"""Dostawcy LLM (LOG-31) — bez wołania jakiegokolwiek prawdziwego modelu.

Transport podstawiamy przez httpx.MockTransport, więc testy są szybkie,
deterministyczne i nic nie wychodzi na zewnątrz.
"""
import httpx
import pytest

from app.llm import factory
from app.llm.base import Completion, LLMError
from app.llm.providers import AnthropicProvider, ChatCompletionsProvider


def _mock_client(handler):
    """Podmienia httpx.Client na wersję z transportem testowym."""
    class _C(httpx.Client):
        def __init__(self, *a, **kw):
            kw["transport"] = httpx.MockTransport(handler)
            super().__init__(*a, **kw)
    return _C


@pytest.fixture
def chat_ok(monkeypatch):
    def handler(request):
        assert request.url.path.endswith("/chat/completions")
        return httpx.Response(200, json={
            "model": "test-model",
            "choices": [{"message": {"content": "Horoskop testowy."}}],
            "usage": {"prompt_tokens": 100, "completion_tokens": 50},
        })
    monkeypatch.setattr(httpx, "Client", _mock_client(handler))


# ------------------------------------------------------- protokół chat/completions

def test_local_provider_generates(chat_ok):
    p = ChatCompletionsProvider("local", "http://localhost:11434/v1", "m", leaves_lan=False)
    out = p.generate("prompt", 500)
    assert isinstance(out, Completion)
    assert out.text == "Horoskop testowy."
    assert out.usage["completion_tokens"] == 50


def test_local_provider_does_not_leave_lan(chat_ok):
    p = ChatCompletionsProvider("local", "http://localhost:11434/v1", "m", leaves_lan=False)
    assert p.generate("prompt", 100).leaves_lan is False


def test_cloud_provider_marks_leaving_lan(chat_ok):
    p = ChatCompletionsProvider("openai", "https://api.openai.com/v1", "m", "klucz",
                                leaves_lan=True)
    assert p.generate("prompt", 100).leaves_lan is True


def test_api_key_sent_only_when_set(monkeypatch):
    seen = {}

    def handler(request):
        seen["auth"] = request.headers.get("authorization")
        return httpx.Response(200, json={"choices": [{"message": {"content": "x"}}]})

    monkeypatch.setattr(httpx, "Client", _mock_client(handler))
    ChatCompletionsProvider("local", "http://x/v1", "m").generate("p", 10)
    assert seen["auth"] is None
    ChatCompletionsProvider("openai", "http://x/v1", "m", "tajny").generate("p", 10)
    assert seen["auth"] == "Bearer tajny"


def test_http_error_becomes_readable_message(monkeypatch):
    monkeypatch.setattr(httpx, "Client",
                        _mock_client(lambda r: httpx.Response(400, text="zly model")))
    with pytest.raises(LLMError, match="400"):
        ChatCompletionsProvider("local", "http://x/v1", "m").generate("p", 10)


def test_malformed_response_reported(monkeypatch):
    monkeypatch.setattr(httpx, "Client",
                        _mock_client(lambda r: httpx.Response(200, json={"nonsens": 1})))
    with pytest.raises(LLMError, match="kształt"):
        ChatCompletionsProvider("local", "http://x/v1", "m").generate("p", 10)


def test_retries_then_succeeds(monkeypatch):
    calls = {"n": 0}

    def handler(request):
        calls["n"] += 1
        if calls["n"] < 3:
            return httpx.Response(429, text="za duzo")
        return httpx.Response(200, json={"choices": [{"message": {"content": "ok"}}]})

    monkeypatch.setattr(httpx, "Client", _mock_client(handler))
    monkeypatch.setattr("app.llm.providers.time.sleep", lambda s: None)   # bez czekania
    assert ChatCompletionsProvider("local", "http://x/v1", "m").generate("p", 10).text == "ok"
    assert calls["n"] == 3


# ------------------------------------------------------------------- Anthropic

def test_anthropic_generates(monkeypatch):
    def handler(request):
        assert request.url.path.endswith("/v1/messages")
        assert request.headers.get("x-api-key") == "klucz"
        assert request.headers.get("anthropic-version")
        return httpx.Response(200, json={
            "model": "claude-x",
            "content": [{"type": "text", "text": "Prognoza."}],
            "usage": {"input_tokens": 10, "output_tokens": 5},
        })

    monkeypatch.setattr(httpx, "Client", _mock_client(handler))
    out = AnthropicProvider("https://api.anthropic.com", "claude-x", "klucz").generate("p", 100)
    assert out.text == "Prognoza." and out.leaves_lan is True


def test_anthropic_requires_key():
    with pytest.raises(LLMError, match="LLM_API_KEY"):
        AnthropicProvider("https://api.anthropic.com", "m", "").generate("p", 10)


# --------------------------------------------------------------------- fabryka

def test_default_provider_is_local(monkeypatch):
    monkeypatch.delenv("LLM_PROVIDER", raising=False)
    monkeypatch.delenv("LLM_MODEL", raising=False)
    monkeypatch.delenv("LLM_BASE_URL", raising=False)
    p = factory.build_provider()
    assert p.name == "local"
    # domyślnie NIC nie opuszcza sieci — prompt niesie opisy z baz (LOG-32)
    assert p.leaves_lan is False


def test_openai_requires_key(monkeypatch):
    monkeypatch.delenv("LLM_API_KEY", raising=False)
    with pytest.raises(LLMError, match="LLM_API_KEY"):
        factory.build_provider("openai")


def test_unknown_provider_rejected():
    with pytest.raises(LLMError, match="Nieznany dostawca"):
        factory.build_provider("bzdura")


def test_env_overrides_model_and_url(monkeypatch):
    monkeypatch.setenv("LLM_MODEL", "moj-model")
    monkeypatch.setenv("LLM_BASE_URL", "http://serwer:8000/v1")
    p = factory.build_provider("local")
    assert p.model == "moj-model" and p.base_url == "http://serwer:8000/v1"