from __future__ import annotations

import asyncio
import json
import os
import re
import time
from dataclasses import dataclass
from pathlib import Path
from urllib.parse import urlsplit, urlunsplit

import aiohttp
import structlog
from aiohttp import web
from dotenv import load_dotenv

from adapter.web.converter import json_to_incoming, outgoing_to_json
from adapter.web.store import WebSessionStore
from core.auth import AuthManager
from core.chat import ChatManager
from core.handler import EventDispatcher
from core.handlers import register_all
from core.protocol import IncomingCommand, IncomingMessage, OutgoingEvent, OutgoingMessage
from core.settings import SettingsManager
from core.store import InMemoryStore, StateStore
from sdk.interface import PlatformClient, PlatformError
from sdk.mock import MockPlatformClient

logger = structlog.get_logger(__name__)

load_dotenv(Path(__file__).resolve().parents[2] / ".env")

PLATFORM = "web"


@dataclass
class WebRuntime:
    platform: PlatformClient
    store: StateStore
    chat_mgr: ChatManager
    auth_mgr: AuthManager
    settings_mgr: SettingsManager
    dispatcher: EventDispatcher
    session_store: WebSessionStore
    workspace_dir: Path


def _agent_base_url_from_env() -> str:
    if base_url := os.environ.get("AGENT_BASE_URL"):
        return base_url
    if ws_url := os.environ.get("AGENT_WS_URL"):
        parsed = urlsplit(ws_url)
        path = re.sub(r"(?:/v1)?/agent_ws(?:/[^/]+)?/?$", "", parsed.path.rstrip("/"))
        return urlunsplit((parsed.scheme, parsed.netloc, path, "", ""))
    return "http://127.0.0.1:8000"


def _build_platform_from_env(*, store: StateStore, chat_mgr: ChatManager) -> PlatformClient:
    backend = os.environ.get("WEB_PLATFORM_BACKEND", "mock").strip().lower()
    if backend == "real":
        from sdk.prototype_state import PrototypeStateStore
        from sdk.real import RealPlatformClient

        prototype_state = PrototypeStateStore()
        base_url = _agent_base_url_from_env()
        return RealPlatformClient(
            agent_id="web-agent",
            agent_base_url=base_url,
            prototype_state=prototype_state,
            platform=PLATFORM,
        )
    return MockPlatformClient()


def build_runtime(
    platform: PlatformClient | None = None,
    store: StateStore | None = None,
) -> WebRuntime:
    store = store or InMemoryStore()
    session_store = WebSessionStore()
    workspace_dir = Path(os.environ.get("SURFACES_WORKSPACE_DIR", "/workspace"))
    chat_mgr = ChatManager(platform, store)
    platform = platform or _build_platform_from_env(store=store, chat_mgr=chat_mgr)
    chat_mgr = ChatManager(platform, store)
    auth_mgr = AuthManager(platform, store)
    settings_mgr = SettingsManager(platform, store)
    dispatcher = EventDispatcher(
        platform=platform, chat_mgr=chat_mgr, auth_mgr=auth_mgr, settings_mgr=settings_mgr
    )
    register_all(dispatcher)
    return WebRuntime(
        platform=platform,
        store=store,
        chat_mgr=chat_mgr,
        auth_mgr=auth_mgr,
        settings_mgr=settings_mgr,
        dispatcher=dispatcher,
        session_store=session_store,
        workspace_dir=workspace_dir,
    )


class WebBot:
    def __init__(self, runtime: WebRuntime) -> None:
        self.runtime = runtime
        self._connections: dict[str, web.WebSocketResponse] = {}

    async def handle_ws(self, request: web.Request) -> web.WebSocketResponse:
        ws = web.WebSocketResponse(max_msg_size=0)
        await ws.prepare(request)
        session_id = ""
        user_id = ""
        logger.info("web_ws_connected", peer=request.remote)

        try:
            async for msg in ws:
                if msg.type == aiohttp.WSMsgType.TEXT:
                    session_id, user_id = await self._on_text(ws, msg.data, session_id, user_id)
                elif msg.type == aiohttp.WSMsgType.BINARY:
                    await self._on_binary(ws, msg.data, session_id, user_id)
                elif msg.type == aiohttp.WSMsgType.ERROR:
                    logger.error("web_ws_error", error=ws.exception())
        except asyncio.CancelledError:
            pass
        finally:
            if user_id:
                self._connections.pop(user_id, None)
            logger.info("web_ws_disconnected", user_id=user_id, peer=request.remote)

