import { useEffect, useMemo, useRef, useState } from 'react';
import { ArrowLeft, ExternalLink, Loader2, RefreshCcw, ShoppingBag } from 'lucide-react';
import { useTranslation } from 'react-i18next';
import { useNavigate } from 'react-router-dom';
import { Button } from '@/components/ui/button';
import { useYinianStore } from '@/stores/yinian';
import { buildProductCenterSrc, getProductCenterBaseUrl } from './url';

const PRODUCT_CENTER_PARTITION = 'persist:yinian-travel-resource-ordering';

type ProductCenterWebviewElement = HTMLElement & {
  reload?: () => void;
};

export function ProductCenter() {
  const { t } = useTranslation('appCenter');
  const navigate = useNavigate();
  const session = useYinianStore((state) => state.session);
  const webviewRef = useRef<ProductCenterWebviewElement | null>(null);
  const [reloadKey, setReloadKey] = useState(0);
  const [isLoading, setIsLoading] = useState(true);
  const baseUrl = useMemo(() => getProductCenterBaseUrl(), []);
  const embeddedSrc = useMemo(() => buildProductCenterSrc({
    baseUrl,
    reloadKey,
    session,
  }), [baseUrl, reloadKey, session]);

  useEffect(() => {
    const webview = webviewRef.current;
    if (!webview) return;

    const handleStart = () => setIsLoading(true);
    const handleStop = () => setIsLoading(false);

    webview.addEventListener('did-start-loading', handleStart);
    webview.addEventListener('did-stop-loading', handleStop);
    webview.addEventListener('did-fail-load', handleStop);

    return () => {
      webview.removeEventListener('did-start-loading', handleStart);
      webview.removeEventListener('did-stop-loading', handleStop);
      webview.removeEventListener('did-fail-load', handleStop);
    };
  }, [reloadKey]);

  const reloadApp = () => {
    setIsLoading(true);
    if (typeof webviewRef.current?.reload === 'function') {
      webviewRef.current.reload();
      return;
    }
    setReloadKey((value) => value + 1);
  };

  const openExternal = () => {
    void window.electron.openExternal(baseUrl);
  };

  return (
    <div data-testid="product-center-page" className="-m-6 flex h-[calc(100vh-2.5rem)] min-h-0 flex-col overflow-hidden bg-white text-slate-950 dark:bg-slate-950 dark:text-slate-50">
      <header className="grid h-14 shrink-0 grid-cols-[minmax(0,1fr)_auto_minmax(0,1fr)] items-center gap-3 border-b border-slate-200/80 bg-white/70 px-4 backdrop-blur dark:border-white/10 dark:bg-slate-950/80">
        <div className="flex min-w-0 items-center gap-2">
          <Button
            type="button"
            variant="outline"
            size="sm"
            onClick={() => navigate('/app-center')}
            data-testid="product-center-back"
            className="shrink-0"
          >
            <ArrowLeft className="h-4 w-4" />
            {t('productCenter.back')}
          </Button>
          <Button
            type="button"
            variant="outline"
            size="icon"
            onClick={reloadApp}
            aria-label={t('productCenter.reload')}
            title={t('productCenter.reload')}
            className="h-9 w-9 shrink-0"
          >
            <RefreshCcw className="h-4 w-4" />
          </Button>
          <div className="min-w-0">
            <h1 className="truncate text-base font-semibold tracking-normal">
              {t('productCenter.title')}
            </h1>
          </div>
        </div>
        <div className="flex min-w-0 items-center justify-self-center rounded-lg border border-slate-200/70 bg-white/60 px-3 py-1.5 text-xs font-medium text-slate-600 dark:border-white/10 dark:bg-white/5 dark:text-slate-300">
          <ShoppingBag className="mr-1.5 h-3.5 w-3.5 text-[#075985] dark:text-blue-200" />
          <span className="truncate">{t('productCenter.badge')}</span>
        </div>
        <div className="flex min-w-0 justify-end">
          <Button
            type="button"
            variant="outline"
            size="sm"
            onClick={openExternal}
            data-testid="product-center-open-external"
            className="shrink-0"
          >
            <ExternalLink className="h-4 w-4" />
            {t('productCenter.openExternal')}
          </Button>
        </div>
      </header>

      <section className="relative min-h-0 flex-1 overflow-hidden bg-white dark:bg-slate-950">
        <webview
          key={reloadKey}
          ref={webviewRef}
          data-testid="product-center-frame"
          src={embeddedSrc}
          partition={PRODUCT_CENTER_PARTITION}
          title={t('productCenter.frameTitle')}
          className="absolute inset-0 h-full w-full border-0 bg-white dark:bg-slate-950"
          allowpopups={false}
          webpreferences="contextIsolation=yes,nodeIntegration=no"
        />
        {isLoading && (
          <div className="pointer-events-none absolute inset-0 flex items-center justify-center bg-white/92 p-6 text-center dark:bg-slate-950/92">
            <div className="max-w-md">
              <div className="mx-auto flex h-11 w-11 items-center justify-center rounded-lg bg-[#EAF5FA] text-[#075985] dark:bg-[#1E3A8A]/30 dark:text-blue-100">
                <Loader2 className="h-5 w-5 animate-spin" />
              </div>
              <div className="mt-4 text-base font-semibold text-slate-950 dark:text-slate-50">
                {t('productCenter.loading')}
              </div>
              <p className="mt-2 text-sm leading-6 text-muted-foreground">
                {t('productCenter.loadingDesc')}
              </p>
            </div>
          </div>
        )}
      </section>
    </div>
  );
}

export default ProductCenter;