F(frontend): add image lightbox and derivative fallbacks

src/app/events/[slug]/page.tsx

@@ -3,7 +3,7 @@ import { notFound } from "next/navigation";
 import EventDetail from "@/views/EventDetail";
 import { PublicApiError, getPublicEventBySlug } from "@/lib/public-api";
 import { siteUrl } from "@/lib/site";
-import { getThumbUrl } from "@/lib/utils";
+import { getEventSeoImageUrl } from "@/lib/utils";
 
 type Params = Promise<{ slug: string }>;
 
@@ -31,7 +31,7 @@ export async function generateMetadata({
   const { slug } = await params;
   const event = await loadEvent(slug);
   const description = cleanText(event.description).slice(0, 160);
-  const image = event.absolute_featured_image_url || getThumbUrl(event) || `${siteUrl}/favicon.ico`;
+  const image = getEventSeoImageUrl(event) || `${siteUrl}/favicon.ico`;
 
   return {
     title: event.title,
@@ -84,7 +84,7 @@ export default async function EventDetailPage({
         : event.event_type === "on_site"
         ? "https://schema.org/OfflineEventAttendanceMode"
         : "https://schema.org/MixedEventAttendanceMode",
-    image: [event.absolute_featured_image_url || getThumbUrl(event) || `${siteUrl}/favicon.ico`],
+    image: [getEventSeoImageUrl(event) || `${siteUrl}/favicon.ico`],
     url: `${siteUrl}/events/${event.slug}`,
     organizer: {
       "@type": "Organization",

