import pytest
from matrixmania.compute import matmul, transpose

# --- Tests für Transponieren ---
def test_transpose_regular():
    # Testet eine normale 2x3 Matrix
    matrix = [
        [1, 2, 3],
        [4, 5, 6]
    ]
    expected = [
        [1, 4],
        [2, 5],
        [3, 6]
    ]
    assert transpose(matrix) == expected

def test_transpose_empty():
    # Testet, ob der ValueError bei leerer Matrix kommt
    with pytest.raises(ValueError):
        transpose([])

# --- Tests für Matrixmultiplikation (matmul) ---
def test_matmul_simple():
    # Einfache Multiplikation 2x2 * 2x1
    A = [[1, 2], [3, 4]]
    B = [[5], [6]]
    # Rechnung:
    # 1*5 + 2*6 = 5 + 12 = 17
    # 3*5 + 4*6 = 15 + 24 = 39
    expected = [[17], [39]]
    assert matmul(A, B) == expected

def test_matmul_invalid_dimensions():
    # Testet, ob Fehler geworfen wird, wenn Dimensionen nicht passen
    A = [[1, 2]] # 1x2
    B = [[1, 2]] # 1x2 -> Spalten A (2) != Zeilen B (1)
    with pytest.raises(ValueError):
        matmul(A, B)