"""Tests para pivot_table_duckdb."""

import os
import sys

import duckdb

# Permitir importar funciones del registry (from infra import ..., from datascience import ...).
sys.path.insert(0, os.path.join(os.path.dirname(__file__), "..", ".."))
sys.path.insert(0, os.path.join(os.path.dirname(__file__), "..", "..", "functions"))

from datascience.pivot_table_duckdb import pivot_table_duckdb


def _make_db(tmp_name: str) -> str:
    """Crea una DuckDB con dos categoricas (a, b) y un valor numerico conocido.

    Filas:
        a='x', b='y', val=10
        a='x', b='y', val=20   -> mean(x,y) = 15, count(x,y) = 2
        a='x', b='z', val=5    -> mean(x,z) = 5
        a='w', b='y', val=100  -> mean(w,y) = 100
    Observaciones por a: x=3, w=1.  Por b: y=3, z=1.
    La combinacion (w, z) no existe -> celda None.
    """
    db = os.path.join("/tmp", tmp_name)
    if os.path.exists(db):
        os.remove(db)
    con = duckdb.connect(db)
    con.execute("CREATE TABLE t (a VARCHAR, b VARCHAR, val DOUBLE)")
    con.execute(
        "INSERT INTO t VALUES "
        "('x','y',10),('x','y',20),('x','z',5),('w','y',100)"
    )
    con.close()
    return db


def test_pivot_mean_labels_y_celda_conocida():
    db = _make_db("pivot_test_mean.duckdb")
    res = pivot_table_duckdb(db, "t", index="a", columns="b", value="val", agg="mean")
    assert res["status"] == "ok", res
    # Filas ordenadas por observaciones desc: x (3) antes que w (1).
    assert res["row_labels"] == ["x", "w"], res["row_labels"]
    # Columnas ordenadas por observaciones desc: y (3) antes que z (1).
    assert res["col_labels"] == ["y", "z"], res["col_labels"]
    # matrix[0][0] = mean(a='x', b='y') = (10 + 20) / 2 = 15.
    assert abs(res["matrix"][0][0] - 15.0) < 1e-9, res["matrix"]
    # matrix[0][1] = mean(a='x', b='z') = 5.
    assert abs(res["matrix"][0][1] - 5.0) < 1e-9, res["matrix"]
    # matrix[1][0] = mean(a='w', b='y') = 100.
    assert abs(res["matrix"][1][0] - 100.0) < 1e-9, res["matrix"]
    # (w, z) no existe -> None.
    assert res["matrix"][1][1] is None, res["matrix"]
    # Sin truncado con los defaults (top_rows=10, top_cols=8).
    assert res["truncated_rows"] is False
    assert res["truncated_cols"] is False
    # La matriz es rectangular consistente con las etiquetas.
    assert len(res["matrix"]) == len(res["row_labels"])
    for fila in res["matrix"]:
        assert len(fila) == len(res["col_labels"])


def test_pivot_trunca_a_top_rows_y_top_cols():
    db = _make_db("pivot_test_trunc.duckdb")
    res = pivot_table_duckdb(
        db, "t", index="a", columns="b", value="val", agg="mean",
        top_rows=1, top_cols=1,
    )
    assert res["status"] == "ok", res
    # Solo la fila/columna mas frecuente sobrevive.
    assert res["row_labels"] == ["x"], res["row_labels"]
    assert res["col_labels"] == ["y"], res["col_labels"]
    assert res["matrix"] == [[15.0]], res["matrix"]
    # Habia mas de 1 fila y mas de 1 columna -> truncado en ambos ejes.
    assert res["truncated_rows"] is True
    assert res["truncated_cols"] is True


def test_pivot_count_no_necesita_value_real():
    db = _make_db("pivot_test_count.duckdb")
    # value apunta a una columna real pero count(*) la ignora; tambien valdria un
    # nombre cualquiera. Verificamos que count funciona igualmente.
    res = pivot_table_duckdb(
        db, "t", index="a", columns="b", value="val", agg="count"
    )
    assert res["status"] == "ok", res
    assert res["row_labels"] == ["x", "w"]
    assert res["col_labels"] == ["y", "z"]
    # count(a='x', b='y') = 2 observaciones.
    assert res["matrix"][0][0] == 2, res["matrix"]
    # count(a='x', b='z') = 1.
    assert res["matrix"][0][1] == 1, res["matrix"]
    # count(a='w', b='y') = 1.
    assert res["matrix"][1][0] == 1, res["matrix"]
    # (w, z) no existe -> None.
    assert res["matrix"][1][1] is None, res["matrix"]


def test_pivot_db_inexistente_devuelve_error_sin_lanzar():
    res = pivot_table_duckdb(
        "/nonexistent/path/does_not_exist.duckdb",
        "t", index="a", columns="b", value="val", agg="mean",
    )
    assert res["status"] == "error", res
    assert isinstance(res["error"], str)


def test_pivot_agg_invalido_devuelve_error():
    db = _make_db("pivot_test_badagg.duckdb")
    res = pivot_table_duckdb(
        db, "t", index="a", columns="b", value="val", agg="stddev"
    )
    assert res["status"] == "error", res
    assert "invalid agg" in res["error"]