from aiogram import F, Router, types
from aiogram.fsm.context import FSMContext
from aiogram.fsm.state import State, StatesGroup
from aiogram.types import CallbackQuery, InlineKeyboardButton
from aiogram.utils.keyboard import InlineKeyboardBuilder
from sqlalchemy import delete, func, select, update
from sqlalchemy.ext.asyncio import AsyncSession

from database import get_servers
from database.models import Key, Server
from filters.admin import IsAdminFilter
from handlers.buttons import BACK

from ..panel.keyboard import build_admin_back_kb
from .keyboard import AdminServerCallback, build_manage_server_kb

router = Router()


class ServerLimitState(StatesGroup):
    waiting_for_limit = State()


@router.callback_query(
    AdminServerCallback.filter(F.action == "manage"), IsAdminFilter()
)
async def handle_server_manage(
    callback_query: CallbackQuery,
    callback_data: AdminServerCallback,
    session: AsyncSession,
):
    server_name = callback_data.data
    servers = await get_servers(session=session, include_enabled=True)

    cluster_name, server = next(
        (
            (c, s)
            for c, cs in servers.items()
            for s in cs
            if s["server_name"] == server_name
        ),
        (None, None),
    )

    if server:
        api_url = server["api_url"]
        subscription_url = server["subscription_url"]
        inbound_id = server["inbound_id"]
        max_keys = server.get("max_keys")
        limit_display = f"{max_keys}" if max_keys else "не задан"

        text = (
            f"<b>🔧 Информация о сервере {server_name}:</b>\n\n"
            f"<b>📡 API URL:</b> {api_url}\n"
            f"<b>🌐 Subscription URL:</b> {subscription_url}\n"
            f"<b>🔑 Inbound ID:</b> {inbound_id}\n"
            f"<b>📈 Лимит ключей:</b> {limit_display}"
        )

        await callback_query.message.edit_text(
            text=text,
            reply_markup=build_manage_server_kb(
                server_name, cluster_name, enabled=server.get("enabled", True)
            ),
        )
    else:
        await callback_query.message.edit_text(text="❌ Сервер не найден.")


@router.callback_query(
    AdminServerCallback.filter(F.action == "delete"), IsAdminFilter()
)
async def process_callback_delete_server(
    callback_query: CallbackQuery,
    callback_data: AdminServerCallback,
    state: FSMContext,
    session: AsyncSession,
):
    from ..clusters.clusters_handler import AdminClusterStates

    server_name = callback_data.data

    servers_dict = await get_servers(session)
    cluster_name = None
    for c_name, server_list in servers_dict.items():
        if any(s["server_name"] == server_name for s in server_list):
            cluster_name = c_name
            break

    if not cluster_name:
        await callback_query.message.edit_text(
            text=f"❌ Не удалось найти кластер для сервера '{server_name}'.",
            reply_markup=build_admin_back_kb("clusters"),
        )
        return

    stmt_keys_count = select(func.count()).where(Key.server_id == server_name)
    result = await session.execute(stmt_keys_count)
    keys_count = result.scalar_one()

    if keys_count > 0:
        await state.update_data(server_name=server_name, cluster_name=cluster_name)

        subq = (
            select(func.count())
            .where(Key.server_id == Server.server_name)
            .correlate(Server)
            .scalar_subquery()
        )

        stmt_all_servers = select(Server.server_name, subq.label("key_count")).where(
            Server.server_name != server_name
        )
        result = await session.execute(stmt_all_servers)
        all_servers = result.all()

        if all_servers:
            builder = InlineKeyboardBuilder()
            for s_name, key_count in all_servers:
                builder.row(
                    InlineKeyboardButton(
                        text=f"{s_name} ({key_count})",
                        callback_data=f"transfer_to_server|{s_name}|{server_name}",
                    )
                )
            builder.row(
                InlineKeyboardButton(
                    text=BACK,
                    callback_data=AdminServerCallback(
                        action="manage", data=server_name
                    ).pack(),
                )
            )

            await callback_query.message.edit_text(
                text=f"⚠️ На сервере '{server_name}' есть {keys_count} ключей. Выберите сервер для переноса ключей:",
                reply_markup=builder.as_markup(),
            )
            await state.set_state(AdminClusterStates.waiting_for_server_transfer)
            return

    stmt_remaining = select(func.count()).where(
        (Server.cluster_name == cluster_name) & (Server.server_name != server_name)
    )
    result = await session.execute(stmt_remaining)
    remaining_servers = result.scalar_one()

    if remaining_servers == 0:
        stmt_other_clusters = (
            select(Server.cluster_name)
            .distinct()
            .where(Server.cluster_name != cluster_name)
        )
        result = await session.execute(stmt_other_clusters)
        other_clusters = result.scalars().all()

        if other_clusters:
            stmt_cluster_keys = select(func.count()).where(
                Key.server_id == cluster_name
            )
            result = await session.execute(stmt_cluster_keys)
            cluster_keys_count = result.scalar_one()

            if cluster_keys_count > 0:
                await state.update_data(
                    server_name=server_name, cluster_name=cluster_name
                )

                subq_cluster = (
                    select(func.count())
                    .where(Key.server_id == Server.cluster_name)
                    .correlate(Server)
                    .scalar_subquery()
                )

                stmt_all_clusters = (
                    select(Server.cluster_name, subq_cluster.label("key_count"))
                    .where(Server.cluster_name != cluster_name)
                    .group_by(Server.cluster_name)
                )
                result = await session.execute(stmt_all_clusters)
                all_clusters = result.all()

