'use client';

import { CUSTOM_MODULE_PRELOAD_MAX } from '@tessera/shared';
import { useTranslations } from 'next-intl';
import { useCallback, useEffect, useState } from 'react';
import { SettingsSection } from '@/components/control-center/settings-section';
import {
  checkCustomModuleUrl,
  type CustomModule,
  CustomModuleRequestError,
  listCustomModules,
  setCustomModulePreload,
} from '@/lib/custom-modules-api';
import { useCustomModuleCacheStore } from '@/lib/stores/custom-module-cache-store';
import { useMarketplaceStore } from '@/lib/stores/marketplace-store';

/**
 * Karte „Beim Start vorladen“ in Einstellungen → Eigene Module
 * (quick-261008-who). Zeigt ALLE fuer den Benutzer sichtbaren Module
 * (gemeinsame und persoenliche) mit je einem Kontrollkaestchen und dem Zaehler
 * „x von 8“ — die Verwaltungsliste darueber zeigt nur persoenliche Eintraege,
 * beim Erreichen der Grenze muss man aber sehen, welche Module schon vorgeladen
 * werden. Die Wahl liegt serverseitig pro Benutzer (PUT .../preload); bei acht
 * gewaehlten sind die uebrigen Kaestchen gesperrt. Zieht nach Anlegen, Aendern
 * oder Loeschen (`sidebarRefreshKey`) neu.
 */
export function CustomModulePreloadSettings() {
  const t = useTranslations('customModules.preload');
  const tCommon = useTranslations('common');
  const refreshKey = useMarketplaceStore((s) => s.sidebarRefreshKey);
  const [modules, setModules] = useState<CustomModule[]>([]);
  const [loading, setLoading] = useState(true);
  const [loadFailed, setLoadFailed] = useState(false);
  const [busyId, setBusyId] = useState<string | null>(null);
  const [notice, setNotice] = useState<{ text: string; error: boolean } | null>(null);

  const load = useCallback(async () => {
    try {
      setModules(await listCustomModules());
      setLoadFailed(false);
    } catch {
      setLoadFailed(true);
    } finally {
      setLoading(false);
    }
  }, []);

  // biome-ignore lint/correctness/useExhaustiveDependencies: refreshKey ist der Ausloeser fuer das Neuladen.
  useEffect(() => {
    load();
  }, [load, refreshKey]);

  const count = modules.filter((m) => m.preload === true).length;
  const full = count >= CUSTOM_MODULE_PRELOAD_MAX;

  const toggle = async (mod: CustomModule) => {
    const next = mod.preload !== true;
    setNotice(null);
    setBusyId(mod.id);
    try {
      await setCustomModulePreload(mod.id, next);
      setModules((all) => all.map((m) => (m.id === mod.id ? { ...m, preload: next } : m)));
      const store = useCustomModuleCacheStore.getState();
      if (!next) store.setPinned(mod.id, false);
      else if (checkCustomModuleUrl(mod.url) === 'ok') {
        store.preload({ id: mod.id, name: mod.name, url: mod.url });
      }
    } catch (err) {
      const limit = err instanceof CustomModuleRequestError && err.status === 409;
      setNotice({
        text: limit ? t('limitReached', { max: CUSTOM_MODULE_PRELOAD_MAX }) : t('saveError'),
        error: !limit,
      });
    } finally {
      setBusyId(null);
    }
  };

  return (
    <SettingsSection
      title={t('settingsTitle')}
      description={t('settingsDescription', { max: CUSTOM_MODULE_PRELOAD_MAX })}
    >
      {loading ? (
        <p className="text-sm text-muted-foreground">{tCommon('loading')}</p>
      ) : loadFailed ? (
        <p role="alert" className="text-sm text-destructive">
          {t('loadError')}
        </p>
      ) : modules.length === 0 ? (
        <p className="text-sm text-muted-foreground">{t('empty')}</p>
      ) : (
        <div className="flex flex-col gap-3">
          <p className="text-sm text-muted-foreground" data-testid="preload-count">
            {t('count', { count, max: CUSTOM_MODULE_PRELOAD_MAX })}
          </p>
          {full && (
            <p className="text-sm text-muted-foreground">
              {t('limitReached', { max: CUSTOM_MODULE_PRELOAD_MAX })}
            </p>
          )}
          <ul className="flex flex-col divide-y divide-border">
            {modules.map((mod) => {
              const checked = mod.preload === true;
              const inputId = `preload-${mod.id}`;
              return (
                <li key={mod.id} className="flex items-center gap-3 py-2">
                  <input
                    id={inputId}
                    type="checkbox"
                    checked={checked}
                    disabled={busyId !== null || (full && !checked)}
                    onChange={() => toggle(mod)}
                  />
                  <label htmlFor={inputId} className="min-w-0 flex-1 truncate text-sm">
                    {mod.name}
                  </label>
                  <span className="shrink-0 text-xs text-muted-foreground">
                    {mod.personal ? t('personal') : t('shared')}
                  </span>
                </li>
              );
            })}
          </ul>
          {notice && (
            <p
              role="status"
              className={`text-sm ${notice.error ? 'text-destructive' : 'text-muted-foreground'}`}
            >
              {notice.text}
            </p>
          )}
        </div>
      )}
    </SettingsSection>
  );
}