import math
from datetime import datetime, timedelta

import pytest

import draft_sap


# ============================================================================
# calcular_fecha_vencimiento
# ============================================================================
@pytest.mark.parametrize("condicion, esperado", [
    (None, "2026-01-10"),
    ({"NumberOfAdditionalDays": 30, "NumberOfAdditionalMonths": 0}, "2026-02-09"),
    ({"NumberOfAdditionalDays": 0, "NumberOfAdditionalMonths": 2}, "2026-03-11"),      # 2 meses = 60 días
    ({"NumberOfAdditionalDays": None, "NumberOfAdditionalMonths": None}, "2026-01-10"),
    ({"NumberOfAdditionalDays": 15, "NumberOfAdditionalMonths": 3}, "2026-01-25"),     # los días priman
])
def test_calcular_fecha_vencimiento(condicion, esperado):
    assert draft_sap.calcular_fecha_vencimiento("2026-01-10", condicion) == esperado


# ============================================================================
# validate_prices
# ============================================================================
def _delivery_note(line_total=100.0, pav=1.5, qty=10, almacen="A-X"):
    return [{
        "Series": "1", "DocNum": "9", "U_IDC_DESTINO": "Z1",
        "DocumentLines": [
            {"ItemCode": "FL10007", "LineTotal": line_total, "PriceAfterVAT": pav,
             "Quantity": qty, "WarehouseCode": almacen, "Weight1": 5},
            {"ItemCode": "OTRO", "LineTotal": 999, "PriceAfterVAT": 9, "Quantity": 9},  # no FL\d: se ignora
        ],
    }]


def _guia(numero="1"):
    return {"tipo": "09", "serie": "T001", "numero": numero}


@pytest.fixture
def sap(monkeypatch):
    """SAP simulado: devuelve la misma DeliveryNote para toda guía."""
    estado = {"dn": _delivery_note()}
    monkeypatch.setattr(draft_sap.sapb1_manager, "get_zonas", lambda: [{"Code": "Z1", "Name": "ZONA1"}])
    monkeypatch.setattr(draft_sap.sapb1_manager, "get_delivery_notes", lambda **k: estado["dn"])
    return estado


def test_precios_coinciden_usa_valores_de_sap(sap):
    factura = {"lineas": [{"cantidad": 1, "total_linea": 100.0, "guias_remision": [_guia()]}]}
    ok, resultados = draft_sap.validate_prices(factura)

    assert ok is True
    item = resultados[0]["guias_lt"][0]
    assert resultados[0]["ok"] is True
    assert (item["draft_quantity"], item["draft_price"]) == (10, 1.5)   # de SAP, no del XML
    assert item["zona"] == "ZONA1"
    assert item["warehouse_code"] == "A-X"
    assert item["weight1"] == 5.0


def test_precios_no_coinciden_usa_valores_del_xml(sap):
    factura = {"lineas": [{"cantidad": 4, "total_linea": 90.0, "guias_remision": [_guia()]}]}
    ok, resultados = draft_sap.validate_prices(factura)

    assert ok is False
    item = resultados[0]["guias_lt"][0]
    assert (item["draft_quantity"], item["draft_price"]) == (4, 22.5)   # 90 / 4


def test_varias_guias_de_una_linea_se_suman(sap):
    sap["dn"] = _delivery_note(line_total=60.0)
    factura = {"lineas": [{"cantidad": 1, "total_linea": 120.0, "guias_remision": [_guia("1"), _guia("2")]}]}
    ok, resultados = draft_sap.validate_prices(factura)

    assert ok is True
    assert resultados[0]["sap_price"] == 120.0
    assert len(resultados[0]["guias_lt"]) == 2


@pytest.mark.parametrize("total_xml, total_sap, coincide", [
    # un céntimo de diferencia: antes se aceptaba o se rechazaba según el ruido de la coma flotante
    (624.38, 624.39, True), (624.39, 624.38, True),
    (431.40, 431.41, True), (170.29, 170.30, True),      # estos dos la regla vieja los rechazaba
    (828.73, 828.74, True), (828.74, 828.73, True),
    (100.00, 100.01, True), (0.50, 0.51, True), (1.00, 1.01, True), (10.01, 10.00, True),
    # menos de un céntimo, o igual
    (100.00, 100.00, True), (100.005, 100.00, True), (1203.94, 1203.9399, True),
    # dos céntimos o más: no coincide
    (100.00, 100.02, False), (100.02, 100.00, False), (624.38, 624.40, False), (624.38, 674.38, False),
])
def test_tolerancia_de_un_centimo_es_determinista(sap, total_xml, total_sap, coincide):
    sap["dn"] = _delivery_note(line_total=total_sap)
    factura = {"lineas": [{"cantidad": 1, "total_linea": total_xml, "guias_remision": [_guia()]}]}

    todas_coinciden, resultados = draft_sap.validate_prices(factura)

