"""SS3 RQ1 loader — pcap→pairs plumbing, on SYNTHETIC pcaps only.

These pin that the loader reconstructs the RQ1 (entry,exit) pair set from real
per-hop pcap bytes and classifies runs by their persisted metrics.json — WITHOUT
touching any confirmatory data (prereg §2 blinding). Detector accuracy itself is
covered by test_sor_analysis/test_sor_confirm; here we only prove the wiring.
"""

import json
import struct

from cmd_chat.sor.analysis import confirm_load


def _write_series_pcap(path, series):
    """Minimal LINKTYPE_RAW pcap placing one packet of size series[k] at t=k, so
    bin_pcap_bytes(path, bins=len(series)) reproduces `series` bin-for-bin."""
    path.parent.mkdir(parents=True, exist_ok=True)
    with open(path, "wb") as f:
        f.write(struct.pack("<IHHiIII", 0xA1B2C3D4, 2, 4, 0, 0, 65535, 101))
        for k, nbytes in enumerate(series):
            f.write(struct.pack("<IIII", k, 0, nbytes, nbytes))
            f.write(b"x" * nbytes)


def _write_circuit(run_dir, cid, ingress_series, egress_series):
    pdir = run_dir / "circuits" / cid / "pcap"
    _write_series_pcap(pdir / "hop0.pcap", ingress_series)      # ingress
    _write_series_pcap(pdir / "hop2.pcap", egress_series)       # egress (hops=3)


def _write_metrics(run_dir, cell_id, rq, padding):
    run_dir.mkdir(parents=True, exist_ok=True)
    (run_dir / "metrics.json").write_text(
        json.dumps({"cell_id": cell_id, "rq": rq, "padding_applied": padding}),
        encoding="utf-8",
    )


def test_classify_run_reads_persisted_metrics(tmp_path):
    rd = tmp_path / "cell-x-r0"
    _write_metrics(rd, "RQ1/topo=1house/selector=static/bridge=on", "RQ1", False)
    info = confirm_load.classify_run(rd)
    assert info["cell_id"].endswith("bridge=on")
    assert info["rq"] == "RQ1" and info["padding_applied"] is False


def test_reconstruct_run_pairs_shape_and_linkage(tmp_path):
    rd = tmp_path / "cell-on-r0"
    _write_metrics(rd, "RQ1/topo=1house/selector=static/bridge=on", "RQ1", False)
    # Two circuits with anti-correlated temporal profiles; each hop0/hop2 share
    # their own circuit's profile → linked (diagonal) pearson high, cross low.
    _write_circuit(rd, "c0", [100, 10, 100, 10], [100, 10, 100, 10])
    _write_circuit(rd, "c1", [10, 100, 10, 100], [10, 100, 10, 100])
    pairs = confirm_load.reconstruct_run_pairs(rd, bins=4, hops=3)
    assert len(pairs) == 4                                   # 2x2 score matrix
    linked = [s for s, is_linked in pairs if is_linked]
    unlinked = [s for s, is_linked in pairs if not is_linked]
    assert len(linked) == 2 and len(unlinked) == 2
    # Real measured signal carried through: same-circuit correlation beats cross.
    assert min(linked) > max(unlinked)


def test_collect_rq1_p1_selects_only_bridge_on_nopad(tmp_path):
    # bridge=on (leak arm) — should be collected.
    on = tmp_path / "cell-on-r0"
    _write_metrics(on, "RQ1/topo=1house/selector=static/bridge=on", "RQ1", False)
    _write_circuit(on, "c0", [100, 10, 100, 10], [100, 10, 100, 10])
    # bridge=on+padding — excluded (padding arm).
    pad = tmp_path / "cell-pad-r0"
    _write_metrics(pad, "RQ1/topo=1house/selector=static/bridge=on+padding", "RQ1", True)
    _write_circuit(pad, "c0", [50, 50, 50, 50], [50, 50, 50, 50])
    # RQ2 cell — excluded (wrong RQ).
    rq2 = tmp_path / "cell-rq2-r0"
    _write_metrics(rq2, "RQ2/topo=directory-federated/selector=static/bridge=off", "RQ2", False)
    _write_circuit(rq2, "c0", [1, 2, 3, 4], [1, 2, 3, 4])

    pairs = confirm_load.collect_rq1_p1_pairs(tmp_path, bins=4, hops=3)
    assert len(pairs) == 1                                   # only the 1-circuit bridge=on run
    assert pairs[0][1] is True                               # its single diagonal pair