import pytest
from student import Student  # assumes Student class is in student.py


# ---------- FIXTURES ----------
@pytest.fixture
def valid_student():
    """Fixture for a valid student object"""
    return Student("Alice", 123456, 4.0)

def test_create_valid_student(valid_student):
    assert valid_student.get_name() == "Alice"
    assert valid_student.get_gNumber() == 123456
    assert valid_student.get_gpa() == 4.0


def test_update_name(valid_student):
    valid_student.set_name("Bob")
    assert valid_student.get_name() == "Bob"


def test_update_gNumber(valid_student):
    valid_student.set_gNumber(654321)
    assert valid_student.get_gNumber() == 654321


def test_update_gpa(valid_student):
    valid_student.set_gpa(5.5)
    assert valid_student.get_gpa() == 5.5


# ---------- NAME VALIDATION ----------
@pytest.mark.parametrize("invalid_name", [
    "",                          # empty string
    "A" * 256,                   # too long
    "Alice123",                  # contains digits
    "Alice!",                    # contains special character
    123,                         # not a string
])
def test_invalid_name_raises(invalid_name):
    with pytest.raises((ValueError, TypeError)):
        Student(invalid_name, 123456, 3.0)


# ---------- gNumber VALIDATION ----------
@pytest.mark.parametrize("invalid_gNumber", [
    99999,     # too small
    1000000,   # too large
    "123456",  # not an int
    12.34,     # float
])
def test_invalid_gNumber_raises(invalid_gNumber):
    with pytest.raises((ValueError, TypeError)):
        Student("Charlie", invalid_gNumber, 3.5)


def test_boundary_gNumber_valid():
    s1 = Student("David", 100000, 2.0)
    s2 = Student("Eve", 999999, 3.0)
    assert s1.get_gNumber() == 100000
    assert s2.get_gNumber() == 999999


# ---------- GPA VALIDATION ----------
@pytest.mark.parametrize("invalid_gpa", [
    -0.1,      # below range
    6.1,       # above range
    "4.0",     # string instead of number
    None,      # NoneType
])
def test_invalid_gpa_raises(invalid_gpa):
    with pytest.raises((ValueError, TypeError)):
        Student("Frank", 222222, invalid_gpa)


def test_boundary_gpa_valid():
    s1 = Student("Grace", 333333, 0.0)
    s2 = Student("Heidi", 444444, 6.0)
    assert s1.get_gpa() == 0.0
    assert s2.get_gpa() == 6.0


# ---------- STRING REPRESENTATION ----------
def test_str_representation(valid_student):
    s = str(valid_student)
    assert "Alice" in s
    assert "123456" in s
    assert "4.00" in s