    assert todas_coinciden is coincide and resultados[0]["ok"] is coincide


def test_cantidad_cero_no_se_valida(sap):
    factura = {"lineas": [{"cantidad": 0, "total_linea": 100.0, "guias_remision": [_guia()]}]}
    ok, resultados = draft_sap.validate_prices(factura)
    assert ok is False
    assert resultados[0]["label"] == "Cantidad cero, sin validar"
    assert resultados[0]["guias_lt"] == []


def test_linea_sin_guia_no_se_valida(sap):
    factura = {"lineas": [{"cantidad": 1, "total_linea": 100.0, "guias_remision": []}]}
    ok, resultados = draft_sap.validate_prices(factura)
    assert ok is False
    assert resultados[0]["label"] == "Sin guía de referencia"


def test_guia_inexistente_en_sap_queda_sin_validar(sap):
    sap["dn"] = []
    factura = {"lineas": [{"cantidad": 1, "total_linea": 100.0, "guias_remision": [_guia()]}]}
    ok, resultados = draft_sap.validate_prices(factura)
    assert ok is False
    assert resultados[0]["label"] == "Sin guías SAP"


def test_error_consultando_sap_invalida_la_linea(monkeypatch, sap):
    def falla(**k):
        raise RuntimeError("sin conexión")
    monkeypatch.setattr(draft_sap.sapb1_manager, "get_delivery_notes", falla)
    factura = {"lineas": [{"cantidad": 1, "total_linea": 0.0, "guias_remision": [_guia()]}]}
    ok, resultados = draft_sap.validate_prices(factura)
    assert ok is False                     # aunque 0 == 0, el error obliga a ok=False
    assert resultados[0]["guias_lt"][0]["line_total"] == 0.0


# ============================================================================
# build_sap_draft
# ============================================================================
def _factura(fecha_emision, **extra):
    base = {
        "serie": "F002", "numero": "486", "tipo": "01", "total_factura": 118.0,
        "fecha_emision": fecha_emision, "ruc_emisor": "20537929520",
        "razon_social_emisor": "TRANSPORTES SA", "tiene_detraccion": False,
        "ruta_red_pdf": "\\\\srv\\a.pdf", "ruta_red_xml": "\\\\srv\\a.xml",
        "lineas": [
            {"descripcion": "Servicio A", "valor_referencial": 10.5},
            {"descripcion": "Servicio B", "valor_referencial": 4.5},
        ],
    }
    base.update(extra)
    return base


def _resultados(draft_price=1.23456789, draft_quantity=3):
    item = {"guia": {"tipo": "09", "serie": "T001", "numero": "100"},
            "draft_price": draft_price, "draft_quantity": draft_quantity, "warehouse_code": "A-X"}
    return [{"guias_lt": [item]}, {"guias_lt": []}]


@pytest.fixture
def condicion_pago(monkeypatch):
    monkeypatch.setattr(draft_sap.sapb1_manager, "obtener_condicion_pago",
                        lambda card_code: {"NumberOfAdditionalDays": 30})


def test_draft_cabecera_y_linea(condicion_pago):
    hoy = datetime.now()
    draft = draft_sap.build_sap_draft(_factura(hoy.strftime("%Y-%m-%d")), _resultados())

    assert draft["CardCode"] == "PL20537929520"
    assert draft["NumAtCard"] == "01F002-486"
    assert draft["DocDate"] == hoy.strftime("%Y-%m-%d")
    assert draft["DocDueDate"] == (hoy + timedelta(days=30)).strftime("%Y-%m-%d")
    assert draft["U_IDC_VALREF"] == 15.0                   # suma del XML
    assert draft["U_IDC_NUMGR"] == "09T001-100"
    assert draft["U_VS_ANEXO_PDF"] == "\\\\srv\\a.pdf"
    assert len(draft["DocumentLines"]) == 1                # la línea sin guías se omite

    linea = draft["DocumentLines"][0]
    assert linea["Quantity"] == 3
    assert linea["PriceAfterVAT"] == math.trunc(1.23456789 * 1_000_000) / 1_000_000 == 1.234567
    assert linea["U_IDC_GRFLETE"] == "09T001-100"
    assert linea["WarehouseCode"] == "A-X"

    vencimiento = (hoy + timedelta(days=30)).strftime("%Y-%m-%d")
    assert draft["DocumentInstallments"] == [          # la cuota vence en la fecha de vencimiento, no en la de emisión
        {"DueDate": vencimiento, "Total": 118.0, "InstallmentId": 1,
         "U_VS_TIPOCUOTA": "N", "U_VS_TIPOSERVICIO": ""},
    ]


def test_item_code_segun_mes_de_emision(condicion_pago):
    hoy = datetime.now()
    mes_anterior = (hoy.replace(day=1) - timedelta(days=1)).strftime("%Y-%m-%d")

    actual = draft_sap.build_sap_draft(_factura(hoy.strftime("%Y-%m-%d")), _resultados())
    anterior = draft_sap.build_sap_draft(_factura(mes_anterior), _resultados())

