import sys
from pathlib import Path
sys.path.insert(0, str(Path(__file__).parent.parent))

import persons_tree


def test_parse_year_iso_string():
    assert persons_tree._parse_year("1920-09-20") == 1920


def test_parse_year_excel_serial_birth():
    # 7568 days from 1899-12-30 = 1920-09-19 or -20 depending on leap counting
    assert persons_tree._parse_year("7568") == 1920


def test_parse_year_excel_serial_death():
    # 36222 days from 1899-12-30 ≈ 1999
    assert persons_tree._parse_year("36222") == 1999


def test_parse_year_excel_serial_small():
    # 177 days from 1899-12-30 = 1900-06-25
    assert persons_tree._parse_year("177") == 1900


def test_parse_year_german_date_string():
    assert persons_tree._parse_year("30.8.1862") == 1862


def test_parse_year_year_only():
    assert persons_tree._parse_year("1930") == 1930


def test_parse_year_free_text():
    assert persons_tree._parse_year("August 1941") == 1941


def test_parse_year_none():
    assert persons_tree._parse_year(None) is None


def test_parse_year_empty():
    assert persons_tree._parse_year("") is None


def test_parse_year_unresolvable_truncated():
    # "2.9.196" has no valid 4-digit year — returns None
    assert persons_tree._parse_year("2.9.196") is None


def test_parse_year_typo_year():
    # "4.3.1023" — year 1023 outside 1700-2100 guard — returns None
    assert persons_tree._parse_year("4.3.1023") is None


def test_parse_year_bare_out_of_range_year_is_none():
    # "1023" is a plausible typo for "1923" but is NOT an Excel serial.
    # parse_date("1023") parses it as year 1023 (out of 1700-2100 guard).
    # The serial branch must NOT re-interpret it as a serial.
    assert persons_tree._parse_year("1023") is None


def test_parse_generation_space():
    assert persons_tree._parse_generation("G 3") == 3


def test_parse_generation_no_space():
    assert persons_tree._parse_generation("G3") == 3


def test_parse_generation_extra_spaces():
    assert persons_tree._parse_generation("G  0") == 0


def test_parse_generation_trailing_garbage():
    assert persons_tree._parse_generation("G 2         de Gruyter") == 2


def test_parse_generation_empty():
    assert persons_tree._parse_generation("") is None


def test_parse_generation_none():
    assert persons_tree._parse_generation(None) is None