'use client';

import { useCallback, useEffect, useMemo, useState } from 'react';
import { useRouter, useSearchParams } from 'next/navigation';
import { Bot, ChevronRight, Loader2, Plus } from 'lucide-react';
import { usePublicSettings } from '@/components/id/public-settings-provider';
import { Button } from '@/components/ui/button';
import { BotCreateMiniAppContent } from '@/app/mini-apps/bot-create/content';
import { BotManageMiniAppContent } from '@/app/mini-apps/bot-manage/content';
import { useMiniAppAuth } from '@/hooks/use-mini-app-auth';
import { fetchMyBots, getApiErrorMessage, type ManagedBot } from '@/lib/api';
import { useToast } from '@/components/id/toast-provider';

type View = 'list' | 'create' | 'manage';

export function BotFatherMiniAppContent() {
  const searchParams = useSearchParams();
  const router = useRouter();
  const { projectName } = usePublicSettings();
  const { showToast } = useToast();
  const { effectiveToken, canUse, authReady, waitingForBridge, isLoading } = useMiniAppAuth();

  const initialBotId = searchParams.get('botId');
  const initialMode = searchParams.get('mode');

  const [view, setView] = useState<View>(() => {
    if (initialBotId) return 'manage';
    if (initialMode === 'create') return 'create';
    return 'list';
  });
  const [selectedBotId, setSelectedBotId] = useState<string | null>(initialBotId);
  const [bots, setBots] = useState<ManagedBot[]>([]);
  const [loadingBots, setLoadingBots] = useState(false);

  const syncUrl = useCallback(
    (nextView: View, botId?: string | null) => {
      const params = new URLSearchParams();
      if (nextView === 'create') params.set('mode', 'create');
      if (nextView === 'manage' && botId) params.set('botId', botId);
      const query = params.toString();
      router.replace(query ? `/mini-apps/bot-father?${query}` : '/mini-apps/bot-father');
    },
    [router]
  );

  const loadBots = useCallback(async () => {
    if (!effectiveToken) return;
    setLoadingBots(true);
    try {
      const response = await fetchMyBots(effectiveToken);
      setBots((response.bots ?? []).filter((bot) => !bot.isSystemBot));
    } catch (error) {
      showToast(getApiErrorMessage(error, 'Не удалось загрузить список ботов') ?? 'Ошибка');
    } finally {
      setLoadingBots(false);
    }
  }, [effectiveToken, showToast]);

  useEffect(() => {
    if (!canUse) return;
    if (view === 'list') void loadBots();
  }, [canUse, loadBots, view]);

  const selectedBot = useMemo(
    () => bots.find((bot) => bot.id === selectedBotId) ?? null,
    [bots, selectedBotId]
  );

  function openManage(botId: string) {
    setSelectedBotId(botId);
    setView('manage');
    syncUrl('manage', botId);
  }

  function openCreate() {
    setView('create');
    syncUrl('create');
  }

  function backToList() {
    setSelectedBotId(null);
    setView('list');
    syncUrl('list');
    void loadBots();
  }

  if ((isLoading || waitingForBridge || !authReady) && !effectiveToken) {
    return (
      <div className="flex min-h-screen items-center justify-center p-6 text-center text-sm text-[#667085]">
        <Loader2 className="mr-2 h-4 w-4 animate-spin" />
        Загрузка...
      </div>
    );
  }

  if (!canUse) {
    return (
      <div className="flex min-h-screen items-center justify-center p-6 text-center text-sm text-[#667085]">
        Войдите в {projectName}, чтобы управлять ботами
      </div>
    );
  }

  if (view === 'create') {
    return (
      <BotCreateMiniAppContent
        onBack={backToList}
        onCreated={(botId) => openManage(botId)}
      />
    );
  }

  if (view === 'manage' && selectedBotId) {
    return <BotManageMiniAppContent botId={selectedBotId} onBack={backToList} botHint={selectedBot?.username} />;
  }

  return (
    <div className="min-h-screen bg-[#17212b] p-4 text-white">
      <div className="mx-auto max-w-md space-y-4">
        <div className="rounded-[24px] bg-[#242f3d] p-5 shadow-xl">
          <div className="flex items-center gap-3">
            <div className="flex h-12 w-12 items-center justify-center rounded-full bg-[#3390ec]/20 text-[#3390ec]">
              <Bot className="h-6 w-6" />
            </div>
            <div>
              <h1 className="text-lg font-semibold">BotFather</h1>
              <p className="text-sm text-[#8b93a7]">Создание и настройка ваших ботов</p>
            </div>
          </div>
        </div>

        <Button className="h-12 w-full rounded-xl text-base" onClick={openCreate}>
          <Plus className="mr-2 h-5 w-5" />
          Создать нового бота
        </Button>

        <div className="rounded-[24px] bg-[#242f3d] p-4 shadow-xl">
          <p className="mb-3 text-sm font-medium text-[#c5cad3]">Мои боты</p>
          {loadingBots ? (
            <div className="flex items-center justify-center gap-2 py-8 text-sm text-[#8b93a7]">
              <Loader2 className="h-4 w-4 animate-spin" />
              Загрузка...
            </div>
          ) : bots.length === 0 ? (
            <p className="py-6 text-center text-sm text-[#8b93a7]">У вас пока нет ботов</p>
          ) : (
            <div className="space-y-2">
              {bots.map((bot) => (
                <button
                  key={bot.id}
                  type="button"
                  onClick={() => openManage(bot.id)}
                  className="flex w-full items-center gap-3 rounded-2xl bg-[#17212b] px-4 py-3 text-left transition hover:bg-[#1c2733]"
                >
                  <div className="flex h-10 w-10 items-center justify-center rounded-full bg-[#3390ec]/15 text-[#3390ec]">
                    <Bot className="h-5 w-5" />
                  </div>
                  <div className="min-w-0 flex-1">
                    <p className="truncate font-medium">{bot.name}</p>
                    <p className="truncate text-sm text-[#8b93a7]">@{bot.username}</p>
                  </div>
                  <ChevronRight className="h-5 w-5 shrink-0 text-[#667085]" />
                </button>
              ))}
            </div>
          )}
        </div>
      </div>
    </div>
  );
}