'use client';

import { useMemo, useState } from 'react';
import { Copy, ExternalLink } from 'lucide-react';
import { Button } from '@/components/ui/button';
import { Tabs, TabsContent, TabsList, TabsTrigger } from '@/components/ui/tabs';
import { OAuthClient } from '@/lib/api';
import { buildOneTapExamples } from '@/lib/one-tap-examples';
import { OAuthEndpoints } from '@/lib/oauth-url';

function SnippetBlock({ code, onCopy }: { code: string; onCopy: (value: string, label: string) => void }) {
  return (
    <div className="relative rounded-2xl bg-[#111827] p-4 text-xs text-[#e5e7eb]">
      <Button
        type="button"
        variant="ghost"
        size="icon"
        className="absolute right-2 top-2 h-8 w-8 text-white hover:bg-white/10 hover:text-white"
        aria-label="Скопировать код"
        onClick={() => onCopy(code, 'Код интеграции')}
      >
        <Copy className="h-4 w-4" />
      </Button>
      <pre className="max-h-72 overflow-auto whitespace-pre-wrap break-all pr-10">{code}</pre>
    </div>
  );
}

export function OAuthClientOneTapSection({
  client,
  endpoints,
  frontendBase,
  projectName,
  onCopy
}: {
  client: OAuthClient;
  endpoints: OAuthEndpoints;
  frontendBase: string;
  projectName: string;
  onCopy: (value: string, label: string) => void;
}) {
  const primaryRedirect = client.redirectUris[0] ?? `${frontendBase}/auth/callback`;
  const examples = useMemo(
    () =>
      buildOneTapExamples(
        {
          apiBase: endpoints.issuer,
          frontendBase,
          widgetUrl: endpoints.widgetUrl,
          fedcmConfigUrl: endpoints.fedcmConfigUrl,
          webIdentityUrl: endpoints.webIdentityUrl,
          fedcmDiscoverUrl: endpoints.fedcmDiscoverUrl,
          projectName
        },
        client.clientId,
        primaryRedirect
      ),
    [client.clientId, endpoints, frontendBase, primaryRedirect, projectName]
  );
  const [activeTab, setActiveTab] = useState(examples[0]?.id ?? 'widget-script');

  return (
    <section className="space-y-4 rounded-2xl border border-[#eceef4] p-4">
      <div>
        <h3 className="font-medium">One Tap Login</h3>
        <p className="mt-1 text-xs leading-relaxed text-[#667085]">
          FedCM (Chrome/Edge) и виджет <code className="rounded bg-[#f4f5f8] px-1 py-0.5">sso-widget.js</code> с popup fallback.
          Убедитесь, что в настройках указаны <strong>PUBLIC_API_URL</strong> и <strong>PUBLIC_FRONTEND_URL</strong>.
        </p>
      </div>

      <div className="grid gap-2 sm:grid-cols-2">
        <CopyRowCompact label="FedCM config" value={endpoints.fedcmConfigUrl} onCopy={onCopy} />
        <CopyRowCompact label="Web identity" value={endpoints.webIdentityUrl} onCopy={onCopy} />
        <CopyRowCompact label="Виджет" value={endpoints.widgetUrl} onCopy={onCopy} />
        <CopyRowCompact label="Discover" value={endpoints.fedcmDiscoverUrl} onCopy={onCopy} />
      </div>

      <Tabs value={activeTab} onValueChange={setActiveTab}>
        <TabsList className="mb-2 flex h-auto max-w-full flex-wrap gap-1">
          {examples.map((example) => (
            <TabsTrigger key={example.id} value={example.id} className="text-xs">
              {example.label}
            </TabsTrigger>
          ))}
        </TabsList>
        {examples.map((example) => (
          <TabsContent key={example.id} value={example.id}>
            <SnippetBlock code={example.code} onCopy={onCopy} />
          </TabsContent>
        ))}
      </Tabs>

      <div className="rounded-xl bg-[#eef4ff] px-4 py-3 text-xs text-[#1d4ed8]">
        <p className="font-medium">Проверка FedCM</p>
        <ol className="mt-2 list-decimal space-y-1 pl-4">
          <li>Войдите на IdP ({frontendBase}) в этом браузере.</li>
          <li>Откройте сайт клиента с виджетом — Chrome покажет нативный диалог или плашку One Tap.</li>
          <li>
            <code>login_url</code> в config.json должен быть на том же домене, что и config (
            <code>{endpoints.issuer}/auth/login</code>), не на SSO-домене.
          </li>
          <li>
            <code>configURL</code> для FedCM: <code>{endpoints.fedcmConfigUrl}</code> (не{' '}
            <code>{frontendBase}/idp-api/fedcm/config.json</code>).
          </li>
          <li>
            При ошибке NetworkError проверьте, что <code>PUBLIC_API_URL</code> = <code>{endpoints.issuer}</code>.
          </li>
        </ol>
        <a
          href={`${frontendBase.replace(/\/$/, '')}/sso-widget.js`}
          target="_blank"
          rel="noreferrer"
          className="mt-2 inline-flex items-center gap-1 font-medium hover:underline"
        >
          Открыть sso-widget.js
          <ExternalLink className="h-3.5 w-3.5" />
        </a>
      </div>
    </section>
  );
}

function CopyRowCompact({
  label,
  value,
  onCopy
}: {
  label: string;
  value: string;
  onCopy: (value: string, label: string) => void;
}) {
  return (
    <div className="rounded-xl bg-[#f4f5f8] p-3">
      <div className="mb-1 flex items-center justify-between gap-2">
        <span className="text-xs font-medium">{label}</span>
        <Button variant="ghost" size="icon" className="h-7 w-7" aria-label={`Скопировать ${label}`} onClick={() => onCopy(value, label)}>
          <Copy className="h-3.5 w-3.5" />
        </Button>
      </div>
      <code className="block break-all text-[11px] text-[#667085]">{value}</code>
    </div>
  );
}