"""同口径全年目标减累计实际；剩余期间保持整体，不暗填季节分配。"""
import json
from decimal import Decimal as D, InvalidOperation
from statistics import median


def finite(value):
    try:
        number = D(str(value))
    except (InvalidOperation, ValueError, TypeError) as exc:
        raise ValueError("invalid_numeric_input") from exc
    if not number.is_finite():
        raise ValueError("nonfinite_profit_input")
    return number


contract = {"symbol": "AAA", "year": 2026, "currency": "CNY", "scope": "parent_net_profit", "unit": "million"}


def remaining(target, actual, historical=(), constraint=None):
    for field in contract:
        if target[field] != actual[field]:
            raise ValueError("incompatible_"+field)
    if target["through_quarter"] != 4 or actual["through_quarter"] not in [1, 2, 3]:
        raise ValueError("invalid_period")
    required = finite(target["profit"])-finite(actual["profit"])
    quarters = list(range(actual["through_quarter"]+1, 5))
    history = [finite(x) for x in historical]
    benchmark = median(history) if history else None
    uplift = required/benchmark-1 if benchmark is not None and benchmark > 0 else None
    cap = finite(constraint) if constraint is not None else None
    return {"remaining_quarters": quarters, "required_total": str(required),
            "historical_median": str(benchmark) if benchmark is not None else None,
            "uplift": str(uplift) if uplift is not None else None,
            "exceeds_supplied_constraint": required > cap if cap is not None else None,
            "already_met": required <= 0, "quarter_allocation": None}


def profit_from_eps(eps, shares_million):
    if shares_million is None:
        return {"profit": None, "reason": "missing_share_assumption"}
    shares = finite(shares_million)
    if shares <= 0:
        raise ValueError("invalid_shares")
    return {"profit": str(finite(eps)*shares), "reason": None}


target = {**contract, "through_quarter": 4, "profit": "400"}
actual = {**contract, "through_quarter": 3, "profit": "250"}
main = remaining(target, actual, ["100", "120", "140"], "145")
assert main["required_total"] == "150" and main["uplift"] == "0.25"
assert main["exceeds_supplied_constraint"] is True
half = remaining(target, {**actual, "through_quarter": 2, "profit": "180"})
assert half["required_total"] == "220" and half["remaining_quarters"] == [3, 4] and half["quarter_allocation"] is None
met = remaining(target, {**actual, "profit": "450"})
assert met["required_total"] == "-50" and met["already_met"]
assert profit_from_eps("4", "100")["profit"] == "400"
assert profit_from_eps("4", None)["profit"] is None
for token in ["NaN", "Infinity", "-Infinity"]:
    for kwargs in [{"historical": [token]}, {"constraint": token}]:
        try:
            remaining(target, actual, **kwargs)
        except ValueError:
            pass
        else:
            raise AssertionError("非有限比较值必须阻断")
    try:
        remaining(target, {**actual, "profit": token})
    except ValueError:
        pass
    else:
        raise AssertionError("非有限实际必须阻断")
print(json.dumps({"nine_months": main, "half_year": half, "target_already_met": met,
                  "eps_without_shares": profit_from_eps("4", None)}, sort_keys=True))