"""Tests for stage-5 conjecture generation.

HARD invariant: every conjecture MUST carry status='unverified', a
non-empty suggested_validation, and non-empty provenance.
"""

from __future__ import annotations

from pathlib import Path

from codex.synthesis import _parse_conjecture_output, propose_conjectures
from tests.synthesis.conftest import StubLLM

_VALID_CONJECTURE = (
    "Title: A discrete cosmetic-surgery analogue exists for Yamabe flows.\n"
    "Body: The combinatorial Yamabe flow [Luo2004 #chunk 0] is a discrete "
    "analogue of conformal change. One could hope the cosmetic surgery "
    "conjecture has a discrete formulation in this setting.\n"
    "Validation: Search for a counter-example among simplicial 3-manifolds "
    "with at most 12 tetrahedra using a CSP solver."
)

_MISSING_VALIDATION = (
    "Title: A naive idea.\n"
    "Body: Some thoughts that follow [Luo2004 #chunk 0]. No falsification path "
    "is described."
)


def test_parse_valid_conjecture_output() -> None:
    """_parse_conjecture_output extracts title / body / validation."""
    parsed = _parse_conjecture_output(_VALID_CONJECTURE)
    assert parsed is not None
    title, body, validation = parsed
    assert title.startswith("A discrete cosmetic-surgery")
    assert "Luo2004" in body
    assert "counter-example" in validation


def test_parse_conjecture_missing_validation_returns_none() -> None:
    """Output without a Validation: line is rejected."""
    assert _parse_conjecture_output(_MISSING_VALIDATION) is None


def test_parse_conjecture_empty_input() -> None:
    """Empty LLM output → None."""
    assert _parse_conjecture_output("") is None


def test_propose_conjectures_marks_status_unverified(
    mock_retrieve: None,
    mock_paper_titles: None,
    mock_settings: Path,
) -> None:
    """Every emitted conjecture has status='unverified'."""
    llm = StubLLM(_VALID_CONJECTURE)
    leads = propose_conjectures(top_k=6, llm=llm)
    assert len(leads) >= 1
    for lead in leads:
        assert lead.kind == "conjecture"
        assert lead.status == "unverified"


def test_propose_conjectures_requires_validation(
    mock_retrieve: None,
    mock_paper_titles: None,
    mock_settings: Path,
) -> None:
    """Every emitted conjecture has a non-empty suggested_validation."""
    llm = StubLLM(_VALID_CONJECTURE)
    leads = propose_conjectures(top_k=6, llm=llm)
    assert len(leads) >= 1
    for lead in leads:
        assert lead.suggested_validation.strip() != ""


def test_propose_conjectures_requires_provenance(
    mock_retrieve: None,
    mock_paper_titles: None,
    mock_settings: Path,
) -> None:
    """Every conjecture has at least one Provenance entry (seed chunks)."""
    llm = StubLLM(_VALID_CONJECTURE)
    leads = propose_conjectures(top_k=6, llm=llm)
    assert len(leads) >= 1
    for lead in leads:
        assert len(lead.provenance) >= 1


def test_propose_conjectures_drops_when_validation_missing(
    mock_retrieve: None,
    mock_paper_titles: None,
    mock_settings: Path,
) -> None:
    """LLM output without a Validation: line is rejected (zero leads)."""
    llm = StubLLM(_MISSING_VALIDATION)
    leads = propose_conjectures(top_k=6, llm=llm)
    assert leads == []


def test_propose_conjectures_handles_llm_failure(
    mock_retrieve: None,
    mock_paper_titles: None,
    mock_settings: Path,
) -> None:
    """LLM raising → returns [] (mirrors F-12 graceful degradation)."""

    class FailingLLM:
        def generate(self, prompt: str, model: str) -> str:
            raise ConnectionError("ollama unreachable")

    leads = propose_conjectures(top_k=6, llm=FailingLLM())
    assert leads == []