        return ws

    async def _on_text(
        self,
        ws: web.WebSocketResponse,
        data: str,
        session_id: str,
        user_id: str,
    ) -> tuple[str, str]:
        try:
            payload = json.loads(data)
        except json.JSONDecodeError:
            await self._send(ws, json.dumps({"type": "error", "text": "Invalid JSON"}))
            return session_id, user_id

        msg_type = payload.get("type", "")

        if msg_type == "auth":
            session_token = payload.get("session_token", "")
            if session_token:
                uid = await self.runtime.session_store.get_user_id(session_token)
                if uid:
                    session_id = session_token
                    user_id = uid
                    self._connections[user_id] = ws
                    await self._send(
                        ws,
                        json.dumps(
                            {"type": "connected", "user_id": user_id, "session_token": session_id},
                            ensure_ascii=False,
                        ),
                    )
                    await self._send_history(ws, user_id)
                    return session_id, user_id

            session_id = await self.runtime.session_store.create_session(
                payload.get("display_name")
            )
            user_id = await self.runtime.session_store.get_user_id(session_id)
            self._connections[user_id] = ws
            await self._send(
                ws,
                json.dumps(
                    {"type": "connected", "user_id": user_id, "session_token": session_id},
                    ensure_ascii=False,
                ),
            )
            return session_id, user_id

        if not user_id:
            await self._send(ws, json.dumps({"type": "error", "text": "Not authenticated"}))
            return session_id, user_id

        try:
            incoming = json_to_incoming(payload)
        except Exception as exc:
            logger.warning("web_convert_error", error=str(exc))
            await self._send(ws, json.dumps(
                {"type": "error", "text": "Ошибка обработки сообщения"}, ensure_ascii=False,
            ))
            return session_id, user_id
        if incoming is None:
            await self._send(ws, json.dumps(
                {"type": "error", "text": "Неизвестный тип сообщения"}, ensure_ascii=False,
            ))
            return session_id, user_id

        now = time.time()
        user_text = payload.get("text", "")
        if not user_text and payload.get("type") == "command":
            cmd = payload.get("command", "")
            args = payload.get("args", [])
            user_text = f"/{cmd} {' '.join(args)}".strip()
        await self._save_message(user_id, {
            "type": "message",
            "chat_id": incoming.chat_id,
            "text": user_text,
            "from": "user",
            "timestamp": now,
            "attachments": getattr(incoming, "attachments", None),
        })

        # Handle chat-management commands at web surface level
        if isinstance(incoming, IncomingCommand):
            cmd = incoming.command
            chat_id = incoming.chat_id

            if cmd == "delete":
                # Delete chat history, name, and archive state
                for store_key in (
                    f"web_history:{user_id}:{chat_id}",
                    f"web_chat_name:{user_id}:{chat_id}",
                    f"web_chat_archived:{user_id}:{chat_id}",
                ):
                    await self.runtime.store.delete(store_key)
                await self._send(ws, outgoing_to_json(
                    OutgoingMessage(chat_id=chat_id, text=f"Чат {chat_id} удалён")
                ))
                return session_id, user_id

            if cmd == "archive":
                target = incoming.args[0] if incoming.args else chat_id
                await self.runtime.store.set(f"web_chat_archived:{user_id}:{target}", "1")
                await self._save_message(user_id, {
                    "type": "message", "chat_id": target,
                    "text": f"Чат {target} архивирован", "from": "agent",
                    "timestamp": time.time(),
                })
                await self._send(ws, outgoing_to_json(
                    OutgoingMessage(chat_id=target, text=f"Чат {target} архивирован")
                ))
                await self._send(ws, json.dumps({
                    "type": "chat_archived", "chat_id": target,
                }))
                return session_id, user_id

