-module(lightspeed@ops@failover_harness).
-compile([no_auto_import, nowarn_unused_vars, nowarn_unused_function, nowarn_nomatch, inline]).
-define(FILEPATH, "src/lightspeed/ops/failover_harness.gleam").
-export([run_scenario/1, run_matrix/0, scenario_label/1, pass_fail_label/1, signature/1, scenario/1, deterministic/1, outcomes/1, failed_scenarios/1, nondeterministic_failures/1, report_signature/1, snapshot_signature/0, snapshot_report_markdown/0]).
-export_type([scenario/0, scenario_outcome/0, report/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(" Deterministic failover certification harness for M27.\n").

-type scenario() :: supported_backends |
    ownership_fencing |
    crash_restart_failover |
    resume_policy_matrix |
    reconnect_continuity_slo.

-type scenario_outcome() :: {scenario_outcome,
        scenario(),
        boolean(),
        boolean(),
        binary()}.

-type report() :: {report, list(scenario_outcome()), integer(), integer()}.

-file("src/lightspeed/ops/failover_harness.gleam", 470).
-spec count_nondeterministic(list(scenario_outcome())) -> integer().
count_nondeterministic(Outcomes) ->
    case Outcomes of
        [] ->
            0;

        [Outcome | Rest] ->
            case erlang:element(4, Outcome) of
                true ->
                    count_nondeterministic(Rest);

                false ->
                    1 + count_nondeterministic(Rest)
            end
    end.

-file("src/lightspeed/ops/failover_harness.gleam", 459).
-spec count_failed(list(scenario_outcome())) -> integer().
count_failed(Outcomes) ->
    case Outcomes of
        [] ->
            0;

        [Outcome | Rest] ->
            case erlang:element(3, Outcome) of
                true ->
                    count_failed(Rest);

                false ->
                    1 + count_failed(Rest)
            end
    end.

-file("src/lightspeed/ops/failover_harness.gleam", 488).
-spec join_with(binary(), list(binary())) -> binary().
join_with(Separator, Values) ->
    case Values of
        [] ->
            <<""/utf8>>;

        [Value] ->
            Value;

        [Value@1 | Rest] ->
            <<<<Value@1/binary, Separator/binary>>/binary,
                (join_with(Separator, Rest))/binary>>
    end.

-file("src/lightspeed/ops/failover_harness.gleam", 449).
-spec entries_all_met(list({boolean(), binary()})) -> boolean().
entries_all_met(Entries) ->
    case Entries of
        [] ->
            true;

        [Entry | Rest] ->
            {Met, _} = Entry,
            Met andalso entries_all_met(Rest)
    end.

-file("src/lightspeed/ops/failover_harness.gleam", 360).
-spec evaluate_reconnect_continuity_slo() -> {boolean(), binary()}.
evaluate_reconnect_continuity_slo() ->
    Entries = gleam@list:map(
        lightspeed@cluster@durable_session:supported_backends(),
        fun(Backend) ->
            Base = begin
                _pipe = lightspeed@cluster@durable_session:start(
                    <<"s-4"/utf8>>,
                    <<"node-a"/utf8>>,
                    <<"/chat"/utf8>>,
                    Backend,
                    rehydrate,
                    0,
                    25,
                    1
                ),
                _pipe@1 = lightspeed@cluster@durable_session:append_counter_delta(
                    _pipe,
                    1,
                    2
                ),
                _pipe@2 = lightspeed@cluster@durable_session:append_counter_delta(
                    _pipe@1,
                    1,
                    3
                ),
                _pipe@3 = lightspeed@cluster@durable_session:append_counter_delta(
                    _pipe@2,
                    1,
                    4
                ),
                _pipe@4 = lightspeed@cluster@durable_session:crash(
                    _pipe@3,
                    <<"boom"/utf8>>
                ),
                lightspeed@cluster@durable_session:restart(_pipe@4, 200)
            end,
            Recovered = case lightspeed@cluster@durable_session:request_takeover(
                Base,
                <<"node-b"/utf8>>,
                2,
                lightspeed@cluster@durable_session:expected_token(
                    <<"s-4"/utf8>>,
                    <<"node-b"/utf8>>,
                    2
                ),
                210
            ) of
                {ok, Updated} ->
                    Updated;

