"""Check the public signer and migration without connecting to a configured database."""

import importlib.util
from io import StringIO
from pathlib import Path

import httpx
from alembic.migration import MigrationContext
from alembic.operations import Operations
from app.services.integration_auth import signature_message
from fastapi import Request
from scripts.call_external_follow_up import sign_follow_up_request
from sqlalchemy import create_engine, inspect


def test_client_signature_matches_server_for_encoded_url_and_non_ascii_body():
    import base64
    import hashlib
    import hmac

    url = httpx.URL("http://test/api/v1/integrations/risk-assessments/follow-up")
    body = '{"content":"总结原报告"}'.encode()
    timestamp, nonce, secret = "1793145600", "nonce-with-32-valid-characters-123", "test-secret-" * 4
    request = Request(
        {
            "type": "http",
            "method": "POST",
            "scheme": "http",
            "server": ("test", 80),
            "path": url.path,
            "raw_path": url.raw_path.partition(b"?")[0],
            "query_string": url.query,
            "headers": [],
        }
    )
    signed = sign_follow_up_request("POST", url, "dieya-plm", secret, body, timestamp=timestamp, nonce=nonce)
    canonical = signature_message(request, timestamp, nonce, body)
    assert signed["X-Signature-Version"] == "2"
    assert (
        signed["X-Signature"]
        == base64.b64encode(hmac.new(secret.encode(), canonical, hashlib.sha256).digest()).decode()
    )


def test_documented_signature_example_is_executable_and_matches_server():
    from unittest.mock import patch

    root = Path(__file__).resolve().parents[1]
    doc = (root / "docs" / "外部系统风险评估报告接口.md").read_text(encoding="utf-8")
    examples = [part.split("```", 1)[0] for part in doc.split("```python\n")[1:]]
    example = next(part for part in examples if "def sign_follow_up_request" in part)
    scope = {}
    exec(compile(example, "documented HMAC example", "exec"), scope)
    body = '{"content":"请解释"}'.encode()
    target = "/api/v1/integrations/risk-assessments/follow-up"
    with patch("time.time", return_value=1793145600), patch("secrets.token_urlsafe", return_value="fixed-nonce-123"):
        documented = scope["sign_follow_up_request"]("POST", target, body, "dieya-plm", "secret" * 8)
    expected = sign_follow_up_request(
        "POST",
        httpx.URL("http://test" + target),
        "dieya-plm",
        "secret" * 8,
        body,
        timestamp="1793145600",
        nonce="fixed-nonce-123",
    )
    assert documented == expected


def test_migration_postgresql_ddl_and_upgrade_downgrade_preserve_existing_tables():
    root = Path(__file__).resolve().parents[1]
    filename = root / "migrations" / "versions" / "20261028_0023_integration_conversations.py"
    spec = importlib.util.spec_from_file_location("integration_chat_migration", filename)
    migration = importlib.util.module_from_spec(spec)
    spec.loader.exec_module(migration)
    output = StringIO()
    context = MigrationContext.configure(dialect_name="postgresql", opts={"as_sql": True, "output_buffer": output})
    with Operations.context(context):
        migration.upgrade()
    sql = output.getvalue()
    assert "CREATE TABLE integration_conversations" in sql
    assert "REFERENCES integration_assessments (client_id, request_id)" in sql
    assert "CREATE TABLE integration_conversation_requests" in sql

    engine = create_engine("sqlite://")
    try:
        with engine.begin() as connection:
            connection.exec_driver_sql("CREATE TABLE conversations (id BIGINT PRIMARY KEY)")
            connection.exec_driver_sql(
                "CREATE TABLE integration_assessments (client_id TEXT, request_id TEXT, UNIQUE(client_id, request_id))"
            )
            with Operations.context(MigrationContext.configure(connection)):
                migration.upgrade()
                assert len(inspect(connection).get_columns("integration_conversation_requests")) == 14
                migration.downgrade()
            assert set(inspect(connection).get_table_names()) == {"conversations", "integration_assessments"}
    finally:
        engine.dispose()