"""API schemas (Pydantic) for LeaveWish.

Schemas validate request bodies and shape responses. Separate from domain entities
so the wire format can evolve independently. Business-rule validation (e.g. the
parent_mode / parent_personal_data_uuid pairing) lives in the service, not here —
these schemas only enforce shape and range.
"""

from datetime import datetime
from uuid import UUID

from pydantic import BaseModel, Field

from app.entities.leave_wish import LeaveWish


class LeaveWishCreate(BaseModel):
    workspace_id: UUID
    child_id: UUID | None = None
    name: str = Field(min_length=1, max_length=255)
    # i18n message key when `name` came from a preset (e.g.
    # "wishEditor.presetSommar") — see app/entities/leave_wish.py. Stored
    # alongside the translated `name` so the frontend can re-translate it;
    # not validated against a key catalogue here (that's a frontend concern).
    name_message_key: str | None = Field(default=None, max_length=255)

    window_start_month: int = Field(ge=1, le=12)
    window_start_day: int = Field(ge=1, le=31)
    window_end_month: int = Field(ge=1, le=12)
    window_end_day: int = Field(ge=1, le=31)

    target_weeks: int = Field(ge=1, le=52)
    # A calendar-drawn period is not a whole number of weeks. None (default)
    # falls back to `target_weeks * 7` — see `LeaveWish.target_span_days()`.
    target_days: int | None = Field(default=None, ge=1)
    recurrence: str = "once"  # 'yearly' | 'once'
    first_year: int = Field(ge=2000, le=2200)
    last_year: int | None = Field(default=None, ge=2000, le=2200)

    priority: int = Field(default=1, ge=1)
    parent_mode: str = "either"  # 'either' | 'both' | 'specific'
    parent_personal_data_uuid: UUID | None = None

    # PLANNING_ENGINE_SPEC.md §10.1 — 'fixed': window_start_*/window_end_* are the
    # exact placement (default). 'flexible': the same fields describe the
    # bounding range the allocator searches within for the best-costing window.
    window_mode: str = "fixed"  # 'fixed' | 'flexible'


class LeaveWishUpdate(BaseModel):
    """Partial update — all fields optional; only provided fields are changed."""

    child_id: UUID | None = None
    name: str | None = Field(None, min_length=1, max_length=255)
    # Present + null in the payload means "clear it"; absent means "leave
    # unchanged" (see `model_fields_set` handling in the router). The service
    # also clears this automatically whenever `name` actually changes, so a
    # caller can never forget to and leave a stale key pointing at old text.
    name_message_key: str | None = Field(default=None, max_length=255)

    window_start_month: int | None = Field(None, ge=1, le=12)
    window_start_day: int | None = Field(None, ge=1, le=31)
    window_end_month: int | None = Field(None, ge=1, le=12)
    window_end_day: int | None = Field(None, ge=1, le=31)

    target_weeks: int | None = Field(None, ge=1, le=52)
    # Present + null means "clear it" (fall back to target_weeks); absent
    # means "leave unchanged" — same convention as the other nullable fields
    # on this model (see `_clear_*` handling in `LeaveWishService.update`).
    target_days: int | None = Field(default=None, ge=1)
    recurrence: str | None = None
    first_year: int | None = Field(None, ge=2000, le=2200)
    last_year: int | None = Field(None, ge=2000, le=2200)

    priority: int | None = Field(None, ge=1)
    parent_mode: str | None = None
    parent_personal_data_uuid: UUID | None = None

    window_mode: str | None = None  # 'fixed' | 'flexible'


class LeaveWishResponse(BaseModel):
    id: UUID
    workspace_id: UUID
    child_id: UUID | None
    name: str
    name_message_key: str | None

    window_start_month: int
    window_start_day: int
    window_end_month: int
    window_end_day: int

    target_weeks: int
    target_days: int | None
    recurrence: str
    first_year: int
    last_year: int | None

    priority: int
    parent_mode: str
    parent_personal_data_uuid: UUID | None

    window_mode: str

    created_at: datetime | None
    updated_at: datetime | None

    @classmethod
    def from_entity(cls, entity: LeaveWish) -> "LeaveWishResponse":
        return cls(
            id=entity.id,
            workspace_id=entity.workspace_id,
            child_id=entity.child_id,
            name=entity.name,
            name_message_key=entity.name_message_key,
            window_start_month=entity.window_start_month,
            window_start_day=entity.window_start_day,
            window_end_month=entity.window_end_month,
            window_end_day=entity.window_end_day,
            target_weeks=entity.target_weeks,
            target_days=entity.target_days,
            recurrence=entity.recurrence,
            first_year=entity.first_year,
            last_year=entity.last_year,
            priority=entity.priority,
            parent_mode=entity.parent_mode,
            parent_personal_data_uuid=entity.parent_personal_data_uuid,
            window_mode=entity.window_mode,
            created_at=entity.created_at,
            updated_at=entity.updated_at,
        )