src/components/GalleryLightbox.tsx

@@ -0,0 +1,175 @@
+"use client";
+
+import * as React from "react";
+import { ChevronLeft, ChevronRight } from "lucide-react";
+import { Dialog, DialogContent, DialogDescription, DialogTitle } from "@/components/ui/dialog";
+import ProgressiveImage from "@/components/ProgressiveImage";
+import { Button } from "@/components/ui/button";
+
+export type GalleryLightboxItem = {
+  id: number | string;
+  alt: string;
+  title?: string | null;
+  previewSrc?: string | null;
+  blurSrc?: string | null;
+  fullSrc?: string | null;
+};
+
+type GalleryLightboxProps = {
+  items: GalleryLightboxItem[];
+  open: boolean;
+  initialIndex: number;
+  onOpenChange: (open: boolean) => void;
+};
+
+export default function GalleryLightbox({
+  items,
+  open,
+  initialIndex,
+  onOpenChange,
+}: GalleryLightboxProps) {
+  const [currentIndex, setCurrentIndex] = React.useState(initialIndex);
+
+  React.useEffect(() => {
+    if (open) {
+      setCurrentIndex(initialIndex);
+    }
+  }, [initialIndex, open]);
+
+  const currentItem = items[currentIndex];
+
+  const goToPrevious = React.useCallback(() => {
+    if (!items.length) {
+      return;
+    }
+    setCurrentIndex((current) => (current - 1 + items.length) % items.length);
+  }, [items.length]);
+
+  const goToNext = React.useCallback(() => {
+    if (!items.length) {
+      return;
+    }
+    setCurrentIndex((current) => (current + 1) % items.length);
+  }, [items.length]);
+
+  React.useEffect(() => {
+    if (!open) {
+      return;
+    }
+
+    const handleKeyDown = (event: KeyboardEvent) => {
+      if (event.key === "ArrowLeft") {
+        event.preventDefault();
+        goToPrevious();
+        return;
+      }
+
+      if (event.key === "ArrowRight") {
+        event.preventDefault();
+        goToNext();
+        return;
+      }
+
+      if (event.key === "Escape") {
+        onOpenChange(false);
+      }
+    };
+
+    window.addEventListener("keydown", handleKeyDown);
+    return () => window.removeEventListener("keydown", handleKeyDown);
+  }, [goToNext, goToPrevious, onOpenChange, open]);
+
+  React.useEffect(() => {
+    if (!open || !items.length) {
+      return;
+    }
+
+    const neighborIndexes = [
+      (currentIndex - 1 + items.length) % items.length,
+      (currentIndex + 1) % items.length,
+    ];
+
+    neighborIndexes.forEach((index) => {
+      const src = items[index]?.fullSrc || items[index]?.previewSrc;
+      if (!src) {
+        return;
+      }
+      const image = new window.Image();
+      image.src = src;
+    });
+  }, [currentIndex, items, open]);
+
+  if (!currentItem) {
+    return null;
+  }
+
+  return (
+    <Dialog open={open} onOpenChange={onOpenChange}>
+      <DialogContent
+        className="w-[min(96vw,1100px)] max-w-none overflow-hidden border-none bg-transparent p-0 shadow-none"
+        dir="rtl"
+      >
+        <DialogTitle className="sr-only">{currentItem.title || currentItem.alt}</DialogTitle>
+        <DialogDescription className="sr-only">
+          پیش‌نمایش تصویر {currentIndex + 1} از {items.length}
+        </DialogDescription>
+
+        <div className="relative overflow-hidden rounded-2xl border border-white/10 bg-black/90 text-white shadow-2xl">
+          <div className="relative min-h-[70vh]">
+            <button
+              type="button"
+              aria-label="تصویر قبلی"
+              className="absolute inset-y-0 left-0 z-10 w-1/4 cursor-w-resize bg-transparent"
+              onClick={goToPrevious}
+            />
+            <button
+              type="button"
+              aria-label="تصویر بعدی"
+              className="absolute inset-y-0 right-0 z-10 w-1/4 cursor-e-resize bg-transparent"
+              onClick={goToNext}
+            />
+
+            <div className="absolute left-4 top-4 z-20 flex gap-2">
+              <Button
+                type="button"
+                size="icon"
+                variant="secondary"
+                className="border-white/10 bg-black/45 text-white hover:bg-black/70"
+                onClick={goToNext}
+              >
+                <ChevronRight className="h-5 w-5" />
+              </Button>
+              <Button
+                type="button"
+                size="icon"
+                variant="secondary"
+                className="border-white/10 bg-black/45 text-white hover:bg-black/70"
+                onClick={goToPrevious}
+              >
+                <ChevronLeft className="h-5 w-5" />
+              </Button>
+            </div>
+
+            <ProgressiveImage
+              src={currentItem.fullSrc || currentItem.previewSrc}
+              blurSrc={currentItem.blurSrc || currentItem.previewSrc}
+              alt={currentItem.alt}
+              loading="eager"
+              wrapperClassName="min-h-[70vh]"
+              className="max-h-[80vh] w-full object-contain"
+            />
+          </div>
+
+          <div className="flex items-center justify-between gap-4 border-t border-white/10 bg-black/75 px-5 py-4 text-sm">
+            <div className="min-w-0">
+              <p className="truncate font-medium">{currentItem.title || currentItem.alt}</p>
+            </div>
+            <p className="shrink-0 text-white/70">
+              {currentIndex + 1} / {items.length}
+            </p>
+          </div>
+        </div>
+      </DialogContent>
+    </Dialog>
+  );
+}

