starfuzz

-module(starfuzz@benchmark).
-compile([no_auto_import, nowarn_unused_vars, nowarn_unused_function, nowarn_nomatch, inline]).
-define(FILEPATH, "src/starfuzz/benchmark.gleam").
-export([now/0, new/0, add_algorithm/3, add_cases/2, with_iterations/2, run/1]).
-export_type(['case'/0, algorithm/0, benchmark_result/0, benchmark_builder/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(
    " A module providing performance benchmarking capabilities.\n"
    " Compares execution speeds of different similarity algorithms over a suite of test cases\n"
    " with target-independent millisecond timing.\n"
).

-type 'case'() :: {'case', binary(), binary(), binary()}.

-type algorithm() :: {algorithm, binary(), fun((binary(), binary()) -> float())}.

-type benchmark_result() :: {benchmark_result,
        binary(),
        binary(),
        integer(),
        integer()}.

-type benchmark_builder() :: {benchmark_builder,
        list(algorithm()),
        list('case'()),
        integer()}.

-file("src/starfuzz/benchmark.gleam", 11).
?DOC(
    " Returns the current system epoch time in milliseconds.\n"
    " Implemented via native Erlang and JavaScript FFI.\n"
).
-spec now() -> integer().
now() ->
    starfuzz_erl_ffi:now().

-file("src/starfuzz/benchmark.gleam", 50).
?DOC(" Creates a new BenchmarkBuilder with 1000 default iterations and no algorithms or cases.\n").
-spec new() -> benchmark_builder().
new() ->
    {benchmark_builder, [], [], 1000}.

-file("src/starfuzz/benchmark.gleam", 59).
?DOC(" Adds a named similarity algorithm to the suite.\n").
-spec add_algorithm(
    benchmark_builder(),
    binary(),
    fun((binary(), binary()) -> float())
) -> benchmark_builder().
add_algorithm(Builder, Name, Run) ->
    {benchmark_builder,
        [{algorithm, Name, Run} | erlang:element(2, Builder)],
        erlang:element(3, Builder),
        erlang:element(4, Builder)}.

-file("src/starfuzz/benchmark.gleam", 64).
?DOC(" Adds a list of test cases to the suite.\n").
-spec add_cases(benchmark_builder(), list('case'())) -> benchmark_builder().
add_cases(Builder, Cases) ->
    {benchmark_builder,
        erlang:element(2, Builder),
        lists:append(erlang:element(3, Builder), Cases),
        erlang:element(4, Builder)}.

-file("src/starfuzz/benchmark.gleam", 69).
?DOC(" Configures the number of iterations to execute for each test.\n").
-spec with_iterations(benchmark_builder(), integer()) -> benchmark_builder().
with_iterations(Builder, Iterations) ->
    {benchmark_builder,
        erlang:element(2, Builder),
        erlang:element(3, Builder),
        Iterations}.

-file("src/starfuzz/benchmark.gleam", 73).
-spec run_iterations(
    fun((binary(), binary()) -> float()),
    binary(),
    binary(),
    integer()
) -> nil.
run_iterations(Run_fn, Left, Right, Count) ->
    case Count =< 0 of
        true ->
            nil;

        false ->
            _ = Run_fn(Left, Right),
            run_iterations(Run_fn, Left, Right, Count - 1)
    end.

-file("src/starfuzz/benchmark.gleam", 84).
?DOC(" Runs the benchmark suite and returns the aggregated timing results.\n").
-spec run(benchmark_builder()) -> list(benchmark_result()).
run(Builder) ->
    gleam@list:flat_map(
        erlang:element(3, Builder),
        fun(Case_item) ->
            gleam@list:map(
                erlang:element(2, Builder),
                fun(Alg) ->
                    Start = starfuzz_erl_ffi:now(),
                    run_iterations(
                        erlang:element(3, Alg),
                        erlang:element(3, Case_item),
                        erlang:element(4, Case_item),
                        erlang:element(4, Builder)
                    ),
                    End = starfuzz_erl_ffi:now(),
                    {benchmark_result,
                        erlang:element(2, Alg),
                        erlang:element(2, Case_item),
                        erlang:element(4, Builder),
                        End - Start}
                end
            )
        end
    ).