"""Benchmark fixtures — long-lived connections + populated test tables.

The end-to-end benchmark suite needs:
* A persistent connection (creating one per benchmark inflates the cost
  by the login handshake, ~5-15ms — distorts micro-second measurements).
* A pre-populated test table so SELECT/UPDATE benchmarks have rows to
  iterate.

Both fixtures are session-scoped so the table is created exactly once
even when the same benchmark is iterated over many rounds.
"""

from __future__ import annotations

import contextlib
from collections.abc import Iterator

import pytest

import informix_db
from tests.conftest import ConnParams

BENCH_TABLE_ROWS = 1000  # rows in the populated benchmark table


@pytest.fixture(scope="session")
def bench_conn(conn_params: ConnParams) -> Iterator[informix_db.Connection]:
    """One long-lived autocommit connection for the entire bench session."""
    conn = informix_db.connect(
        host=conn_params.host,
        port=conn_params.port,
        user=conn_params.user,
        password=conn_params.password,
        database=conn_params.database,
        server=conn_params.server,
        autocommit=True,
    )
    try:
        yield conn
    finally:
        conn.close()


@pytest.fixture(scope="session")
def bench_table(bench_conn: informix_db.Connection) -> Iterator[str]:
    """Create + populate a 1k-row table for SELECT/UPDATE benchmarks.

    Yields the table name. The table is dropped at session teardown.
    Schema covers the common type mix: INT id, VARCHAR name,
    INT (counter), FLOAT (value), DATE (created).
    """
    table = "p21_bench"
    cur = bench_conn.cursor()
    with contextlib.suppress(informix_db.Error):
        cur.execute(f"DROP TABLE {table}")
    cur.execute(
        f"CREATE TABLE {table} ("
        " id INT, name VARCHAR(64), counter INT,"
        " value FLOAT, created DATE)"
    )
    # Populate via executemany so setup is fast.
    rows = [
        (
            i,
            f"row_{i:04d}",
            i * 7,
            float(i) * 1.5,
            None,  # DATE NULL — keeps fixture small
        )
        for i in range(BENCH_TABLE_ROWS)
    ]
    cur.executemany(
        f"INSERT INTO {table} VALUES (?, ?, ?, ?, ?)",
        rows,
    )
    try:
        yield table
    finally:
        with contextlib.suppress(informix_db.Error):
            cur.execute(f"DROP TABLE {table}")