"""Tests for the vLLM client, health check, config, and LLM factory."""
import json
import logging
from unittest.mock import patch

import httpx
import pytest

from services.extractor.client import OllamaClient
from services.extractor.llm_factory import build_llm_client
from services.extractor.vllm_client import VLLMClient, check_vllm_health
from services.shared.agent_config import ResolvedAgentConfig
from services.shared.config import AppConfig, OllamaConfig, VLLMConfig, load_config

# ---------------------------------------------------------------------------
# Helpers
# ---------------------------------------------------------------------------


def _valid_extraction_json() -> str:
    """Minimal valid extraction result as JSON string."""
    return json.dumps({
        "summary": "Apple beat earnings expectations.",
        "companies": [
            {
                "ticker": "AAPL",
                "company_name": "Apple Inc.",
                "relevance": 0.95,
                "sentiment": "positive",
                "impact_score": 0.7,
                "impact_horizon": "1d_30d",
                "catalyst_type": "earnings",
                "key_facts": ["Revenue up 12%"],
                "risks": [],
                "evidence_spans": ["Apple beat expectations"],
            }
        ],
        "macro_themes": ["ai_capex"],
        "novelty_score": 0.6,
        "confidence": 0.85,
        "extraction_warnings": [],
    })


def _openai_response(content: str, status: int = 200) -> httpx.Response:
    """Build a fake OpenAI-compatible /v1/chat/completions response."""
    body = {
        "choices": [
            {"message": {"role": "assistant", "content": content}}
        ],
    }
    return httpx.Response(status, json=body)


def _make_vllm_config() -> VLLMConfig:
    return VLLMConfig(
        base_url="http://test-vllm:8000",
        model="test-vllm-model",
        timeout=10,
        max_retries=2,
        retry_base_delay=0.0,
        retry_max_delay=0.0,
        retry_backoff_multiplier=2.0,
        max_tokens=4096,
        temperature=0.7,
        api_key="",
    )


def _make_ollama_config() -> OllamaConfig:
    return OllamaConfig(
        base_url="http://test-ollama:11434",
        model="test-ollama-model",
        timeout=10,
        retry_base_delay=0.0,
        retry_max_delay=0.0,
        retry_backoff_multiplier=2.0,
    )


def _make_prompts() -> dict[str, str]:
    return {"system": "You are a helpful assistant.", "user": "Extract info."}


def _make_resolved(provider: str = "vllm") -> ResolvedAgentConfig:
    return ResolvedAgentConfig(
        agent_id="agent-1",
        variant_id=None,
        model_provider=provider,
        model_name="resolved-model",
        system_prompt="sys",
        user_prompt_template="usr",
        prompt_version="v1",
        temperature=0.5,
        max_tokens=8192,
        context_window=0,
        input_token_limit=0,
        token_budget=0,
        timeout_seconds=60,
        max_retries=2,
    )


# ===================================================================
# Task 7: Unit Tests for VLLMClient
# ===================================================================


# 7.1 — VLLMClient sends correct payload to /v1/chat/completions
@pytest.mark.asyncio
async def test_vllm_sends_correct_payload():
    """VLLMClient sends POST to /v1/chat/completions with correct OpenAI payload."""
    captured: dict = {}

    def handler(request: httpx.Request) -> httpx.Response:
        captured["url"] = str(request.url)
        captured["payload"] = json.loads(request.content)
        return _openai_response(_valid_extraction_json())

    transport = httpx.MockTransport(handler)
    http = httpx.AsyncClient(transport=transport)
    config = _make_vllm_config()
    client = VLLMClient(config, http_client=http)

    await client.call_llm(_make_prompts(), {})

    assert captured["url"] == "http://test-vllm:8000/v1/chat/completions"
    payload = captured["payload"]
    assert payload["model"] == "test-vllm-model"
    assert len(payload["messages"]) == 2
    assert payload["messages"][0]["role"] == "system"
    assert payload["messages"][1]["role"] == "user"
    assert payload["max_tokens"] == 4096
    assert payload["temperature"] == 0.7

    await client.close()