            if cmd == "unarchive":
                target = incoming.args[0] if incoming.args else chat_id
                await self.runtime.store.delete(f"web_chat_archived:{user_id}:{target}")
                await self._save_message(user_id, {
                    "type": "message", "chat_id": target,
                    "text": f"Чат {target} восстановлен из архива", "from": "agent",
                    "timestamp": time.time(),
                })
                await self._send(ws, outgoing_to_json(
                    OutgoingMessage(chat_id=target, text=f"Чат {target} восстановлен из архива")
                ))
                await self._send(ws, json.dumps({
                    "type": "chat_unarchived", "chat_id": target,
                }))
                return session_id, user_id

            if cmd == "new":
                # Generate next available chat_id
                existing = set()
                for key in await self.runtime.store.keys(f"web_history:{user_id}:"):
                    cid = key.rsplit(":", 1)[-1]
                    existing.add(cid)
                n = 1
                while f"C{n}" in existing:
                    n += 1
                new_id = f"C{n}"
                default_name = f"Чат {n}"
                await self.runtime.store.set(f"web_chat_name:{user_id}:{new_id}", default_name)
                await self._save_message(user_id, {
                    "type": "message", "chat_id": new_id,
                    "text": f"Создан новый чат {new_id}", "from": "agent",
                    "timestamp": time.time(),
                })
                await self._send(ws, outgoing_to_json(
                    OutgoingMessage(chat_id=new_id, text=f"Создан чат {new_id}")
                ))
                await self._send(ws, json.dumps({
                    "type": "chat_new", "chat_id": new_id,
                }))
                await self._send(ws, json.dumps({
                    "type": "chat_name", "chat_id": new_id, "name": default_name,
                }))
                return session_id, user_id

            if cmd == "chats":
                chat_list = []
                for key in await self.runtime.store.keys(f"web_history:{user_id}:"):
                    cid = key.rsplit(":", 1)[-1]
                    is_archived = await self.runtime.store.get(f"web_chat_archived:{user_id}:{cid}")
                    name = await self.runtime.store.get(f"web_chat_name:{user_id}:{cid}")
                    label = name or cid
                    if is_archived:
                        label += " (архив)"
                    chat_list.append(f"• {label}")
                text = "Ваши чаты:\n" + "\n".join(chat_list) if chat_list else "Нет чатов"
                await self._send(ws, outgoing_to_json(
                    OutgoingMessage(chat_id=chat_id, text=text)
                ))
                return session_id, user_id

            if cmd == "save":
                logger.info("web_cmd_save_entered", args=incoming.args, cmd=cmd)
                if not incoming.args:
                    await self._send(ws, outgoing_to_json(
                        OutgoingMessage(chat_id=chat_id, text="⚠ Укажите имя: /save <имя>")
                    ))
                    return session_id, user_id
                name = " ".join(incoming.args)
                sessions = await self.runtime.store.get(f"web_sessions:{user_id}") or []
                if any(s["name"] == name for s in sessions):
                    await self._send(ws, outgoing_to_json(
                        OutgoingMessage(chat_id=chat_id, text=f"⚠ Сессия «{name}» уже существует.")
                    ))
                    return session_id, user_id
                sessions.append({"name": name, "created_at": time.strftime("%Y-%m-%dT%H:%M:%S")})
                await self.runtime.store.set(f"web_sessions:{user_id}", sessions)
                await self._save_message(user_id, {
                    "type": "message", "chat_id": chat_id,
                    "text": f"💾 Сохраняю контекст как «{name}»...", "from": "agent",
                    "timestamp": time.time(),
                })
                await self._send(ws, outgoing_to_json(
                    OutgoingMessage(chat_id=chat_id, text=f"💾 Сохраняю контекст как «{name}»...")
                ))
                prompt = IncomingMessage(
                    user_id=user_id, platform=PLATFORM, chat_id=chat_id,
                    text=f"Summarize our conversation and save to /workspace/contexts/{name}.md. Reply only with: Saved: {name}",
                    attachments=[],
                )
                try:
                    outgoing = await self.runtime.dispatcher.dispatch(prompt)
                except PlatformError as exc:
                    logger.warning("web_save_dispatch_error", user_id=user_id, error=str(exc))
                    text = f"⚠ Ошибка сохранения: {exc}"
                    outgoing = [OutgoingMessage(chat_id=chat_id, text=text)]
                except Exception as exc:
                    logger.warning("web_save_dispatch_error", user_id=user_id, error=str(exc))
                    text = f"⚠ Ошибка сохранения: {exc}"
                    outgoing = [OutgoingMessage(chat_id=chat_id, text=text)]
                save_msg = next((o for o in outgoing if isinstance(o, OutgoingMessage)), None)
                save_text = save_msg.text if save_msg else f"✅ Сохранено: {name}"
                await self._save_message(user_id, {
                    "type": "message", "chat_id": chat_id,
                    "text": save_text, "from": "agent",
                    "timestamp": time.time(),
                })
                await self._send(ws, outgoing_to_json(
                    OutgoingMessage(chat_id=chat_id, text=save_text)
                ))
                return session_id, user_id

