import sqlite3
from sfm.database import SeismoDb

_SHAPE_COLS = {"shape_crest_factor", "shape_near_peak_count",
               "shape_sample_count", "shape_axis"}

def _cols(db):
    with sqlite3.connect(db.db_path) as c:
        return {r[1] for r in c.execute("PRAGMA table_info(events)")}

def test_fresh_db_has_shape_columns(tmp_path):
    db = SeismoDb(tmp_path / "s.db")
    assert _SHAPE_COLS <= _cols(db)

def test_existing_db_migrates_shape_columns(tmp_path):
    p = tmp_path / "s.db"
    db = SeismoDb(p)
    with sqlite3.connect(p) as c:      # simulate an older DB missing the columns
        for col in _SHAPE_COLS:
            c.execute(f"ALTER TABLE events DROP COLUMN {col}")
    # sanity: dropped. Read via the already-constructed `db` (a raw PRAGMA
    # read against db.db_path) rather than a fresh SeismoDb(p) — the latter
    # would immediately re-trigger _migrate's self-healing ADD COLUMN loop
    # and mask the gap we're trying to confirm.
    assert not (_SHAPE_COLS <= _cols(db))
    SeismoDb(p)                        # re-open triggers _migrate
    assert _SHAPE_COLS <= _cols(SeismoDb(p))