                {error, _} ->
                    Base
            end,
            Reconnected = lightspeed@cluster@durable_session:reconnect(
                Recovered,
                rehydrate,
                <<"/chat"/utf8>>,
                220
            ),
            Continuity = lightspeed@cluster@durable_session:continuity_report(
                Reconnected,
                200,
                220
            ),
            {erlang:element(4, Continuity),
                <<<<(lightspeed@cluster@durable_session:backend_label(Backend))/binary,
                        ":"/utf8>>/binary,
                    (lightspeed@cluster@durable_session:continuity_signature(
                        Continuity
                    ))/binary>>}
        end
    ),
    Passed = entries_all_met(Entries),
    Signatures = gleam@list:map(
        Entries,
        fun(Entry) ->
            {_, Signature} = Entry,
            Signature
        end
    ),
    {Passed, join_with(<<";"/utf8>>, Signatures)}.

-file("src/lightspeed/ops/failover_harness.gleam", 322).
-spec evaluate_resume_policy_matrix() -> {boolean(), binary()}.
evaluate_resume_policy_matrix() ->
    Baseline = begin
        _pipe = lightspeed@cluster@durable_session:start(
            <<"s-3"/utf8>>,
            <<"node-a"/utf8>>,
            <<"/todos"/utf8>>,
            {journal_only, <<"journal"/utf8>>},
            resume,
            0,
            25,
            0
        ),
        lightspeed@cluster@durable_session:append_counter_delta(_pipe, 2, 6)
    end,
    Resumed = lightspeed@cluster@durable_session:reconnect(
        Baseline,
        resume,
        <<"/todos"/utf8>>,
        40
    ),
    Rehydrated = lightspeed@cluster@durable_session:reconnect(
        Baseline,
        rehydrate,
        <<"/todos"/utf8>>,
        40
    ),
    Remounted = lightspeed@cluster@durable_session:reconnect(
        Baseline,
        remount,
        <<"/todos"/utf8>>,
        40
    ),
    Resumed_counter = erlang:element(
        4,
        lightspeed@cluster@durable_session:snapshot(Resumed)
    ),
    Rehydrated_counter = erlang:element(
        4,
        lightspeed@cluster@durable_session:snapshot(Rehydrated)
    ),
    Remounted_counter = erlang:element(
        4,
        lightspeed@cluster@durable_session:snapshot(Remounted)
    ),
    Passed = ((Resumed_counter =:= 2) andalso (Rehydrated_counter =:= 2))
    andalso (Remounted_counter =:= 0),
    {Passed,
        <<<<<<<<<<"resume="/utf8,
                            (erlang:integer_to_binary(Resumed_counter))/binary>>/binary,
                        "|rehydrate="/utf8>>/binary,
                    (erlang:integer_to_binary(Rehydrated_counter))/binary>>/binary,
                "|remount="/utf8>>/binary,
            (erlang:integer_to_binary(Remounted_counter))/binary>>}.

-file("src/lightspeed/ops/failover_harness.gleam", 267).
-spec evaluate_crash_restart_failover() -> {boolean(), binary()}.
evaluate_crash_restart_failover() ->
    Durable = begin
        _pipe = lightspeed@cluster@durable_session:start(
            <<"s-2"/utf8>>,
            <<"node-a"/utf8>>,
            <<"/counter"/utf8>>,
            {snapshot_journal, <<"snap"/utf8>>, <<"journal"/utf8>>, 2},
            rehydrate,
            0,
            25,
            1
        ),
        _pipe@1 = lightspeed@cluster@durable_session:append_counter_delta(
            _pipe,
            3,
            5
        ),
        _pipe@2 = lightspeed@cluster@durable_session:crash(
            _pipe@1,
            <<"boom"/utf8>>
        ),
        lightspeed@cluster@durable_session:restart(_pipe@2, 100)
    end,
    Recovered = case lightspeed@cluster@durable_session:request_takeover(
        Durable,
        <<"node-b"/utf8>>,
        2,
        lightspeed@cluster@durable_session:expected_token(
            <<"s-2"/utf8>>,
            <<"node-b"/utf8>>,
            2
        ),
        110
    ) of
        {ok, Updated} ->
            Updated;

