"""Mock banking data structures for IVR demonstrations.""" from __future__ import annotations import json from collections.abc import Iterable, Mapping from dataclasses import dataclass from pathlib import Path from types import MappingProxyType from typing import Any @dataclass(frozen=True) class Transaction: posted_at: str description: str amount: float @dataclass(frozen=True) class DepositAccount: account_number: str account_type: str balance: float available_balance: float interest_rate: float recent_transactions: tuple[Transaction, ...] @dataclass(frozen=True) class CreditCard: card_number: str product_name: str credit_limit: float statement_balance: float minimum_due: float payment_due_date: str rewards_earn_rate: str @dataclass(frozen=True) class LoanAccount: loan_id: str loan_type: str original_principal: float outstanding_balance: float interest_rate: float next_payment_due: str monthly_payment: float autopay_enabled: bool @dataclass(frozen=True) class RewardsSummary: tier: str points_balance: int expiring_next_statement: int cashback_available: float @dataclass(frozen=True) class CustomerProfile: customer_id: str pin: str full_name: str branch_name: str deposit_accounts: tuple[DepositAccount, ...] credit_cards: tuple[CreditCard, ...] loans: tuple[LoanAccount, ...] rewards: RewardsSummary class MockBankService: """Read-only mock of a retail banking core used by the IVR example.""" def __init__(self) -> None: self._customers: Mapping[str, CustomerProfile] = self._load_seed_data() def _load_seed_data(self) -> Mapping[str, CustomerProfile]: data_path = Path(__file__).with_name("data.json") try: with data_path.open(encoding="utf-8") as infile: data = json.load(infile) except FileNotFoundError as exc: raise FileNotFoundError(f"Mock bank data file not found: {data_path}") from exc customers: dict[str, CustomerProfile] = {} for customer_payload in data.get("customers", []): profile = self._build_customer_profile(customer_payload) customers[profile.customer_id] = profile return MappingProxyType(customers) def _build_customer_profile(self, data: Mapping[str, Any]) -> CustomerProfile: deposit_accounts = tuple( self._build_deposit_account(account_data) for account_data in data.get("deposit_accounts", []) ) credit_cards = tuple( self._build_credit_card(card_data) for card_data in data.get("credit_cards", []) ) loans = tuple(self._build_loan_account(loan_data) for loan_data in data.get("loans", [])) rewards_payload = data.get("rewards") or {} return CustomerProfile( customer_id=data["customer_id"], pin=data["pin"], full_name=data["full_name"], branch_name=data["branch_name"], deposit_accounts=deposit_accounts, credit_cards=credit_cards, loans=loans, rewards=RewardsSummary( tier=rewards_payload.get("tier", "Unknown"), points_balance=rewards_payload.get("points_balance", 0), expiring_next_statement=rewards_payload.get("expiring_next_statement", 0), cashback_available=rewards_payload.get("cashback_available", 0.0), ), ) def _build_deposit_account(self, data: Mapping[str, Any]) -> DepositAccount: transactions = tuple( self._build_transaction(txn) for txn in data.get("recent_transactions", []) ) return DepositAccount( account_number=data["account_number"], account_type=data["account_type"], balance=data["balance"], available_balance=data["available_balance"], interest_rate=data["interest_rate"], recent_transactions=transactions, ) def _build_credit_card(self, data: Mapping[str, Any]) -> CreditCard: return CreditCard( card_number=data["card_number"], product_name=data["product_name"], credit_limit=data["credit_limit"], statement_balance=data["statement_balance"], minimum_due=data["minimum_due"], payment_due_date=data["payment_due_date"], rewards_earn_rate=data["rewards_earn_rate"], ) def _build_loan_account(self, data: Mapping[str, Any]) -> LoanAccount: return LoanAccount( loan_id=data["loan_id"], loan_type=data["loan_type"], original_principal=data["original_principal"], outstanding_balance=data["outstanding_balance"], interest_rate=data["interest_rate"], next_payment_due=data["next_payment_due"], monthly_payment=data["monthly_payment"], autopay_enabled=data["autopay_enabled"], ) def _build_transaction(self, data: Mapping[str, Any]) -> Transaction: return Transaction( posted_at=data["posted_at"], description=data["description"], amount=data["amount"], ) # -- Authentication -------------------------------------------------------------- def list_customer_ids(self) -> tuple[str, ...]: return tuple(self._customers.keys()) def customer_exists(self, customer_id: str) -> bool: return customer_id in self._customers def authenticate(self, customer_id: str, pin: str) -> bool: profile = self._customers.get(customer_id) return bool(profile and profile.pin == pin) def get_profile(self, customer_id: str) -> CustomerProfile: try: return self._customers[customer_id] except KeyError as exc: raise KeyError(f"Unknown customer {customer_id}") from exc # -- Deposit accounts ------------------------------------------------------------ def list_deposit_accounts(self, customer_id: str) -> tuple[DepositAccount, ...]: return self.get_profile(customer_id).deposit_accounts def find_deposit_account(self, customer_id: str, account_number: str) -> DepositAccount | None: # noqa: UP007 for acct in self.list_deposit_accounts(customer_id): if acct.account_number == account_number: return acct return None def calculate_total_deposits(self, customer_id: str) -> float: return sum(acct.balance for acct in self.list_deposit_accounts(customer_id)) # -- Credit cards ---------------------------------------------------------------- def list_credit_cards(self, customer_id: str) -> tuple[CreditCard, ...]: return self.get_profile(customer_id).credit_cards def calculate_total_card_balance(self, customer_id: str) -> float: return sum(card.statement_balance for card in self.list_credit_cards(customer_id)) # -- Loans ----------------------------------------------------------------------- def list_loans(self, customer_id: str) -> tuple[LoanAccount, ...]: return self.get_profile(customer_id).loans def calculate_total_loan_balance(self, customer_id: str) -> float: return sum(loan.outstanding_balance for loan in self.list_loans(customer_id)) def upcoming_payments(self, customer_id: str) -> tuple[tuple[str, float, str], ...]: """Return tuples of (loan_id, amount, due_date).""" return tuple( (loan.loan_id, loan.monthly_payment, loan.next_payment_due) for loan in self.list_loans(customer_id) ) # -- Rewards --------------------------------------------------------------------- def get_rewards(self, customer_id: str) -> RewardsSummary: return self.get_profile(customer_id).rewards def format_currency(value: float) -> str: return f"${value:,.2f}" def format_transactions(transactions: Iterable[Transaction]) -> str: lines: list[str] = [] for txn in transactions: amount = format_currency(txn.amount) lines.append(f"{txn.posted_at} — {txn.description} ({amount})") return "\n".join(lines) if lines else "No recent activity."