"""Unit tests for the pure helpers behind add-backend / remove-backend / list-backends."""

from __future__ import annotations

from pathlib import Path

import pytest
from pydantic import SecretStr

from neuronetz_gateway.cli.backends import (
    add_or_replace,
    parse,
    redacted_dump,
    remove,
    serialize,
    to_dict,
    update_env_file,
)
from neuronetz_gateway.config import BackendSpec


def _spec(
    name: str, url: str, token: str | None = None, header: str = "Authorization"
) -> BackendSpec:
    return BackendSpec(
        name=name,
        base_url=url,
        auth_token=SecretStr(token) if token else None,
        auth_header=header,
    )


def test_to_dict_omits_default_header_and_scheme() -> None:
    out = to_dict(_spec("a", "http://x"))
    assert out == {"name": "a", "base_url": "http://x"}


def test_to_dict_includes_token_when_present() -> None:
    out = to_dict(_spec("a", "http://x", token="s3cret"))
    assert out["auth_token"] == "s3cret"


def test_to_dict_includes_non_default_header() -> None:
    out = to_dict(_spec("a", "http://x", token="t", header="X-API-Key"))
    assert out["auth_header"] == "X-API-Key"


def test_redacted_dump_hides_token() -> None:
    out = redacted_dump(_spec("a", "http://x", token="s3cret"))
    assert out["auth_token"] == "***"
    # original to_dict still shows it (this fn is the secrets boundary)
    assert to_dict(_spec("a", "http://x", token="s3cret"))["auth_token"] == "s3cret"


def test_serialize_round_trips_via_parse() -> None:
    backends = [
        _spec("embedded", "http://ollama:11434"),
        _spec("public", "https://ollama.neuronetz.ai", token="tok123"),
    ]
    raw = serialize(backends)
    parsed = parse(raw)
    assert [b.name for b in parsed] == ["embedded", "public"]
    assert parsed[0].auth_token is None
    assert parsed[1].auth_token is not None
    assert parsed[1].auth_token.get_secret_value() == "tok123"
    assert parsed[1].base_url == "https://ollama.neuronetz.ai"


def test_parse_empty_returns_empty_list() -> None:
    assert parse("") == []
    assert parse("   ") == []


def test_parse_rejects_non_array() -> None:
    with pytest.raises(ValueError, match="must be a JSON array"):
        parse('{"name":"a","base_url":"http://x"}')


def test_add_appends_when_name_is_new() -> None:
    backends = [_spec("a", "http://a")]
    new = _spec("b", "http://b")
    out = add_or_replace(backends, new)
    assert [b.name for b in out] == ["a", "b"]


def test_add_rejects_duplicate_without_replace() -> None:
    backends = [_spec("a", "http://a")]
    new = _spec("a", "http://a-different")
    with pytest.raises(ValueError, match="already exists"):
        add_or_replace(backends, new)


def test_add_replaces_in_place_when_replace_true() -> None:
    backends = [_spec("a", "http://old"), _spec("b", "http://b")]
    new = _spec("a", "http://new", token="t")
    out = add_or_replace(backends, new, replace=True)
    # Order preserved — "a" stays in slot 0, "b" stays in slot 1.
    assert [b.name for b in out] == ["a", "b"]
    assert out[0].base_url == "http://new"
    assert out[0].auth_token is not None
    assert out[0].auth_token.get_secret_value() == "t"


def test_remove_drops_named_backend() -> None:
    backends = [_spec("a", "http://a"), _spec("b", "http://b")]
    out = remove(backends, "a")
    assert [b.name for b in out] == ["b"]


def test_remove_rejects_unknown_name() -> None:
    backends = [_spec("a", "http://a")]
    with pytest.raises(ValueError, match="no backend named 'ghost'"):
        remove(backends, "ghost")


def test_update_env_file_inserts_when_key_absent(tmp_path: Path) -> None:
    env = tmp_path / ".env"
    env.write_text("FOO=1\nBAR=hello\n", encoding="utf-8")
    update_env_file(env, "[{}]")
    text = env.read_text(encoding="utf-8")
    assert "FOO=1" in text
    assert "BAR=hello" in text
    assert text.rstrip().endswith("OLLAMA_BACKENDS=[{}]")


def test_update_env_file_replaces_existing_line(tmp_path: Path) -> None:
    env = tmp_path / ".env"
    env.write_text(
        "FOO=1\nOLLAMA_BACKENDS=old\nBAR=hello\n", encoding="utf-8"
    )
    update_env_file(env, "new")
    text = env.read_text(encoding="utf-8")
    # exactly one OLLAMA_BACKENDS line, with the new value
    matches = [line for line in text.splitlines() if line.startswith("OLLAMA_BACKENDS=")]
    assert matches == ["OLLAMA_BACKENDS=new"]
    # untouched lines preserved
    assert "FOO=1" in text
    assert "BAR=hello" in text


def test_update_env_file_is_idempotent(tmp_path: Path) -> None:
    env = tmp_path / ".env"
    env.write_text("KEEP=this\n", encoding="utf-8")
    update_env_file(env, "v1")
    update_env_file(env, "v1")  # same value twice
    text = env.read_text(encoding="utf-8")
    matches = [line for line in text.splitlines() if line.startswith("OLLAMA_BACKENDS=")]
    assert matches == ["OLLAMA_BACKENDS=v1"]
    assert "KEEP=this" in text


def test_update_env_file_creates_when_missing(tmp_path: Path) -> None:
    env = tmp_path / "fresh.env"  # doesn't exist yet
    update_env_file(env, "x")
    assert env.read_text(encoding="utf-8").rstrip() == "OLLAMA_BACKENDS=x"