"""
Pydantic model representing a structured assignment card.

Fields:
- title: short title of the task (string)
- subject: main topic or subject area (string, optional)
- deadline_hint: free‑form hint about due date (string, optional)
- deliverable_type: what is expected to be submitted (string, optional)
- grading_hints: list of strings describing evaluation criteria (list[str], optional)
"""
from __future__ import annotations

from typing import List, Optional

from pydantic import BaseModel, Field

class AssignmentCard(BaseModel):
    """Structured representation of an informal assignment description."""

    title: str = Field(..., description="Short title or main action of the task")
    subject: Optional[str] = Field(None, description="Primary subject or topic of the task")
    deadline_hint: Optional[str] = Field(
        None,
        description="Free‑form hint about when the task is due (e.g., 'к пятнице')",
    )
    deliverable_type: Optional[str] = Field(
        None, description="What should be submitted: report, code, presentation, etc."
    )
    grading_hints: List[str] = Field(
        default_factory=list,
        description="List of evaluation criteria mentioned in the text",
    )

    class Config:
        arbitrary_types_allowed = True
        json_schema_extra = {
            "example": {
                "title": "Мини‑отчёт по LangChain",
                "subject": "LangChain",
                "deadline_hint": "к пятнице",
                "deliverable_type": "отчёт",
                "grading_hints": ["полнота", "пример кода"],
            }
        }