"""API schemas (Pydantic) for Child.

Schemas validate request bodies and shape responses. Separate from domain entities
so the wire format can evolve independently.
"""

from datetime import date, datetime
from uuid import UUID

from pydantic import BaseModel, Field, field_validator

from app.entities.child import Child


class ChildCreate(BaseModel):
    workspace_id: UUID
    name: str = Field(min_length=1, max_length=255)
    birth_date: date
    preschool_start_date: date | None = None
    preschool_planning_days_per_year: int = Field(default=6, ge=0, le=30)

    @field_validator("preschool_start_date")
    @classmethod
    def validate_preschool_date(cls, v: date | None, info) -> date | None:
        """Preschool start date must be after birth date if both provided."""
        if v is None:
            return v
        birth_date = info.data.get("birth_date")
        if birth_date and v <= birth_date:
            raise ValueError("preschool_start_date must be after birth_date")
        return v


class ChildUpdate(BaseModel):
    """Partial update — all fields optional."""

    name: str | None = Field(None, min_length=1, max_length=255)
    birth_date: date | None = None
    preschool_start_date: date | None = None
    preschool_planning_days_per_year: int | None = Field(None, ge=0, le=30)

    @field_validator("preschool_start_date")
    @classmethod
    def validate_preschool_date(cls, v: date | None, info) -> date | None:
        """Preschool start date must be after birth date if both provided."""
        if v is None:
            return v
        birth_date = info.data.get("birth_date")
        if birth_date and v <= birth_date:
            raise ValueError("preschool_start_date must be after birth_date")
        return v


class ChildResponse(BaseModel):
    id: UUID
    workspace_id: UUID
    name: str
    birth_date: date
    preschool_start_date: date | None
    preschool_planning_days_per_year: int
    created_at: datetime | None

    @classmethod
    def from_entity(cls, entity: Child) -> "ChildResponse":
        return cls(
            id=entity.id,
            workspace_id=entity.workspace_id,
            name=entity.name,
            birth_date=entity.birth_date,
            preschool_start_date=entity.preschool_start_date,
            preschool_planning_days_per_year=entity.preschool_planning_days_per_year,
            created_at=entity.created_at,
        )