from __future__ import annotations

import json
from pathlib import Path

import pytest

from k1link.device_plugins.xgrids_k1.mqtt.capture import FRAME_HEADER, RAW_MAGIC
from k1link.device_plugins.xgrids_k1.viewer.replay import (
    ReplayFormatError,
    detect_replay_format,
    iter_replay_messages,
)


def _write_native(path: Path, topic: str, payload: bytes) -> None:
    topic_raw = topic.encode()
    path.write_bytes(
        RAW_MAGIC + FRAME_HEADER.pack(len(topic_raw), len(payload)) + topic_raw + payload
    )


def _append_native(path: Path, topic: str, payload: bytes) -> None:
    topic_raw = topic.encode()
    with path.open("ab") as stream:
        stream.write(FRAME_HEADER.pack(len(topic_raw), len(payload)))
        stream.write(topic_raw)
        stream.write(payload)


def test_native_replay_uses_aligned_metadata_timing(tmp_path: Path) -> None:
    capture = tmp_path / "mqtt.raw.k1mqtt"
    _write_native(capture, "lixel/application/report/lio_pose", b"pose")
    (tmp_path / "mqtt.metadata.jsonl").write_text(
        json.dumps(
            {
                "record_type": "message",
                "sequence": 1,
                "received_at_epoch_ns": 123_000_000_000,
                "received_monotonic_ns": 456,
            }
        )
        + "\n"
    )

    assert detect_replay_format(capture) == "k1mqtt"
    message = list(iter_replay_messages(capture))[0]
    assert message.topic.endswith("lio_pose")
    assert message.payload == b"pose"
    assert message.received_at_epoch_ns == 123_000_000_000
    assert message.received_monotonic_ns == 456


def test_native_replay_stops_at_crash_truncated_metadata_tail(tmp_path: Path) -> None:
    capture = tmp_path / "mqtt.raw.k1mqtt"
    _write_native(capture, "RealtimePointcloud", b"first")
    _append_native(capture, "RealtimePointcloud", b"uncommitted-tail")
    first_record = {
        "record_type": "message",
        "sequence": 1,
        "received_at_epoch_ns": 123_000_000_000,
        "received_monotonic_ns": 456,
    }
    (tmp_path / "mqtt.metadata.jsonl").write_text(
        json.dumps(first_record) + "\n" + '{"record_type":"message"',
        encoding="utf-8",
    )

    messages = list(iter_replay_messages(capture))

    assert [message.payload for message in messages] == [b"first"]


def test_native_replay_rejects_newline_terminated_metadata_corruption(tmp_path: Path) -> None:
    capture = tmp_path / "mqtt.raw.k1mqtt"
    _write_native(capture, "RealtimePointcloud", b"frame")
    (tmp_path / "mqtt.metadata.jsonl").write_text("{corrupt\n", encoding="utf-8")

    with pytest.raises(ReplayFormatError, match="not valid JSON"):
        list(iter_replay_messages(capture))


def test_legacy_tsv_replay_validates_and_decodes_payload(tmp_path: Path) -> None:
    capture = tmp_path / "payloads.tsv"
    capture.write_bytes(b"1784124315.186225000\tRealtimePath\t4\t0001aaff\n")

    assert detect_replay_format(capture) == "legacy_tsv"
    message = list(iter_replay_messages(capture))[0]
    assert message.received_at_epoch_ns == 1_784_124_315_186_225_000
    assert message.payload == b"\x00\x01\xaa\xff"


@pytest.mark.parametrize(
    "line",
    [
        b"1\tonly\tthree\n",
        b"bad\ttopic\t1\t00\n",
        b"1\ttopic\t2\t00\n",
        b"1\ttopic\t1\tzz\n",
    ],
)
def test_legacy_tsv_rejects_unreviewed_shapes(tmp_path: Path, line: bytes) -> None:
    capture = tmp_path / "payloads.tsv"
    capture.write_bytes(line)
    with pytest.raises(ReplayFormatError):
        list(iter_replay_messages(capture))