"""999-ack dump from Gainwell for Mar–Jun 2026.

Reconciles pulled 999 acks against the in-window 4,509 NOT_IN_835 visits.
Visits that are 999-rejected go in one bucket; visits that simply
never made it to submission go in another.

These tests exercise the pure-function surface of
``cyclone.rebill.pull_999_acks`` (no SFTP, no DB). The
``pull_and_classify`` orchestrator wraps the existing
``Scheduler.process_inbound_files`` machinery and is integration-
covered by the existing ``test_api_pull_inbound.py`` / CLI smoke
tests — adding a new test here would just duplicate that coverage
and require a live SFTP server.
"""
from __future__ import annotations

from datetime import date

from cyclone.rebill.pull_999_acks import (
    Bucket,
    PullResult,
    classify_not_in_835_visits,
)


# ---------------------------------------------------------------------------
# Core: split by 999-rejection presence
# ---------------------------------------------------------------------------


def test_classify_splits_by_999_rejection_presence() -> None:
    visits = [
        ("J813715", date(2026, 6, 27), "T1019"),
        ("OTHER",   date(2026, 6, 27), "T1019"),
    ]
    nine99_rejected = {("J813715", date(2026, 6, 27), "T1019")}
    out = classify_not_in_835_visits(visits, nine99_rejected)
    assert out["J813715"].value == Bucket.REJECTED_AT_999.value
    assert out["OTHER"].value   == Bucket.NEVER_SUBMITTED.value


# ---------------------------------------------------------------------------
# Edge cases
# ---------------------------------------------------------------------------


def test_classify_empty_input_returns_empty_dict() -> None:
    """No visits → empty bucket map (no-op)."""
    out = classify_not_in_835_visits([], set())
    assert out == {}
    # Also: empty visits + non-empty rejection set stays empty.
    out2 = classify_not_in_835_visits(
        [], {("J813715", date(2026, 6, 27), "T1019")},
    )
    assert out2 == {}


def test_classify_all_rejected() -> None:
    """Every visit is in the 999-rejection set → every bucket is REJECTED_AT_999."""
    v1 = ("MEM001", date(2026, 3, 15), "T1019")
    v2 = ("MEM002", date(2026, 4, 1),  "T1019")
    out = classify_not_in_835_visits([v1, v2], {v1, v2})
    assert out == {
        "MEM001": Bucket.REJECTED_AT_999,
        "MEM002": Bucket.REJECTED_AT_999,
    }


def test_classify_all_never_submitted() -> None:
    """Visits present, rejection set empty → every bucket is NEVER_SUBMITTED."""
    visits = [
        ("G1", date(2026, 3, 1), "T1019"),
        ("G2", date(2026, 3, 2), "T1019"),
        ("G3", date(2026, 3, 3), "T1019"),
    ]
    out = classify_not_in_835_visits(visits, set())
    assert out == {m: Bucket.NEVER_SUBMITTED for m in ("G1", "G2", "G3")}


def test_classify_keyed_by_member_id() -> None:
    """Output is a dict keyed by member_id, not by the visit tuple.

    The spec's contract is "keyed on member_id" — Pipeline B groups
    by member for the ISO-week rebill, so the classification map
    collapses to one entry per member. The visit tuple's procedure
    and dos parts are the *match key* against the 999 rejection set,
    not the *output key*.

    When two visits for the same member resolve to different
    buckets (one rejected, one not), the dict-construction order
    means the *last* visit wins. This test pins that semantic —
    Pipeline B re-resolves per-visit at the next layer so the
    member-level bucket is just a coarse pre-filter.
    """
    visits = [
        ("SHARED", date(2026, 5, 1), "T1019"),
        ("SHARED", date(2026, 5, 8), "T1019"),
    ]
    # First visit IS in the rejected set, second is not.
    nine99_rejected = {("SHARED", date(2026, 5, 1), "T1019")}
    out = classify_not_in_835_visits(visits, nine99_rejected)
    # Last-write-wins: the second visit is NEVER_SUBMITTED, so the
    # member-level bucket ends up as NEVER_SUBMITTED. This is the
    # documented coarse-filter semantic — Pipeline B does per-visit
    # re-resolution downstream.
    assert out == {"SHARED": Bucket.NEVER_SUBMITTED}

    # Reverse the rejection set: only the second visit is rejected.
    # Last visit wins → REJECTED_AT_999.
    nine99_rejected = {("SHARED", date(2026, 5, 8), "T1019")}
    out = classify_not_in_835_visits(visits, nine99_rejected)
    assert out == {"SHARED": Bucket.REJECTED_AT_999}


def test_classify_distinct_members_dont_collide() -> None:
    """Two distinct members, only one rejected → independent bucket entries."""
    visits = [
        ("ALICE", date(2026, 6, 1), "T1019"),
        ("BOB",   date(2026, 6, 1), "T1019"),
    ]
    nine99_rejected = {("ALICE", date(2026, 6, 1), "T1019")}
    out = classify_not_in_835_visits(visits, nine99_rejected)
    assert out == {
        "ALICE": Bucket.REJECTED_AT_999,
        "BOB":   Bucket.NEVER_SUBMITTED,
    }


# ---------------------------------------------------------------------------
# PullResult shape — guards against accidental field drift
# ---------------------------------------------------------------------------


def test_pull_result_is_frozen_dataclass() -> None:
    """``PullResult`` must be frozen so callers can't mutate the summary."""
    pr = PullResult(
        total_pulled=10,
        rejected_at_999=3,
        not_in_835=4,
        rejected_breakdown={"R": 2, "E": 1},
    )
    assert pr.total_pulled == 10
    assert pr.rejected_at_999 == 3
    assert pr.not_in_835 == 4
    assert pr.rejected_breakdown == {"R": 2, "E": 1}
    # Frozen: assignment must raise.
    import dataclasses
    try:
        pr.total_pulled = 99  # type: ignore[misc]
    except dataclasses.FrozenInstanceError:
        pass
    else:
        raise AssertionError("PullResult must be frozen")


def test_bucket_values_are_json_friendly_strings() -> None:
    """Bucket values serialize cleanly to JSON (string-enum contract)."""
    import json
    payload = {
        "j1": Bucket.REJECTED_AT_999.value,
        "j2": Bucket.NEVER_SUBMITTED.value,
    }
    # Round-trip — no enum leakage into the JSON output.
    assert json.loads(json.dumps(payload)) == {
        "j1": "REJECTED_AT_999",
        "j2": "NEVER_SUBMITTED",
    }