import asyncio
from unittest.mock import AsyncMock, MagicMock
from uuid import uuid4

import pytest

from openhands.controller.agent import Agent
from openhands.controller.agent_controller import AgentController
from openhands.controller.state.state import State, TrafficControlState
from openhands.core.config import AppConfig
from openhands.core.main import run_controller
from openhands.core.schema import AgentState
from openhands.events import Event, EventSource, EventStream, EventStreamSubscriber
from openhands.events.action import ChangeAgentStateAction, CmdRunAction, MessageAction
from openhands.events.observation import (
    ErrorObservation,
)
from openhands.events.serialization import event_to_dict
from openhands.llm import LLM
from openhands.llm.metrics import Metrics
from openhands.runtime.base import Runtime
from openhands.storage.memory import InMemoryFileStore


@pytest.fixture
def temp_dir(tmp_path_factory: pytest.TempPathFactory) -> str:
    return str(tmp_path_factory.mktemp('test_event_stream'))


@pytest.fixture(scope='function')
def event_loop():
    loop = asyncio.get_event_loop_policy().new_event_loop()
    yield loop
    loop.close()


@pytest.fixture
def mock_agent():
    agent = MagicMock(spec=Agent)
    agent.llm = MagicMock(spec=LLM)
    agent.llm.metrics = Metrics()
    return agent


@pytest.fixture
def mock_event_stream():
    mock = MagicMock(spec=EventStream)
    mock.get_latest_event_id.return_value = 0
    return mock


@pytest.fixture
def mock_status_callback():
    return AsyncMock()


async def send_event_to_controller(controller, event):
    await controller._on_event(event)
    await asyncio.sleep(0.1)


@pytest.mark.asyncio
async def test_set_agent_state(mock_agent, mock_event_stream):
    controller = AgentController(
        agent=mock_agent,
        event_stream=mock_event_stream,
        max_iterations=10,
        sid='test',
        confirmation_mode=False,
        headless_mode=True,
    )
    await controller.set_agent_state_to(AgentState.RUNNING)
    assert controller.get_agent_state() == AgentState.RUNNING

    await controller.set_agent_state_to(AgentState.PAUSED)
    assert controller.get_agent_state() == AgentState.PAUSED
    await controller.close()


@pytest.mark.asyncio
async def test_on_event_message_action(mock_agent, mock_event_stream):
    controller = AgentController(
        agent=mock_agent,
        event_stream=mock_event_stream,
        max_iterations=10,
        sid='test',
        confirmation_mode=False,
        headless_mode=True,
    )
    controller.state.agent_state = AgentState.RUNNING
    message_action = MessageAction(content='Test message')
    await send_event_to_controller(controller, message_action)
    assert controller.get_agent_state() == AgentState.RUNNING
    await controller.close()


@pytest.mark.asyncio
async def test_on_event_change_agent_state_action(mock_agent, mock_event_stream):
    controller = AgentController(
        agent=mock_agent,
        event_stream=mock_event_stream,
        max_iterations=10,
        sid='test',
        confirmation_mode=False,
        headless_mode=True,
    )
    controller.state.agent_state = AgentState.RUNNING
    change_state_action = ChangeAgentStateAction(agent_state=AgentState.PAUSED)
    await send_event_to_controller(controller, change_state_action)
    assert controller.get_agent_state() == AgentState.PAUSED
    await controller.close()


@pytest.mark.asyncio
async def test_react_to_exception(mock_agent, mock_event_stream, mock_status_callback):
    controller = AgentController(
        agent=mock_agent,
        event_stream=mock_event_stream,
        status_callback=mock_status_callback,
        max_iterations=10,
        sid='test',
        confirmation_mode=False,
        headless_mode=True,
    )
    error_message = 'Test error'
    await controller._react_to_exception(RuntimeError(error_message))
    controller.status_callback.assert_called_once()
    await controller.close()


