"""Tests for /restart slash command."""

from __future__ import annotations

import asyncio
import os
import time
from types import SimpleNamespace
from unittest.mock import AsyncMock, MagicMock, patch

import pytest

from nanobot.bus.events import InboundMessage, OutboundMessage
from nanobot.providers.base import LLMResponse


def _make_loop():
    """Create a minimal AgentLoop with mocked dependencies."""
    from nanobot.agent.loop import AgentLoop
    from nanobot.bus.queue import MessageBus

    bus = MessageBus()
    provider = MagicMock()
    provider.get_default_model.return_value = "test-model"
    workspace = MagicMock()
    workspace.__truediv__ = MagicMock(return_value=MagicMock())

    with patch("nanobot.agent.loop.ContextBuilder"), \
         patch("nanobot.agent.loop.SessionManager"), \
         patch("nanobot.agent.loop.SubagentManager"):
        loop = AgentLoop(bus=bus, provider=provider, workspace=workspace)
    return loop, bus


async def _wait_until(predicate, *, timeout: float = 0.2, interval: float = 0.01) -> None:
    deadline = time.monotonic() + timeout
    while time.monotonic() < deadline:
        if predicate():
            return
        await asyncio.sleep(interval)
    assert predicate()


class TestRestartCommand:

    @pytest.mark.asyncio
    async def test_restart_sends_message_and_calls_execv(self):
        from nanobot.command.builtin import cmd_restart
        from nanobot.command.router import CommandContext
        from nanobot.utils.restart import (
            RESTART_NOTIFY_CHANNEL_ENV,
            RESTART_NOTIFY_CHAT_ID_ENV,
            RESTART_STARTED_AT_ENV,
        )

        loop, bus = _make_loop()
        msg = InboundMessage(channel="cli", sender_id="user", chat_id="direct", content="/restart")
        ctx = CommandContext(msg=msg, session=None, key=msg.session_key, raw="/restart", loop=loop)

        async def _fast_sleep(_delay: float) -> None:
            return None

        scheduled: list[asyncio.Task] = []

        def _capture_task(coro):
            task = asyncio.create_task(coro)
            scheduled.append(task)
            return task

        fake_asyncio = SimpleNamespace(
            sleep=_fast_sleep,
            create_task=_capture_task,
        )

        with patch.dict(os.environ, {}, clear=False), \
             patch("nanobot.command.builtin.asyncio", new=fake_asyncio), \
             patch("nanobot.command.builtin.os.execv") as mock_execv:
            out = await cmd_restart(ctx)
            assert "Restarting" in out.content
            assert os.environ.get(RESTART_NOTIFY_CHANNEL_ENV) == "cli"
            assert os.environ.get(RESTART_NOTIFY_CHAT_ID_ENV) == "direct"
            assert os.environ.get(RESTART_STARTED_AT_ENV)

            assert scheduled
            await scheduled[0]
            mock_execv.assert_called_once()

    @pytest.mark.asyncio
    async def test_restart_intercepted_in_run_loop(self):
        """Verify /restart is handled at the run-loop level, not inside _dispatch."""
        loop, bus = _make_loop()
        msg = InboundMessage(channel="telegram", sender_id="u1", chat_id="c1", content="/restart")

        with patch.object(loop, "_dispatch", new_callable=AsyncMock) as mock_dispatch, \
             patch("nanobot.command.builtin.os.execv"):
            await bus.publish_inbound(msg)

            loop._running = True
            run_task = asyncio.create_task(loop.run())
            await asyncio.sleep(0.1)
            loop._running = False
            run_task.cancel()
            try:
                await run_task
            except asyncio.CancelledError:
                pass

            mock_dispatch.assert_not_called()
            out = await asyncio.wait_for(bus.consume_outbound(), timeout=1.0)
            assert "Restarting" in out.content

    @pytest.mark.asyncio
    async def test_status_intercepted_in_run_loop(self):
        """Verify /status is handled at the run-loop level for immediate replies."""
        loop, bus = _make_loop()
        msg = InboundMessage(channel="telegram", sender_id="u1", chat_id="c1", content="/status")

        with patch.object(loop, "_dispatch", new_callable=AsyncMock) as mock_dispatch:
            await bus.publish_inbound(msg)

            loop._running = True
            run_task = asyncio.create_task(loop.run())
            await asyncio.sleep(0.1)
            loop._running = False
            run_task.cancel()
            try:
                await run_task
            except asyncio.CancelledError:
                pass

            mock_dispatch.assert_not_called()
            out = await asyncio.wait_for(bus.consume_outbound(), timeout=1.0)
            assert "nanobot" in out.content.lower() or "Model" in out.content

