from datetime import datetime
from decimal import Decimal

from pydantic import BaseModel, ConfigDict


class CustomerIn(BaseModel):
    name: str
    email: str


class CustomerOut(CustomerIn):
    model_config = ConfigDict(from_attributes=True)
    id: int
    created_at: datetime


class LineItemIn(BaseModel):
    description: str
    quantity: int = 1
    unit_price: Decimal = Decimal("0")


class LineItemOut(LineItemIn):
    model_config = ConfigDict(from_attributes=True)
    id: int
    invoice_id: int


class PaymentIn(BaseModel):
    amount: Decimal
    method: str = "cash"


class PaymentOut(PaymentIn):
    model_config = ConfigDict(from_attributes=True)
    id: int
    invoice_id: int
    paid_at: datetime


class InvoiceIn(BaseModel):
    number: str
    customer_id: int
    due_at: datetime | None = None
    status: str = "draft"


class InvoiceOut(InvoiceIn):
    model_config = ConfigDict(from_attributes=True)
    id: int
    issued_at: datetime


class InvoiceDetail(InvoiceOut):
    line_items: list[LineItemOut] = []
    payments: list[PaymentOut] = []
    customer: CustomerOut