@pytest.mark.asyncio
async def test_run_controller_with_fatal_error():
    config = AppConfig()
    file_store = InMemoryFileStore({})
    event_stream = EventStream(sid='test', file_store=file_store)

    agent = MagicMock(spec=Agent)
    agent = MagicMock(spec=Agent)

    def agent_step_fn(state):
        print(f'agent_step_fn received state: {state}')
        return CmdRunAction(command='ls')

    agent.step = agent_step_fn
    agent.llm = MagicMock(spec=LLM)
    agent.llm.metrics = Metrics()
    agent.llm.config = config.get_llm_config()

    runtime = MagicMock(spec=Runtime)

    def on_event(event: Event):
        if isinstance(event, CmdRunAction):
            error_obs = ErrorObservation('You messed around with Jim')
            error_obs._cause = event.id
            event_stream.add_event(error_obs, EventSource.USER)

    event_stream.subscribe(EventStreamSubscriber.RUNTIME, on_event, str(uuid4()))
    runtime.event_stream = event_stream

    state = await run_controller(
        config=config,
        initial_user_action=MessageAction(content='Test message'),
        runtime=runtime,
        sid='test',
        agent=agent,
        fake_user_response_fn=lambda _: 'repeat',
    )
    print(f'state: {state}')
    events = list(event_stream.get_events())
    print(f'event_stream: {events}')
    assert state.iteration == 4
    assert state.agent_state == AgentState.ERROR
    assert state.last_error == 'AgentStuckInLoopError: Agent got stuck in a loop'
    assert len(events) == 11


@pytest.mark.asyncio
async def test_run_controller_stop_with_stuck():
    config = AppConfig()
    file_store = InMemoryFileStore({})
    event_stream = EventStream(sid='test', file_store=file_store)

    agent = MagicMock(spec=Agent)

    def agent_step_fn(state):
        print(f'agent_step_fn received state: {state}')
        return CmdRunAction(command='ls')

    agent.step = agent_step_fn
    agent.llm = MagicMock(spec=LLM)
    agent.llm.metrics = Metrics()
    agent.llm.config = config.get_llm_config()
    runtime = MagicMock(spec=Runtime)

    def on_event(event: Event):
        if isinstance(event, CmdRunAction):
            non_fatal_error_obs = ErrorObservation(
                'Non fatal error here to trigger loop'
            )
            non_fatal_error_obs._cause = event.id
            event_stream.add_event(non_fatal_error_obs, EventSource.ENVIRONMENT)

    event_stream.subscribe(EventStreamSubscriber.RUNTIME, on_event, str(uuid4()))
    runtime.event_stream = event_stream

    state = await run_controller(
        config=config,
        initial_user_action=MessageAction(content='Test message'),
        runtime=runtime,
        sid='test',
        agent=agent,
        fake_user_response_fn=lambda _: 'repeat',
    )
    events = list(event_stream.get_events())
    print(f'state: {state}')
    for i, event in enumerate(events):
        print(f'event {i}: {event_to_dict(event)}')

    assert state.iteration == 4
    assert len(events) == 11
    # check the eventstream have 4 pairs of repeated actions and observations
    repeating_actions_and_observations = events[2:10]
    for action, observation in zip(
        repeating_actions_and_observations[0::2],
        repeating_actions_and_observations[1::2],
    ):
        action_dict = event_to_dict(action)
        observation_dict = event_to_dict(observation)
        assert action_dict['action'] == 'run' and action_dict['args']['command'] == 'ls'
        assert (
            observation_dict['observation'] == 'error'
            and observation_dict['content'] == 'Non fatal error here to trigger loop'
        )
    last_event = event_to_dict(events[-1])
    assert last_event['extras']['agent_state'] == 'error'
    assert last_event['observation'] == 'agent_state_changed'

    assert state.agent_state == AgentState.ERROR
    assert state.last_error == 'AgentStuckInLoopError: Agent got stuck in a loop'


@pytest.mark.asyncio
async def test_max_iterations_extension(mock_agent, mock_event_stream):
    # Test with headless_mode=False - should extend max_iterations
    initial_state = State(max_iterations=10)

    controller = AgentController(
        agent=mock_agent,
        event_stream=mock_event_stream,
        max_iterations=10,
        sid='test',
        confirmation_mode=False,
        headless_mode=False,
        initial_state=initial_state,
    )
    controller.state.agent_state = AgentState.RUNNING
    controller.state.iteration = 10
    assert controller.state.traffic_control_state == TrafficControlState.NORMAL

    # Trigger throttling by calling _step() when we hit max_iterations
    await controller._step()
    assert controller.state.traffic_control_state == TrafficControlState.THROTTLING
    assert controller.state.agent_state == AgentState.ERROR

    # Simulate a new user message
    message_action = MessageAction(content='Test message')
    message_action._source = EventSource.USER
    await send_event_to_controller(controller, message_action)