    assert actual["DocumentLines"][0]["ItemCode"] == "C103002"
    assert anterior["DocumentLines"][0]["ItemCode"] == "C103002-A"


def test_draft_con_detraccion_genera_dos_cuotas(condicion_pago):
    fecha = datetime.now().strftime("%Y-%m-%d")
    factura = _factura(fecha, tiene_detraccion=True, codigo_detraccion="004",
                       porcentaje_detraccion=12, monto_detraccion=11.2)
    draft = draft_sap.build_sap_draft(factura, _resultados())

    detraccion, neto = draft["DocumentInstallments"]
    assert detraccion["DueDate"] == neto["DueDate"] == draft["DocDueDate"]      # ambas cuotas vencen en el vencimiento
    assert (detraccion["Total"], detraccion["U_VS_TIPOCUOTA"], detraccion["U_VS_TIPOSERVICIO"]) == (12, "D", "00402")
    assert (neto["Total"], neto["U_VS_TIPOCUOTA"]) == (106.0, "N")     # 118 - ceil(11.2)
    assert draft["U_VS_AFEDET"] == "Y"
    assert draft["U_VS_CODSER"] == "00402"
    assert draft["U_VS_PORDET"] == 12


def test_draft_sin_guias_validadas_queda_sin_lineas(condicion_pago):
    fecha = datetime.now().strftime("%Y-%m-%d")
    draft = draft_sap.build_sap_draft(_factura(fecha), [{"guias_lt": []}, {"guias_lt": []}])
    assert draft["DocumentLines"] == []
    assert draft["U_IDC_NUMGR"] == ""


def test_draft_sin_condicion_de_pago_vence_el_dia_de_contabilizacion(monkeypatch):
    monkeypatch.setattr(draft_sap.sapb1_manager, "obtener_condicion_pago", lambda c: None)
    fecha = datetime.now().strftime("%Y-%m-%d")
    draft = draft_sap.build_sap_draft(_factura(fecha), _resultados())
    assert draft["DocDueDate"] == draft["DocDate"]
    assert draft["DocumentInstallments"][0]["DueDate"] == draft["DocDate"]


# ============================================================================
# obtener_valor_referencial_sap
# ============================================================================
def test_valor_referencial_consulta_una_vez_por_guia(monkeypatch):
    llamadas = []
    monkeypatch.setattr(draft_sap.hana_manager, "obtener_valor_referencial",
                        lambda serie, numero: llamadas.append((serie, numero)) or 7.5)
    g = {"tipo": "09", "serie": "T001", "numero": "1"}
    factura = {"lineas": [
        {"guias_remision": [g]},
        {"guias_remision": [g, {"tipo": "09", "serie": "T001", "numero": "2"}]},
    ]}

    resultado = draft_sap.obtener_valor_referencial_sap(factura)

    assert llamadas == [("T001", "1"), ("T001", "2")]
    assert [r["valor_sap"] for r in resultado] == [7.5, 7.5]


# ============================================================================
# Caídas de SAP y errores de consulta
# ============================================================================
def test_validate_prices_deja_pasar_una_caida_de_sap(sap, monkeypatch):
    def cae(**k):
        raise draft_sap.sapb1_manager.SapNoDisponible("sin conexión")
    monkeypatch.setattr(draft_sap.sapb1_manager, "get_delivery_notes", cae)
    factura = {"lineas": [{"cantidad": 1, "total_linea": 100.0, "guias_remision": [_guia()]}]}

    with pytest.raises(draft_sap.sapb1_manager.SapNoDisponible):         # no se disfraza de "error de la guía"
        draft_sap.validate_prices(factura)


def test_validate_prices_marca_el_error_de_consulta_de_la_guia(sap, monkeypatch):
    def falla(**k):
        raise ValueError("respuesta rara de SAP")
    monkeypatch.setattr(draft_sap.sapb1_manager, "get_delivery_notes", falla)
    factura = {"lineas": [{"cantidad": 1, "total_linea": 100.0, "guias_remision": [_guia()]}]}

    _, resultados = draft_sap.validate_prices(factura)

    assert resultados[0]["guias_lt"][0]["error"] == "respuesta rara de SAP"
    assert draft_sap.hay_error_de_consulta(resultados) == "respuesta rara de SAP"


def test_hay_error_de_consulta_sin_errores():
    assert draft_sap.hay_error_de_consulta([]) is None
    assert draft_sap.hay_error_de_consulta([{"guias_lt": [{"guia": {}, "line_total": 0.0}]}, {"guias_lt": []}]) is None


def test_hana_disponible(monkeypatch):
    cerrada = []

    class Conexion:
        def close(self):
            cerrada.append(True)

    monkeypatch.setattr(draft_sap.hana_manager, "get_connection", lambda: Conexion())
    assert draft_sap.hana_disponible() is True and cerrada == [True]        # abre y cierra: no deja conexiones colgando

    monkeypatch.setattr(draft_sap.hana_manager, "get_connection", lambda: None)
    assert draft_sap.hana_disponible() is False