                builder = InlineKeyboardBuilder()
                for cl_name, key_count in all_clusters:
                    builder.row(
                        InlineKeyboardButton(
                            text=f"{cl_name} ({key_count})",
                            callback_data=f"transfer_to_cluster|{cl_name}|{cluster_name}|{server_name}",
                        )
                    )
                builder.row(
                    InlineKeyboardButton(
                        text=BACK,
                        callback_data=AdminServerCallback(
                            action="manage", data=server_name
                        ).pack(),
                    )
                )

                await callback_query.message.edit_text(
                    text=f"⚠️ Это последний сервер в кластере '{cluster_name}'. На кластере есть {cluster_keys_count} ключей. Выберите кластер для переноса ключей:",
                    reply_markup=builder.as_markup(),
                )
                await state.set_state(AdminClusterStates.waiting_for_cluster_transfer)
                return

        stmt_delete = delete(Server).where(
            (Server.cluster_name == cluster_name) & (Server.server_name == server_name)
        )
        await session.execute(stmt_delete)
        await session.commit()
        await callback_query.message.edit_text(
            text=f"✅ Сервер '{server_name}' удален. Кластер '{cluster_name}' также удален, так как в нем не осталось серверов.",
            reply_markup=build_admin_back_kb("clusters"),
        )
    else:
        stmt_delete = delete(Server).where(
            (Server.cluster_name == cluster_name) & (Server.server_name == server_name)
        )
        await session.execute(stmt_delete)
        await session.commit()
        await callback_query.message.edit_text(
            text=f"✅ Сервер '{server_name}' удален.",
            reply_markup=build_admin_back_kb("clusters"),
        )


@router.callback_query(
    AdminServerCallback.filter(F.action.in_(["enable", "disable"])), IsAdminFilter()
)
async def toggle_server_enabled(
    callback_query: CallbackQuery,
    callback_data: AdminServerCallback,
    session: AsyncSession,
):
    server_name = callback_data.data
    action = callback_data.action

    new_status = action == "enable"

    await session.execute(
        update(Server)
        .where(Server.server_name == server_name)
        .values(enabled=new_status)
    )
    await session.commit()

    servers = await get_servers(session=session, include_enabled=True)

    cluster_name, server = next(
        (
            (c, s)
            for c, cs in servers.items()
            for s in cs
            if s["server_name"] == server_name
        ),
        (None, None),
    )

    if not server:
        await callback_query.message.edit_text("❌ Сервер не найден.")
        return

    max_keys = server.get("max_keys")
    limit_display = f"{max_keys}" if max_keys else "не задан"

    text = (
        f"<b>🔧 Информация о сервере {server_name}:</b>\n\n"
        f"<b>📡 API URL:</b> {server['api_url']}\n"
        f"<b>🌐 Subscription URL:</b> {server['subscription_url']}\n"
        f"<b>🔑 Inbound ID:</b> {server['inbound_id']}\n"
        f"<b>📈 Лимит ключей:</b> {limit_display}"
    )

    await callback_query.message.edit_text(
        text=text,
        reply_markup=build_manage_server_kb(
            server_name, cluster_name, enabled=new_status
        ),
    )


@router.callback_query(
    AdminServerCallback.filter(F.action == "set_limit"), IsAdminFilter()
)
async def ask_server_limit(
    callback_query: CallbackQuery, callback_data: AdminServerCallback, state: FSMContext
):
    server_name = callback_data.data
    await state.set_state(ServerLimitState.waiting_for_limit)
    await state.update_data(server_name=server_name)
    await callback_query.message.edit_text(
        f"Введите лимит ключей для сервера <b>{server_name}</b> (целое число, 0 — без лимита):",
    )


@router.message(ServerLimitState.waiting_for_limit, IsAdminFilter())
async def save_server_limit(
    message: types.Message, state: FSMContext, session: AsyncSession
):
    try:
        limit = int(message.text.strip())
        if limit < 0:
            raise ValueError

        data = await state.get_data()
        server_name = data["server_name"]

        new_value = limit if limit > 0 else None

        await session.execute(
            update(Server)
            .where(Server.server_name == server_name)
            .values(max_keys=new_value)
        )
        await session.commit()

        servers = await get_servers(session=session, include_enabled=True)
        cluster_name, server = next(
            (
                (c, s)
                for c, cs in servers.items()
                for s in cs
                if s["server_name"] == server_name
            ),
            (None, None),
        )

        if not server:
            await message.answer("❌ Сервер не найден.")
            await state.clear()
            return

        max_keys = server.get("max_keys")
        limit_display = f"{max_keys}" if max_keys is not None else "не задан"

        text = (
            f"<b>🔧 Информация о сервере {server_name}:</b>\n\n"
            f"<b>📡 API URL:</b> {server['api_url']}\n"
            f"<b>🌐 Subscription URL:</b> {server['subscription_url']}\n"
            f"<b>🔑 Inbound ID:</b> {server['inbound_id']}\n"
            f"<b>📈 Лимит ключей:</b> {limit_display}"
        )

        await message.answer(
            text,
            reply_markup=build_manage_server_kb(
                server_name, cluster_name, enabled=server.get("enabled", True)
            ),
        )
        await state.clear()

    except ValueError:
        await message.answer("❌ Введите корректное целое число (0 = без лимита)")