# 7.2 — VLLMClient extracts content from choices[0].message.content
@pytest.mark.asyncio
async def test_vllm_extracts_content_from_choices():
    """VLLMClient extracts content from choices[0].message.content."""
    transport = httpx.MockTransport(
        lambda req: _openai_response(_valid_extraction_json())
    )
    http = httpx.AsyncClient(transport=transport)
    client = VLLMClient(_make_vllm_config(), http_client=http)

    attempt = await client.call_llm(_make_prompts(), {})

    assert attempt.raw_output == _valid_extraction_json()
    assert attempt.error is None
    assert attempt.validation is not None
    assert attempt.validation.valid

    await client.close()


# 7.3 — VLLMClient handles empty choices array → empty_model_response
@pytest.mark.asyncio
async def test_vllm_empty_choices():
    """Empty choices array returns empty_model_response error."""
    body = {"choices": []}

    transport = httpx.MockTransport(
        lambda req: httpx.Response(200, json=body)
    )
    http = httpx.AsyncClient(transport=transport)
    client = VLLMClient(_make_vllm_config(), http_client=http)

    attempt = await client.call_llm(_make_prompts(), {})

    assert attempt.error == "empty_model_response"

    await client.close()


# 7.4 — VLLMClient handles HTTP timeout → timeout error
@pytest.mark.asyncio
async def test_vllm_timeout():
    """HTTP timeout returns 'timeout' error."""
    def handler(request: httpx.Request) -> httpx.Response:
        raise httpx.ReadTimeout("timed out")

    transport = httpx.MockTransport(handler)
    http = httpx.AsyncClient(transport=transport)
    client = VLLMClient(_make_vllm_config(), http_client=http)

    attempt = await client.call_llm(_make_prompts(), {})

    assert attempt.error == "timeout"
    assert attempt.duration_ms >= 0

    await client.close()


# 7.5 — VLLMClient handles HTTP 500 → http_500 retryable error
@pytest.mark.asyncio
async def test_vllm_http_500():
    """HTTP 500 returns 'http_500' error marked as retryable."""
    transport = httpx.MockTransport(
        lambda req: httpx.Response(500, text="Internal Server Error")
    )
    http = httpx.AsyncClient(transport=transport)
    client = VLLMClient(_make_vllm_config(), http_client=http)

    attempt = await client.call_llm(_make_prompts(), {})

    assert attempt.error == "http_500"
    assert attempt.retryable is True

    await client.close()


# 7.6 — VLLMClient handles HTTP 400 → http_400 non-retryable error
@pytest.mark.asyncio
async def test_vllm_http_400():
    """HTTP 400 returns 'http_400' error marked as non-retryable."""
    transport = httpx.MockTransport(
        lambda req: httpx.Response(400, text="Bad Request")
    )
    http = httpx.AsyncClient(transport=transport)
    client = VLLMClient(_make_vllm_config(), http_client=http)

    attempt = await client.call_llm(_make_prompts(), {})

    assert attempt.error == "http_400"
    assert attempt.retryable is False

    await client.close()


# 7.7 — VLLMClient handles connection error → connection_error: ...
@pytest.mark.asyncio
async def test_vllm_connection_error():
    """Connection error returns 'connection_error: ...' error string."""
    def handler(request: httpx.Request) -> httpx.Response:
        raise httpx.ConnectError("Connection refused")

    transport = httpx.MockTransport(handler)
    http = httpx.AsyncClient(transport=transport)
    client = VLLMClient(_make_vllm_config(), http_client=http)

    attempt = await client.call_llm(_make_prompts(), {})

    assert attempt.error is not None
    assert attempt.error.startswith("connection_error:")

    await client.close()