            if cmd == "load":
                sessions = await self.runtime.store.get(f"web_sessions:{user_id}") or []
                if not incoming.args:
                    if not sessions:
                        await self._send(ws, outgoing_to_json(
                            OutgoingMessage(chat_id=chat_id, text="Нет сохранённых сессий. Используй /save [имя].")
                        ))
                        return session_id, user_id
                    session_list = [{"name": s["name"], "created_at": s["created_at"][:10]} for s in sessions]
                    await self._send(ws, json.dumps({"type": "sessions", "sessions": session_list}))
                    return session_id, user_id
                name = " ".join(incoming.args)
                match = next((s for s in sessions if s["name"] == name), None) if sessions else None
                if not match:
                    await self._send(ws, outgoing_to_json(
                        OutgoingMessage(chat_id=chat_id, text=f"⚠ Сессия «{name}» не найдена.")
                    ))
                    return session_id, user_id
                await self.runtime.store.set(f"web_current_session:{user_id}", name)
                await self._save_message(user_id, {
                    "type": "message", "chat_id": chat_id,
                    "text": f"📂 Загружаю контекст «{name}»...", "from": "agent",
                    "timestamp": time.time(),
                })
                await self._send(ws, outgoing_to_json(
                    OutgoingMessage(chat_id=chat_id, text=f"📂 Загружаю контекст «{name}»...")
                ))
                prompt = IncomingMessage(
                    user_id=user_id, platform=PLATFORM, chat_id=chat_id,
                    text=f"Load context from /workspace/contexts/{name}.md and use it as background for our conversation. Reply: Loaded: {name}",
                    attachments=[],
                )
                try:
                    outgoing = await self.runtime.dispatcher.dispatch(prompt)
                except PlatformError as exc:
                    logger.warning("web_load_dispatch_error", user_id=user_id, error=str(exc))
                    text = f"⚠ Ошибка загрузки: {exc}"
                    outgoing = [OutgoingMessage(chat_id=chat_id, text=text)]
                except Exception as exc:
                    logger.warning("web_load_dispatch_error", user_id=user_id, error=str(exc))
                    text = f"⚠ Ошибка загрузки: {exc}"
                    outgoing = [OutgoingMessage(chat_id=chat_id, text=text)]
                load_msg = next((o for o in outgoing if isinstance(o, OutgoingMessage)), None)
                load_text = load_msg.text if load_msg else f"✅ Загружено: {name}"
                await self._save_message(user_id, {
                    "type": "message", "chat_id": chat_id,
                    "text": load_text, "from": "agent",
                    "timestamp": time.time(),
                })
                await self._send(ws, outgoing_to_json(
                    OutgoingMessage(chat_id=chat_id, text=load_text)
                ))
                return session_id, user_id

            if cmd == "context":
                sessions = await self.runtime.store.get(f"web_sessions:{user_id}") or []
                current = await self.runtime.store.get(f"web_current_session:{user_id}")
                lines = [f"Контекст чата: {chat_id}"]
                lines.append(f"Сессия: {current or 'не загружена'}")
                lines.append(f"Сохранения ({len(sessions)}):")
                for s in sessions:
                    lines.append(f"  - {s['name']} ({s['created_at'][:10]})")
                text = "\n".join(lines)
                await self._save_message(user_id, {
                    "type": "message", "chat_id": chat_id,
                    "text": text, "from": "agent",
                    "timestamp": time.time(),
                })
                await self._send(ws, outgoing_to_json(
                    OutgoingMessage(chat_id=chat_id, text=text)
                ))
                return session_id, user_id

            if cmd in ("reset", "clear"):
                await self.runtime.store.delete(f"web_current_session:{user_id}")
                await self._save_message(user_id, {
                    "type": "message", "chat_id": chat_id,
                    "text": "🔄 Контекст сброшен. Агент не помнит предыдущий разговор.", "from": "agent",
                    "timestamp": time.time(),
                })
                await self._send(ws, outgoing_to_json(
                    OutgoingMessage(chat_id=chat_id, text="🔄 Контекст сброшен.")
                ))
                return session_id, user_id

