from __future__ import annotations

import copy

import pytest

from tools.graphrag.evaluation.freeze_graphrag import make_freeze
from tools.graphrag.evaluation.reproducibility import sha256_file, verify_freeze


@pytest.fixture
def freeze_case():
    questions = [{"id": "development-a", "split": "dev"}, {"id": "holdout-a", "split": "test"}]
    fingerprints = {
        "implementation": {"search.py": "version-one"},
        "dataset_sha256": "dataset",
        "inputs": {},
    }
    graph = {"sha256": "graph", "nodes": 1, "relationships": 0}
    audit = {
        "questions": [{"id": q["id"]} for q in questions],
        "by_split": {},
        "dataset_sha256": "dataset",
        "inputs": {},
    }
    dev = {
        "configuration": {"split": "dev", "limit": 40, "max_entities": 8},
        "summary": {"error_count": 0},
        "questions": [{"id": "development-a", "error": None}],
        "run_metadata": {"fingerprints": fingerprints, "graph": graph},
    }
    return questions, fingerprints, graph, audit, dev


def test_freeze_rejects_partial_dev(freeze_case):
    questions, fingerprints, _, audit, dev = freeze_case
    dev["questions"] = []
    with pytest.raises(RuntimeError, match="complete DEV"):
        make_freeze(dev, questions, fingerprints, audit)


def test_freeze_rejects_runtime_errors(freeze_case):
    questions, fingerprints, _, audit, dev = freeze_case
    dev["questions"][0]["error"] = "database unavailable"
    with pytest.raises(RuntimeError, match="runtime errors"):
        make_freeze(dev, questions, fingerprints, audit)


def test_freeze_rejects_code_changed_after_dev(freeze_case):
    questions, fingerprints, _, audit, dev = freeze_case
    changed = copy.deepcopy(fingerprints)
    changed["implementation"]["search.py"] = "version-two"
    with pytest.raises(RuntimeError, match="changed after DEV"):
        make_freeze(dev, questions, changed, audit)


def test_freeze_rejects_stale_source_audit(freeze_case):
    questions, fingerprints, _, audit, dev = freeze_case
    audit["inputs"] = {"documents": "old-snapshot"}
    with pytest.raises(RuntimeError, match="audit does not match"):
        make_freeze(dev, questions, fingerprints, audit)


@pytest.mark.parametrize("mutation", ["code", "graph", "parameters", "audit"])
def test_holdout_rejects_changes_after_freeze(freeze_case, tmp_path, mutation):
    questions, fingerprints, graph, audit, dev = freeze_case
    manifest = make_freeze(dev, questions, fingerprints, audit)
    audit_path = tmp_path / "audit.json"
    audit_path.write_text("original-audit")
    manifest["audit_sha256"] = sha256_file(audit_path)
    metadata = {"fingerprints": copy.deepcopy(fingerprints)}
    actual_graph = dict(graph)
    limit = 40
    if mutation == "code":
        metadata["fingerprints"]["implementation"]["search.py"] = "changed"
    elif mutation == "graph":
        actual_graph["sha256"] = "changed"
    elif mutation == "parameters":
        limit = 41
    else:
        audit_path.write_text("changed-audit")
    with pytest.raises(RuntimeError, match="TEST refused"):
        verify_freeze(
            manifest, metadata, actual_graph, limit=limit, max_entities=8, audit=audit_path
        )