src/components/ProgressiveImage.tsx

@@ -0,0 +1,72 @@
+"use client";
+
+import * as React from "react";
+import { cn } from "@/lib/utils";
+
+type ProgressiveImageProps = {
+  src?: string | null;
+  blurSrc?: string | null;
+  alt: string;
+  wrapperClassName?: string;
+  className?: string;
+  fallbackSrc?: string;
+  sizes?: string;
+  loading?: "eager" | "lazy";
+  decoding?: "async" | "sync" | "auto";
+  onClick?: React.MouseEventHandler<HTMLImageElement>;
+};
+
+const DEFAULT_FALLBACK = "/placeholder.svg";
+
+export default function ProgressiveImage({
+  src,
+  blurSrc,
+  alt,
+  wrapperClassName,
+  className,
+  fallbackSrc = DEFAULT_FALLBACK,
+  sizes,
+  loading = "lazy",
+  decoding = "async",
+  onClick,
+}: ProgressiveImageProps) {
+  const resolvedSrc = src || blurSrc || fallbackSrc;
+  const [loaded, setLoaded] = React.useState(false);
+
+  React.useEffect(() => {
+    setLoaded(false);
+  }, [resolvedSrc]);
+
+  return (
+    <div className={cn("relative overflow-hidden bg-muted", wrapperClassName)}>
+      {!loaded && (
+        <>
+          {blurSrc ? (
+            <img
+              src={blurSrc}
+              alt=""
+              aria-hidden="true"
+              className="absolute inset-0 h-full w-full scale-110 object-cover blur-2xl"
+            />
+          ) : null}
+          <div className="absolute inset-0 animate-pulse bg-muted/80" aria-hidden="true" />
+        </>
+      )}
+
+      <img
+        src={resolvedSrc}
+        alt={alt}
+        sizes={sizes}
+        loading={loading}
+        decoding={decoding}
+        onClick={onClick}
+        onLoad={() => setLoaded(true)}
+        className={cn(
+          "h-full w-full object-cover transition-opacity duration-300",
+          loaded ? "opacity-100" : "opacity-0",
+          className,
+        )}
+      />
+    </div>
+  );
+}

src/lib/types.ts

@@ -26,6 +26,8 @@ export interface UserProfileSchema {
   first_name: string;
   last_name: string;
   profile_picture?: string;
+  profile_picture_thumbnail_url?: string | null;
+  profile_picture_preview_url?: string | null;
   bio?: string;
   student_id?: string | null;
   year_of_study?: number;
@@ -110,12 +112,16 @@ export interface PostListSchema {
   excerpt?: string;
   featured_image?: string;
   absolute_featured_image_url?: string | null;
+  absolute_featured_image_thumbnail_url?: string | null;
+  absolute_featured_image_preview_url?: string | null;
   author: {
     id: number;
     username: string;
     first_name: string;
     last_name: string;
     profile_picture?: string;
+    profile_picture_thumbnail_url?: string | null;
+    profile_picture_preview_url?: string | null;
   };
   category?: {
     id: number;
@@ -198,6 +204,8 @@ export interface EventListItemSchema {
   description: string;
   featured_image?: string | null;
   absolute_featured_image_url?: string | null;
+  absolute_featured_image_thumbnail_url?: string | null;
+  absolute_featured_image_preview_url?: string | null;
   event_type: 'online' | 'on_site' | 'hybrid';
   address?: string | null;
   location?: string | null;
@@ -220,6 +228,8 @@ export interface EventGalleryItem {
   title: string;
   description: string;
   absolute_image_url?: string | null;
+  absolute_image_preview_url?: string | null;
+  absolute_image_blur_url?: string | null;
   width?: number;
   height?: number;
 }
@@ -328,6 +338,11 @@ export interface GalleryImageSchema {
   title: string;
   description?: string;
   image: string;
+  absolute_image_url?: string | null;
+  absolute_image_preview_url?: string | null;
+  absolute_image_blur_url?: string | null;
+  width?: number | null;
+  height?: number | null;
   uploaded_by: {
     id: number;
     username: string;

src/lib/utils.ts

@@ -35,11 +35,71 @@ export function formatJalali(iso?: string, withTime: boolean = true): string {
   }
 }
 