        # Handle rename at web surface level for persistence
        if isinstance(incoming, IncomingCommand) and incoming.command == "rename":
            new_name = " ".join(incoming.args) if incoming.args else ""
            if not new_name:
                await self._send(ws, outgoing_to_json(
                    OutgoingMessage(chat_id=incoming.chat_id, text="Укажите имя: /rename <название>")
                ))
            else:
                # Check for duplicate names
                is_dup = False
                for key in await self.runtime.store.keys(f"web_chat_name:{user_id}:"):
                    existing = await self.runtime.store.get(key)
                    if existing and existing.lower() == new_name.lower():
                        cid = key.rsplit(":", 1)[-1]
                        if cid != incoming.chat_id:
                            is_dup = True
                            break
                if is_dup:
                    await self._send(ws, outgoing_to_json(
                        OutgoingMessage(chat_id=incoming.chat_id, text=f"Чат с именем «{new_name}» уже существует")
                    ))
                    return session_id, user_id
                chat_id = incoming.chat_id
                await self.runtime.store.set(f"web_chat_name:{user_id}:{chat_id}", new_name)
                await self._save_message(user_id, {
                    "type": "message", "chat_id": chat_id,
                    "text": f"Переименован в: {new_name}", "from": "agent",
                    "timestamp": time.time(),
                })
                await self._send(ws, outgoing_to_json(
                    OutgoingMessage(chat_id=chat_id, text=f"Переименован в: {new_name}")
                ))
                await self._send(ws, json.dumps(
                    {"type": "chat_name", "chat_id": chat_id, "name": new_name}
                ))
            return session_id, user_id

        try:
            outgoing = await self.runtime.dispatcher.dispatch(incoming)
        except PlatformError as exc:
            logger.warning("web_platform_error", user_id=user_id, code=exc.code, error=str(exc))
            outgoing = [
                OutgoingMessage(
                    chat_id=incoming.chat_id,
                    text="Сервис временно недоступен. Попробуйте ещё раз позже.",
                )
            ]
        except Exception as exc:
            logger.warning("web_dispatch_error", user_id=user_id, error=str(exc))
            outgoing = [
                OutgoingMessage(
                    chat_id=incoming.chat_id,
                    text=f"Ошибка: {exc}",
                )
            ]

        for event in outgoing:
            if isinstance(event, OutgoingMessage):
                await self._save_message(user_id, {
                    "type": "message",
                    "chat_id": event.chat_id,
                    "text": event.text,
                    "from": "agent",
                    "timestamp": time.time(),
                    "attachments": event.attachments,
                })

        await self._send_outgoing(user_id, outgoing)
        return session_id, user_id

    async def _on_binary(
        self,
        ws: web.WebSocketResponse,
        raw: bytes,
        session_id: str,
        user_id: str,
    ) -> None:
        pass

    async def _send_outgoing(self, user_id: str, outgoing: list[OutgoingEvent]) -> None:
        ws = self._connections.get(user_id)
        if ws is None:
            return
        for event in outgoing:
            await self._send(ws, outgoing_to_json(event))

    async def _history_key(self, user_id: str, chat_id: str) -> str:
        return f"web_history:{user_id}:{chat_id}"

    async def _save_message(self, user_id: str, msg: dict) -> None:
        key = await self._history_key(user_id, msg["chat_id"])
        history = await self.runtime.store.get(key) or {"messages": []}
        entry = dict(msg)
        if entry.get("attachments"):
            entry["attachments"] = [
                {
                    "type": getattr(a, "type", "document"),
                    "filename": getattr(a, "filename", None),
                    "mime_type": getattr(a, "mime_type", None),
                    "workspace_path": getattr(a, "workspace_path", None),
                    "download_url": f"/files/{a.workspace_path}" if a.workspace_path else None,
                }
                for a in entry["attachments"]
            ]
        history["messages"].append(entry)
        history["messages"] = history["messages"][-200:]
        await self.runtime.store.set(key, history)

