#3881 requested changes

Author: wavehassman

src/frontend/src/hooks/bom.hooks.ts

@@ -1,5 +1,5 @@
 import { useMutation, useQuery, useQueryClient } from 'react-query';
-import { Assembly, Manufacturer, Material, MaterialType, Unit, WbsNumber, wbsPipe } from 'shared';
+import { Assembly, Manufacturer, Material, MaterialType, ProjectPreview, Unit, WbsNumber, wbsPipe } from 'shared';
 import { useToast } from '../hooks/toasts.hooks';
 import {
   assignMaterialToAssembly,
@@ -326,3 +326,33 @@ export const useGetMaterialsForWbsElement = (wbsNum: WbsNumber) => {
     return data;
   });
 };
+
+export const useGetMaterialsForCar = (carNumber: number | null, projects: ProjectPreview[]) => {
+  const projectsInCar = projects.filter((p) => p.wbsNum.carNumber === carNumber);
+
+  return useQuery<Material[], Error>(
+    ['materials', 'car', carNumber ?? 'none'],
+    async () => {
+      const results = await Promise.all(
+        projectsInCar.map(async (p) => {
+          const { data } = await getMaterialsForWbsElement({
+            carNumber: p.wbsNum.carNumber,
+            projectNumber: p.wbsNum.projectNumber,
+            workPackageNumber: 0
+          });
+          return data;
+        })
+      );
+
+      const flat = results.flat();
+      const seen = new Set<string>();
+      return flat.filter((material) => {
+        const key = `${material.name.toLowerCase()}-${material.assemblyId ?? 'no-assembly'}`;
+        if (seen.has(key)) return false;
+        seen.add(key);
+        return true;
+      });
+    },
+    { enabled: carNumber !== null && projectsInCar.length > 0 }
+  );
+};