"""Additional unit tests for scoring edge cases."""
from __future__ import annotations

import pytest

from prometheus.domain.entities import EvalResult, Trajectory
from prometheus.domain.scoring import normalize_score, should_accept


def _make_eval(scores: list[float]) -> EvalResult:
    return EvalResult(
        scores=scores,
        feedbacks=[""] * len(scores),
        trajectories=[
            Trajectory(f"in{i}", f"out{i}", s, "", "p")
            for i, s in enumerate(scores)
        ],
    )


class TestShouldAcceptEdgeCases:
    """Extended edge-case tests for should_accept."""

    def test_tiny_improvement_accepted(self) -> None:
        old = _make_eval([0.5])
        new = _make_eval([0.5001])
        assert should_accept(old, new) is True

    def test_tiny_improvement_below_threshold(self) -> None:
        old = _make_eval([0.5])
        new = _make_eval([0.5001])
        assert should_accept(old, new, min_improvement=0.01) is False

    def test_zero_scores_equal(self) -> None:
        old = _make_eval([0.0, 0.0])
        new = _make_eval([0.0, 0.0])
        assert should_accept(old, new) is False

    def test_negative_to_zero_not_accepted(self) -> None:
        """Scores should be [0,1] but test should_accept with edge values."""
        old = _make_eval([-0.1])
        new = _make_eval([0.0])
        assert should_accept(old, new) is True

    def test_large_improvement(self) -> None:
        old = _make_eval([0.0, 0.0, 0.0])
        new = _make_eval([1.0, 1.0, 1.0])
        assert should_accept(old, new) is True

    def test_single_score_improvement(self) -> None:
        old = _make_eval([0.4])
        new = _make_eval([0.5])
        assert should_accept(old, new) is True

    def test_min_improvement_exactly_met(self) -> None:
        """When improvement exactly equals min_improvement, still rejected (strict >)."""
        old = _make_eval([0.5])
        new = _make_eval([0.7])
        assert should_accept(old, new, min_improvement=0.2) is False

    def test_min_improvement_just_over(self) -> None:
        old = _make_eval([0.5])
        new = _make_eval([0.7001])
        assert should_accept(old, new, min_improvement=0.2) is True


class TestNormalizeScoreEdgeCases:
    """Extended edge-case tests for normalize_score."""

    def test_exact_bounds(self) -> None:
        assert normalize_score(0.0) == 0.0
        assert normalize_score(1.0) == 1.0

    def test_very_large_value(self) -> None:
        assert normalize_score(1e10) == 1.0

    def test_very_negative_value(self) -> None:
        assert normalize_score(-1e10) == 0.0

    def test_custom_bounds_at_edges(self) -> None:
        assert normalize_score(5.0, min_val=0.0, max_val=10.0) == 5.0
        assert normalize_score(0.0, min_val=0.0, max_val=10.0) == 0.0
        assert normalize_score(10.0, min_val=0.0, max_val=10.0) == 10.0

    def test_negative_custom_range(self) -> None:
        assert normalize_score(0.0, min_val=-5.0, max_val=5.0) == 0.0
        assert normalize_score(-3.0, min_val=-5.0, max_val=5.0) == -3.0
        assert normalize_score(-10.0, min_val=-5.0, max_val=5.0) == -5.0

    def test_zero_span_range(self) -> None:
        """When min == max, clamps to min."""
        assert normalize_score(5.0, min_val=5.0, max_val=5.0) == 5.0
        assert normalize_score(0.0, min_val=5.0, max_val=5.0) == 5.0

    def test_fractional_score(self) -> None:
        assert normalize_score(0.3333) == pytest.approx(0.3333)