import datetime
import dates
from dates import Precision

def test_easter_known_years():
    # Anonymous Gregorian algorithm — verified against published tables
    assert dates.easter(2024) == datetime.date(2024, 3, 31)
    assert dates.easter(2000) == datetime.date(2000, 4, 23)
    assert dates.easter(1922) == datetime.date(1922, 4, 16)
    assert dates.easter(1888) == datetime.date(1888, 4, 1)

def test_resolve_feast_movable():
    assert dates.resolve_feast_or_season("Pfingsten", 1922) == ("1922-06-04", Precision.DAY)
    assert dates.resolve_feast_or_season("Ostern", 2024) == ("2024-03-31", Precision.DAY)
    assert dates.resolve_feast_or_season("Pfingstmontag", 1922) == ("1922-06-05", Precision.DAY)

def test_resolve_feast_fixed():
    assert dates.resolve_feast_or_season("Weihnachten", 1900) == ("1900-12-25", Precision.DAY)
    assert dates.resolve_feast_or_season("Neujahr", 1910) == ("1910-01-01", Precision.DAY)

def test_resolve_season():
    assert dates.resolve_feast_or_season("Herbst", 1913) == ("1913-10-01", Precision.SEASON)
    assert dates.resolve_feast_or_season("Sommer", 1910) == ("1910-07-01", Precision.SEASON)

def test_resolve_unknown_token_returns_none():
    assert dates.resolve_feast_or_season("Freitag", 1919) is None

def test_expand_year():
    assert dates.expand_year("1888") == 1888
    assert dates.expand_year("889") == 1889      # 3-digit -> 1DDD
    assert dates.expand_year("923") == 1923
    assert dates.expand_year("08") == 1908       # 00..57 -> 19xx
    assert dates.expand_year("17") == 1917
    assert dates.expand_year("57") == 1957
    assert dates.expand_year("73") == 1873       # 73..99 -> 18xx
    assert dates.expand_year("99") == 1899
    assert dates.expand_year("65") is None       # 58..72 ambiguous
    assert dates.expand_year("x") is None

def test_parse_iso_and_empty():
    assert dates.parse_date("1910-04-23") == dates.ParsedDate("1910-04-23", Precision.DAY, "1910-04-23")
    assert dates.parse_date("") == dates.ParsedDate(None, Precision.UNKNOWN, "")
    assert dates.parse_date("?") == dates.ParsedDate(None, Precision.UNKNOWN, "?")

def test_parse_numeric_forms():
    assert dates.parse_date("15.2.1888").iso == "1888-02-15"
    assert dates.parse_date("13.5.09").iso == "1909-05-13"
    assert dates.parse_date("17/6. 1916").iso == "1916-06-17"
    assert dates.parse_date("11.10.08").iso == "1908-10-11"
    assert dates.parse_date("30.1.889").iso == "1889-01-30"
    assert dates.parse_date("15.2.1888").precision == Precision.DAY

def test_parse_numeric_unparseable():
    assert dates.parse_date("8.9.").precision == Precision.UNKNOWN     # no year
    assert dates.parse_date("13.5.65").precision == Precision.UNKNOWN  # ambiguous 2-digit year

def test_parse_approx_marker_upgrades_precision():
    r = dates.parse_date("17.Nov (?) 1887")  # month-name matcher now active; (?) marks approx
    assert r.raw == "17.Nov (?) 1887"
    assert r.precision == Precision.APPROX  # month-name matcher parses date; (?) upgrades to APPROX

def test_parse_leading_qualifier_is_approx():
    r = dates.parse_date("nach 1.5.1900")  # qualifier stripped, numeric date salvaged, precision APPROX
    assert r.iso == "1900-05-01"
    assert r.precision == Precision.APPROX

def test_parse_roman_months():
    assert dates.parse_date("22.III.18").iso == "1918-03-22"
    assert dates.parse_date("19.XII.1954").iso == "1954-12-19"
    assert dates.parse_date("1.III.27").iso == "1927-03-01"
    assert dates.parse_date("22.III.18").precision == Precision.DAY

