import unittest
from typing import Any
from unittest.mock import patch, MagicMock
import json
import subprocess
import io
import sys
import os

# Ensure the project root is in sys.path to resolve imports correctly
sys.path.append(os.path.abspath(os.path.join(os.path.dirname(__file__), "..")))

from gemini_cli_adapter import GeminiCliAdapter

class TestGeminiCliAdapter(unittest.TestCase):
 def setUp(self) -> None:
  self.adapter = GeminiCliAdapter(binary_path="gemini")

 @patch('subprocess.Popen')
 def test_send_starts_subprocess_with_correct_args(self, mock_popen: Any) -> None:
  """
  Verify that send(message) correctly starts the subprocess with 
  --output-format stream-json and the provided message via stdin.
  """
  # Setup mock process with a minimal valid JSONL termination
  process_mock = MagicMock()
  jsonl_output = [json.dumps({"type": "result", "usage": {}}) + "\n"]
  process_mock.stdout.readline.side_effect = jsonl_output + ['']
  process_mock.stderr.read.return_value = ""
  process_mock.poll.return_value = 0
  process_mock.wait.return_value = 0
  mock_popen.return_value = process_mock
  
  message = "Hello Gemini CLI"
  self.adapter.send(message)
  
  # Verify subprocess.Popen call
  mock_popen.assert_called_once()
  args, kwargs = mock_popen.call_args
  cmd = args[0]
  
  # Check mandatory CLI components
  self.assertIn("gemini", cmd)
  self.assertIn("--output-format", cmd)
  self.assertIn("stream-json", cmd)
  
  # Message should NOT be in cmd now
  self.assertNotIn(message, cmd)
  
  # Verify message was written to stdin
  process_mock.stdin.write.assert_called_with(message)
  
  # Check process configuration
  self.assertEqual(kwargs.get('stdout'), subprocess.PIPE)
  self.assertEqual(kwargs.get('stdin'), subprocess.PIPE)
  self.assertEqual(kwargs.get('text'), True)

 @patch('subprocess.Popen')
 def test_send_parses_jsonl_output(self, mock_popen: Any) -> None:
  """
  Verify that it correctly parses multiple JSONL 'message' events 
  and returns the combined text.
  """
  jsonl_output = [
   json.dumps({"type": "message", "role": "model", "text": "The quick brown "}) + "\n",
   json.dumps({"type": "message", "role": "model", "text": "fox jumps."}) + "\n",
   json.dumps({"type": "result", "usage": {"prompt_tokens": 5, "candidates_tokens": 5}}) + "\n"
  ]
  process_mock = MagicMock()
  process_mock.stdout.readline.side_effect = jsonl_output + ['']
  process_mock.stderr.read.return_value = ""
  process_mock.poll.return_value = 0
  process_mock.wait.return_value = 0
  mock_popen.return_value = process_mock
  
  result = self.adapter.send("test message")
  self.assertEqual(result["text"], "The quick brown fox jumps.")
  self.assertEqual(result["tool_calls"], [])

 @patch('subprocess.Popen')
 def test_send_handles_tool_use_events(self, mock_popen: Any) -> None:
  """
  Verify that it correctly handles 'tool_use' events in the stream 
  by continuing to read until the final 'result' event.
  """
  jsonl_output = [
   json.dumps({"type": "message", "role": "assistant", "text": "Calling tool..."}) + "\n",
   json.dumps({"type": "tool_use", "name": "read_file", "args": {"path": "test.txt"}}) + "\n",
   json.dumps({"type": "message", "role": "assistant", "text": "\nFile read successfully."}) + "\n",
   json.dumps({"type": "result", "usage": {}}) + "\n"
  ]
  process_mock = MagicMock()
  process_mock.stdout.readline.side_effect = jsonl_output + ['']
  process_mock.stderr.read.return_value = ""
  process_mock.poll.return_value = 0
  process_mock.wait.return_value = 0
  mock_popen.return_value = process_mock
  
  result = self.adapter.send("read test.txt")
  # Result should contain the combined text from all 'message' events
  self.assertEqual(result["text"], "Calling tool...\nFile read successfully.")
  self.assertEqual(len(result["tool_calls"]), 1)
  self.assertEqual(result["tool_calls"][0]["name"], "read_file")

 @patch('subprocess.Popen')
 def test_send_captures_usage_metadata(self, mock_popen: Any) -> None:
  """
  Verify that usage data is extracted from the 'result' event.
  """
  usage_data = {"total_tokens": 42}
  jsonl_output = [
   json.dumps({"type": "message", "text": "Finalizing"}) + "\n",
   json.dumps({"type": "result", "usage": usage_data}) + "\n"
  ]
  process_mock = MagicMock()
  process_mock.stdout.readline.side_effect = jsonl_output + ['']
  process_mock.stderr.read.return_value = ""
  process_mock.poll.return_value = 0
  process_mock.wait.return_value = 0
  mock_popen.return_value = process_mock
  
  self.adapter.send("usage test")
  # Verify the usage was captured in the adapter instance
  self.assertEqual(self.adapter.last_usage, usage_data)

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