    # Max iterations should be extended to current iteration + initial max_iterations
    assert (
        controller.state.max_iterations == 20
    )  # Current iteration (10 initial because _step() should not have been executed) + initial max_iterations (10)
    assert controller.state.traffic_control_state == TrafficControlState.NORMAL
    assert controller.state.agent_state == AgentState.RUNNING

    # Close the controller to clean up
    await controller.close()

    # Test with headless_mode=True - should NOT extend max_iterations
    initial_state = State(max_iterations=10)
    controller = AgentController(
        agent=mock_agent,
        event_stream=mock_event_stream,
        max_iterations=10,
        sid='test',
        confirmation_mode=False,
        headless_mode=True,
        initial_state=initial_state,
    )
    controller.state.agent_state = AgentState.RUNNING
    controller.state.iteration = 10
    assert controller.state.traffic_control_state == TrafficControlState.NORMAL

    # Simulate a new user message
    message_action = MessageAction(content='Test message')
    message_action._source = EventSource.USER
    await send_event_to_controller(controller, message_action)

    # Max iterations should NOT be extended in headless mode
    assert controller.state.max_iterations == 10  # Original value unchanged

    # Trigger throttling by calling _step() when we hit max_iterations
    await controller._step()

    assert controller.state.traffic_control_state == TrafficControlState.THROTTLING
    assert controller.state.agent_state == AgentState.ERROR
    await controller.close()


@pytest.mark.asyncio
async def test_step_max_budget(mock_agent, mock_event_stream):
    controller = AgentController(
        agent=mock_agent,
        event_stream=mock_event_stream,
        max_iterations=10,
        max_budget_per_task=10,
        sid='test',
        confirmation_mode=False,
        headless_mode=False,
    )
    controller.state.agent_state = AgentState.RUNNING
    controller.state.metrics.accumulated_cost = 10.1
    assert controller.state.traffic_control_state == TrafficControlState.NORMAL
    await controller._step()
    assert controller.state.traffic_control_state == TrafficControlState.THROTTLING
    assert controller.state.agent_state == AgentState.ERROR
    await controller.close()


@pytest.mark.asyncio
async def test_step_max_budget_headless(mock_agent, mock_event_stream):
    controller = AgentController(
        agent=mock_agent,
        event_stream=mock_event_stream,
        max_iterations=10,
        max_budget_per_task=10,
        sid='test',
        confirmation_mode=False,
        headless_mode=True,
    )
    controller.state.agent_state = AgentState.RUNNING
    controller.state.metrics.accumulated_cost = 10.1
    assert controller.state.traffic_control_state == TrafficControlState.NORMAL
    await controller._step()
    assert controller.state.traffic_control_state == TrafficControlState.THROTTLING
    # In headless mode, throttling results in an error
    assert controller.state.agent_state == AgentState.ERROR
    await controller.close()


@pytest.mark.asyncio
async def test_reset_with_pending_action_no_observation(mock_agent, mock_event_stream):
    """Test reset() when there's a pending action with tool call metadata but no observation."""
    controller = AgentController(
        agent=mock_agent,
        event_stream=mock_event_stream,
        max_iterations=10,
        sid='test',
        confirmation_mode=False,
        headless_mode=True,
    )

    # Create a pending action with tool call metadata
    pending_action = CmdRunAction(command='test')
    pending_action.tool_call_metadata = {
        'function': 'test_function',
        'args': {'arg1': 'value1'},
    }
    controller._pending_action = pending_action

    # Call reset
    controller._reset()

    # Verify that an ErrorObservation was added to the event stream
    mock_event_stream.add_event.assert_called_once()
    args, kwargs = mock_event_stream.add_event.call_args
    error_obs, source = args
    assert isinstance(error_obs, ErrorObservation)
    assert error_obs.content == 'The action has not been executed.'
    assert error_obs.tool_call_metadata == pending_action.tool_call_metadata
    assert error_obs._cause == pending_action.id
    assert source == EventSource.AGENT

    # Verify that pending action was reset
    assert controller._pending_action is None

    # Verify that agent.reset() was called
    mock_agent.reset.assert_called_once()
    await controller.close()


@pytest.mark.asyncio
async def test_reset_with_pending_action_existing_observation(
    mock_agent, mock_event_stream
):
    """Test reset() when there's a pending action with tool call metadata and an existing observation."""
    controller = AgentController(
        agent=mock_agent,
        event_stream=mock_event_stream,
        max_iterations=10,
        sid='test',
        confirmation_mode=False,
        headless_mode=True,
    )