def test_parse_monthname_day_first():
    assert dates.parse_date("6.März 1888").iso == "1888-03-06"
    assert dates.parse_date("29.Sept.1891").iso == "1891-09-29"
    assert dates.parse_date("10.Oct.95").iso == "1895-10-10"
    assert dates.parse_date("9.December1889").iso == "1889-12-09"
    assert dates.parse_date("18.Dez.1916").iso == "1916-12-18"
    assert dates.parse_date("4Dezember 1936").iso == "1936-12-04"
    assert dates.parse_date("25 August 1968").iso == "1968-08-25"

def test_parse_month_year_year_only():
    assert dates.parse_date("Mai 1895") == dates.ParsedDate("1895-05-01", Precision.MONTH, "Mai 1895")
    assert dates.parse_date("October 1903").iso == "1903-10-01"
    assert dates.parse_date("1905") == dates.ParsedDate("1905-01-01", Precision.YEAR, "1905")

def test_parse_feast_and_season_via_parse_date():
    assert dates.parse_date("Pfingsten 1922") == dates.ParsedDate("1922-06-04", Precision.DAY, "Pfingsten 1922")
    assert dates.parse_date("Herbst 1913") == dates.ParsedDate("1913-10-01", Precision.SEASON, "Herbst 1913")
    assert dates.parse_date("Pfingstsonntag 1915").precision == Precision.DAY

def test_parse_ranges():
    assert dates.parse_date("8.1.1916 - 15.3.1916") == dates.ParsedDate("1916-01-08", Precision.RANGE, "8.1.1916 - 15.3.1916")
    assert dates.parse_date("1881/82") == dates.ParsedDate("1881-01-01", Precision.RANGE, "1881/82")
    assert dates.parse_date("1945/46?").iso == "1945-01-01"  # '?' stripped -> RANGE, then APPROX
    assert dates.parse_date("1945/46?").precision == Precision.APPROX

def test_parse_approx_full():
    r = dates.parse_date("17.Nov (?) 1887")
    assert r.iso == "1887-11-17"
    assert r.precision == Precision.APPROX

def test_parse_english_month_first_now_works():
    assert dates.parse_date("April 12. 1922").iso == "1922-04-12"
    assert dates.parse_date("Mai 1895").iso == "1895-05-01"  # not shadowed by month-first matcher

def test_parse_unparseable_examples():
    assert dates.parse_date("Freitag 1919").precision == Precision.UNKNOWN

def test_parse_invalid_calendar_date_is_unknown():
    # try/except ValueError in the matchers must route impossible dates to UNKNOWN (-> review),
    # never silently clamp. This is the most likely real-data bug class at 7,600 rows.
    assert dates.parse_date("30.2.1888").precision == Precision.UNKNOWN
    assert dates.parse_date("31.4.1916").precision == Precision.UNKNOWN

def test_parse_intra_month_day_range():
    # "7./8. Sept.1923" -> start day, RANGE. Must NOT be confused with slash-date "17/6. 1916".
    assert dates.parse_date("7./8. Sept.1923") == dates.ParsedDate("1923-09-07", Precision.RANGE, "7./8. Sept.1923")
    assert dates.parse_date("17/6. 1916") == dates.ParsedDate("1916-06-17", Precision.DAY, "17/6. 1916")

def test_parse_trailing_note_stripped_but_raw_preserved():
    r = dates.parse_date("17.Nov 1887, 2. Brief")  # REQ-DATE-04
    assert r.iso == "1887-11-17"
    assert "2. Brief" in r.raw   # original string preserved verbatim

def test_parse_date_override_wins():
    ovr = {"13.5.65": ("1965-05-13", "DAY")}
    r = dates.parse_date("13.5.65", ovr)  # ambiguous without override
    assert r == dates.ParsedDate("1965-05-13", Precision.DAY, "13.5.65")