# 7.8 — VLLMClient applies markdown fence stripping and JSON repair
@pytest.mark.asyncio
async def test_vllm_markdown_fence_stripping_and_json_repair():
    """VLLMClient strips markdown fences and repairs JSON."""
    # Wrap valid JSON in markdown fences
    fenced = f"```json\n{_valid_extraction_json()}\n```"
    transport = httpx.MockTransport(
        lambda req: _openai_response(fenced)
    )
    http = httpx.AsyncClient(transport=transport)
    client = VLLMClient(_make_vllm_config(), http_client=http)

    attempt = await client.call_llm(_make_prompts(), {})

    # Should succeed after stripping fences
    assert attempt.error is None
    assert attempt.validation is not None
    assert attempt.validation.valid

    await client.close()


# 7.9 — VLLMClient includes temperature and response_format in payload
@pytest.mark.asyncio
async def test_vllm_payload_includes_temperature_and_response_format():
    """Payload includes temperature and response_format fields."""
    captured: dict = {}

    def handler(request: httpx.Request) -> httpx.Response:
        captured["payload"] = json.loads(request.content)
        return _openai_response(_valid_extraction_json())

    transport = httpx.MockTransport(handler)
    http = httpx.AsyncClient(transport=transport)
    config = _make_vllm_config()
    config.temperature = 0.3
    client = VLLMClient(config, http_client=http)

    await client.call_llm(_make_prompts(), {})

    assert captured["payload"]["temperature"] == 0.3
    assert captured["payload"]["response_format"] == {"type": "json_object"}

    await client.close()


# 7.10 — Health check success returns True and logs INFO
@pytest.mark.asyncio
async def test_health_check_success(caplog):
    """check_vllm_health returns True and logs INFO on success."""
    transport = httpx.MockTransport(
        lambda req: httpx.Response(200, json={"data": [{"id": "model-1"}]})
    )

    with patch("services.extractor.vllm_client.httpx.AsyncClient", return_value=httpx.AsyncClient(transport=transport)):
        with caplog.at_level(logging.INFO, logger="vllm_client"):
            result = await check_vllm_health("http://test-vllm:8000")

    assert result is True
    assert any("health check passed" in r.message for r in caplog.records)


# 7.11 — Health check failure returns False and logs WARNING
@pytest.mark.asyncio
async def test_health_check_failure(caplog):
    """check_vllm_health returns False and logs WARNING on failure."""
    def handler(request: httpx.Request) -> httpx.Response:
        raise httpx.ConnectError("Connection refused")

    transport = httpx.MockTransport(handler)

    with patch("services.extractor.vllm_client.httpx.AsyncClient", return_value=httpx.AsyncClient(transport=transport)):
        with caplog.at_level(logging.WARNING, logger="vllm_client"):
            result = await check_vllm_health("http://unreachable:8000")

    assert result is False
    assert any("health check failed" in r.message for r in caplog.records)


# 7.12 — OllamaClient.call_llm() delegates to _call_ollama()
@pytest.mark.asyncio
async def test_ollama_call_llm_delegates():
    """OllamaClient.call_llm() delegates to _call_ollama()."""
    transport = httpx.MockTransport(
        lambda req: httpx.Response(
            200,
            json={"message": {"role": "assistant", "content": _valid_extraction_json()}},
        )
    )
    http = httpx.AsyncClient(transport=transport)
    config = _make_ollama_config()
    client = OllamaClient(config, http_client=http)

    prompts = _make_prompts()
    schema = {}

    # call_llm should produce the same result as _call_ollama
    result_llm = await client.call_llm(prompts, schema)
    # Both should succeed with valid extraction JSON
    assert result_llm.error is None
    assert result_llm.validation is not None
    assert result_llm.validation.valid
    assert result_llm.model == config.model

    await client.close()


