import sys
import os
from unittest.mock import patch, MagicMock
from types import SimpleNamespace

sys.path.append(os.path.abspath(os.path.join(os.path.dirname(__file__), "..")))

from src import ai_client

def test_token_usage_tracking() -> None:
 ai_client.reset_session()
 ai_client.clear_comms_log()
 with patch("src.ai_client._ensure_gemini_client"), \
 patch("src.ai_client._gemini_client") as mock_client:
  mock_chat = MagicMock()
  mock_client.chats.create.return_value = mock_chat
  mock_usage = SimpleNamespace(
   prompt_token_count=100,
   candidates_token_count=50,
   total_token_count=150,
   cached_content_token_count=20
  )
  mock_part = SimpleNamespace(text="Mock Response", function_call=None)
  mock_content = SimpleNamespace(parts=[mock_part])
  mock_candidate = SimpleNamespace()
  mock_candidate.content = mock_content
  mock_candidate.finish_reason = SimpleNamespace(name="STOP")
  mock_response = SimpleNamespace()
  mock_response.candidates = [mock_candidate]
  mock_response.usage_metadata = mock_usage
  mock_response.text = "Mock Response"
  mock_chat.send_message.return_value = mock_response
  ai_client.set_provider("gemini", "gemini-2.5-flash-lite")
  ai_client.send("Context", "Hello")
  comms = ai_client.get_comms_log()
  response_entries = [e for e in comms if e.get("direction") == "IN" and e["kind"] == "response"]
  assert len(response_entries) > 0
  usage = response_entries[0]["payload"]["usage"]
  assert usage["input_tokens"] == 100
  assert usage["output_tokens"] == 50
  assert usage["cache_read_input_tokens"] == 20
