import pytest
from sqlalchemy import text
from sqlalchemy.pool import StaticPool
from sqlmodel import create_engine

from trading_journal import db_migration


def _base_type_of(compiled: str) -> str:
    """Return base type name (e.g. VARCHAR from VARCHAR(13)), upper-cased."""
    return compiled.split("(")[0].strip().upper()


def test_run_migrations_0_to_1(monkeypatch: pytest.MonkeyPatch) -> None:
    # in-memory engine that preserves the same connection (StaticPool)
    engine = create_engine(
        "sqlite:///:memory:",
        connect_args={"check_same_thread": False},
        poolclass=StaticPool,
    )
    monkeypatch.setattr(db_migration, "LATEST_VERSION", 1)
    final_version = db_migration.run_migrations(engine)
    assert final_version == 1

    expected_schema = {
        "users": {
            "id": ("INTEGER", 1, 1),
            "username": ("TEXT", 1, 0),
            "password_hash": ("TEXT", 1, 0),
            "is_active": ("BOOLEAN", 1, 0),
        },
        "cycles": {
            "id": ("INTEGER", 1, 1),
            "user_id": ("INTEGER", 1, 0),
            "friendly_name": ("TEXT", 0, 0),
            "symbol": ("TEXT", 1, 0),
            "underlying_currency": ("TEXT", 1, 0),
            "status": ("TEXT", 1, 0),
            "funding_source": ("TEXT", 1, 0),
            "capital_exposure_cents": ("INTEGER", 1, 0),
            "loan_amount_cents": ("INTEGER", 0, 0),
            "loan_interest_rate_bps": ("INTEGER", 0, 0),
            "start_date": ("DATE", 1, 0),
            "end_date": ("DATE", 0, 0),
        },
        "trades": {
            "id": ("INTEGER", 1, 1),
            "user_id": ("INTEGER", 1, 0),
            "friendly_name": ("TEXT", 0, 0),
            "symbol": ("TEXT", 1, 0),
            "underlying_currency": ("TEXT", 1, 0),
            "trade_type": ("TEXT", 1, 0),
            "trade_strategy": ("TEXT", 1, 0),
            "trade_time_utc": ("DATETIME", 1, 0),
            "expiry_date": ("DATE", 0, 0),
            "strike_price_cents": ("INTEGER", 0, 0),
            "quantity": ("INTEGER", 1, 0),
            "price_cents": ("INTEGER", 1, 0),
            "gross_cash_flow_cents": ("INTEGER", 1, 0),
            "commission_cents": ("INTEGER", 1, 0),
            "net_cash_flow_cents": ("INTEGER", 1, 0),
            "cycle_id": ("INTEGER", 0, 0),
        },
    }

    expected_fks = {
        "trades": [
            {"table": "cycles", "from": "cycle_id", "to": "id"},
            {"table": "users", "from": "user_id", "to": "id"},
        ],
        "cycles": [
            {"table": "users", "from": "user_id", "to": "id"},
        ],
    }

    with engine.connect() as conn:
        # check tables exist
        rows = conn.execute(
            text("SELECT name FROM sqlite_master WHERE type='table'")
        ).fetchall()
        found_tables = {r[0] for r in rows}
        assert set(expected_schema.keys()).issubset(found_tables), (
            f"missing tables: {set(expected_schema.keys()) - found_tables}"
        )

        # check user_version
        uv = conn.execute(text("PRAGMA user_version")).fetchone()
        assert uv is not None
        assert int(uv[0]) == 1

        # validate each table columns
        for tbl_name, cols in expected_schema.items():
            info_rows = conn.execute(text(f"PRAGMA table_info({tbl_name})")).fetchall()
            # map: name -> (type, notnull, pk)
            actual = {
                r[1]: ((r[2] or "").upper(), int(r[3]), int(r[5])) for r in info_rows
            }
            for colname, (exp_type, exp_notnull, exp_pk) in cols.items():
                assert colname in actual, f"{tbl_name}: missing column {colname}"
                act_type, act_notnull, act_pk = actual[colname]
                # compare base type (e.g. VARCHAR(13) -> VARCHAR)
                if act_type:
                    act_base = _base_type_of(act_type)
                else:
                    act_base = ""
                assert exp_type in act_base or act_base in exp_type, (
                    f"type mismatch {tbl_name}.{colname}: expected {exp_type}, got {act_base}"
                )
                assert act_notnull == exp_notnull, (
                    f"notnull mismatch {tbl_name}.{colname}: expected {exp_notnull}, got {act_notnull}"
                )
                assert act_pk == exp_pk, (
                    f"pk mismatch {tbl_name}.{colname}: expected {exp_pk}, got {act_pk}"
                )
        for tbl_name, fks in expected_fks.items():
            fk_rows = conn.execute(
                text(f"PRAGMA foreign_key_list('{tbl_name}')")
            ).fetchall()
            # fk_rows columns: (id, seq, table, from, to, on_update, on_delete, match)
            actual_fk_list = [
                {"table": r[2], "from": r[3], "to": r[4]} for r in fk_rows
            ]
            for efk in fks:
                assert efk in actual_fk_list, f"missing FK on {tbl_name}: {efk}"