import sys
from pathlib import Path
sys.path.insert(0, str(Path(__file__).parent.parent / "python-backend"))

from datetime import date, timedelta
from core.coverage_calculator import ShipmentRecord, calculate_coverage, CoverageFlag

TODAY = date.today()

def make_record(**kwargs):
    defaults = dict(
        patient_id="PT001",
        device_type="dexcom_g7",
        shipment_date=TODAY - timedelta(days=10),
        quantity=1,
        payer="medicare",
        component="sensor",
    )
    defaults.update(kwargs)
    return ShipmentRecord(**defaults)

def test_shipment_record_accepts_csv_visit_date():
    r = make_record(csv_visit_date=TODAY - timedelta(days=30))
    assert r.csv_visit_date == TODAY - timedelta(days=30)

def test_shipment_record_accepts_doc_fields():
    r = make_record(
        csv_swo_status="On File",
        csv_pecos_verified="Yes",
        csv_pa_status="Not Required",
        csv_diagnosis_on_file="Yes",
    )
    assert r.csv_swo_status == "On File"
    assert r.csv_pecos_verified == "Yes"

def test_shipment_record_doc_fields_default_none():
    r = make_record()
    assert r.csv_visit_date is None
    assert r.csv_swo_status is None
    assert r.csv_transfer_from is None


def test_supply_lapsed_flag_when_coverage_ended():
    # Shipment 200 days ago, 1 sensor (10 wear days) — coverage ended long ago
    r = make_record(shipment_date=TODAY - timedelta(days=200), quantity=1)
    result = calculate_coverage(r)
    assert result.flag == CoverageFlag.SUPPLY_LAPSED

def test_renewal_critical_at_45_days():
    # Last confirmed visit was 135 days ago — next visit due in 45 days
    r = make_record(
        shipment_date=TODAY - timedelta(days=10),
        quantity=1,
        csv_visit_date=TODAY - timedelta(days=135),
    )
    result = calculate_coverage(r)
    assert result.flag == CoverageFlag.RENEWAL_CRITICAL

def test_renewal_elevated_at_60_days():
    r = make_record(
        shipment_date=TODAY - timedelta(days=10),
        quantity=1,
        csv_visit_date=TODAY - timedelta(days=120),
    )
    result = calculate_coverage(r)
    assert result.flag == CoverageFlag.RENEWAL_ELEVATED

def test_renewal_soon_at_90_days():
    r = make_record(
        shipment_date=TODAY - timedelta(days=10),
        quantity=1,
        csv_visit_date=TODAY - timedelta(days=90),
    )
    result = calculate_coverage(r)
    assert result.flag == CoverageFlag.RENEWAL_SOON

def test_active_when_visit_far_away():
    # 6 sensors × 10 days = 60-day supply, shipped 10 days ago → 50 days left (outside refill window)
    # visit 10 days ago → 170 days until next due → not in any RENEWAL tier
    r = make_record(
        shipment_date=TODAY - timedelta(days=10),
        quantity=6,
        csv_visit_date=TODAY - timedelta(days=10),
    )
    result = calculate_coverage(r)
    assert result.flag == CoverageFlag.ACTIVE

def test_transfer_pending_flag():
    r = make_record(csv_transfer_from="Prior Supplier LLC")
    result = calculate_coverage(r)
    assert result.flag == CoverageFlag.TRANSFER_PENDING

def test_priority_sort_order():
    lapsed = make_record(shipment_date=TODAY - timedelta(days=200))
    critical = make_record(patient_id="PT002", shipment_date=TODAY - timedelta(days=10),
                           csv_visit_date=TODAY - timedelta(days=135))
    active = make_record(patient_id="PT003", shipment_date=TODAY - timedelta(days=10),
                         quantity=6, csv_visit_date=TODAY - timedelta(days=10))
    from core.coverage_calculator import calculate_batch
    results = calculate_batch([active, critical, lapsed])
    assert results[0].flag == CoverageFlag.SUPPLY_LAPSED
    assert results[1].flag == CoverageFlag.RENEWAL_CRITICAL
    assert results[2].flag == CoverageFlag.ACTIVE