"""The `sql` connector (ingest-spec §4, §8).

sqlite via connection_ref env-var resolution (the ref names the variable;
its value is the database path), read-only open, single statement,
streaming max_rows cap, typed errors for every sqlite failure.
"""

from __future__ import annotations

import sqlite3
from pathlib import Path

import pytest

from llm_ingestion_okf.connectors import read_sql
from llm_ingestion_okf.errors import IngestError, SourceError

REF = "OKF_TEST_DB"


@pytest.fixture
def db_path(tmp_path: Path, monkeypatch: pytest.MonkeyPatch) -> Path:
    path = tmp_path / "fixture.db"
    with sqlite3.connect(path) as conn:
        conn.execute("CREATE TABLE t (id INTEGER, name TEXT, score REAL, note TEXT)")
        conn.executemany(
            "INSERT INTO t VALUES (?, ?, ?, ?)",
            [(1, "alpha", 1.5, None), (2, "beta", 0.1, "x|y")],
        )
    monkeypatch.setenv(REF, str(path))
    return path


# --- happy path: §5 text form, source order ---


def test_reads_header_and_rows_as_text(db_path: Path) -> None:
    header, rows = read_sql(REF, "SELECT id, name, score, note FROM t ORDER BY id", max_rows=10)
    assert header == ["id", "name", "score", "note"]
    # NULL -> empty string; int plain decimal; float shortest round-trip; text verbatim.
    assert rows == [["1", "alpha", "1.5", ""], ["2", "beta", "0.1", "x|y"]]


# --- env-var resolution (credentials never in the manifest, §4) ---


def test_unset_connection_ref_rejected(monkeypatch: pytest.MonkeyPatch) -> None:
    monkeypatch.delenv(REF, raising=False)
    with pytest.raises(SourceError):
        read_sql(REF, "SELECT 1", max_rows=10)


def test_empty_connection_ref_rejected(monkeypatch: pytest.MonkeyPatch) -> None:
    monkeypatch.setenv(REF, "")
    with pytest.raises(SourceError):
        read_sql(REF, "SELECT 1", max_rows=10)


def test_missing_database_file_rejected(tmp_path: Path, monkeypatch: pytest.MonkeyPatch) -> None:
    monkeypatch.setenv(REF, str(tmp_path / "nope.db"))
    with pytest.raises(SourceError):
        read_sql(REF, "SELECT 1", max_rows=10)


# --- read-only, single statement, typed sqlite errors ---


def test_write_statement_fails_at_the_database(db_path: Path) -> None:
    """Read-only is enforced by the connection mode, not string parsing."""
    with pytest.raises(SourceError):
        read_sql(REF, "DELETE FROM t", max_rows=10)


def test_multiple_statements_rejected(db_path: Path) -> None:
    with pytest.raises(SourceError):
        read_sql(REF, "SELECT 1; SELECT 2", max_rows=10)


def test_syntax_error_wrapped_in_typed_error(db_path: Path) -> None:
    with pytest.raises(SourceError):
        read_sql(REF, "SELEC nonsense", max_rows=10)


def test_blob_cell_fails_typed(db_path: Path, tmp_path: Path) -> None:
    """Never silent coercion (§5): a BLOB cell is a typed IngestError."""
    with sqlite3.connect(tmp_path / "fixture.db") as conn:
        conn.execute("INSERT INTO t VALUES (3, 'blob', 0.0, x'DEADBEEF')")
    with pytest.raises(IngestError):
        read_sql(REF, "SELECT note FROM t WHERE id = 3", max_rows=10)


# --- max_rows cap (§8): error, never silent truncation ---


def test_row_count_at_cap_is_allowed(db_path: Path) -> None:
    _, rows = read_sql(REF, "SELECT id FROM t ORDER BY id", max_rows=2)
    assert len(rows) == 2


def test_exceeding_cap_is_an_error(db_path: Path) -> None:
    with pytest.raises(SourceError):
        read_sql(REF, "SELECT id FROM t ORDER BY id", max_rows=1)