"""Tests for ORM model definitions and CRUD."""

from __future__ import annotations

import enum
from datetime import date, datetime, timezone
from decimal import Decimal

import pytest

from cyclone import db
from cyclone.db import ActivityEvent, Base, Batch, CasAdjustment, Claim, ClaimState, Match, Remittance


@pytest.fixture(autouse=True)
def _setup(tmp_path, monkeypatch):
    monkeypatch.setenv("CYCLONE_DB_URL", f"sqlite:///{tmp_path}/test.db")
    db._reset_for_tests()
    db.init_db()


def test_claim_state_enum_values():
    assert ClaimState.SUBMITTED.value == "submitted"
    assert ClaimState.RECEIVED.value == "received"
    assert ClaimState.PAID.value == "paid"
    assert ClaimState.PARTIAL.value == "partial"
    assert ClaimState.DENIED.value == "denied"
    assert ClaimState.RECONCILED.value == "reconciled"
    assert ClaimState.REVERSED.value == "reversed"
    # 8 values total (REJECTED was added for 999 AK9 set-level R/E).
    assert len(list(ClaimState)) == 8


def test_create_and_query_batch():
    with db.SessionLocal()() as s:
        b = Batch(
            id="b1",
            kind="837p",
            input_filename="test.txt",
            parsed_at=datetime(2026, 6, 19, 12, 0, tzinfo=timezone.utc),
            totals_json={"total_claims": 1},
            validation_json={"passed": True, "warnings": [], "errors": []},
            raw_result_json={"_": "stub"},
        )
        s.add(b)
        s.commit()

    with db.SessionLocal()() as s:
        loaded = s.get(Batch, "b1")
        assert loaded is not None
        assert loaded.kind == "837p"
        assert loaded.totals_json == {"total_claims": 1}


def test_create_and_query_claim_with_default_state():
    with db.SessionLocal()() as s:
        s.add(Batch(
            id="b1", kind="837p", input_filename="x",
            parsed_at=datetime(2026, 6, 19, tzinfo=timezone.utc),
        ))
        c = Claim(
            id="CLM-1",
            batch_id="b1",
            patient_control_number="CLM-1",
            service_date_from=date(2026, 6, 1),
            service_date_to=date(2026, 6, 1),
            charge_amount=Decimal("124.00"),
            provider_npi="1234567890",
            payer_id="SKCO0",
            state=ClaimState.SUBMITTED,
        )
        s.add(c)
        s.commit()

    with db.SessionLocal()() as s:
        loaded = s.get(Claim, "CLM-1")
        assert loaded is not None
        assert loaded.state == ClaimState.SUBMITTED
        assert loaded.charge_amount == Decimal("124.00")
        assert loaded.service_date_from == date(2026, 6, 1)


def test_claim_uses_db_default_when_state_omitted():
    """The `state` column has a DB-side DEFAULT of 'submitted' (per migration
    and ORM `default=`). When the caller omits `state=`, the loaded value
    must be ClaimState.SUBMITTED, not None."""
    with db.SessionLocal()() as s:
        s.add(Batch(
            id="b1", kind="837p", input_filename="x",
            parsed_at=datetime(2026, 6, 19, tzinfo=timezone.utc),
        ))
        c = Claim(
            id="CLM-1",
            batch_id="b1",
            patient_control_number="CLM-1",
            charge_amount=Decimal("0"),
        )
        s.add(c)
        s.commit()

    with db.SessionLocal()() as s:
        loaded = s.get(Claim, "CLM-1")
        assert loaded is not None
        assert loaded.state == ClaimState.SUBMITTED


def test_state_before_reversal_round_trips():
    """`state_before_reversal` is nullable but stores a ClaimState enum.
    Setting it to PAID must round-trip as ClaimState.PAID after commit+reload."""
    with db.SessionLocal()() as s:
        s.add(Batch(
            id="b1", kind="837p", input_filename="x",
            parsed_at=datetime(2026, 6, 19, tzinfo=timezone.utc),
        ))
        c = Claim(
            id="CLM-1",
            batch_id="b1",
            patient_control_number="CLM-1",
            charge_amount=Decimal("50.00"),
            state_before_reversal=ClaimState.PAID,
        )
        s.add(c)
        s.commit()

    with db.SessionLocal()() as s:
        loaded = s.get(Claim, "CLM-1")
        assert loaded is not None
        assert loaded.state_before_reversal == ClaimState.PAID


def test_batch_cascade_delete_drops_claims():
    """Deleting a Batch must cascade-delete its claims (FK is ON DELETE CASCADE
    in migration; ORM relationship uses cascade='all, delete-orphan' which makes
    SQLAlchemy emit the child DELETE at flush time even without
    PRAGMA foreign_keys=ON)."""
    with db.SessionLocal()() as s:
        s.add(Batch(
            id="b1", kind="837p", input_filename="x",
            parsed_at=datetime(2026, 6, 19, tzinfo=timezone.utc),
        ))
        s.add(Claim(
            id="CLM-1",
            batch_id="b1",
            patient_control_number="CLM-1",
            charge_amount=Decimal("0"),
        ))
        s.commit()

