import pytest

import gen_rack


def item(**kw):
    base = {"hostname": "x", "kind": "server", "status": "in-use", "rack": "rack01"}
    base.update(kw)
    return base


def test_validate_accepts_valid_placement():
    gen_rack.validate_item(item(rack_u=12, u_height=2, rack_face="front"))


def test_validate_rejects_u_overflow():
    with pytest.raises(gen_rack.SchemaError):
        gen_rack.validate_item(item(rack_u=47, u_height=3, rack_face="front"))


def test_validate_rejects_u_below_one():
    with pytest.raises(gen_rack.SchemaError):
        gen_rack.validate_item(item(rack_u=0, u_height=1, rack_face="front"))


def test_validate_rejects_bad_face():
    with pytest.raises(gen_rack.SchemaError):
        gen_rack.validate_item(item(rack_u=1, u_height=1, rack_face="sideways"))


def test_validate_rejects_zero_u_with_units():
    with pytest.raises(gen_rack.SchemaError):
        gen_rack.validate_item(item(rack_face="left", rack_u=1, u_height=1))


def test_validate_accepts_zero_u_rail():
    gen_rack.validate_item(item(rack_face="left"))


def test_validate_rejects_missing_units_on_faced_item():
    with pytest.raises(gen_rack.SchemaError):
        gen_rack.validate_item(item(rack_face="front"))


def test_overlaps_detects_same_face_overlap():
    items = [
        item(hostname="a", rack_u=1, u_height=2, rack_face="front"),
        item(hostname="b", rack_u=2, u_height=1, rack_face="front"),
    ]
    with pytest.raises(gen_rack.SchemaError):
        gen_rack.check_overlaps(items)


def test_overlaps_allows_same_u_different_face():
    items = [
        item(hostname="a", rack_u=5, u_height=1, rack_face="front"),
        item(hostname="b", rack_u=5, u_height=1, rack_face="rear"),
    ]
    gen_rack.check_overlaps(items)  # no raise


def test_overlaps_both_face_conflicts_with_front():
    items = [
        item(hostname="a", rack_u=5, u_height=1, rack_face="both"),
        item(hostname="b", rack_u=5, u_height=1, rack_face="front"),
    ]
    with pytest.raises(gen_rack.SchemaError):
        gen_rack.check_overlaps(items)


def test_overlaps_ignores_zero_u_rails():
    items = [
        item(hostname="p1", rack_face="left"),
        item(hostname="p2", rack_face="left"),
    ]
    gen_rack.check_overlaps(items)  # no raise