from typing import Any, Literal

from pydantic import BaseModel, Field

OpKind = Literal["item.create", "item.update", "item.delete", "items.clear_bought"]


class OpIn(BaseModel):
    # Vom Client vergeben, bevor gesendet wird. Grundlage der Idempotenz:
    # dieselbe op_id wird nie zweimal ausgefuehrt.
    op_id: str = Field(min_length=8, max_length=64)
    kind: OpKind
    payload: dict[str, Any] = Field(default_factory=dict)


class OpBatchIn(BaseModel):
    ops: list[OpIn] = Field(default_factory=list, max_length=200)


class OpResult(BaseModel):
    op_id: str
    status: Literal["applied", "duplicate", "rejected"]
    result_id: str | None = None
    error: str | None = None


class OpBatchOut(BaseModel):
    rev: int
    results: list[OpResult]