, list(integer()), list(integer()), list(integer())} |
    {backend_mismatch, binary(), binary(), binary(), binary()} |
    {nif_not_loaded, binary()}.

-file("src/viva_tensor/core/error.gleam", 193).
?DOC(false).
-spec shape_to_string(list(integer())) -> binary().
shape_to_string(Shape) ->
    <<<<"["/utf8,
            (gleam@string:join(
                gleam@list:map(Shape, fun erlang:integer_to_binary/1),
                <<", "/utf8>>
            ))/binary>>/binary,
        "]"/utf8>>.

-file("src/viva_tensor/core/error.gleam", 113).
?DOC(false).
-spec to_string(tensor_error()) -> binary().
to_string(Error) ->
    case Error of
        {shape_mismatch, Expected, Got} ->
            <<<<<<"Shape mismatch: expected "/utf8,
                        (shape_to_string(Expected))/binary>>/binary,
                    ", got "/utf8>>/binary,
                (shape_to_string(Got))/binary>>;

        {invalid_shape, Reason} ->
            <<"Invalid shape: "/utf8, Reason/binary>>;

        {dimension_error, Reason@1} ->
            <<"Dimension error: "/utf8, Reason@1/binary>>;

        {broadcast_error, A, B} ->
            <<<<<<"Cannot broadcast shapes "/utf8, (shape_to_string(A))/binary>>/binary,
                    " and "/utf8>>/binary,
                (shape_to_string(B))/binary>>;

        {index_out_of_bounds, Index, Size} ->
            <<<<<<"Index "/utf8, (erlang:integer_to_binary(Index))/binary>>/binary,
                    " out of bounds for size "/utf8>>/binary,
                (erlang:integer_to_binary(Size))/binary>>;

        {dtype_error, Reason@2} ->
            <<"Dtype error: "/utf8, Reason@2/binary>>;

        {axis_out_of_bounds, Operation, Axis, Rank} ->
            <<<<<<<<<<<<<<Operation/binary, ": axis "/utf8>>/binary,
                                    (erlang:integer_to_binary(Axis))/binary>>/binary,
                                " is out of bounds for tensor of rank "/utf8>>/binary,
                            (erlang:integer_to_binary(Rank))/binary>>/binary,
                        " (valid: 0.."/utf8>>/binary,
                    (erlang:integer_to_binary(Rank - 1))/binary>>/binary,
                ")"/utf8>>;

        {rank_mismatch, Operation@1, Expected_rank, Got_shape} ->
            <<<<<<<<<<<<Operation@1/binary, " requires a "/utf8>>/binary,
                                (erlang:integer_to_binary(Expected_rank))/binary>>/binary,
                            "D tensor, got rank "/utf8>>/binary,
                        (erlang:integer_to_binary(erlang:length(Got_shape)))/binary>>/binary,
                    " with shape "/utf8>>/binary,
                (shape_to_string(Got_shape))/binary>>;

        {operand_shape_mismatch, Operation@2, Operand, Expected@1, Got@1} ->
            <<<<<<<<<<<<Operation@2/binary, ": "/utf8>>/binary, Operand/binary>>/binary,
                            " has shape "/utf8>>/binary,
                        (shape_to_string(Got@1))/binary>>/binary,
                    ", expected "/utf8>>/binary,
                Expected@1/binary>>;

        {slice_arity_mismatch, Tensor_shape, Start, Lengths} ->
            <<<<<<<<<<<<<<"slice: start and length must have rank "/utf8,
                                        (erlang:integer_to_binary(
                                            erlang:length(Tensor_shape)
                                        ))/binary>>/binary,
                                    " (tensor shape "/utf8>>/binary,
                                (shape_to_string(Tensor_shape))/binary>>/binary,
                            "); got start="/utf8>>/binary,
                        (shape_to_string(Start))/binary>>/binary,
                    ", length="/utf8>>/binary,
                (shape_to_string(Lengths))/binary>>;

        {backend_mismatch, Operation@3, Out, Lhs, Rhs} ->
            <<<<<<<<<<<<Operation@3/binary, ": backend mismatch — out="/utf8>>/binary,
                                Out/binary>>/binary,
                            ", lhs="/utf8>>/binary,
                        Lhs/binary>>/binary,
                    ", rhs="/utf8>>/binary,
                Rhs/binary>>;

        {nif_not_loaded, Operation@4} ->
            <<Operation@4/binary,
                ": native NIF library not loaded (build with `make zig` or `gleam build` after configuring the Zig toolchain)"/utf8>>
    end.