        {error, _} ->
            Durable
    end,
    Reconnected = lightspeed@cluster@durable_session:reconnect(
        Recovered,
        rehydrate,
        <<"/counter"/utf8>>,
        118
    ),
    Continuity = lightspeed@cluster@durable_session:continuity_report(
        Reconnected,
        100,
        118
    ),
    Snapshot = lightspeed@cluster@durable_session:snapshot(Reconnected),
    Passed = ((erlang:element(4, Snapshot) =:= 3) andalso (lightspeed@cluster@durable_session:lifecycle_label(
        erlang:element(5, Snapshot)
    )
    =:= <<"live"/utf8>>))
    andalso erlang:element(4, Continuity),
    {Passed,
        <<<<(lightspeed@cluster@durable_session:signature(Reconnected))/binary,
                "|continuity="/utf8>>/binary,
            (lightspeed@cluster@durable_session:continuity_signature(Continuity))/binary>>}.

-file("src/lightspeed/ops/failover_harness.gleam", 440).
-spec ownership_result_label(
    {ok, lightspeed@cluster@durable_session:durable_session()} |
        {error, lightspeed@cluster@durable_session:ownership_error()}
) -> binary().
ownership_result_label(Value) ->
    case Value of
        {ok, _} ->
            <<"ok"/utf8>>;

        {error, Error} ->
            lightspeed@cluster@durable_session:ownership_error_label(Error)
    end.

-file("src/lightspeed/ops/failover_harness.gleam", 194).
-spec evaluate_ownership_fencing() -> {boolean(), binary()}.
evaluate_ownership_fencing() ->
    Baseline = lightspeed@cluster@durable_session:start(
        <<"s-1"/utf8>>,
        <<"node-a"/utf8>>,
        <<"/counter"/utf8>>,
        {snapshot_journal, <<"snap"/utf8>>, <<"journal"/utf8>>, 2},
        rehydrate,
        0,
        25,
        1
    ),
    Takeover_token = lightspeed@cluster@durable_session:expected_token(
        <<"s-1"/utf8>>,
        <<"node-b"/utf8>>,
        2
    ),
    Takeover = lightspeed@cluster@durable_session:request_takeover(
        Baseline,
        <<"node-b"/utf8>>,
        2,
        Takeover_token,
        10
    ),
    {Takeover_label, Takeover_signature} = case Takeover of
        {ok, Updated} ->
            {<<"ok"/utf8>>,
                lightspeed@cluster@durable_session:fence_signature(
                    lightspeed@cluster@durable_session:fence(Updated)
                )};

        {error, Error} ->
            {lightspeed@cluster@durable_session:ownership_error_label(Error),
                <<"none"/utf8>>}
    end,
    Stale_label = case Takeover of
        {ok, Updated@1} ->
            _pipe = lightspeed@cluster@durable_session:request_takeover(
                Updated@1,
                <<"node-a"/utf8>>,
                1,
                lightspeed@cluster@durable_session:expected_token(
                    <<"s-1"/utf8>>,
                    <<"node-a"/utf8>>,
                    1
                ),
                11
            ),
            ownership_result_label(_pipe);

        {error, Error@1} ->
            lightspeed@cluster@durable_session:ownership_error_label(Error@1)
    end,
    Split_label = case Takeover of
        {ok, Updated@2} ->
            _pipe@1 = lightspeed@cluster@durable_session:request_takeover(
                Updated@2,
                <<"node-c"/utf8>>,
                2,
                lightspeed@cluster@durable_session:expected_token(
                    <<"s-1"/utf8>>,
                    <<"node-c"/utf8>>,
                    2
                ),
                12
            ),
            ownership_result_label(_pipe@1);

        {error, Error@2} ->
            lightspeed@cluster@durable_session:ownership_error_label(Error@2)
    end,
    Passed = ((Takeover_label =:= <<"ok"/utf8>>) andalso (Stale_label =:= <<"stale_owner:2:1"/utf8>>))
    andalso (Split_label =:= <<"split_brain:node-b:node-c:2"/utf8>>),
    {Passed,
        <<<<<<<<<<<<<<"takeover="/utf8, Takeover_label/binary>>/binary,
                                "|fence="/utf8>>/binary,
                            Takeover_signature/binary>>/binary,
                        "|stale="/utf8>>/binary,
                    Stale_label/binary>>/binary,
                "|split="/utf8>>/binary,
            Split_label/binary>>}.