    with db.SessionLocal()() as s:
        batch = s.get(Batch, "b1")
        assert batch is not None
        s.delete(batch)
        s.commit()

    with db.SessionLocal()() as s:
        assert s.get(Batch, "b1") is None
        assert s.get(Claim, "CLM-1") is None


def test_create_and_query_remittance():
    with db.SessionLocal()() as s:
        s.add(Batch(
            id="b1", kind="835", input_filename="x",
            parsed_at=datetime(2026, 6, 19, tzinfo=timezone.utc),
        ))
        r = Remittance(
            id="CLP-1",
            batch_id="b1",
            payer_claim_control_number="CLP-1",
            status_code="1",
            total_charge=Decimal("124.00"),
            total_paid=Decimal("124.00"),
            received_at=datetime(2026, 6, 19, tzinfo=timezone.utc),
            service_date=date(2026, 6, 1),
            is_reversal=False,
        )
        s.add(r)
        s.commit()

    with db.SessionLocal()() as s:
        loaded = s.get(Remittance, "CLP-1")
        assert loaded is not None
        assert loaded.status_code == "1"
        assert loaded.total_paid == Decimal("124.00")
        assert loaded.is_reversal is False
        assert loaded.adjustment_amount == Decimal("0")  # default


def test_cas_adjustment_aggregation():
    """Sum of CAS rows for a Remittance equals expected total."""
    with db.SessionLocal()() as s:
        s.add(Batch(
            id="b1", kind="835", input_filename="x",
            parsed_at=datetime(2026, 6, 19, tzinfo=timezone.utc),
        ))
        r = Remittance(
            id="CLP-1", batch_id="b1",
            payer_claim_control_number="CLP-1", status_code="1",
            total_charge=Decimal("124.00"), total_paid=Decimal("62.00"),
            received_at=datetime(2026, 6, 19, tzinfo=timezone.utc),
        )
        s.add(r)
        s.flush()
        s.add_all([
            CasAdjustment(remittance_id="CLP-1", group_code="CO", reason_code="45",
                          amount=Decimal("30.00")),
            CasAdjustment(remittance_id="CLP-1", group_code="PR", reason_code="1",
                          amount=Decimal("32.00")),
        ])
        s.commit()

    from sqlalchemy import select, func
    with db.SessionLocal()() as s:
        total = s.execute(
            select(func.sum(CasAdjustment.amount))
            .where(CasAdjustment.remittance_id == "CLP-1")
        ).scalar_one()
        assert total == Decimal("62.00")


def test_remittance_raw_json_round_trips_dict():
    """JSONText on Remittance.raw_json round-trips a dict, not a string."""
    with db.SessionLocal()() as s:
        s.add(Batch(
            id="b1", kind="835", input_filename="x",
            parsed_at=datetime(2026, 6, 19, tzinfo=timezone.utc),
        ))
        r = Remittance(
            id="CLP-1", batch_id="b1", payer_claim_control_number="CLP-1",
            status_code="1",
            received_at=datetime(2026, 6, 19, tzinfo=timezone.utc),
            raw_json={"x12_segments": ["CLP", "NM1", "SVC"], "version": "005010X221A1"},
        )
        s.add(r)
        s.commit()

    with db.SessionLocal()() as s:
        loaded = s.get(Remittance, "CLP-1")
        assert loaded.raw_json == {"x12_segments": ["CLP", "NM1", "SVC"], "version": "005010X221A1"}


def test_remittance_allows_duplicate_pcn_in_same_batch():
    """An 835 ERA can carry multiple CLP segments with the same
    payer_claim_control_number (e.g. reversals re-referencing the
    original PCN). Remittance identity is by ``id`` (CLP01), not by
    (batch_id, PCN). This test documents the absence of the constraint
    removed in migration 0003.
    """
    with db.SessionLocal()() as s:
        s.add(Batch(
            id="b1", kind="835", input_filename="x",
            parsed_at=datetime(2026, 6, 19, tzinfo=timezone.utc),
        ))
        s.add(Remittance(
            id="CLP-1", batch_id="b1", payer_claim_control_number="SAME",
            status_code="1",
            received_at=datetime(2026, 6, 19, tzinfo=timezone.utc),
        ))
        s.commit()

    with db.SessionLocal()() as s:
        s.add(Remittance(
            id="CLP-2", batch_id="b1", payer_claim_control_number="SAME",
            status_code="2",
            received_at=datetime(2026, 6, 19, tzinfo=timezone.utc),
        ))
        s.commit()  # no IntegrityError — duplicates are allowed