    # Create a pending action with tool call metadata
    pending_action = CmdRunAction(command='test')
    pending_action.tool_call_metadata = {
        'function': 'test_function',
        'args': {'arg1': 'value1'},
    }
    controller._pending_action = pending_action

    # Add an existing observation to the history
    existing_obs = ErrorObservation(content='Previous error')
    existing_obs.tool_call_metadata = pending_action.tool_call_metadata
    controller.state.history.append(existing_obs)

    # Call reset
    controller._reset()

    # Verify that no new ErrorObservation was added to the event stream
    mock_event_stream.add_event.assert_not_called()

    # Verify that pending action was reset
    assert controller._pending_action is None

    # Verify that agent.reset() was called
    mock_agent.reset.assert_called_once()
    await controller.close()


@pytest.mark.asyncio
async def test_reset_without_pending_action(mock_agent, mock_event_stream):
    """Test reset() when there's no pending action."""
    controller = AgentController(
        agent=mock_agent,
        event_stream=mock_event_stream,
        max_iterations=10,
        sid='test',
        confirmation_mode=False,
        headless_mode=True,
    )

    # Call reset
    controller._reset()

    # Verify that no ErrorObservation was added to the event stream
    mock_event_stream.add_event.assert_not_called()

    # Verify that pending action is None
    assert controller._pending_action is None

    # Verify that agent.reset() was called
    mock_agent.reset.assert_called_once()
    await controller.close()


@pytest.mark.asyncio
async def test_reset_with_pending_action_no_metadata(
    mock_agent, mock_event_stream, monkeypatch
):
    """Test reset() when there's a pending action without tool call metadata."""
    controller = AgentController(
        agent=mock_agent,
        event_stream=mock_event_stream,
        max_iterations=10,
        sid='test',
        confirmation_mode=False,
        headless_mode=True,
    )

    # Create a pending action without tool call metadata
    pending_action = CmdRunAction(command='test')
    # Mock hasattr to return False for tool_call_metadata
    original_hasattr = hasattr

    def mock_hasattr(obj, name):
        if obj == pending_action and name == 'tool_call_metadata':
            return False
        return original_hasattr(obj, name)

    monkeypatch.setattr('builtins.hasattr', mock_hasattr)
    controller._pending_action = pending_action

    # Call reset
    controller._reset()

    # Verify that no ErrorObservation was added to the event stream
    mock_event_stream.add_event.assert_not_called()

    # Verify that pending action was reset
    assert controller._pending_action is None

    # Verify that agent.reset() was called
    mock_agent.reset.assert_called_once()
    await controller.close()


@pytest.mark.asyncio
async def test_run_controller_max_iterations_has_metrics():
    config = AppConfig(
        max_iterations=3,
    )
    file_store = InMemoryFileStore({})
    event_stream = EventStream(sid='test', file_store=file_store)

    agent = MagicMock(spec=Agent)
    agent.llm = MagicMock(spec=LLM)
    agent.llm.metrics = Metrics()
    agent.llm.config = config.get_llm_config()

    def agent_step_fn(state):
        print(f'agent_step_fn received state: {state}')
        # Mock the cost of the LLM
        agent.llm.metrics.add_cost(10.0)
        print(
            f'agent.llm.metrics.accumulated_cost: {agent.llm.metrics.accumulated_cost}'
        )
        return CmdRunAction(command='ls')

    agent.step = agent_step_fn

    runtime = MagicMock(spec=Runtime)

    def on_event(event: Event):
        if isinstance(event, CmdRunAction):
            non_fatal_error_obs = ErrorObservation(
                'Non fatal error. event id: ' + str(event.id)
            )
            non_fatal_error_obs._cause = event.id
            event_stream.add_event(non_fatal_error_obs, EventSource.ENVIRONMENT)

    event_stream.subscribe(EventStreamSubscriber.RUNTIME, on_event, str(uuid4()))
    runtime.event_stream = event_stream

    state = await run_controller(
        config=config,
        initial_user_action=MessageAction(content='Test message'),
        runtime=runtime,
        sid='test',
        agent=agent,
        fake_user_response_fn=lambda _: 'repeat',
    )
    assert state.iteration == 3
    assert state.agent_state == AgentState.ERROR
    assert (
        state.last_error
        == 'RuntimeError: Agent reached maximum iteration in headless mode. Current iteration: 3, max iteration: 3'
    )
    assert (
        state.metrics.accumulated_cost == 10.0 * 3
    ), f'Expected accumulated cost to be 30.0, but got {state.metrics.accumulated_cost}'