-file("src/lightspeed/ops/failover_harness.gleam", 420).
-spec backends_valid(
    list(lightspeed@cluster@durable_session:persistence_backend())
) -> boolean().
backends_valid(Backends) ->
    case Backends of
        [] ->
            true;

        [Backend | Rest] ->
            Contract = lightspeed@cluster@durable_session:start(
                <<"s-check"/utf8>>,
                <<"node-a"/utf8>>,
                <<"/counter"/utf8>>,
                Backend,
                rehydrate,
                0,
                25,
                1
            ),
            lightspeed@cluster@durable_session:valid(Contract) andalso backends_valid(
                Rest
            )
    end.

-file("src/lightspeed/ops/failover_harness.gleam", 186).
-spec evaluate_supported_backends() -> {boolean(), binary()}.
evaluate_supported_backends() ->
    Backends = lightspeed@cluster@durable_session:supported_backends(),
    Labels = gleam@list:map(
        Backends,
        fun lightspeed@cluster@durable_session:backend_label/1
    ),
    Passed = (erlang:length(Backends) =:= 3) andalso backends_valid(Backends),
    {Passed, join_with(<<","/utf8>>, Labels)}.

-file("src/lightspeed/ops/failover_harness.gleam", 176).
-spec evaluate(scenario()) -> {boolean(), binary()}.
evaluate(Scenario) ->
    case Scenario of
        supported_backends ->
            evaluate_supported_backends();

        ownership_fencing ->
            evaluate_ownership_fencing();

        crash_restart_failover ->
            evaluate_crash_restart_failover();

        resume_policy_matrix ->
            evaluate_resume_policy_matrix();

        reconnect_continuity_slo ->
            evaluate_reconnect_continuity_slo()
    end.

-file("src/lightspeed/ops/failover_harness.gleam", 57).
?DOC(" Run one scenario twice and require deterministic parity.\n").
-spec run_scenario(scenario()) -> scenario_outcome().
run_scenario(Scenario) ->
    {First_passed, First_signature} = evaluate(Scenario),
    {Second_passed, Second_signature} = evaluate(Scenario),
    Deterministic = (First_passed =:= Second_passed) andalso (First_signature
    =:= Second_signature),
    Passed = (First_passed andalso Second_passed) andalso Deterministic,
    {scenario_outcome, Scenario, Passed, Deterministic, First_signature}.

-file("src/lightspeed/ops/failover_harness.gleam", 38).
?DOC(" Run all M27 scenarios.\n").
-spec run_matrix() -> report().
run_matrix() ->
    Outcomes = begin
        _pipe = [supported_backends,
            ownership_fencing,
            crash_restart_failover,
            resume_policy_matrix,
            reconnect_continuity_slo],
        gleam@list:map(_pipe, fun run_scenario/1)
    end,
    {report, Outcomes, count_failed(Outcomes), count_nondeterministic(Outcomes)}.

-file("src/lightspeed/ops/failover_harness.gleam", 73).
?DOC(" Scenario label.\n").
-spec scenario_label(scenario()) -> binary().
scenario_label(Scenario) ->
    case Scenario of
        supported_backends ->
            <<"supported_backends"/utf8>>;

        ownership_fencing ->
            <<"ownership_fencing"/utf8>>;

        crash_restart_failover ->
            <<"crash_restart_failover"/utf8>>;

        resume_policy_matrix ->
            <<"resume_policy_matrix"/utf8>>;

        reconnect_continuity_slo ->
            <<"reconnect_continuity_slo"/utf8>>
    end.

-file("src/lightspeed/ops/failover_harness.gleam", 84).
?DOC(" Stable pass/fail label.\n").
-spec pass_fail_label(scenario_outcome()) -> binary().
pass_fail_label(Outcome) ->
    case erlang:element(3, Outcome) of
        true ->
            <<"pass"/utf8>>;

        false ->
            <<"fail"/utf8>>
    end.

-file("src/lightspeed/ops/failover_harness.gleam", 92).
?DOC(" Scenario signature.\n").
-spec signature(scenario_outcome()) -> binary().
signature(Outcome) ->
    erlang:element(5, Outcome).

