"""Check reference SQL against independently generated Python answers."""

import json

import pytest

from sql_investigation.tasks import TASK_IDS, build_task


def _assert_same_rows(actual, expected):
    assert len(actual) == len(expected)
    for actual_row, expected_row in zip(sorted(actual), sorted(expected)):
        assert len(actual_row) == len(expected_row)
        for actual_value, expected_value in zip(actual_row, expected_row):
            if isinstance(expected_value, float):
                assert actual_value == pytest.approx(expected_value, abs=1e-7)
            else:
                assert actual_value == expected_value


@pytest.mark.parametrize("task_id", TASK_IDS)
@pytest.mark.parametrize("seed", [*range(10), 737])
def test_oracle_matches_independent_python_answer(task_id, seed):
    task = build_task(task_id, seed)
    try:
        result = task.connection.execute(task.oracle_sql).fetchall()
        _assert_same_rows(result, task.expected_rows)
        assert 1 <= len(result) <= 20
        assert all(isinstance(row, list) for row in task.expected_rows)
        json.dumps(task.expected_rows, allow_nan=False)
        tables = task.connection.execute(
            "SELECT name FROM sqlite_master WHERE type = 'table'"
        ).fetchall()
        assert tables
        assert not any(
            "answer" in name or "oracle" in name or "expected" in name for (name,) in tables
        )
        total_rows = sum(
            task.connection.execute(f'SELECT COUNT(*) FROM "{name}"').fetchone()[0]
            for (name,) in tables
        )
        assert 30 <= total_rows <= 200
    finally:
        task.connection.close()


@pytest.mark.parametrize("task_id", TASK_IDS)
def test_tasks_are_reproducible_and_seed_sensitive(task_id):
    first = build_task(task_id, 42)
    same = build_task(task_id, 42)
    other = build_task(task_id, 43)
    try:
        assert first.instruction == same.instruction
        assert first.schema == same.schema
        assert first.expected_rows == same.expected_rows
        assert list(first.connection.iterdump()) == list(same.connection.iterdump())
        assert first.expected_rows != other.expected_rows
        assert list(first.connection.iterdump()) != list(other.connection.iterdump())
    finally:
        first.connection.close()
        same.connection.close()
        other.connection.close()


def test_unknown_task_is_rejected():
    with pytest.raises(ValueError, match="Unknown task_id"):
        build_task("not_a_task", 0)