import asyncio
import json
from collections.abc import AsyncIterator
from dataclasses import dataclass
from typing import Any

import pytest

from agent_lab.application.contracts import AgentParams, DebugRunRequest, EventAgentParams
from agent_lab.application.runtime import DebugRuntime
from agent_lab.application.tools import build_default_tool_registry
from agent_lab.domain.events import ToolCallEvent
from agent_lab.domain.messages import ChatMessage, StreamItem


MODES = ("dual_agent", "chat_agent_tools")
SCENARIOS = (
    "ordinary_chat",
    "device_volume_silent",
    "calendar_schedule_template",
    "web_search_two_answers",
    "session_terminate",
    "parallel_volume_schedule",
)
BUILTIN_EVENT_NAMES = (
    "session.terminate",
    "device.volume.adjust",
    "calendar.schedule.create",
    "knowledge.web.search",
)
SCHEDULE_ARGUMENTS = {
    "title": "Design review",
    "start_at": "2026-07-14T09:30:00+08:00",
    "timezone": "Asia/Shanghai",
}
SCHEDULE_CONFIRMATION = (
    "Scheduled Design review for 2026-07-14T09:30:00+08:00 "
    "(Asia/Shanghai)."
)


@dataclass(frozen=True)
class ExpectedSemantics:
    visible_messages: tuple[str, ...]
    tool_names: tuple[str, ...]
    model_calls: int
    terminal_count: int = 0


EXPECTED = {
    "ordinary_chat": ExpectedSemantics(("Ordinary answer.",), (), 1),
    "device_volume_silent": ExpectedSemantics(
        (),
        ("device.volume.adjust",),
        1,
    ),
    "calendar_schedule_template": ExpectedSemantics(
        (SCHEDULE_CONFIRMATION,),
        ("calendar.schedule.create",),
        1,
    ),
    "web_search_two_answers": ExpectedSemantics(
        ("I will check.", "Grounded search update."),
        ("knowledge.web.search",),
        2,
    ),
    "session_terminate": ExpectedSemantics(
        ("Goodbye.",),
        ("session.terminate",),
        1,
        terminal_count=1,
    ),
    "parallel_volume_schedule": ExpectedSemantics(
        (SCHEDULE_CONFIRMATION,),
        ("device.volume.adjust", "calendar.schedule.create"),
        1,
    ),
}


class ScriptedChatClient:
    def __init__(self, rounds: list[list[StreamItem]]) -> None:
        self.rounds = rounds
        self.calls = 0

    async def stream_chat(
        self,
        messages: list[ChatMessage],
        tools: list[dict[str, Any]],
        params: AgentParams,
        tool_choice: dict[str, Any] | None = None,
    ) -> AsyncIterator[StreamItem]:
        del messages, tools, params, tool_choice
        items = self.rounds[self.calls]
        self.calls += 1
        for item in items:
            yield item


class RecordingPorts:
    def __init__(self, *, parallel_barrier: bool = False) -> None:
        self.parallel_barrier = parallel_barrier
        self.session_calls: list[tuple[str, str | None]] = []
        self.volume_calls: list[tuple[str, str, int | None, int | None]] = []
        self.calendar_calls: list[
            tuple[str, str, str, str, str | None, int | None]
        ] = []
        self.search_calls: list[tuple[str, str, int]] = []
        self.started: set[str] = set()
        self.both_started = asyncio.Event()
        self.volume_release = asyncio.Event()
        self.schedule_release = asyncio.Event()
        self.schedule_finished = asyncio.Event()
        if not parallel_barrier:
            self.volume_release.set()
            self.schedule_release.set()

    async def terminate(
        self,
        event_id: str,
        *,
        reason: str | None = None,
    ) -> dict[str, Any]:
        self.session_calls.append((event_id, reason))
        return {
            "tool": "session.terminate",
            "status": "terminated",
            "event_id": event_id,
            "reason": reason,
        }

    async def adjust(
        self,
        event_id: str,
        *,
        mode: str,
        value: int | None = None,
        delta: int | None = None,
    ) -> dict[str, Any]:
        self.volume_calls.append((event_id, mode, value, delta))
        await self._wait_at_barrier("volume", self.volume_release)
        payload: dict[str, Any] = {
            "tool": "device.volume.adjust",
            "status": "applied",
            "event_id": event_id,
            "mode": mode,
        }
        if value is not None:
            payload["value"] = value
        if delta is not None:
            payload["delta"] = delta
        return payload