# 7.13 — VLLMConfig loading from environment variables
def test_vllm_config_from_env(monkeypatch):
    """VLLMConfig fields are loaded from VLLM_* environment variables."""
    monkeypatch.setenv("VLLM_BASE_URL", "http://custom:9000")
    monkeypatch.setenv("VLLM_MODEL", "custom-model")
    monkeypatch.setenv("VLLM_TIMEOUT", "300")
    monkeypatch.setenv("VLLM_MAX_RETRIES", "5")
    monkeypatch.setenv("VLLM_TEMPERATURE", "0.9")
    monkeypatch.setenv("VLLM_API_KEY", "secret-key")
    monkeypatch.setenv("VLLM_MAX_TOKENS", "16384")

    cfg = load_config()

    assert cfg.vllm.base_url == "http://custom:9000"
    assert cfg.vllm.model == "custom-model"
    assert cfg.vllm.timeout == 300
    assert cfg.vllm.max_retries == 5
    assert cfg.vllm.temperature == 0.9
    assert cfg.vllm.api_key == "secret-key"
    assert cfg.vllm.max_tokens == 16384


# 7.14 — AppConfig includes vllm field with correct defaults
def test_appconfig_vllm_defaults():
    """AppConfig includes a vllm field with VLLMConfig defaults."""
    cfg = AppConfig()

    assert hasattr(cfg, "vllm")
    assert isinstance(cfg.vllm, VLLMConfig)
    assert cfg.vllm.base_url == "http://192.168.42.254:8000"
    assert cfg.vllm.model == "RedHatAI/Qwen3.6-35B-A3B-NVFP4"
    assert cfg.vllm.timeout == 120
    assert cfg.vllm.max_retries == 2
    assert cfg.vllm.temperature == 0.7
    assert cfg.vllm.max_tokens == 32768
    assert cfg.vllm.api_key == ""


# ===================================================================
# Task 8: Unit Tests for LLM Factory
# ===================================================================


# 8.1 — Factory returns OllamaClient when provider is "ollama"
@pytest.mark.asyncio
async def test_factory_ollama_provider():
    """build_llm_client returns OllamaClient when provider is 'ollama'."""
    resolved = _make_resolved(provider="ollama")
    transport = httpx.MockTransport(lambda req: httpx.Response(200))
    http = httpx.AsyncClient(transport=transport)

    client = build_llm_client(resolved, _make_ollama_config(), _make_vllm_config(), http_client=http)

    assert isinstance(client, OllamaClient)

    await client.close()


# 8.2 — Factory returns VLLMClient when provider is "vllm"
@pytest.mark.asyncio
async def test_factory_vllm_provider():
    """build_llm_client returns VLLMClient when provider is 'vllm'."""
    resolved = _make_resolved(provider="vllm")
    transport = httpx.MockTransport(lambda req: httpx.Response(200))
    http = httpx.AsyncClient(transport=transport)

    client = build_llm_client(resolved, _make_ollama_config(), _make_vllm_config(), http_client=http)

    assert isinstance(client, VLLMClient)

    await client.close()


# 8.3 — Factory returns OllamaClient when provider is empty string (default)
@pytest.mark.asyncio
async def test_factory_empty_provider_defaults_to_ollama():
    """build_llm_client returns OllamaClient when provider is empty string."""
    resolved = _make_resolved(provider="")
    transport = httpx.MockTransport(lambda req: httpx.Response(200))
    http = httpx.AsyncClient(transport=transport)

    client = build_llm_client(resolved, _make_ollama_config(), _make_vllm_config(), http_client=http)

    assert isinstance(client, OllamaClient)

    await client.close()


# 8.4 — Factory returns OllamaClient with warning when provider is unknown
@pytest.mark.asyncio
async def test_factory_unknown_provider_warns_and_falls_back(caplog):
    """build_llm_client logs warning and returns OllamaClient for unknown provider."""
    resolved = _make_resolved(provider="unknown-provider")
    transport = httpx.MockTransport(lambda req: httpx.Response(200))
    http = httpx.AsyncClient(transport=transport)

    with caplog.at_level(logging.WARNING):
        client = build_llm_client(resolved, _make_ollama_config(), _make_vllm_config(), http_client=http)

    assert isinstance(client, OllamaClient)
    assert any("unknown" in r.message.lower() for r in caplog.records)

    await client.close()