from pathlib import Path
import json

import pytest
from django.core.management import call_command

from review_agent.models import RegulatoryRuleVersion
from review_agent.regulatory_review.services.rule_loader import (
    DEFAULT_RULE_CODE,
    check_rule_version,
    compute_file_sha256,
    load_rule_file,
)


pytestmark = pytest.mark.django_db


def test_load_rule_file_reads_demo_requirements():
    rule_set = load_rule_file()

    codes = {item["code"] for item in rule_set["requirements"]}
    assert rule_set["code"] == DEFAULT_RULE_CODE
    assert "product_technical_requirements" in codes
    assert "instructions_for_use" in codes
    assert "registration_test_report" in codes
    assert "clinical_evaluation" in codes
    assert "essential_principles_checklist" in codes


def test_load_rule_file_covers_attachment4_outline():
    rule_set = load_rule_file()
    requirements = rule_set["requirements"]
    outline = json.loads(Path("tests/fixtures/regulatory/attachment4_outline.json").read_text(encoding="utf-8"))

    for chapter in outline:
        chapter_rule = next(
            item for item in requirements if item["title"] == chapter["title"] and item.get("attachment4_code") == chapter["code"]
        )
        assert chapter_rule["attachment4_code"] == chapter["code"]
        assert chapter_rule["severity"] == "high"
        assert chapter_rule["citation_query"]
        for child in chapter["children"]:
            child_rule = next(
                item
                for item in requirements
                if item["title"] == child and str(item.get("attachment4_code", "")).startswith(f"{chapter['code']}.")
            )
            assert child_rule["rule_id"]
            assert child_rule["file_keywords"]
            assert child_rule["severity"] in {"blocking", "high", "medium"}
            assert child_rule["citation_query"]


def test_compute_file_sha256_changes_when_file_changes(tmp_path):
    path = tmp_path / "rule.yaml"
    path.write_text("code: demo\n", encoding="utf-8")
    first = compute_file_sha256(path)
    path.write_text("code: demo2\n", encoding="utf-8")

    assert compute_file_sha256(path) != first


def test_check_rule_version_creates_missing_db_record():
    result = check_rule_version(update_missing=True)

    record = RegulatoryRuleVersion.objects.get(code=DEFAULT_RULE_CODE)
    assert result.status == "created"
    assert result.current_hash == record.yaml_hash
    assert record.rag_collection == "nmpa_ivd_registration_v1"


def test_check_rule_version_reports_hash_mismatch_without_overwriting():
    created = check_rule_version(update_missing=True)
    record = RegulatoryRuleVersion.objects.get(code=DEFAULT_RULE_CODE)
    record.yaml_hash = "stale"
    record.save(update_fields=["yaml_hash"])

    result = check_rule_version(update_missing=False)
    record.refresh_from_db()

    assert result.status == "mismatch"
    assert result.database_hash == "stale"
    assert result.current_hash == created.current_hash
    assert record.yaml_hash == "stale"


def test_regulatory_rules_check_command_reports_status(capsys):
    call_command("regulatory_rules_check")

    captured = capsys.readouterr()
    assert DEFAULT_RULE_CODE in captured.out
    assert "created" in captured.out or "ok" in captured.out