import uuid
from datetime import date as DateType, datetime
from decimal import Decimal
from typing import Literal

from pydantic import BaseModel, Field

TransactionType = Literal["income", "expense", "transfer", "investment"]
TransactionStatus = Literal["pending", "cleared", "reconciled", "void"]


class TransactionCreate(BaseModel):
    account_id: uuid.UUID
    transfer_account_id: uuid.UUID | None = None
    category_id: uuid.UUID | None = None
    type: TransactionType
    status: TransactionStatus = "cleared"
    amount: Decimal
    currency: str = Field(default="GBP", min_length=3, max_length=10)
    date: DateType
    description: str = Field(..., min_length=1, max_length=500)
    merchant: str | None = None
    notes: str | None = None
    tags: list[str] = []
    is_recurring: bool = False
    recurring_rule: dict | None = None


class TransactionUpdate(BaseModel):
    category_id: uuid.UUID | None = None
    status: TransactionStatus | None = None
    amount: Decimal | None = None
    date: DateType | None = None
    description: str | None = Field(default=None, min_length=1, max_length=500)
    merchant: str | None = None
    notes: str | None = None
    tags: list[str] | None = None


class TransactionFilter(BaseModel):
    account_id: uuid.UUID | None = None
    category_id: uuid.UUID | None = None
    type: TransactionType | None = None
    status: TransactionStatus | None = None
    date_from: DateType | None = None
    date_to: DateType | None = None
    min_amount: Decimal | None = None
    max_amount: Decimal | None = None
    search: str | None = None
    tags: list[str] = []
    page: int = Field(default=1, ge=1)
    page_size: int = Field(default=50, ge=1, le=200)


class TransactionResponse(BaseModel):
    id: uuid.UUID
    account_id: uuid.UUID
    transfer_account_id: uuid.UUID | None
    category_id: uuid.UUID | None
    type: str
    status: str
    amount: Decimal
    amount_base: Decimal | None
    currency: str
    base_currency: str
    exchange_rate: Decimal | None
    date: DateType
    description: str
    merchant: str | None
    notes: str | None
    tags: list[str]
    is_recurring: bool
    attachment_refs: list[dict] = []
    created_at: datetime
    updated_at: datetime

    model_config = {"from_attributes": True}