import type { ApiTokenCreatedView, ApiTokenView, PondView } from '@dorfteich/shared';
import { useQuery, useQueryClient } from '@tanstack/react-query';
import { useState } from 'react';
import { useTranslation } from 'react-i18next';

import { FormError } from '../components/forms';
import { apiDelete, apiGet, apiPost } from '../lib/api';

const TOKENS_QUERY_KEY = ['users', 'me', 'api-tokens'] as const;

/**
 * Personal-access-token management in the user settings (issue #104):
 * create (scope, optional expiry, optional pond restriction), the one-time
 * secret reveal, and the list with revoke.
 */
export function ApiTokensSection(): React.JSX.Element {
  const { t } = useTranslation('apiTokens');
  const tokens = useQuery({
    queryKey: TOKENS_QUERY_KEY,
    queryFn: () => apiGet<ApiTokenView[]>('/users/me/api-tokens'),
  });

  return (
    <section className="settings-section api-tokens">
      <h2>{t('section.title')}</h2>
      <p className="api-tokens__intro">{t('section.intro')}</p>
      <CreateTokenForm />
      {tokens.data && tokens.data.length === 0 && <p>{t('section.empty')}</p>}
      {tokens.data && tokens.data.length > 0 && <TokenList tokens={tokens.data} />}
    </section>
  );
}

function CreateTokenForm(): React.JSX.Element {
  const { t } = useTranslation('apiTokens');
  const queryClient = useQueryClient();
  const [name, setName] = useState('');
  const [scope, setScope] = useState<'read' | 'write'>('read');
  const [expiresAt, setExpiresAt] = useState('');
  const [pondIds, setPondIds] = useState<string[]>([]);
  const [created, setCreated] = useState<ApiTokenCreatedView | null>(null);
  const [copied, setCopied] = useState(false);
  const [error, setError] = useState<unknown>(null);
  const [busy, setBusy] = useState(false);

  const ponds = useQuery({
    queryKey: ['ponds'],
    queryFn: () => apiGet<PondView[]>('/ponds'),
  });

  const submit = async (event: React.FormEvent): Promise<void> => {
    event.preventDefault();
    setError(null);
    setCreated(null);
    setCopied(false);
    setBusy(true);
    try {
      const view = await apiPost<ApiTokenCreatedView>('/users/me/api-tokens', {
        name,
        scope,
        expiresAt: expiresAt ? new Date(expiresAt).toISOString() : null,
        pondIds,
      });
      setCreated(view);
      setName('');
      setExpiresAt('');
      setPondIds([]);
      await queryClient.invalidateQueries({ queryKey: TOKENS_QUERY_KEY });
    } catch (err) {
      setError(err);
    } finally {
      setBusy(false);
    }
  };

  return (
    <form className="api-tokens__create" onSubmit={(event) => void submit(event)}>
      <FormError error={error} />
      <label>
        {t('fields.name')}
        <input
          type="text"
          value={name}
          required
          maxLength={80}
          onChange={(event) => setName(event.target.value)}
        />
      </label>
      <label>
        {t('fields.scope')}
        <select
          value={scope}
          onChange={(event) => setScope(event.target.value as 'read' | 'write')}
        >
          <option value="read">{t('fields.scopeRead')}</option>
          <option value="write">{t('fields.scopeWrite')}</option>
        </select>
      </label>
      <label>
        {t('fields.expiresAt')}
        <input
          type="date"
          value={expiresAt}
          onChange={(event) => setExpiresAt(event.target.value)}
        />
      </label>
      <fieldset className="api-tokens__ponds">
        <legend>{t('fields.ponds')}</legend>
        <p className="api-tokens__hint">{t('fields.pondsHint')}</p>
        {(ponds.data ?? []).map((pond) => (
          <label key={pond.id} className="api-tokens__pond">
            <input
              type="checkbox"
              checked={pondIds.includes(pond.id)}
              onChange={(event) =>
                setPondIds((current) =>
                  event.target.checked
                    ? [...current, pond.id]
                    : current.filter((id) => id !== pond.id),
                )
              }
            />
            {pond.name}
          </label>
        ))}
      </fieldset>
      <button type="submit" className="button" disabled={busy || !name.trim()}>
        {busy ? t('create.pending') : t('create.button')}
      </button>
      {created && (
        <div className="api-tokens__created" role="status">
          <h3>{t('create.createdTitle')}</h3>
          <p>{t('create.createdHint')}</p>
          <code className="api-tokens__secret">{created.token}</code>
          <button
            type="button"
            className="button"
            onClick={() => {
              void navigator.clipboard.writeText(created.token).then(() => setCopied(true));
            }}
          >
            {copied ? t('create.copied') : t('create.copy')}
          </button>
        </div>
      )}
    </form>
  );
}

function TokenList({ tokens }: { tokens: ApiTokenView[] }): React.JSX.Element {
  const { t } = useTranslation('apiTokens');
  const queryClient = useQueryClient();
  const [error, setError] = useState<unknown>(null);

  const revoke = async (id: string): Promise<void> => {
    if (!window.confirm(t('list.revokeConfirm'))) return;
    setError(null);
    try {
      await apiDelete(`/users/me/api-tokens/${id}`);
      await queryClient.invalidateQueries({ queryKey: TOKENS_QUERY_KEY });
    } catch (err) {
      setError(err);
    }
  };

  const statusOf = (token: ApiTokenView): 'active' | 'revoked' | 'expired' => {
    if (token.revokedAt) return 'revoked';
    if (token.expiresAt && new Date(token.expiresAt).getTime() <= Date.now()) return 'expired';
    return 'active';
  };

  return (
    <>
      <FormError error={error} />
      <table className="table api-tokens__table">
        <thead>
          <tr>
            <th>{t('fields.name')}</th>
            <th>{t('fields.scope')}</th>
            <th>{t('fields.ponds')}</th>
            <th>{t('list.created')}</th>
            <th>{t('list.lastUsed')}</th>
            <th>{t('list.expires')}</th>
            <th>{t('list.status')}</th>
            <th>
              <span className="visually-hidden">{t('common:tableActions')}</span>
            </th>
          </tr>
        </thead>
        <tbody>
          {tokens.map((token) => (
            <tr key={token.id}>
              <td>{token.name}</td>
              <td>{token.scope === 'write' ? t('fields.scopeWrite') : t('fields.scopeRead')}</td>
              <td>
                {token.ponds.length === 0
                  ? t('list.allPonds')
                  : token.ponds.map((pond) => pond.name).join(', ')}
              </td>
              <td>{new Date(token.createdAt).toLocaleDateString()}</td>
              <td>
                {token.lastUsedAt ? new Date(token.lastUsedAt).toLocaleString() : t('list.never')}
              </td>
              <td>{token.expiresAt ? new Date(token.expiresAt).toLocaleDateString() : '—'}</td>
              <td>{t(`list.${statusOf(token)}`)}</td>
              <td>
                {!token.revokedAt && (
                  <button
                    type="button"
                    className="button api-tokens__revoke"
                    onClick={() => void revoke(token.id)}
                  >
                    {t('list.revoke')}
                  </button>
                )}
              </td>
            </tr>
          ))}
        </tbody>
      </table>
    </>
  );
}