-file("src/lightspeed/ops/failover_harness.gleam", 97).
?DOC(" Scenario accessor.\n").
-spec scenario(scenario_outcome()) -> scenario().
scenario(Outcome) ->
    erlang:element(2, Outcome).

-file("src/lightspeed/ops/failover_harness.gleam", 102).
?DOC(" Scenario determinism accessor.\n").
-spec deterministic(scenario_outcome()) -> boolean().
deterministic(Outcome) ->
    erlang:element(4, Outcome).

-file("src/lightspeed/ops/failover_harness.gleam", 107).
?DOC(" Report outcomes.\n").
-spec outcomes(report()) -> list(scenario_outcome()).
outcomes(Report) ->
    erlang:element(2, Report).

-file("src/lightspeed/ops/failover_harness.gleam", 112).
?DOC(" Failed scenario count.\n").
-spec failed_scenarios(report()) -> integer().
failed_scenarios(Report) ->
    erlang:element(3, Report).

-file("src/lightspeed/ops/failover_harness.gleam", 117).
?DOC(" Nondeterministic scenario count.\n").
-spec nondeterministic_failures(report()) -> integer().
nondeterministic_failures(Report) ->
    erlang:element(4, Report).

-file("src/lightspeed/ops/failover_harness.gleam", 481).
-spec bool_label(boolean()) -> binary().
bool_label(Value) ->
    case Value of
        true ->
            <<"true"/utf8>>;

        false ->
            <<"false"/utf8>>
    end.

-file("src/lightspeed/ops/failover_harness.gleam", 122).
?DOC(" Stable report signature.\n").
-spec report_signature(report()) -> binary().
report_signature(Report) ->
    Entries = gleam@list:map(
        erlang:element(2, Report),
        fun(Outcome) ->
            <<<<<<<<<<<<(scenario_label(erlang:element(2, Outcome)))/binary,
                                    "="/utf8>>/binary,
                                (pass_fail_label(Outcome))/binary>>/binary,
                            ":deterministic="/utf8>>/binary,
                        (bool_label(erlang:element(4, Outcome)))/binary>>/binary,
                    ":"/utf8>>/binary,
                (erlang:element(5, Outcome))/binary>>
        end
    ),
    join_with(<<";"/utf8>>, Entries).

-file("src/lightspeed/ops/failover_harness.gleam", 138).
?DOC(" Deterministic snapshot signature for fixture drift gates.\n").
-spec snapshot_signature() -> binary().
snapshot_signature() ->
    <<<<<<"m27.snapshot.v"/utf8, (erlang:integer_to_binary(1))/binary>>/binary,
            "|"/utf8>>/binary,
        (report_signature(run_matrix()))/binary>>.

-file("src/lightspeed/ops/failover_harness.gleam", 146).
?DOC(" Deterministic markdown report for fixture scripts.\n").
-spec snapshot_report_markdown() -> binary().
snapshot_report_markdown() ->
    Report = run_matrix(),
    Failed = failed_scenarios(Report),
    Nondeterministic = nondeterministic_failures(Report),
    Status = case (Failed =:= 0) andalso (Nondeterministic =:= 0) of
        true ->
            <<"OK"/utf8>>;

        false ->
            <<"FAIL"/utf8>>
    end,
    <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<"# Failover Fixture Report\n\n"/utf8,
                                                                            "snapshot_version: "/utf8>>/binary,
                                                                        (erlang:integer_to_binary(
                                                                            1
                                                                        ))/binary>>/binary,
                                                                    "\n"/utf8>>/binary,
                                                                "status: "/utf8>>/binary,
                                                            Status/binary>>/binary,
                                                        "\n"/utf8>>/binary,
                                                    "failed_scenarios: "/utf8>>/binary,
                                                (erlang:integer_to_binary(
                                                    Failed
                                                ))/binary>>/binary,
                                            "\n"/utf8>>/binary,
                                        "nondeterministic_failures: "/utf8>>/binary,
                                    (erlang:integer_to_binary(Nondeterministic))/binary>>/binary,
                                "\n\n"/utf8>>/binary,
                            "snapshot_signature: "/utf8>>/binary,
                        (snapshot_signature())/binary>>/binary,
                    "\n\n"/utf8>>/binary,
                "report_signature: "/utf8>>/binary,
            (report_signature(Report))/binary>>/binary,
        "\n"/utf8>>.