    with db.SessionLocal()() as s:
        rows = s.query(Remittance).filter(Remittance.batch_id == "b1").all()
        assert {r.id for r in rows} == {"CLP-1", "CLP-2"}
        assert {r.payer_claim_control_number for r in rows} == {"SAME"}


def test_remittance_cascade_delete_drops_cas_adjustments():
    """Deleting a Remittance drops its CAS rows via ORM cascade."""
    with db.SessionLocal()() as s:
        s.add(Batch(
            id="b1", kind="835", input_filename="x",
            parsed_at=datetime(2026, 6, 19, tzinfo=timezone.utc),
        ))
        r = Remittance(
            id="CLP-1", batch_id="b1", payer_claim_control_number="CLP-1",
            status_code="1", total_paid=Decimal("62.00"),
            received_at=datetime(2026, 6, 19, tzinfo=timezone.utc),
        )
        s.add(r)
        s.flush()
        s.add(CasAdjustment(remittance_id="CLP-1", group_code="CO",
                             reason_code="45", amount=Decimal("30.00")))
        s.commit()

    with db.SessionLocal()() as s:
        r = s.get(Remittance, "CLP-1")
        s.delete(r)
        s.commit()

    with db.SessionLocal()() as s:
        from sqlalchemy import select
        cas = s.execute(
            select(CasAdjustment).where(CasAdjustment.remittance_id == "CLP-1")
        ).all()
        assert len(cas) == 0


def test_create_match_and_activity_event():
    with db.SessionLocal()() as s:
        s.add(Batch(
            id="b1", kind="835", input_filename="x",
            parsed_at=datetime(2026, 6, 19, tzinfo=timezone.utc),
        ))
        s.add(Claim(
            id="CLM-1", batch_id="b1", patient_control_number="CLM-1",
            charge_amount=Decimal("124.00"), state=ClaimState.SUBMITTED,
        ))
        s.add(Remittance(
            id="CLP-1", batch_id="b1", payer_claim_control_number="CLM-1",
            status_code="1", total_charge=Decimal("124.00"), total_paid=Decimal("124.00"),
            received_at=datetime(2026, 6, 19, tzinfo=timezone.utc),
        ))
        m = Match(
            claim_id="CLM-1", remittance_id="CLP-1",
            strategy="auto", is_reversal=False,
            matched_at=datetime(2026, 6, 19, 13, 0, tzinfo=timezone.utc),
        )
        s.add(m)
        s.flush()
        s.add(ActivityEvent(
            ts=datetime(2026, 6, 19, 13, 0, tzinfo=timezone.utc),
            kind="reconcile", batch_id="b1", claim_id="CLM-1",
            payload_json={"matched": 1},
        ))
        s.commit()

    with db.SessionLocal()() as s:
        loaded = s.get(Match, 1)  # autoincrement id
        assert loaded is not None
        assert loaded.strategy == "auto"
        assert loaded.is_reversal is False

        events = s.query(ActivityEvent).all()
        assert len(events) == 1
        assert events[0].kind == "reconcile"
        assert events[0].payload_json == {"matched": 1}


def test_match_multiple_rows_per_claim():
    """Spec-bug fix (T10): a Claim can have multiple Match rows
    (original payment + reversal = audit trail). UNIQUE on claim_id
    was removed; the constraint test that previously lived here
    asserted the old, incorrect design.
    """
    with db.SessionLocal()() as s:
        s.add(Batch(
            id="b1", kind="835", input_filename="x",
            parsed_at=datetime(2026, 6, 19, tzinfo=timezone.utc),
        ))
        s.add(Claim(id="CLM-1", batch_id="b1", patient_control_number="CLM-1",
                    charge_amount=Decimal("0"), state=ClaimState.SUBMITTED))
        s.add(Remittance(id="CLP-1", batch_id="b1", payer_claim_control_number="x",
                         status_code="1", received_at=datetime.now(timezone.utc)))
        s.add(Remittance(id="CLP-2", batch_id="b1", payer_claim_control_number="y",
                         status_code="1", received_at=datetime.now(timezone.utc)))
        s.add(Match(claim_id="CLM-1", remittance_id="CLP-1", strategy="auto",
                    matched_at=datetime.now(timezone.utc)))
        s.add(Match(claim_id="CLM-1", remittance_id="CLP-2", strategy="manual",
                    matched_at=datetime.now(timezone.utc),
                    is_reversal=True, prior_claim_state=ClaimState.PAID))
        # No IntegrityError — two Match rows per claim are now allowed.
        s.commit()

        rows = s.query(Match).filter(Match.claim_id == "CLM-1").all()
        assert len(rows) == 2
        assert {r.remittance_id for r in rows} == {"CLP-1", "CLP-2"}