from __future__ import annotations

from fastapi.testclient import TestClient

from nexus_claude_api.config import Settings
from nexus_claude_api.server import create_app


class FakeNexusClient:
    def converse(self, request: dict) -> dict:
        assert request["messages"][0]["content"][0]["text"] == "Hello"
        return {
            "ResponseMetadata": {"RequestId": "req-route"},
            "output": {"message": {"content": [{"text": "Hi"}]}},
            "stopReason": "end_turn",
            "usage": {"inputTokens": 3, "outputTokens": 1},
        }

    def converse_stream(self, request: dict):
        assert request["messages"][0]["content"][0]["text"] == "Hello"
        return [
            {"contentBlockDelta": {"contentBlockIndex": 0, "delta": {"text": "Hi"}}},
            {"contentBlockStop": {"contentBlockIndex": 0}},
            {"messageStop": {"stopReason": "end_turn"}},
        ]


def client() -> TestClient:
    settings = Settings.from_values(api_key="test", require_api_key=False)
    return TestClient(create_app(settings=settings, nexus_client=FakeNexusClient()))


def test_health() -> None:
    response = client().get("/health")
    assert response.status_code == 200
    assert response.json() == {"status": "ok"}


def test_models() -> None:
    response = client().get("/v1/models")
    assert response.status_code == 200
    data = response.json()["data"]
    assert {model["id"] for model in data} >= {
        "claude-sonnet-4.6",
        "claude-opus-4.6",
        "claude-haiku-4.5",
    }


def test_messages_non_stream() -> None:
    response = client().post(
        "/v1/messages",
        json={
            "model": "claude-sonnet-4.6",
            "messages": [{"role": "user", "content": "Hello"}],
            "max_tokens": 32,
        },
    )

    assert response.status_code == 200
    body = response.json()
    assert body["id"] == "req-route"
    assert body["content"][0]["text"] == "Hi"


def test_messages_stream() -> None:
    with client().stream(
        "POST",
        "/v1/messages",
        json={
            "model": "claude-sonnet-4.6",
            "messages": [{"role": "user", "content": "Hello"}],
            "max_tokens": 32,
            "stream": True,
        },
    ) as response:
        body = response.read().decode("utf-8")

    assert response.status_code == 200
    assert "event: message_start" in body
    assert "event: content_block_delta" in body
    assert "event: message_stop" in body


def test_count_tokens() -> None:
    response = client().post(
        "/v1/messages/count_tokens",
        json={
            "model": "claude-sonnet-4.6",
            "messages": [{"role": "user", "content": "Hello"}],
        },
    )

    assert response.status_code == 200
    assert response.json()["input_tokens"] > 0