import unicodedata

from .. import seq_editops, editops


def test_trivial():
    assert seq_editops('abc', 'abc') == []
    assert seq_editops('', '') == []


def test_insert():
    assert seq_editops('bc', 'abc') == [('insert', 0, 0)]
    assert seq_editops('ac', 'abc') == [('insert', 1, 1)]
    assert seq_editops('ab', 'abc') == [('insert', 2, 2)]
    assert seq_editops('', 'a') == [('insert', 0, 0)]


def test_multiple():
    assert seq_editops('bcd', 'abce') == [('insert', 0, 0), ('replace', 2, 3)]


def test_delete():
    assert seq_editops('abcdef', 'cdef') == [('delete', 0, 0), ('delete', 1, 0)]
    assert seq_editops('Xabcdef', 'Xcdef') == [('delete', 1, 1), ('delete', 2, 1)]
    assert seq_editops('abcdefg', 'acdefX') == [('delete', 1, 1), ('replace', 6, 5)]
    assert seq_editops('abcde', 'aabcd') == [('insert', 1, 1), ('delete', 4, 5)]
    assert seq_editops('Foo', '') == [('delete', 0, 0), ('delete', 1, 0), ('delete', 2, 0)]
    assert seq_editops('Foolish', 'Foo') == [('delete', 3, 3), ('delete', 4, 3), ('delete', 5, 3), ('delete', 6, 3)]


def test_ambiguous():
    assert seq_editops('bcd', 'abcef') == [('insert', 0, 0), ('replace', 2, 3), ('insert', 3, 4)]


def test_editops():
    """Test editops() in cases where dealing with grapheme clusters matters"""

    # In these cases, one of the words has a composed form, the other one does not.
    assert editops('Schlyñ', 'Schlym̃') == [('replace', 5, 5)]
    assert editops('oͤde', 'öde') == [('replace', 0, 0)]


def test_editops_canonically_equivalent():
    left = unicodedata.lookup('LATIN SMALL LETTER N') + unicodedata.lookup('COMBINING TILDE')
    right = unicodedata.lookup('LATIN SMALL LETTER N WITH TILDE')
    assert left != right
    assert unicodedata.normalize('NFC', left) == unicodedata.normalize('NFC', right)
    assert editops(left, right) == []