    async def create(
        self,
        event_id: str,
        *,
        title: str,
        start_at: str,
        timezone: str,
        recurrence: str | None = None,
        reminder_minutes: int | None = None,
    ) -> dict[str, Any]:
        self.calendar_calls.append(
            (
                event_id,
                title,
                start_at,
                timezone,
                recurrence,
                reminder_minutes,
            )
        )
        await self._wait_at_barrier("schedule", self.schedule_release)
        self.schedule_finished.set()
        return {
            "tool": "calendar.schedule.create",
            "status": "created",
            "event_id": event_id,
            "schedule": {
                "title": title,
                "start_at": start_at,
                "timezone": timezone,
            },
        }

    async def search(
        self,
        event_id: str,
        *,
        query: str,
        max_results: int = 3,
    ) -> dict[str, Any]:
        self.search_calls.append((event_id, query, max_results))
        return {
            "tool": "knowledge.web.search",
            "query": query,
            "sources": [
                {
                    "title": "Matrix source",
                    "url": "https://example.invalid/matrix",
                    "snippet": f"Deterministic context for: {query}",
                }
            ],
            "retrieved_at": "2026-07-13T00:00:00Z",
        }

    async def _wait_at_barrier(
        self,
        name: str,
        release: asyncio.Event,
    ) -> None:
        if not self.parallel_barrier:
            return
        self.started.add(name)
        if len(self.started) == 2:
            self.both_started.set()
        await release.wait()


def _event(call_id: str, name: str, arguments: dict[str, Any]) -> ToolCallEvent:
    return ToolCallEvent(
        id=call_id,
        name=name,
        arguments=arguments,
        raw_arguments=json.dumps(arguments, sort_keys=True, separators=(",", ":")),
    )


def _event_item(mode: str, event: ToolCallEvent) -> StreamItem:
    if mode == "dual_agent":
        return StreamItem.text_event(event)
    return StreamItem.provider_tool_call(event)


def _scenario_setup(
    mode: str,
    scenario: str,
) -> tuple[DebugRunRequest, list[list[StreamItem]]]:
    if scenario == "ordinary_chat":
        user_message = "Hello."
        enabled_tools = list(BUILTIN_EVENT_NAMES)
        rounds = [[StreamItem.message_delta("Ordinary answer.")]]
    elif scenario == "device_volume_silent":
        user_message = "set volume to 30"
        enabled_tools = ["device.volume.adjust"]
        rounds = [
            [
                _event_item(
                    mode,
                    _event(
                        "volume-1",
                        "device.volume.adjust",
                        {"mode": "absolute", "value": 30},
                    ),
                )
            ]
        ]
    elif scenario == "calendar_schedule_template":
        user_message = (
            'schedule "Design review" at 2026-07-14T09:30:00+08:00 '
            "timezone Asia/Shanghai"
        )
        enabled_tools = ["calendar.schedule.create"]
        rounds = [
            [
                _event_item(
                    mode,
                    _event(
                        "schedule-1",
                        "calendar.schedule.create",
                        SCHEDULE_ARGUMENTS,
                    ),
                )
            ]
        ]
    elif scenario == "web_search_two_answers":
        user_message = "event batch safety"
        enabled_tools = ["knowledge.web.search"]
        rounds = [
            [
                StreamItem.message_delta("I will check."),
                _event_item(
                    mode,
                    _event(
                        "search-1",
                        "knowledge.web.search",
                        {"query": user_message},
                    ),
                ),
            ],
            [StreamItem.message_delta("Grounded search update.")],
        ]
    elif scenario == "session_terminate":
        user_message = "end this session"
        enabled_tools = ["session.terminate"]
        rounds = [
            [
                _event_item(
                    mode,
                    _event("terminate-1", "session.terminate", {}),
                )
            ]
        ]
    elif scenario == "parallel_volume_schedule":
        user_message = (
            'set volume to 30 and schedule "Design review" at '
            "2026-07-14T09:30:00+08:00 timezone Asia/Shanghai"
        )
        enabled_tools = ["device.volume.adjust", "calendar.schedule.create"]
        rounds = [
            [
                _event_item(
                    mode,
                    _event(
                        "parallel-volume",
                        "device.volume.adjust",
                        {"mode": "absolute", "value": 30},
                    ),
                ),
                _event_item(
                    mode,
                    _event(
                        "parallel-schedule",
                        "calendar.schedule.create",
                        SCHEDULE_ARGUMENTS,
                    ),
                ),
            ]
        ]
    else:
        raise AssertionError(f"unknown comparison scenario: {scenario}")