-const DEFAULT_THUMB = '/placeholder.svg';
+const DEFAULT_THUMB = "/placeholder.svg";
-export const getThumbUrl = (e: Types.EventListItemSchema) =>
+
-  e.absolute_featured_image_url ||
+const pickFirstUrl = (...values: Array<string | null | undefined>) =>
-  e.featured_image ||
+  values.find((value) => Boolean(value)) || DEFAULT_THUMB;
-  DEFAULT_THUMB;
+
+export const getEventCardImageUrl = (event: Types.EventListItemSchema) =>
+  pickFirstUrl(
+    event.absolute_featured_image_thumbnail_url,
+    event.absolute_featured_image_preview_url,
+    event.absolute_featured_image_url,
+    event.featured_image,
+  );
+
+export const getEventHeroImageUrl = (event: Types.EventListItemSchema) =>
+  pickFirstUrl(
+    event.absolute_featured_image_preview_url,
+    event.absolute_featured_image_url,
+    event.absolute_featured_image_thumbnail_url,
+    event.featured_image,
+  );
+
+export const getEventSeoImageUrl = (event: Types.EventListItemSchema) =>
+  pickFirstUrl(
+    event.absolute_featured_image_url,
+    event.absolute_featured_image_preview_url,
+    event.absolute_featured_image_thumbnail_url,
+    event.featured_image,
+  );
+
+export const getThumbUrl = getEventCardImageUrl;
+
+export const getGalleryImagePreviewUrl = (
+  image:
+    | Types.EventGalleryItem
+    | Types.GalleryImageSchema,
+) =>
+  pickFirstUrl(
+    image.absolute_image_preview_url,
+    image.absolute_image_url,
+    "image" in image ? image.image : undefined,
+  );
+
+export const getGalleryImageBlurUrl = (
+  image:
+    | Types.EventGalleryItem
+    | Types.GalleryImageSchema,
+) =>
+  pickFirstUrl(
+    image.absolute_image_blur_url,
+    image.absolute_image_preview_url,
+    image.absolute_image_url,
+    "image" in image ? image.image : undefined,
+  );
+
+export const getGalleryImageFullUrl = (
+  image:
+    | Types.EventGalleryItem
+    | Types.GalleryImageSchema,
+) =>
+  pickFirstUrl(
+    image.absolute_image_url,
+    image.absolute_image_preview_url,
+    image.absolute_image_blur_url,
+    "image" in image ? image.image : undefined,
+  );
 
 const PERSIAN_DIGITS = ['۰','۱','۲','۳','۴','۵','۶','۷','۸','۹'];
 

src/views/AdminEvents.tsx

@@ -11,8 +11,9 @@ import { Card, CardContent, CardDescription, CardHeader, CardTitle } from '@/com
 import { Input } from '@/components/ui/input';
 import { Select, SelectContent, SelectItem, SelectTrigger, SelectValue } from '@/components/ui/select';
 import { ScrollArea } from '@/components/ui/scroll-area';
+import ProgressiveImage from '@/components/ProgressiveImage';
 import { useToast } from '@/hooks/use-toast';
-import { formatJalali, formatToman, getThumbUrl, resolveErrorMessage, toPersianDigits } from '@/lib/utils';
+import { formatJalali, formatToman, getEventCardImageUrl, resolveErrorMessage, toPersianDigits } from '@/lib/utils';
 
 const EVENTS_PAGE_SIZE = 30;
 
@@ -225,11 +226,11 @@ const AdminEventsPage: React.FC = () => {
                       {sortedEvents.map((event) => (
                         <tr key={event.id} className="border-b last:border-0 hover:bg-muted/50">
                           <td className="px-3 py-2 text-right">
-                            <img
+                            <ProgressiveImage
-                              src={getThumbUrl(event)}
+                              src={getEventCardImageUrl(event)}
                               alt={event.title}
+                              wrapperClassName="h-12 w-12 rounded"
                               className="h-12 w-12 rounded object-cover"
-                              loading="lazy"
                             />
                           </td>
                           <td className="px-3 py-2 text-right cursor-pointer" onClick={() => navigate(`/admin/events/${event.id}`)}>

