src/Matching Functions/edge_case_tests.py

"""
Ad-hoc edge case tests — scenarios NOT in run_pipeline_tests.py
Run: python edge_case_tests.py
"""
import sys, os
sys.path.insert(0, os.path.dirname(os.path.abspath(__file__)))

from datetime import date
from decimal import Decimal
from types import SimpleNamespace
from invoice_pipeline import run_invoice_pipeline
from two_way_match import InvoiceHeader, InvoiceLine, POHeader, POLine
from three_way_match import GRLineItem
from contract_match import ContractInvoiceHeader, ContractRecord, RateCardItem

# ── Shared master data ────────────────────────────────────────────────────────
VENDORS = [SimpleNamespace(
    id=100, tenant_id=1, legal_name="Acme Corporation Ltd",
    vendor_name="Acme Corporation Ltd", vendor_status="active",
    deleted_at=None, billing_country="GB", billing_state=None,
    tax_registration_number="GB123456715", payment_terms=30,
    exemption_status="standard",
)]
VENDOR_TAX_IDS = [SimpleNamespace(
    tenant_id=1, vendor_id=100, tax_id_canonical="123456715",
    tax_id_type="VAT-GB", verified_at="2024-01-01",
    deleted_at=None, effective_from=None, effective_to=None,
)]
VENDOR_BANK_ACCOUNTS = [SimpleNamespace(
    tenant_id=1, vendor_id=100, iban_canonical="GB29NWBK60161331926819",
    acc_no_canonical="31926819", swift_bic="NWBKGB2L",
    bank_acc_name="Acme Corporation Ltd", currency_code="GBP",
    bank_country="GB", is_primary=True,
    effective_from=None, effective_to=None, deleted_at=None,
)]
ENTITY = SimpleNamespace(id=1, tenant_id=1, entity_id=10,
    country_code="GB", vat_id="GB987654321", region_code=None)
TAX_MASTER = [
    SimpleNamespace(id=1, tenant_id=1, is_active=True, deleted_at=None,
        country_code="GB", region_code=None, tax_type="VAT",
        tax_rate=20.0, tax_name="VAT Standard 20%",
        effective_from=None, effective_to=None),
    SimpleNamespace(id=2, tenant_id=1, is_active=True, deleted_at=None,
        country_code="GB", region_code=None, tax_type="VAT",
        tax_rate=5.0, tax_name="VAT Reduced 5%",
        effective_from=None, effective_to=None),
]
CURRENCY = {"GBP": {"minor_unit_value": "0.01"}, "USD": {"minor_unit_value": "0.01"}}

VAL_PO = [SimpleNamespace(id=200, tenant_id=1, po_number_canonical="PO-001",
    payment_terms=30, deleted_at=None)]


def make_doc(status="validated"):
    return SimpleNamespace(id=1001, tenant_id=1, entity_id=10,
        status=status, doc_type="invoice", tenant_timezone="Europe/London")


def make_ef(**kw):
    base = dict(
        sender_name="Acme Corporation Ltd",
        sender_name_canonical="ACMECORPORATIONLTD",
        sender_tax_id="GB123456715", sender_tax_id_canonical="GB123456715",
        bank_iban="GB29NWBK60161331926819",
        bank_iban_canonical="GB29NWBK60161331926819",
        bank_acc_no="31926819", bank_swift="NWBKGB2L",
        bank_acc_name="Acme Corporation Ltd",
        invoice_date=date(2025, 10, 1), due_date=date(2025, 10, 31),
        due_date_origin="invoice", service_start_date=None,
        service_end_date=None, payment_terms=30,
        po_number_canonical=None, currency="GBP",
        invoice_no="INV-TEST", total_amount=Decimal("120.00"),
        subtotal=Decimal("100.00"), tax_amount=Decimal("20.00"),
        tax_rate=Decimal("20.0"),
    )
    base.update(kw)
    return SimpleNamespace(**base)


def make_val_lines(amount="100.00", tax_amount="20.00"):
    return [SimpleNamespace(
        line_number=1, amount=Decimal(amount),
        tax_rate_per_item=Decimal("20.0"),
        tax_amount_per_item=Decimal(tax_amount),
        discount_amount_per_item=None,
    )]


def make_inv_header(currency="GBP", vendor_id=100, total_amount="100.00",
                    invoice_date=date(2025, 10, 1), status="validated"):
    return InvoiceHeader(id=1001, status=status,
        vendor_id=vendor_id, currency=currency,
        total_amount=Decimal(total_amount), invoice_date=invoice_date)


def make_inv_lines(unit_price="10.00", amount="100.00"):
    return [InvoiceLine(id=1,
        description="Software License - Annual",
        description_canonical="SOFTWARELICENSEANNUAL",
        sku="SW-LIC-001", sku_canonical="SWLIC001",
        quantity=Decimal("10"), unit_price=Decimal(unit_price),
        amount=Decimal(amount))]


