"""从已冻结的任职依据取岗位，回补历史工资不改当前人员档案。"""

from sqlalchemy import select

from app.core.exceptions import BadRequestError
from app.models import PayrollInput


def role_on(person, day):
    if not person:
        return None
    month = str(day)[:7]
    for period in person.get("role_history", []):
        if period["start_month"] <= month <= period["end_month"]:
            return period["role_code"]
    return person.get("role_code")


def input_role(values, personnel_id, day):
    people = values.get("facts", {}).get("personnel", {})
    codes = {
        role_on(people[source_id], day)
        for source_id, target_id in values.get("maps", {}).get("personnel", {}).items()
        if target_id == personnel_id and source_id in people
    }
    if len(codes) > 1:
        raise BadRequestError("同一人员的历史岗位依据冲突，请先核实任职资料")
    return next(iter(codes), None)


def frozen_roles(session, rows, day):
    """按入结台账引用的资料版本解析任职，冲突时拒绝猜测。"""
    inputs = {}
    for row in rows:
        snapshot = row.snapshot_json or {}
        if snapshot.get("engine") == "FIFO" and snapshot.get("input_id"):
            inputs.setdefault(snapshot["input_id"], set()).add(row.personnel_id)
    result = {}
    for record in session.scalars(select(PayrollInput).where(PayrollInput.id.in_(inputs))):
        for pid in inputs[record.id]:
            role = input_role(record.data_json, pid, day)
            if role is None:
                raise BadRequestError("月结人员的历史岗位依据缺失，请先核实任职资料")
            if pid in result and result[pid] != role:
                raise BadRequestError("同一人员的历史岗位依据冲突，请先核实任职资料")
            result[pid] = role
    return result