"""Tests for POST /api/score endpoint."""
from __future__ import annotations

import pytest
from pydantic import ValidationError

from webapp.models import ScoreRequest, ScoreResponse


class TestScoreRequest:
    def test_minimal_valid_request(self):
        """Only required fields — question, answer, contexts."""
        req = ScoreRequest(
            question="What is CT?",
            answer="CT is imaging.",
            contexts="CT uses X-rays.",
        )
        assert req.question == "What is CT?"
        assert req.contexts == "CT uses X-rays."
        assert req.ground_truth is None
        assert req.context_separator == " |||| "
        assert req.metrics == [
            "faithfulness",
            "answer_relevancy",
            "context_recall",
            "context_precision",
        ]

    def test_contexts_split_by_separator(self):
        """contexts_as_list() splits on context_separator."""
        req = ScoreRequest(
            question="q",
            answer="a",
            contexts="ctx1 |||| ctx2 |||| ctx3",
            context_separator=" |||| ",
        )
        assert req.contexts_as_list() == ["ctx1", "ctx2", "ctx3"]

    def test_contexts_split_custom_separator(self):
        req = ScoreRequest(
            question="q",
            answer="a",
            contexts="a---b---c",
            context_separator="---",
        )
        assert req.contexts_as_list() == ["a", "b", "c"]

    def test_contexts_split_single_item(self):
        req = ScoreRequest(question="q", answer="a", contexts="only one")
        assert req.contexts_as_list() == ["only one"]

    def test_missing_question_raises(self):
        with pytest.raises(ValidationError):
            ScoreRequest(answer="a", contexts="c")  # type: ignore[call-arg]

    def test_missing_answer_raises(self):
        with pytest.raises(ValidationError):
            ScoreRequest(question="q", contexts="c")  # type: ignore[call-arg]

    def test_missing_contexts_raises(self):
        with pytest.raises(ValidationError):
            ScoreRequest(question="q", answer="a")  # type: ignore[call-arg]

    def test_custom_metrics_accepted(self):
        req = ScoreRequest(
            question="q",
            answer="a",
            contexts="c",
            metrics=["faithfulness"],
        )
        assert req.metrics == ["faithfulness"]

    def test_invalid_metric_name_raises(self):
        with pytest.raises(ValidationError):
            ScoreRequest(
                question="q",
                answer="a",
                contexts="c",
                metrics=["not_a_metric"],
            )

    def test_effective_metrics_drops_ground_truth_dependent_when_missing(self):
        """Without ground_truth, GT-dependent metrics are excluded."""
        req = ScoreRequest(
            question="q",
            answer="a",
            contexts="c",
            metrics=[
                "faithfulness",
                "context_recall",
                "factual_correctness",
                "semantic_similarity",
                "noise_sensitivity",
            ],
        )
        effective = req.effective_metrics()
        assert "faithfulness" in effective
        assert "context_recall" not in effective
        assert "factual_correctness" not in effective
        assert "semantic_similarity" not in effective
        assert "noise_sensitivity" not in effective

    def test_effective_metrics_keeps_all_when_ground_truth_present(self):
        req = ScoreRequest(
            question="q",
            answer="a",
            contexts="c",
            ground_truth="gt",
            metrics=["faithfulness", "context_recall", "factual_correctness"],
        )
        effective = req.effective_metrics()
        assert effective == [
            "faithfulness",
            "context_recall",
            "factual_correctness",
        ]


class TestScoreResponse:
    def test_score_response_structure(self):
        resp = ScoreResponse(
            scores={"faithfulness": 0.85, "answer_relevancy": None},
            weighted_score=0.85,
            latency_ms=1200,
        )
        assert resp.scores["faithfulness"] == 0.85
        assert resp.scores["answer_relevancy"] is None
        assert resp.latency_ms == 1200


class TestInlineScorer:
    def test_score_returns_dict_with_requested_metrics(self):
        """InlineScorer.score returns a dict keyed by the requested metrics."""
        from unittest.mock import AsyncMock, MagicMock, patch
        from webapp.services.inline_scorer import InlineScorer
        from rag_eval.settings import EvaluationSettings

        mock_score = MagicMock()
        mock_score.metrics = {"faithfulness": 0.9, "answer_relevancy": 0.8}
        mock_score.error = ""

        mock_pipeline = MagicMock()
        mock_pipeline.score_sample = AsyncMock(return_value=mock_score)

        with patch("webapp.services.inline_scorer.build_models", return_value=(MagicMock(), MagicMock())):
            with patch("webapp.services.inline_scorer.MetricPipeline", return_value=mock_pipeline):
                with patch("webapp.services.inline_scorer._build_metric_instances", return_value={}):
                    scorer = InlineScorer()
                    result = scorer.score(
                        question="q", answer="a",
                        contexts=["ctx1"],
                        ground_truth=None,
                        metrics=["faithfulness", "answer_relevancy"],
                        judge_model="test-model",
                        embedding_model="test-embed",
                        settings=EvaluationSettings(_env_file=None),
                    )
        assert "faithfulness" in result
        assert "answer_relevancy" in result
        assert result["faithfulness"] == pytest.approx(0.9)

    def test_score_converts_nan_to_none(self):
        """NaN scores are converted to None in the returned dict."""
        import math
        from unittest.mock import AsyncMock, MagicMock, patch
        from webapp.services.inline_scorer import InlineScorer
        from rag_eval.settings import EvaluationSettings

        mock_score = MagicMock()
        mock_score.metrics = {"faithfulness": float("nan")}
        mock_score.error = ""

        mock_pipeline = MagicMock()
        mock_pipeline.score_sample = AsyncMock(return_value=mock_score)

        with patch("webapp.services.inline_scorer.build_models", return_value=(MagicMock(), MagicMock())):
            with patch("webapp.services.inline_scorer.MetricPipeline", return_value=mock_pipeline):
                with patch("webapp.services.inline_scorer._build_metric_instances", return_value={}):
                    scorer = InlineScorer()
                    result = scorer.score(
                        question="q", answer="a", contexts=["c"],
                        ground_truth=None,
                        metrics=["faithfulness"],
                        judge_model="m", embedding_model="e",
                        settings=EvaluationSettings(_env_file=None),
                    )
        assert result["faithfulness"] is None