def make_po(status="open", line_status="open", currency="GBP",
            vendor_id=100, invoiced_qty="0"):
    ph = POHeader(id=200, vendor_id=vendor_id, currency=currency, status=status)
    pl = [POLine(id=201,
        description="Software License - Annual",
        description_canonical="SOFTWARELICENSEANNUAL",
        sku="SW-LIC-001", sku_canonical="SWLIC001",
        quantity=Decimal("10"), invoiced_qty=Decimal(invoiced_qty),
        unit_price=Decimal("10.00"), item_type="services", status=line_status)]
    return ph, pl


def run_case(label, **kw):
    defaults = dict(
        document=make_doc(),
        extracted_fields=make_ef(),
        vendors=VENDORS,
        vendor_bank_accounts=VENDOR_BANK_ACCOUNTS,
        vendor_tax_ids=VENDOR_TAX_IDS,
        entity=ENTITY,
        line_items=make_val_lines(),
        purchase_orders=[],
        contracts=[],
        tax_master_rows=TAX_MASTER,
        currency_seed_map=CURRENCY,
        matching_invoice=make_inv_header(),
        matching_inv_lines=make_inv_lines(),
        contract_invoice=None,
        po=None, po_lines=None, gr_rows=None,
    )
    defaults.update(kw)
    try:
        r = run_invoice_pipeline(**defaults)
        mr = r.get("match_result")
        risk = [f.get("code", "") if isinstance(f, dict) else str(f)
                for f in r.get("risk_flags", [])]
        adv  = [f.get("code", "") if isinstance(f, dict) else str(f)
                for f in r.get("advisory_flags", [])]
        hexc = [e.exception_type for e in (getattr(mr, "header_exceptions", None) or [])]
        mexc = [e.exception_type for e in (getattr(mr, "match_exceptions", None) or [])]
        print(f"\n{'-'*62}")
        print(f"  {label}")
        print(f"  route={r.get('route')}  final={r.get('final_status')}  "
              f"zone={getattr(mr, 'match_zone', '-')}  "
              f"match_status={getattr(mr, 'overall_status', '-')}")
        if risk:  print(f"  risk_flags    : {risk}")
        if adv:   print(f"  advisory_flags: {adv}")
        if hexc:  print(f"  header_exc    : {hexc}")
        if mexc:  print(f"  match_exc     : {mexc}")
        if not risk and not adv and not hexc and not mexc:
            print(f"  (no flags / exceptions)")
    except Exception as ex:
        print(f"\n{'-'*62}")
        print(f"  {label}")
        print(f"  RAISED: {type(ex).__name__}: {ex}")


# ══════════════════════════════════════════════════════════════════════════════
print("=" * 62)
print("  EDGE CASE TESTS")
print("=" * 62)

# ── Routing edge cases ────────────────────────────────────────────────────────
ph, pl = make_po(status="open", line_status="cancelled")
run_case("EC01: PO open + all lines cancelled -> po_all_lines_closed",
    extracted_fields=make_ef(po_number_canonical="PO-001"),
    purchase_orders=VAL_PO, po=ph, po_lines=pl)

# ── Two-way header exceptions ─────────────────────────────────────────────────
ph2, pl2 = make_po(currency="USD")
run_case("EC02: Currency mismatch (invoice=GBP, PO=USD)",
    extracted_fields=make_ef(po_number_canonical="PO-001"),
    purchase_orders=VAL_PO, po=ph2, po_lines=pl2,
    matching_invoice=make_inv_header(currency="GBP"))

ph3, pl3 = make_po(vendor_id=999)
run_case("EC03: Vendor mismatch (invoice vendor=100, PO vendor=999)",
    extracted_fields=make_ef(po_number_canonical="PO-001"),
    purchase_orders=VAL_PO, po=ph3, po_lines=pl3)

ph4, pl4 = make_po(invoiced_qty="10")  # fully invoiced, available_qty=0
run_case("EC04: PO ceiling exhausted (invoiced_qty == quantity)",
    extracted_fields=make_ef(po_number_canonical="PO-001"),
    purchase_orders=VAL_PO, po=ph4, po_lines=pl4)

