"""Pins for the 2026-09-21 switch of the competitors to the library.

REGRESSION: our Chandrupatla stopped on a bracket twice as wide as every other method
(tl = tol/span > 1/2 with tol = xtol), and best_of let that looser run into the
reported numbers.  The benchmark now uses the library alone, and our implementation -
kept for the timing section and the traced mirror - must agree with it exactly.
"""
from __future__ import annotations

import math

import pytest
from scipy.optimize._tstutils import _APS_TESTS_DICTS, _CHANDRUPATLA_TESTS_DICTS

from simroot.baselines import (BRENT_BASELINE, CHANDRUPATLA_BASELINE, brent_scipy,
                               chandrupatla, chandrupatla_lib)

XTOL, MAXFEV = 1e-12, 200


def _problems():
    out = []
    for d in _APS_TESTS_DICTS[::7]:
        f = (lambda ff, aa: lambda t: ff(t, *aa))(d["f"], d.get("args", ()))
        out.append((d["ID"], f, float(d["bracket"][0]), float(d["bracket"][1])))
    for d in _CHANDRUPATLA_TESTS_DICTS[::3]:
        out.append((d["ID"], d["f"], float(d["bracket"][0]), float(d["bracket"][1])))
    return out


def test_the_benchmark_competitors_are_the_library():
    assert CHANDRUPATLA_BASELINE is chandrupatla_lib
    assert BRENT_BASELINE is brent_scipy


def test_the_sweep_uses_them():
    import sweep_full
    assert sweep_full.BASELINES["chandrupatla"] is chandrupatla_lib
    assert sweep_full.BASELINES["brent"] is brent_scipy


@pytest.mark.parametrize("pid,f,a,b", _problems())
def test_our_chandrupatla_spends_exactly_what_the_library_spends(pid, f, a, b):
    """The tolerance fix, pinned: same evaluation count and same verdict."""
    x1, n1, c1 = chandrupatla(f, a, b, XTOL, MAXFEV)
    x2, n2, c2 = chandrupatla_lib(f, a, b, XTOL, MAXFEV)
    assert (n1, bool(c1)) == (n2, bool(c2)), (pid, n1, n2)
    if c1 and c2 and math.isfinite(x1) and math.isfinite(x2):
        assert abs(x1 - x2) <= 2 * XTOL + 1e-15 * max(1.0, abs(x1))


def test_our_chandrupatla_no_longer_stops_on_a_double_width_bracket():
    """On a smooth problem the looser rule saved an evaluation; with the fix our count
    must equal the library's rather than undercut it."""
    f = lambda t: math.exp(t) - 2.0          # noqa: E731
    _x, n_ours, _c = chandrupatla(f, 0.0, 3.0, XTOL, MAXFEV)
    _x, n_lib, _c = chandrupatla_lib(f, 0.0, 3.0, XTOL, MAXFEV)
    assert n_ours == n_lib