    @pytest.mark.asyncio
    async def test_run_propagates_external_cancellation(self):
        """External task cancellation should not be swallowed by the inbound wait loop."""
        loop, _bus = _make_loop()

        run_task = asyncio.create_task(loop.run())
        await asyncio.sleep(0.1)
        run_task.cancel()

        with pytest.raises(asyncio.CancelledError):
            await asyncio.wait_for(run_task, timeout=1.0)

    @pytest.mark.asyncio
    async def test_help_includes_restart(self):
        loop, bus = _make_loop()
        msg = InboundMessage(channel="telegram", sender_id="u1", chat_id="c1", content="/help")

        response = await loop._process_message(msg)

        assert response is not None
        assert "/restart" in response.content
        assert "/status" in response.content
        assert response.metadata == {"render_as": "text"}

    @pytest.mark.asyncio
    async def test_status_reports_runtime_info(self):
        loop, _bus = _make_loop()
        session = MagicMock()
        session.get_history.return_value = [{"role": "user"}] * 3
        loop.sessions.get_or_create.return_value = session
        loop._start_time = time.time() - 125
        loop._last_usage = {"prompt_tokens": 0, "completion_tokens": 0}
        loop.consolidator.estimate_session_prompt_tokens = MagicMock(
            return_value=(20500, "tiktoken")
        )
        loop.subagents.get_running_count_by_session.return_value = 0

        msg = InboundMessage(channel="telegram", sender_id="u1", chat_id="c1", content="/status")

        response = await loop._process_message(msg)

        assert response is not None
        assert "Model: test-model" in response.content
        assert "Tokens: 0 in / 0 out" in response.content
        assert "Context: 20k/65k (31% of input budget)" in response.content
        assert "Session: 3 messages" in response.content
        assert "Uptime: 2m 5s" in response.content
        assert "Tasks: 0 active" in response.content
        assert response.metadata == {"render_as": "text"}

    @pytest.mark.asyncio
    async def test_status_counts_running_dispatch_and_subagent_tasks(self):
        loop, _bus = _make_loop()
        session = MagicMock()
        session.get_history.return_value = [{"role": "user"}]
        loop.sessions.get_or_create.return_value = session
        loop.consolidator.estimate_session_prompt_tokens = MagicMock(
            return_value=(1000, "tiktoken")
        )

        running_task = MagicMock()
        running_task.done.return_value = False
        finished_task = MagicMock()
        finished_task.done.return_value = True

        msg = InboundMessage(channel="telegram", sender_id="u1", chat_id="c1", content="/status")
        loop._active_tasks[msg.session_key] = [running_task, finished_task]
        loop.subagents.get_running_count_by_session.return_value = 2

        response = await loop._process_message(msg)

        assert response is not None
        assert "Tasks: 3 active" in response.content

    @pytest.mark.asyncio
    async def test_run_agent_loop_resets_usage_when_provider_omits_it(self):
        loop, _bus = _make_loop()
        loop.provider.chat_with_retry = AsyncMock(side_effect=[
            LLMResponse(content="first", usage={"prompt_tokens": 9, "completion_tokens": 4}),
            LLMResponse(content="second", usage={}),
        ])

        await loop._run_agent_loop([])
        assert loop._last_usage["prompt_tokens"] == 9
        assert loop._last_usage["completion_tokens"] == 4

        await loop._run_agent_loop([])
        assert loop._last_usage["prompt_tokens"] == 0
        assert loop._last_usage["completion_tokens"] == 0

    @pytest.mark.asyncio
    async def test_status_falls_back_to_last_usage_when_context_estimate_missing(self):
        loop, _bus = _make_loop()
        session = MagicMock()
        session.get_history.return_value = [{"role": "user"}]
        loop.sessions.get_or_create.return_value = session
        loop._last_usage = {"prompt_tokens": 1200, "completion_tokens": 34}
        loop.consolidator.estimate_session_prompt_tokens = MagicMock(
            return_value=(0, "none")
        )
        loop.subagents.get_running_count_by_session.return_value = 0

        response = await loop._process_message(
            InboundMessage(channel="telegram", sender_id="u1", chat_id="c1", content="/status")
        )

        assert response is not None
        assert "Tokens: 1200 in / 34 out" in response.content
        assert "Context: 1k/65k (1% of input budget)" in response.content
        assert "Tasks: 0 active" in response.content

    @pytest.mark.asyncio
    async def test_process_direct_preserves_render_metadata(self):
        loop, _bus = _make_loop()
        session = MagicMock()
        session.get_history.return_value = []
        loop.sessions.get_or_create.return_value = session
        loop.subagents.get_running_count.return_value = 0
        loop.subagents.get_running_count_by_session.return_value = 0

        response = await loop.process_direct("/status", session_key="cli:test")

        assert response is not None
        assert response.metadata == {"render_as": "text"}