import json
import unittest
from urllib.error import HTTPError
from unittest.mock import patch

from fgai.graylog_mcp import GraylogMcpClient


class _Response:
    def __init__(self, body: dict[str, object], session: str = "session-1") -> None:
        self.body = body
        self.headers = {"Mcp-Session-Id": session}

    def read(self) -> bytes:
        return json.dumps(self.body).encode("utf-8")

    def __enter__(self):
        return self

    def __exit__(self, *_args):
        return False


class GraylogMcpTests(unittest.TestCase):
    def test_accepts_raw_or_copied_basic_credentials(self):
        raw = GraylogMcpClient("http://graylog/api/mcp", "raw-token")._authorization_header()
        encoded = raw.removeprefix("Basic ")
        self.assertEqual(GraylogMcpClient("http://graylog/api/mcp", encoded)._authorization_header(), raw)
        self.assertEqual(GraylogMcpClient("http://graylog/api/mcp", raw)._authorization_header(), raw)

    def test_probe_initializes_and_lists_tools(self):
        responses = iter([
            _Response({"result": {"serverInfo": {"version": "7.1.6"}}}),
            _Response({}),
            _Response({"result": {"tools": [{"name": "search_messages"}, {"name": "aggregate_messages"}]}}),
        ])
        with patch("fgai.graylog_mcp.request.urlopen", side_effect=responses):
            status = GraylogMcpClient("http://graylog/api/mcp", "raw-token").probe()
        self.assertEqual(status["status"], "connected")
        self.assertIn("search_messages", status["tools"])

    def test_probe_keeps_existing_session_unless_forced(self):
        responses = iter([
            _Response({"result": {"serverInfo": {"version": "7.1.6"}}}, session="session-1"),
            _Response({}, session="session-1"),
            _Response({"result": {"tools": []}}, session="session-1"),
        ])
        client = GraylogMcpClient("http://graylog/api/mcp", "raw-token")
        client.session_id = "existing-session"

        with patch("fgai.graylog_mcp.request.urlopen", side_effect=responses):
            client.probe()

        self.assertEqual(client.session_id, "session-1")

    def test_call_tool_reinitializes_after_stale_session_error(self):
        responses = iter([
            HTTPError("http://graylog/api/mcp", 404, "stale session", {}, None),
            _Response({"result": {"serverInfo": {"version": "7.1.6"}}}, session="session-2"),
            _Response({}, session="session-2"),
            _Response({"result": {"tools": [{"name": "search_messages"}]}}, session="session-2"),
            _Response({"result": {"content": []}}, session="session-2"),
        ])
        client = GraylogMcpClient("http://graylog/api/mcp", "raw-token")
        client.session_id = "old-session"

        with patch("fgai.graylog_mcp.request.urlopen", side_effect=responses):
            result = client.call_tool("search_messages", {"query": "*"})

        self.assertEqual(result["result"]["content"], [])
        self.assertEqual(client.session_id, "session-2")


if __name__ == "__main__":
    unittest.main()