"""NFT-PERF-02 — frame-by-frame streaming, no batching (AZ-429 / AC-4.4).

Replays the 5-minute Derkachi flight at the 3 Hz target cadence; reads
SITL-side receipt timestamps for accepted GPS_INPUT (ArduPilot
mavproxy tlog) / MSP2_SENSOR_GPS (iNav SITL MSP capture) messages;
asserts:

* AC-1: ``p95(inter_emit_interval) ≤ 350 ms`` (inter-frame × 1.05).
* AC-2: no window contains ≥3 consecutive missed emits.

Tier-1 OR Tier-2; both parametrizations run. The pure-logic AC-1/AC-2
evaluators are covered by
``e2e/_unit_tests/helpers/test_streaming_evaluator.py``.
"""

from __future__ import annotations

from pathlib import Path

import pytest

from runner.helpers import streaming_evaluator as ste

DERKACHI_DIR = (
    Path(__file__).resolve().parents[3]
    / "_docs"
    / "00_problem"
    / "input_data"
    / "flight_derkachi"
)
DERKACHI_MP4 = DERKACHI_DIR / "flight_derkachi.mp4"

# 5 min Derkachi replay at 3 Hz target. The window length feeds into the
# iNav MSP collector; the ArduPilot path reads the tlog regardless of
# `window_s` (the tlog encodes its own duration).
REPLAY_WINDOW_S = 300.0
INAV_MSP_PORT = 5760
ARDUPILOT_GPS_MSG_KIND = "GPS_INPUT"


@pytest.mark.scenario_id("nft-perf-02")
@pytest.mark.traces_to("AC-4.4,AC-1,AC-2,AC-3")
def test_nft_perf_02_streaming_inter_emit(
    fc_adapter: str,
    vio_strategy: str,
    evidence_dir,  # type: ignore[no-untyped-def]
    run_id: str,
    nfr_recorder,  # type: ignore[no-untyped-def]
    sitl_replay_ready: bool,
) -> None:
    """NFT-PERF-02 AC-1 + AC-2 across `(fc_adapter, vio_strategy)`."""
    if not sitl_replay_ready:
        pytest.skip(
            "NFT-PERF-02 requires `E2E_SITL_REPLAY_DIR` to point at a prepared "
            "SITL replay fixture (AZ-595) carrying the 5 min Derkachi @ 3 Hz "
            "replay. AC-1/AC-2 pure-logic covered by "
            "e2e/_unit_tests/helpers/test_streaming_evaluator.py."
        )

    from runner.helpers import mavproxy_tlog_reader, msp_frame_observer, sitl_observer
    from runner.helpers.frame_source_replay import FrameSourceReplayer
    from runner.helpers.replay_mode import NullFrameSink

    # 1. Drive the 5 min replay (3 Hz target inside the fixture).
    FrameSourceReplayer(NullFrameSink()).replay_video(DERKACHI_MP4)

    # 2. Read SITL-side receipt timestamps for the FC-specific accepted GPS frame.
    host = f"{fc_adapter}-sitl"
    emit_times_ms = _read_emit_times_ms(
        fc_adapter,
        host,
        sitl_observer=sitl_observer,
        mavproxy_tlog_reader=mavproxy_tlog_reader,
    )
    if not emit_times_ms:
        pytest.fail(
            f"NFT-PERF-02: SITL ({host}) reported zero accepted GPS frames "
            "during the 5 min Derkachi replay. The replay fixture exists but "
            "the SUT emitted nothing — fail-loud rather than skip."
        )

    # 3. Evaluate AC-1 + AC-2.
    report = ste.evaluate(emit_times_ms)

    # 4. Emit per-interval + summary CSV evidence.
    base = Path(evidence_dir) / "nft-perf-02" / f"{fc_adapter}-{vio_strategy}"
    ste.write_csv_evidence(base.with_suffix(".csv"), report)
    ste.write_intervals_csv(
        base.with_name(base.name + "-intervals").with_suffix(".csv"),
        emit_times_ms,
    )

    # 5. NFR metrics.
    if report.inter_emit.p50_ms is not None:
        nfr_recorder.record_metric(
            "nft_perf_02.inter_emit_ms_p50", report.inter_emit.p50_ms
        )
    if report.inter_emit.p95_ms is not None:
        nfr_recorder.record_metric(
            "nft_perf_02.inter_emit_ms_p95",
            report.inter_emit.p95_ms,
            ac_id="AC-1",
        )
    if report.inter_emit.max_ms is not None:
        nfr_recorder.record_metric(
            "nft_perf_02.inter_emit_ms_max", report.inter_emit.max_ms
        )
    nfr_recorder.record_metric(
        "nft_perf_02.longest_missed_run",
        float(report.missed_emits.longest_run),
        ac_id="AC-2",
    )

    # 6. AC assertions.
    assert report.inter_emit.passes_p95, (
        f"AC-1: p95(inter_emit) > {ste.STREAMING_P95_BUDGET_MS} ms "
        f"(got {report.inter_emit.p95_ms} ms over "
        f"{report.inter_emit.interval_count} intervals; "
        f"max={report.inter_emit.max_ms} ms)"
    )
    assert report.missed_emits.passes, (
        f"AC-2: longest missed-emit run = {report.missed_emits.longest_run} "
        f">= limit {report.missed_emits.limit}; "
        f"first window @ "
        f"{report.missed_emits.windows[0].start_ms if report.missed_emits.windows else 'n/a'} ms"
    )


def _read_emit_times_ms(
    fc_adapter: str,
    host: str,
    *,
    sitl_observer,  # type: ignore[no-untyped-def]
    mavproxy_tlog_reader,  # type: ignore[no-untyped-def]
) -> list[float]:
    """Project SITL-side accepted-GPS receipt timestamps into a ms list.

    * ArduPilot: filter mavproxy tlog for ``GPS_INPUT`` and project
      ``timestamp_us / 1000``.
    * iNav: ``collect_inav_msp_frames`` then filter for
      ``MSP2_SENSOR_GPS`` (function id ``0x1F03``) and project
      ``monotonic_ms`` directly.
    """
    if fc_adapter == "ardupilot":
        tlog_path = sitl_observer.capture_ap_tlog(host=host, duration_s=REPLAY_WINDOW_S)
        return [
            float(msg.timestamp_us) / 1000.0
            for msg in mavproxy_tlog_reader.iter_messages(tlog_path)
            if msg.msg_type == ARDUPILOT_GPS_MSG_KIND
        ]
    if fc_adapter == "inav":
        capture = sitl_observer.collect_inav_msp_frames(
            host=host, port=INAV_MSP_PORT, window_s=REPLAY_WINDOW_S
        )
        return [
            float(f.monotonic_ms)
            for f in capture.frames
            if f.function_id == msp_frame_observer.MSP2_SENSOR_GPS_FUNCTION_ID
        ]
    raise ValueError(f"unknown fc_adapter {fc_adapter!r}")