# ── Endpoint integration tests ────────────────────────────────────────────────

@pytest.fixture()
def client(monkeypatch):
    """TestClient with mocked InlineScorer."""
    import webapp.api.score as score_mod
    from unittest.mock import MagicMock

    mock_scorer = MagicMock()
    mock_scorer.score.return_value = {
        "faithfulness": 0.85,
        "answer_relevancy": 0.90,
    }
    monkeypatch.setattr(score_mod, "inline_scorer", mock_scorer)

    from webapp.server import create_app
    return TestClient(create_app())


from fastapi.testclient import TestClient


class TestScoreEndpoint:
    def test_post_score_returns_200(self, client):
        resp = client.post("/api/score", json={
            "question": "What is CT?",
            "answer": "CT is imaging.",
            "contexts": "CT uses X-rays.",
        })
        assert resp.status_code == 200
        data = resp.json()
        assert "scores" in data
        assert "latency_ms" in data
        assert data["scores"]["faithfulness"] == pytest.approx(0.85)

    def test_weighted_score_computed(self, client):
        resp = client.post("/api/score", json={
            "question": "q", "answer": "a", "contexts": "c",
        })
        assert resp.status_code == 200
        data = resp.json()
        assert data["weighted_score"] is not None

    def test_missing_required_fields_returns_422(self, client):
        resp = client.post("/api/score", json={"question": "q"})
        assert resp.status_code == 422

    def test_invalid_metric_name_returns_422(self, client):
        resp = client.post("/api/score", json={
            "question": "q", "answer": "a", "contexts": "c",
            "metrics": ["not_a_metric"],
        })
        assert resp.status_code == 422

    def test_skipped_metrics_returned_when_no_ground_truth(self, client):
        resp = client.post("/api/score", json={
            "question": "q", "answer": "a", "contexts": "c",
            "metrics": ["faithfulness", "context_recall"],
        })
        assert resp.status_code == 200
        data = resp.json()
        assert "context_recall" in data["skipped_metrics"]

    def test_contexts_split_on_separator(self, monkeypatch):
        """contexts string is split before passing to scorer."""
        import webapp.api.score as score_mod
        from unittest.mock import MagicMock
        calls = []
        def capture(**kwargs):
            calls.append(kwargs.get("contexts", []))
            return {"faithfulness": 0.9}
        mock_scorer = MagicMock()
        mock_scorer.score.side_effect = lambda **kw: capture(**kw)
        monkeypatch.setattr(score_mod, "inline_scorer", mock_scorer)

        from webapp.server import create_app
        from fastapi.testclient import TestClient
        tc = TestClient(create_app())
        tc.post("/api/score", json={
            "question": "q", "answer": "a",
            "contexts": "ctx1 |||| ctx2",
            "context_separator": " |||| ",
        })
        assert len(calls) == 1
        assert calls[0] == ["ctx1", "ctx2"]

    def test_bearer_token_auth_required_when_configured(self, monkeypatch):
        """When SCORE_API_TOKEN is set, requests without token get 401."""
        import webapp.api.score as score_mod
        from rag_eval.settings import EvaluationSettings
        from unittest.mock import MagicMock

        mock_settings = EvaluationSettings(_env_file=None)
        object.__setattr__(mock_settings, "score_api_token", "secret-token")
        monkeypatch.setattr(score_mod, "_get_settings", lambda: mock_settings)

        mock_scorer = MagicMock()
        mock_scorer.score.return_value = {"faithfulness": 0.9}
        monkeypatch.setattr(score_mod, "inline_scorer", mock_scorer)

        from webapp.server import create_app
        from fastapi.testclient import TestClient
        tc = TestClient(create_app())

        # No auth header -> 401
        resp = tc.post("/api/score", json={
            "question": "q", "answer": "a", "contexts": "c",
        })
        assert resp.status_code == 401

        # Correct token -> 200
        resp = tc.post("/api/score",
            json={"question": "q", "answer": "a", "contexts": "c"},
            headers={"Authorization": "Bearer secret-token"},
        )
        assert resp.status_code == 200

    def test_wrong_bearer_token_returns_401(self, monkeypatch):
        import webapp.api.score as score_mod
        from rag_eval.settings import EvaluationSettings
        from unittest.mock import MagicMock

        mock_settings = EvaluationSettings(_env_file=None)
        object.__setattr__(mock_settings, "score_api_token", "correct-token")
        monkeypatch.setattr(score_mod, "_get_settings", lambda: mock_settings)

        mock_scorer = MagicMock()
        mock_scorer.score.return_value = {}
        monkeypatch.setattr(score_mod, "inline_scorer", mock_scorer)

        from webapp.server import create_app
        from fastapi.testclient import TestClient
        tc = TestClient(create_app())
        resp = tc.post("/api/score",
            json={"question": "q", "answer": "a", "contexts": "c"},
            headers={"Authorization": "Bearer wrong-token"},
        )
        assert resp.status_code == 401