"""Add work_start_date + annual-leave balance fields to identity_persons.

Revision ID: 163
Revises: 162
Create Date: 2026-05-14

Adds five columns the HR Tools / 年假计算器 feature needs:

- ``work_start_date`` — 参加工作日期 (社会工龄 N 起点). Distinct from
  ``hire_date`` (司龄 S 起点) — first job ever, not first day at this
  company. Sourced from SuccessFactors ``EmpEmployment.originalStartDate``
  via the full-employee sync; HR can override in the calculator.
- ``annual_leave_carry_legal_days`` — 上年结转法定年假
- ``annual_leave_carry_welfare_days`` — 上年结转福利年假
- ``annual_leave_used_legal_days`` — 当年已休法定年假
- ``annual_leave_used_welfare_days`` — 当年已休福利年假

All five default NULL so older rows aren't synthetically zeroed. The
calculator treats NULL as "HR must input"; sync writes when SF
TimeAccount data is available, otherwise leaves NULL.

DECIMAL(4,1) — supports the 0.5-step rounding rule with one decimal of
precision; range covers the 15-day cap with headroom.
"""
from __future__ import annotations

import sqlalchemy as sa
from alembic import op

revision = "163"
down_revision = "162"
branch_labels = None
depends_on = None


def upgrade() -> None:
    op.add_column(
        "identity_persons",
        sa.Column("work_start_date", sa.Date(), nullable=True),
    )
    op.add_column(
        "identity_persons",
        sa.Column(
            "annual_leave_carry_legal_days",
            sa.Numeric(4, 1),
            nullable=True,
        ),
    )
    op.add_column(
        "identity_persons",
        sa.Column(
            "annual_leave_carry_welfare_days",
            sa.Numeric(4, 1),
            nullable=True,
        ),
    )
    op.add_column(
        "identity_persons",
        sa.Column(
            "annual_leave_used_legal_days",
            sa.Numeric(4, 1),
            nullable=True,
        ),
    )
    op.add_column(
        "identity_persons",
        sa.Column(
            "annual_leave_used_welfare_days",
            sa.Numeric(4, 1),
            nullable=True,
        ),
    )


def downgrade() -> None:
    op.drop_column("identity_persons", "annual_leave_used_welfare_days")
    op.drop_column("identity_persons", "annual_leave_used_legal_days")
    op.drop_column("identity_persons", "annual_leave_carry_welfare_days")
    op.drop_column("identity_persons", "annual_leave_carry_legal_days")
    op.drop_column("identity_persons", "work_start_date")