import pytest

from miniconf import Config, ConfigError, MissingKeyError, load_layers


def test_plain_values():
    cfg = Config({"name": "app", "port": 8080})
    assert cfg["name"] == "app"
    assert cfg["port"] == 8080
    assert len(cfg) == 2


def test_simple_reference():
    cfg = Config({"host": "localhost", "url": "http://${host}/"})
    assert cfg["url"] == "http://localhost/"


def test_two_references_in_one_value():
    cfg = Config({"host": "db", "port": 5432, "dsn": "${host}:${port}"})
    assert cfg["dsn"] == "db:5432"


def test_chained_reference():
    cfg = Config({"a": "x", "b": "${a}-y", "c": "${b}-z"})
    assert cfg["c"] == "x-y-z"


def test_missing_key_raises():
    cfg = Config({"a": "${nope}"})
    with pytest.raises(MissingKeyError):
        cfg["a"]


def test_missing_key_message():
    cfg = Config({"a": "${nope}"})
    with pytest.raises(MissingKeyError) as excinfo:
        cfg["a"]
    assert str(excinfo.value) == "missing key 'nope' referenced from 'a'"


def test_non_string_passthrough():
    cfg = Config({"n": 3, "flag": True, "nested": {"x": 1}})
    assert cfg["n"] == 3
    assert cfg["flag"] is True
    assert cfg["nested"] == {"x": 1}


def test_get_returns_default_for_unknown_key():
    cfg = Config({"a": "1"})
    assert cfg.get("zzz") is None
    assert cfg.get("zzz", "dflt") == "dflt"


def test_getitem_raises_keyerror_for_unknown_key():
    cfg = Config({"a": "1"})
    with pytest.raises(KeyError):
        cfg["zzz"]


def test_raw_does_not_resolve():
    cfg = Config({"a": "1", "b": "${a}"})
    assert cfg.raw("b") == "${a}"


def test_from_layers_override():
    cfg = Config.from_layers({"a": "1", "b": "2"}, {"b": "3"})
    assert cfg.as_dict() == {"a": "1", "b": "3"}


def test_load_layers_rejects_non_dict():
    with pytest.raises(ConfigError):
        load_layers({"a": 1}, ["not", "a", "dict"])


def test_as_dict_resolves_all():
    cfg = Config({"a": "1", "b": "${a}2"})
    assert cfg.as_dict() == {"a": "1", "b": "12"}


def test_config_rejects_non_dict():
    with pytest.raises(TypeError):
        Config([("a", 1)])