src/views/EventDetail.tsx

@@ -8,6 +8,8 @@ import type * as Types from "@/lib/types";
 import { Card, CardContent, CardDescription, CardHeader, CardTitle } from "@/components/ui/card";
 import { Badge } from "@/components/ui/badge";
 import { Button } from "@/components/ui/button";
+import GalleryLightbox, { type GalleryLightboxItem } from "@/components/GalleryLightbox";
+import ProgressiveImage from "@/components/ProgressiveImage";
 import { useToast } from "@/hooks/use-toast";
 import Markdown from "@/components/Markdown";
 import CouponDialogFa from "@/components/CouponDialogFa";
@@ -15,7 +17,12 @@ import {
   formatJalali,
   formatNumberPersian,
   formatToman,
-  getThumbUrl,
+  getEventCardImageUrl,
+  getEventHeroImageUrl,
+  getEventSeoImageUrl,
+  getGalleryImageBlurUrl,
+  getGalleryImageFullUrl,
+  getGalleryImagePreviewUrl,
   resolveErrorMessage,
   toPersianDigits,
 } from "@/lib/utils";
@@ -62,8 +69,9 @@ export default function EventDetail({ initialEvent = null }: EventDetailProps) {
 
   const [event, setEvent] = useState<Types.EventDetailSchema | null>(initialEvent);
   const [eventThumb, setEventThumb] = useState<string | null>(
-    initialEvent ? getThumbUrl(initialEvent) : null,
+    initialEvent ? getEventCardImageUrl(initialEvent) : null,
   );
+  const [lightboxIndex, setLightboxIndex] = useState<number | null>(null);
   const [loading, setLoading] = useState(!initialEvent);
   const [open, setOpen] = useState(false);
   const [submitting, setSubmitting] = useState(false);
@@ -94,7 +102,7 @@ export default function EventDetail({ initialEvent = null }: EventDetailProps) {
 
   const canonicalUrl = event ? `${siteUrl}/events/${event.slug}` : `${siteUrl}/events`;
   const primaryImage = event
-    ? toAbsoluteUrl(getThumbUrl(event)) ?? `${siteUrl}/favicon.ico`
+    ? toAbsoluteUrl(getEventSeoImageUrl(event)) ?? `${siteUrl}/favicon.ico`
     : `${siteUrl}/favicon.ico`;
   const pageTitle = event ? `${event.title} | ${siteName}` : `جزئیات رویداد | ${siteName}`;
   const pageDescription = sanitizeDescription(event?.description);
@@ -257,14 +265,14 @@ export default function EventDetail({ initialEvent = null }: EventDetailProps) {
 
         if (initialEvent && initialEvent.slug === slug) {
           setEvent(initialEvent);
-          setEventThumb(getThumbUrl(initialEvent));
+          setEventThumb(getEventCardImageUrl(initialEvent));
           return;
         }
 
         const data = await api.getEventBySlug(slug);
         if (cancelled) return;
         setEvent(data);
-        setEventThumb(getThumbUrl(data));
+        setEventThumb(getEventCardImageUrl(data));
       } catch (error: unknown) {
         if (cancelled) return;
         toast({
@@ -335,6 +343,19 @@ export default function EventDetail({ initialEvent = null }: EventDetailProps) {
     return { registrationOpen, remaining, full };
   }, [deadlineTs, event, nowTs, rsTs]);
 
+  const galleryItems = useMemo<GalleryLightboxItem[]>(
+    () =>
+      (event?.gallery_images ?? []).map((image) => ({
+        id: image.id,
+        alt: image.title || event?.title || "تصویر رویداد",
+        title: image.title,
+        previewSrc: getGalleryImagePreviewUrl(image),
+        blurSrc: getGalleryImageBlurUrl(image),
+        fullSrc: getGalleryImageFullUrl(image),
+      })),
+    [event],
+  );
+
   const eventStructuredData = useMemo(() => {
     if (!event) return null;
 
@@ -501,12 +522,12 @@ export default function EventDetail({ initialEvent = null }: EventDetailProps) {
         <div className="lg:col-span-2">
           <Card className="overflow-hidden">
             <div className="w-full aspect-video overflow-hidden rounded-lg">
-              <img
+              <ProgressiveImage
-                src={getThumbUrl(event)}
+                src={getEventHeroImageUrl(event)}
+                blurSrc={event.absolute_featured_image_thumbnail_url}
                 alt={event.title}
-                className="w-full h-full object-cover"
+                wrapperClassName="h-full w-full"
-                loading="lazy"
+                className="h-full w-full object-cover"
-                decoding="async"
               />
             </div>
 
