from decimal import Decimal
from typing import Any, Dict, List

CARD_LAST_DIGITS = "1234"
CARD_VALID_UNTIL = "2030-12-31"  # 12/30 para todas las tarjetas
VOUCHER_MAX_LEN = 20  # SAP rechaza VoucherNum más largo; VoucherNum = name de la orden de Shopify


class PaymentConfigError(Exception):
    """El pago no se puede armar (medio sin configurar, montos que no cuadran, etc.)."""


# ============================================================================
def transacciones_efectivas(transactions: List[Dict[str, Any]]) -> List[Dict[str, Any]]:
    """
    Transacciones que representan dinero realmente cobrado: status success y
    kind sale/capture. Se ignoran failure/pending y refund/void. Si una
    authorization tiene su capture (parent_id), solo cuenta la capture.
    """
    exitosas = [t for t in transactions if t.get("status") == "success"]
    autorizaciones_capturadas = {t.get("parent_id") for t in exitosas if t.get("kind") == "capture" and t.get("parent_id")}

    efectivas = []
    for t in exitosas:
        if t.get("kind") == "sale":
            efectivas.append(t)
        elif t.get("kind") == "capture":
            efectivas.append(t)
        # authorization sin capture y el resto de kinds no suman
    return [t for t in efectivas if t.get("id") not in autorizaciones_capturadas]


# ============================================================================
def _metodo(store_config: Dict[str, Any], gateway: str) -> Dict[str, Any]:
    metodos = store_config["sap"].get("payment_methods") or {}
    metodo = metodos.get(gateway)
    if not metodo:
        raise PaymentConfigError(f"Medio de pago '{gateway}' no está configurado en sap.payment_methods")
    return metodo


def construir_incoming_payment(
    order: Dict[str, Any],
    transactions: List[Dict[str, Any]],
    store_config: Dict[str, Any],
    invoice: Dict[str, Any],
    invoice_doc_entry: int,
    invoice_total: float,
) -> Dict[str, Any]:
    """
    Arma el JSON para POST IncomingPayments, aplicado a la Invoice de reserva
    ya creada (CardCode, CardName y fecha salen de esa Invoice).

    Los medios de pago salen de las transacciones efectivas (no de
    payment_gateway_names): cada una según sap.payment_methods[gateway]:
      - credit_card -> una línea en PaymentCreditCards
      - transfer    -> suma a TransferSum con su transfer_account
    La suma debe igualar el total de la Invoice.
    """
    series = store_config["sap"]["numbering_series"]["INCOMING_PAYMENT"]
    doc_date = invoice["DocDate"]

    efectivas = transacciones_efectivas(transactions)
    if not efectivas:
        raise PaymentConfigError("La orden no tiene transacciones de pago exitosas")

    tarjetas: List[Dict[str, Any]] = []
    transferencia = Decimal("0")
    cuentas_transfer = set()
    gateways: List[str] = []

    for t in efectivas:
        gateway = t.get("gateway")
        metodo = _metodo(store_config, gateway)
        monto = Decimal(str(t["amount"]))
        gateways.append(gateway)

        if metodo["type"] == "credit_card":
            if not metodo.get("credit_card"):
                raise PaymentConfigError(f"Medio de pago '{gateway}' sin tarjeta de crédito (credit_card) asociada")
            linea = {
                "CreditCard": metodo["credit_card"],
                "CreditCardNumber": CARD_LAST_DIGITS,
                "CardValidUntil": CARD_VALID_UNTIL,
                "VoucherNum": str(order.get("name") or "")[:VOUCHER_MAX_LEN],
                "CreditSum": float(monto),
                "CreditCur": "CLP",
                "CreditType": "cr_Regular",
                "NumOfPayments": metodo.get("num_of_payments", 1),
                "FirstPaymentDue": doc_date,
                "SplitPayments": "tYES" if metodo.get("split_payment") else "tNO",
            }
            if metodo.get("payment_method_code"):
                linea["PaymentMethodCode"] = metodo["payment_method_code"]
            tarjetas.append(linea)
        elif metodo["type"] == "transfer":
            if not metodo.get("transfer_account"):
                raise PaymentConfigError(f"Medio de pago '{gateway}' sin transfer_account")
            cuentas_transfer.add(metodo["transfer_account"])
            transferencia += monto
        else:
            raise PaymentConfigError(f"Medio de pago '{gateway}' con type inválido: {metodo['type']!r}")

    if len(cuentas_transfer) > 1:
        raise PaymentConfigError(f"Transferencias con cuentas distintas no soportado: {sorted(cuentas_transfer)}")

    total_pagado = transferencia + sum((Decimal(str(l["CreditSum"])) for l in tarjetas), Decimal("0"))
    if total_pagado != Decimal(str(invoice_total)):
        raise PaymentConfigError(f"Suma de pagos ({total_pagado}) no coincide con el total de la Invoice ({invoice_total})")

    payload: Dict[str, Any] = {
        "CardCode": invoice["CardCode"],
        "CardName": invoice["CardName"],
        "DocType": "rCustomer",
        "DocDate": doc_date,
        "Series": series,
        "DocCurrency": "CLP",
        "Remarks": " + ".join(dict.fromkeys(gateways)),
        "PaymentInvoices": [
            {
                "DocEntry": invoice_doc_entry,
                "InvoiceType": "it_Invoice",
                "SumApplied": invoice_total,
            }
        ],
    }

    if tarjetas:
        payload["PaymentCreditCards"] = tarjetas
    if transferencia:
        payload["TransferAccount"] = next(iter(cuentas_transfer))
        payload["TransferSum"] = float(transferencia)
        payload["TransferDate"] = doc_date
        payload["TransferReference"] = order.get("name")

    return payload