"""Tests for the safe calculator tool (issue #52)."""

from __future__ import annotations

import math

from timmy.tools import calculator

# ── Basic arithmetic ──────────────────────────────────────────────


class TestBasicArithmetic:
    def test_addition(self):
        assert calculator("2 + 3") == "5"

    def test_subtraction(self):
        assert calculator("10 - 4") == "6"

    def test_multiplication(self):
        assert calculator("347 * 829") == str(347 * 829)

    def test_division(self):
        assert calculator("10 / 3") == str(10 / 3)

    def test_floor_division(self):
        assert calculator("10 // 3") == "3"

    def test_modulo(self):
        assert calculator("10 % 3") == "1"

    def test_exponent(self):
        assert calculator("2**10") == "1024"

    def test_negative_number(self):
        assert calculator("-5 + 3") == "-2"

    def test_unary_plus(self):
        assert calculator("+5") == "5"


# ── Parentheses and precedence ────────────────────────────────────


class TestPrecedence:
    def test_nested_parens(self):
        assert calculator("(2 + 3) * (4 + 1)") == "25"

    def test_deep_nesting(self):
        assert calculator("((1 + 2) * (3 + 4)) + 5") == "26"

    def test_operator_precedence(self):
        assert calculator("2 + 3 * 4") == "14"


# ── Math module functions ─────────────────────────────────────────


class TestMathFunctions:
    def test_sqrt(self):
        assert calculator("math.sqrt(144)") == "12.0"

    def test_log(self):
        assert calculator("math.log(100, 10)") == str(math.log(100, 10))

    def test_sin(self):
        assert calculator("math.sin(0)") == "0.0"

    def test_pi(self):
        assert calculator("math.pi") == str(math.pi)

    def test_e(self):
        assert calculator("math.e") == str(math.e)

    def test_ceil(self):
        assert calculator("math.ceil(4.3)") == "5"

    def test_floor(self):
        assert calculator("math.floor(4.7)") == "4"

    def test_bare_sqrt(self):
        assert calculator("sqrt(16)") == "4.0"


# ── Allowed builtins ──────────────────────────────────────────────


class TestAllowedBuiltins:
    def test_abs(self):
        assert calculator("abs(-42)") == "42"

    def test_round(self):
        assert calculator("round(3.14159, 2)") == "3.14"

    def test_min(self):
        assert calculator("min(3, 1, 2)") == "1"

    def test_max(self):
        assert calculator("max(3, 1, 2)") == "3"


# ── Error handling ────────────────────────────────────────────────


class TestErrorHandling:
    def test_division_by_zero(self):
        result = calculator("1 / 0")
        assert "Error" in result

    def test_syntax_error(self):
        result = calculator("2 +")
        assert "Error" in result

    def test_empty_expression(self):
        result = calculator("")
        assert "Error" in result


# ── Injection attempts (the whole point of issue #52) ─────────────


class TestInjectionPrevention:
    def test_import_os(self):
        result = calculator("__import__('os').system('echo hacked')")
        assert "Error" in result
        assert "Unknown name" in result or "Unsupported" in result

    def test_builtins_access(self):
        result = calculator("__builtins__")
        assert "Error" in result

    def test_dunder_class(self):
        result = calculator("().__class__.__bases__[0].__subclasses__()")
        assert "Error" in result

    def test_exec(self):
        result = calculator("exec('import os')")
        assert "Error" in result

    def test_eval_nested(self):
        result = calculator("eval('1+1')")
        assert "Error" in result

    def test_open_file(self):
        result = calculator("open('/etc/passwd').read()")
        assert "Error" in result

    def test_string_literal_rejected(self):
        result = calculator("'hello'")
        assert "Error" in result

    def test_list_comprehension(self):
        result = calculator("[x for x in range(10)]")
        assert "Error" in result

    def test_lambda(self):
        result = calculator("(lambda: 1)()")
        assert "Error" in result

    def test_attribute_on_non_math(self):
        result = calculator("(1).__class__")
        assert "Error" in result

    def test_globals(self):
        result = calculator("globals()")
        assert "Error" in result

    def test_breakout_via_format(self):
        result = calculator("'{}'.format.__globals__")
        assert "Error" in result