# ── Three-way GR checks ───────────────────────────────────────────────────────
ph5, pl5 = make_po()
gr_fraud = [GRLineItem(id=300, po_line_id=201,
    gr_date=date(2025, 11, 1),          # GR received AFTER invoice date
    inspection_status="accepted",
    quantity_accepted=Decimal("10"), quantity_received=Decimal("10"))]
run_case("EC05: Timing fraud — invoice 2025-10-01 before GR 2025-11-01",
    extracted_fields=make_ef(po_number_canonical="PO-001"),
    purchase_orders=VAL_PO, po=ph5, po_lines=pl5, gr_rows=gr_fraud)

ph6, pl6 = make_po()
gr_pending = [GRLineItem(id=300, po_line_id=201,
    gr_date=date(2025, 9, 28), inspection_status="pending",
    quantity_accepted=None, quantity_received=Decimal("10"))]
run_case("EC06: No accepted GR (all pending)",
    extracted_fields=make_ef(po_number_canonical="PO-001"),
    purchase_orders=VAL_PO, po=ph6, po_lines=pl6, gr_rows=gr_pending)

ph7, pl7 = make_po()
gr_rejected = [GRLineItem(id=300, po_line_id=201,
    gr_date=date(2025, 9, 28), inspection_status="rejected",
    quantity_accepted=Decimal("10"), quantity_received=Decimal("10"))]
run_case("EC07: GR inspection rejected",
    extracted_fields=make_ef(po_number_canonical="PO-001"),
    purchase_orders=VAL_PO, po=ph7, po_lines=pl7, gr_rows=gr_rejected)

# ── Contract edge cases ───────────────────────────────────────────────────────
rate_card = [RateCardItem(id=401,
    description="Software License - Annual",
    description_canonical="SOFTWARELICENSEANNUAL",
    unit_price=Decimal("10.00"), item_type="services")]

expired_c = [ContractRecord(id=400, tenant_id=1, vendor_id=100, entity_id=10,
    currency="GBP", status="active",
    effective_from=date(2020, 1, 1), effective_to=date(2021, 12, 31),
    rate_card_items=rate_card)]
c_inv = ContractInvoiceHeader(id=1001, tenant_id=1, entity_id=10,
    resolved_vendor_id=100, currency="GBP",
    invoice_date=date(2025, 10, 1), total_amount=Decimal("120.00"))
run_case("EC08: Contract expired (effective_to=2021-12-31)",
    contracts=expired_c, contract_invoice=c_inv)

budget_c = [ContractRecord(id=400, tenant_id=1, vendor_id=100, entity_id=10,
    currency="GBP", status="active",
    effective_from=date(2024, 1, 1),
    total_value=Decimal("500.00"),
    cumulative_billed_amount=Decimal("450.00"),
    rate_card_items=rate_card)]
c_inv2 = ContractInvoiceHeader(id=1001, tenant_id=1, entity_id=10,
    resolved_vendor_id=100, currency="GBP",
    invoice_date=date(2025, 10, 1), total_amount=Decimal("120.00"))
run_case("EC09: Contract budget exceeded (450 billed + 120 invoice > 500 limit)",
    contracts=budget_c, contract_invoice=c_inv2)

red_c = [ContractRecord(id=400, tenant_id=1, vendor_id=100, entity_id=10,
    currency="GBP", status="active", effective_from=date(2024, 1, 1),
    rate_card_items=rate_card)]
c_inv3 = ContractInvoiceHeader(id=1001, tenant_id=1, entity_id=10,
    resolved_vendor_id=100, currency="GBP",
    invoice_date=date(2025, 10, 1), total_amount=Decimal("180.00"))
run_case("EC10: Contract rate card red zone (invoice price 15.00 vs rate 10.00 = 50%)",
    contracts=red_c, contract_invoice=c_inv3,
    matching_invoice=make_inv_header(total_amount="150.00"),
    matching_inv_lines=make_inv_lines(unit_price="15.00", amount="150.00"),
    line_items=make_val_lines(amount="150.00", tax_amount="30.00"))

# ── Vendor / auth edge cases ──────────────────────────────────────────────────
deleted_v = [SimpleNamespace(
    id=100, tenant_id=1, legal_name="Acme Corporation Ltd",
    vendor_name="Acme Corporation Ltd", vendor_status="active",
    deleted_at="2023-01-01",
    billing_country="GB", billing_state=None,
    tax_registration_number="GB123456715", payment_terms=30,
    exemption_status="standard",
)]
ph11, pl11 = make_po()
run_case("EC11: Vendor soft-deleted (deleted_at set) — should be unknown_vendor",
    vendors=deleted_v,
    extracted_fields=make_ef(po_number_canonical="PO-001"),
    purchase_orders=VAL_PO, po=ph11, po_lines=pl11)

ph12, pl12 = make_po()
run_case("EC12: Invoice status=draft — should raise precondition error",
    document=make_doc(status="draft"),
    extracted_fields=make_ef(po_number_canonical="PO-001"),
    purchase_orders=VAL_PO, po=ph12, po_lines=pl12,
    matching_invoice=make_inv_header(status="draft"))

print(f"\n{'='*62}")
print("  Done.")