import math

import pytest

from helpers.refractor_test_data import calculate_plays_needed


class TestCalculatePlaysNeeded:
    """Test the pure function that computes how many synthetic plays
    are needed to push a card's refractor value over the next tier
    threshold. The formulas are:
      - batter: each HR play = 9 value (1 PA + 4 TB * 2)
      - sp/rp:  each K play  = 4/3 value (1/3 IP + 1 K)
    """

    def test_batter_exact_threshold(self):
        """When the gap is exactly divisible by 9, no extra plays needed."""
        result = calculate_plays_needed(gap=27, card_type="batter")
        assert result["num_plays"] == 3
        assert result["total_value"] == 27
        assert result["value_per_play"] == 9

    def test_batter_rounds_up(self):
        """When gap isn't divisible by 9, round up to overshoot."""
        result = calculate_plays_needed(gap=10, card_type="batter")
        assert result["num_plays"] == 2  # ceil(10/9) = 2
        assert result["total_value"] == 18

    def test_batter_gap_of_one(self):
        """Even a gap of 1 requires one play."""
        result = calculate_plays_needed(gap=1, card_type="batter")
        assert result["num_plays"] == 1
        assert result["total_value"] == 9

    def test_sp_exact_threshold(self):
        """SP: each K play = 4/3 value."""
        result = calculate_plays_needed(gap=4, card_type="sp")
        assert result["num_plays"] == 3  # ceil(4 / (4/3)) = 3
        assert result["value_per_play"] == pytest.approx(4 / 3)

    def test_rp_same_as_sp(self):
        """RP uses the same formula as SP."""
        result = calculate_plays_needed(gap=4, card_type="rp")
        assert result["num_plays"] == 3

    def test_zero_gap_returns_one_play(self):
        """If already at threshold, still need 1 play to push over."""
        result = calculate_plays_needed(gap=0, card_type="batter")
        assert result["num_plays"] == 1