    async def _load_history(self, user_id: str) -> dict[str, list[dict]]:
        result: dict[str, list[dict]] = {}
        for raw_key in await self.runtime.store.keys(f"web_history:{user_id}:"):
            chat_id = raw_key.rsplit(":", 1)[-1]
            data = await self.runtime.store.get(raw_key)
            if data and "messages" in data:
                result[chat_id] = data["messages"]
        return result

    async def _send_history(self, ws: web.WebSocketResponse, user_id: str) -> None:
        history = await self._load_history(user_id)
        if not history:
            return
        payload: dict = {"type": "history", "chats": history}
        chat_names = {}
        for key in await self.runtime.store.keys(f"web_chat_name:{user_id}:"):
            cid = key.rsplit(":", 1)[-1]
            name = await self.runtime.store.get(key)
            if name:
                chat_names[cid] = name
        if chat_names:
            payload["chat_names"] = chat_names
        archived_chats = []
        for key in await self.runtime.store.keys(f"web_chat_archived:{user_id}:"):
            cid = key.rsplit(":", 1)[-1]
            val = await self.runtime.store.get(key)
            if val:
                archived_chats.append(cid)
        if archived_chats:
            payload["archived"] = archived_chats
        await self._send(ws, json.dumps(payload, ensure_ascii=False))

    async def handle_file_download(self, request: web.Request) -> web.Response:
        filepath = self.runtime.workspace_dir / request.match_info["path"]
        if not filepath.exists() or not filepath.is_file():
            raise web.HTTPNotFound
        safe_path = filepath.resolve()
        safe_workspace = self.runtime.workspace_dir.resolve()
        if not str(safe_path).startswith(str(safe_workspace)):
            raise web.HTTPForbidden
        return web.FileResponse(filepath)

    async def handle_upload(self, request: web.Request) -> web.Response:
        reader = await request.multipart()
        field = await reader.next()
        if not field or not field.filename:
            return web.json_response({"error": "no file"}, status=400)

        user_id = request.query.get("user_id", "unknown")
        safe_name = re.sub(r"[^\w.-]", "_", field.filename)
        filename = f"{user_id}_{safe_name}"
        workspace = self.runtime.workspace_dir
        filepath = workspace / filename
        filepath.parent.mkdir(parents=True, exist_ok=True)

        with open(filepath, "wb") as f:
            while True:
                chunk = await field.read_chunk()
                if not chunk:
                    break
                f.write(chunk)

        return web.json_response({
            "attachment_id": filename,
            "filename": field.filename,
            "workspace_path": filename,
        })

    async def _send(self, ws: web.WebSocketResponse, text: str) -> None:
        try:
            await ws.send_str(text)
        except ConnectionResetError:
            pass


async def main() -> None:
    port = int(os.environ.get("WEB_PORT", "8080"))
    runtime = build_runtime()
    bot = WebBot(runtime)

    app = web.Application()
    static_dir = Path(__file__).resolve().parent / "static"
    if static_dir.is_dir():
        app.router.add_static("/static/", path=str(static_dir), name="static")
    app.router.add_get("/ws", bot.handle_ws)

    async def index(request: web.Request) -> web.FileResponse:
        index_file = static_dir / "index.html"
        if index_file.is_file():
            return web.FileResponse(index_file)
        return web.Response(text="Web Chat surface — frontend not built", content_type="text/plain")

    app.router.add_get("/", index)
    app.router.add_post("/upload", bot.handle_upload)
    app.router.add_get("/files/{path:.*}", bot.handle_file_download)

    logger.info("Web surface starting", port=port)
    runner = web.AppRunner(app)
    await runner.setup()
    site = web.TCPSite(runner, "0.0.0.0", port)
    await site.start()

    try:
        await asyncio.Event().wait()
    finally:
        close = getattr(runtime.platform, "close", None)
        if callable(close):
            await close()
        await runner.cleanup()


if __name__ == "__main__":
    asyncio.run(main())