    request = DebugRunRequest(
        user_message=user_message,
        system_prompts=["Exercise the requested business scenario."],
        pre_messages=[],
        chat_agent=AgentParams(
            model="comparison-model",
            temperature=0.0,
            max_tokens=128,
        ),
        event_agent=EventAgentParams(
            model="comparison-model",
            temperature=0.0,
            max_tokens=128,
            enabled_tools=enabled_tools,
            max_event_loops=1,
            max_parallel_events=2,
            batch_timeout_seconds=1.0,
        ),
        tool_invocation_mode=mode,
    )
    return request, rounds


async def _collect_outputs(
    stream: AsyncIterator[dict[str, Any]],
) -> list[dict[str, Any]]:
    return [message async for message in stream]


def _tool_payloads(outputs: list[dict[str, Any]]) -> list[dict[str, Any]]:
    return [
        json.loads(message["message"]["content"])
        for message in outputs
        if message["type"] == "tool_result"
    ]


def _assert_port_calls(scenario: str, ports: RecordingPorts) -> None:
    expected_session: list[tuple[str, str | None]] = []
    expected_volume: list[tuple[str, str, int | None, int | None]] = []
    expected_calendar: list[
        tuple[str, str, str, str, str | None, int | None]
    ] = []
    expected_search: list[tuple[str, str, int]] = []

    if scenario == "device_volume_silent":
        expected_volume = [("volume-1", "absolute", 30, None)]
    elif scenario == "calendar_schedule_template":
        expected_calendar = [
            (
                "schedule-1",
                "Design review",
                "2026-07-14T09:30:00+08:00",
                "Asia/Shanghai",
                None,
                None,
            )
        ]
    elif scenario == "web_search_two_answers":
        expected_search = [("search-1", "event batch safety", 3)]
    elif scenario == "session_terminate":
        expected_session = [("terminate-1", None)]
    elif scenario == "parallel_volume_schedule":
        expected_volume = [("parallel-volume", "absolute", 30, None)]
        expected_calendar = [
            (
                "parallel-schedule",
                "Design review",
                "2026-07-14T09:30:00+08:00",
                "Asia/Shanghai",
                None,
                None,
            )
        ]

    assert ports.session_calls == expected_session
    assert ports.volume_calls == expected_volume
    assert ports.calendar_calls == expected_calendar
    assert ports.search_calls == expected_search


@pytest.mark.asyncio
@pytest.mark.parametrize("mode", MODES)
@pytest.mark.parametrize("scenario", SCENARIOS)
async def test_invocation_modes_share_business_semantics(
    mode: str,
    scenario: str,
) -> None:
    request, rounds = _scenario_setup(mode, scenario)
    ports = RecordingPorts(parallel_barrier=scenario == "parallel_volume_schedule")
    registry = build_default_tool_registry(
        session_termination_port=ports,
        device_volume_port=ports,
        calendar_schedule_port=ports,
        web_search_port=ports,
    )
    client = ScriptedChatClient(rounds)
    run_task = asyncio.create_task(
        _collect_outputs(DebugRuntime(client, registry=registry).run(request))
    )

    try:
        if scenario == "parallel_volume_schedule":
            await asyncio.wait_for(ports.both_started.wait(), timeout=1)
            assert ports.started == {"volume", "schedule"}
            ports.schedule_release.set()
            await asyncio.wait_for(ports.schedule_finished.wait(), timeout=1)
            assert not run_task.done()
            ports.volume_release.set()
        outputs = await asyncio.wait_for(run_task, timeout=2)
    finally:
        ports.schedule_release.set()
        ports.volume_release.set()
        if not run_task.done():
            run_task.cancel()
            await asyncio.gather(run_task, return_exceptions=True)

    expected = EXPECTED[scenario]
    visible_messages = tuple(
        message["content"]
        for message in outputs
        if message["type"] == "message_delta"
    )
    tool_payloads = _tool_payloads(outputs)
    terminal_count = sum(
        message.get("event") == "terminal_completed" for message in outputs
    )

    assert visible_messages == expected.visible_messages
    assert tuple(payload["tool"] for payload in tool_payloads) == expected.tool_names
    assert client.calls == expected.model_calls
    assert terminal_count == expected.terminal_count
    assert outputs[-1] == {"type": "done"}
    _assert_port_calls(scenario, ports)

    if scenario == "web_search_two_answers":
        assert tool_payloads[0]["sources"][0]["title"] == "Matrix source"
        business = [message for message in outputs if message["type"] != "audit"]
        visible_indexes = [
            index
            for index, message in enumerate(business)
            if message["type"] == "message_delta"
        ]
        tool_index = next(
            index
            for index, message in enumerate(business)
            if message["type"] == "tool_result"
        )
        assert visible_indexes[0] < tool_index < visible_indexes[1]