feat(public): merge secondary media gallery images with URL dedup

apps/api/src/public/public.service.spec.ts

@@ -435,6 +435,7 @@ describe('PublicService', () => {
           sizeChart: { rows: [{ sizeName: 'S', measurements: [{ key: 'chest', cm: '94' }] }, { sizeName: 'M', measurements: [{ key: 'chest', cm: '100' }] }] },
           packageSpecs: { rows: [{ sizeName: 'S' }] },
           options: { sizes: [{ name: 'S' }, { name: 'M' }] },
+          media: { images: ['http://img/pri-a', 'http://img/pri-b'], primaryImageUrl: 'http://img/pri-a' },
         },
       });
       // Secondary: duplicate Black|S with a DIFFERENT price (must be dropped,
@@ -451,6 +452,7 @@ describe('PublicService', () => {
           sizeChart: { rows: [{ sizeName: 'XXXL', measurements: [{ key: 'chest', cm: '120' }] }] },
           packageSpecs: { rows: [{ sizeName: 'M' }, { sizeName: 'XXXL' }] },
           options: { sizes: [{ name: 'XXXL' }] },
+          media: { images: ['http://img/pri-a', 'http://img/sec-x'], primaryImageUrl: 'http://img/pri-a' },
         },
       });
       const mergedGood = await prisma.good.create({
@@ -483,6 +485,11 @@ describe('PublicService', () => {
         // Options: sizes unioned S/M + XXXL.
         const optSizes = (detail.options as any).sizes.map((s: any) => s.name).sort();
         expect(optSizes).toEqual(['M', 'S', 'XXXL']);
+        // Media gallery: primary images first, secondary-only URL appended,
+        // duplicate URL (pri-a) kept once.
+        const media = detail.media as any;
+        expect(media.images).toEqual(['http://img/pri-a', 'http://img/pri-b', 'http://img/sec-x']);
+        expect(media.primaryImageUrl).toBe('http://img/pri-a');
       } finally {
         await prisma.goodOriginGood.deleteMany({ where: { goodId: mergedGood.id } });
         await prisma.good.delete({ where: { id: mergedGood.id } });

apps/api/src/public/public.service.ts

@@ -385,7 +385,7 @@ export class PublicService {
         designArea: detail?.designArea ?? null,
         pictureRequest: detail?.pictureRequest ?? null,
       },
-      media: (detail?.media as Record<string, unknown> | null) ?? null,
+      media: this.mergeMedia(detail, secondaryDetails),
       mediaByColor: this.groupImagesByColor(allVariants),
       options: this.mergeOptions(detail, secondaryDetails),
       sizeChart: this.mergeRowsByKey(detail, secondaryDetails, 'sizeChart'),
@@ -496,6 +496,35 @@ export class PublicService {
     return merged;
   }
 
+  /**
+   * Merge the gallery `media` across details: primary images first,
+   * secondary-only image URLs appended (URL-deduped). `primaryImageUrl`
+   * stays the primary's.
+   */
+  private mergeMedia(
+    primary: PublicGoodRow['originGood']['detail'],
+    secondaries: NonNullable<PublicGoodRow['originGood']['detail']>[],
+  ): Record<string, unknown> | null {
+    const toImages = (media: unknown): string[] => {
+      const images = (media as { images?: unknown } | null)?.images;
+      return Array.isArray(images) ? images.filter((u): u is string => typeof u === 'string') : [];
+    };
+    const primaryMedia = (primary?.media as Record<string, unknown> | null) ?? null;
+    if (!primaryMedia && secondaries.length === 0) return null;
+    const images = toImages(primaryMedia);
+    const seen = new Set(images);
+    for (const sec of secondaries) {
+      for (const url of toImages(sec.media)) {
+        if (!seen.has(url)) {
+          seen.add(url);
+          images.push(url);
+        }
+      }
+    }
+    if (images.length === 0) return null;
+    return { ...(primaryMedia ?? {}), images };
+  }
+
   private async buildTagGroupFilters(
     selectedGroups: PublicTagFilterDto[],
   ): Promise<Prisma.GoodWhereInput[]> {