"""Replay a captured /dev/iec0 record stream and check the produced trace.

End-to-end Phase 0 test: build the canonical session, round-trip it through the
binary wire format, and assert the formatted trace matches the documented PoC
output (PLAN.md §8).
"""

from __future__ import annotations

import io

from iecpoc import device
from iecpoc.log import TraceFormatter

from . import fixtures


def _trace(records, my_address=4, raw=False):
    return list(TraceFormatter(my_address=my_address, raw=raw).format_stream(records))


# --- wire-format round trip -------------------------------------------------
def test_record_roundtrip():
    rec = device.IecRecord(device.KIND_DATA, 0x48, device.FLAG_EOI, 123456789)
    assert device.IecRecord.from_bytes(rec.to_bytes()) == rec


def test_iter_records_roundtrip():
    records = fixtures.build_session()
    buf = io.BytesIO()
    device.write_records(buf, records)
    buf.seek(0)
    assert list(device.iter_records(buf)) == records


def test_iter_records_rejects_truncated():
    buf = io.BytesIO(b"\x00\x01\x02")  # < RECORD_SIZE
    import pytest

    with pytest.raises(ValueError):
        list(device.iter_records(buf))


# --- captured binary fixture matches the in-memory builder ------------------
def test_capture_file_matches_builder():
    with open(fixtures.CAPTURE_PATH, "rb") as fh:
        from_file = list(device.iter_records(fh))
    assert from_file == fixtures.build_session()


# --- trace formatting -------------------------------------------------------
def test_trace_contains_plan_section8_lines():
    trace = _trace(fixtures.build_session())

    # the §8 command-phase lines
    assert "[IDLE]   waiting for ATN" in trace
    assert "[ATN]    asserted -> DATA low (ack)" in trace
    assert any(
        line.startswith("[CMD]    $24  LISTEN 4") and line.endswith("(addressed: ME)")
        for line in trace
    )
    assert "[CMD]    $F0  OPEN  SA=0" in trace
    assert "[ATN]    released -> LISTENER" in trace
    assert "[ATN]    asserted -> command phase" in trace
    assert "[CMD]    $3F  UNLISTEN" in trace
    assert "[CMD]    $E0  CLOSE SA=0" in trace
    assert "[ATN]    released -> not addressed -> IDLE" in trace


def test_trace_data_bytes_and_eoi():
    trace = _trace(fixtures.build_session())
    # HELLO WORLD bytes appear as glyphs
    assert "[DATA]   $48 'H'" in trace
    assert "[DATA]   $4F 'O'" in trace
    assert "[DATA]   $20 ' '" in trace
    # each PRINT# record ends with a CR carrying EOI
    assert "[DATA]   $0D <CR>   <EOI>" in trace
    # exactly two EOI markers (two PRINT# statements)
    assert sum("<EOI>" in line for line in trace) == 2


def test_trace_full_text_reconstructable():
    """The data bytes, in order, reconstruct the two printed lines."""
    data_bytes = [r.value for r in fixtures.build_session() if r.is_data]
    text = bytes(data_bytes).decode("ascii")
    assert text == "HELLO WORLD\rLINE TWO\r"


def test_command_not_for_us_has_no_me_annotation():
    # if we are device 8, LISTEN 4 is not for us
    trace = _trace(fixtures.build_session(), my_address=8)
    assert "[CMD]    $24  LISTEN 4" in trace
    assert not any("(addressed: ME)" in line for line in trace)


def test_raw_mode_is_hex_only():
    trace = _trace(fixtures.build_session(), raw=True)
    # no bracketed tags in raw mode
    assert all(not line.startswith("[") for line in trace)
    # first emitted byte is the LISTEN 4 command byte $24
    assert trace[0] == "24"
    # data bytes present as hex
    assert "48" in trace  # 'H'