@@ -529,17 +550,25 @@ export default function EventDetail({ initialEvent = null }: EventDetailProps) {
             </CardContent>
           </Card>
 
-          {event.gallery_images?.length ? (
+          {galleryItems.length ? (
             <div className="mt-6">
               <h3 className="text-lg font-semibold mb-3">گالری تصاویر</h3>
               <div className="grid grid-cols-2 sm:grid-cols-3 gap-3">
-                {event.gallery_images.map((image) => (
+                {galleryItems.map((image, index) => (
-                  <img
+                  <button
                     key={image.id}
-                    src={image.absolute_image_url || ""}
+                    type="button"
-                    alt={image.title || ""}
+                    className="overflow-hidden rounded-md text-right transition-transform hover:scale-[1.01] focus:outline-none focus:ring-2 focus:ring-primary/40"
-                    className="w-full h-36 object-cover rounded-md"
+                    onClick={() => setLightboxIndex(index)}
-                  />
+                  >
+                    <ProgressiveImage
+                      src={image.previewSrc}
+                      blurSrc={image.blurSrc}
+                      alt={image.alt}
+                      wrapperClassName="h-36 w-full"
+                      className="h-36 w-full object-cover"
+                    />
+                  </button>
                 ))}
               </div>
             </div>
@@ -608,6 +637,17 @@ export default function EventDetail({ initialEvent = null }: EventDetailProps) {
           </div>
         </div>
       </div>
+
+      <GalleryLightbox
+        items={galleryItems}
+        open={lightboxIndex !== null}
+        initialIndex={lightboxIndex ?? 0}
+        onOpenChange={(isOpen) => {
+          if (!isOpen) {
+            setLightboxIndex(null);
+          }
+        }}
+      />
     </div>
   );
 }

src/views/Events.tsx

@@ -8,8 +8,9 @@ import { Card, CardContent, CardDescription, CardHeader, CardTitle } from "@/com
 import { Badge } from "@/components/ui/badge";
 import { Input } from "@/components/ui/input";
 import { Button } from "@/components/ui/button";
+import ProgressiveImage from "@/components/ProgressiveImage";
 import type * as Types from "@/lib/types";
-import { formatJalali, formatNumberPersian, formatToman, getThumbUrl } from "@/lib/utils";
+import { formatJalali, formatNumberPersian, formatToman, getEventCardImageUrl } from "@/lib/utils";
 import { siteUrl } from "@/lib/site";
 
 type EventsProps = {
@@ -73,7 +74,7 @@ export default function Events({
 
   const ogImage = useMemo(() => {
     if (!events.length) return `${siteUrl}/favicon.ico`;
-    return toAbsoluteUrl(getThumbUrl(events[0])) ?? `${siteUrl}/favicon.ico`;
+    return toAbsoluteUrl(getEventCardImageUrl(events[0])) ?? `${siteUrl}/favicon.ico`;
   }, [events]);
 
   const listStructuredData = useMemo(() => {
@@ -93,7 +94,7 @@ export default function Events({
         listItem.endDate = eventItem.end_time;
       }
 
-      const imageUrl = toAbsoluteUrl(getThumbUrl(eventItem));
+      const imageUrl = toAbsoluteUrl(getEventCardImageUrl(eventItem));
       if (imageUrl) {
         listItem.image = imageUrl;
       }
@@ -210,12 +211,11 @@ export default function Events({
                 <Link key={event.id} to={`/events/${event.slug}`} className="block h-full">
                   <Card className="h-full flex flex-col hover:shadow-lg transition-shadow">
                     <div className="w-full aspect-video overflow-hidden rounded-lg">
-                      <img
+                      <ProgressiveImage
-                        src={getThumbUrl(event)}
+                        src={getEventCardImageUrl(event)}
                         alt={event.title}
-                        className="w-full h-full object-cover"
+                        wrapperClassName="h-full w-full"
-                        loading="lazy"
+                        className="h-full w-full object-cover"
-                        decoding="async"
                       />
                     </div>