feat: Add product dependencies (requirements and exclusions) to database, admin UI and wizard validation

shop/app/admin/products/page.tsx

@@ -39,7 +39,8 @@ async function ProductDataWrapper() {
 
 async function CreateProductAction() {
   const categories = await getCategories()
+  const products = await getProducts()
   return (
-    <CreateProductDialog categories={categories} />
+    <CreateProductDialog categories={categories} products={products} />
   )
 }

shop/components/admin/create-product-dialog.tsx

@@ -58,15 +58,29 @@ const productSchema = z.object({
   billing_interval: z.enum(['one_time', 'monthly']).default('monthly'),
   show_in_kauf: z.boolean().default(true),
   show_in_abo: z.boolean().default(true),
+  requirements: z.array(z.string()).default([]),
+  exclusions: z.array(z.string()).default([]),
   modules: z.array(moduleSchema).default([]),
 })
 
 type ProductFormValues = z.infer<typeof productSchema>
 
-export function CreateProductDialog({ children, categories, product }: { children?: React.ReactNode, categories: Category[], product?: Product }) {
+export function CreateProductDialog({
+  children,
+  categories,
+  product,
+  products = []
+}: {
+  children?: React.ReactNode
+  categories: Category[]
+  product?: Product
+  products?: Product[]
+}) {
   const [open, setOpen] = useState(false)
   const router = useRouter()
 
+  const otherProducts = products.filter(p => p.id !== product?.id)
+
   const form = useForm<ProductFormValues>({
     resolver: zodResolver(productSchema) as any,
     defaultValues: {
@@ -77,6 +91,8 @@ export function CreateProductDialog({ children, categories, product }: { childre
       billing_interval: product?.billing_interval || 'monthly',
       show_in_kauf: product ? (product.show_in_kauf ?? true) : true,
       show_in_abo: product ? (product.show_in_abo ?? true) : true,
+      requirements: product?.requirements || [],
+      exclusions: product?.exclusions || [],
       modules: product?.modules?.map(m => ({
         id: m.id,
         name: m.name,
@@ -275,6 +291,100 @@ export function CreateProductDialog({ children, categories, product }: { childre
                   )}
                 />
 
+                <div className="grid grid-cols-2 gap-4">
+                  {/* Product Requirements */}
+                  <FormField
+                    control={form.control}
+                    name="requirements"
+                    render={({ field: reqField }) => (
+                      <FormItem className="flex flex-col gap-1.5">
+                        <FormLabel className="text-slate-900 dark:text-white font-medium">Benötigte Artikel</FormLabel>
+                        <ScrollArea className="h-32 border border-slate-200 dark:border-white/10 rounded p-3 bg-slate-50 dark:bg-white/5">
+                          {otherProducts.length === 0 ? (
+                            <p className="text-xs text-slate-500 italic">Keine anderen Artikel vorhanden.</p>
+                          ) : (
+                            <div className="space-y-2">
+                              {otherProducts.map(other => {
+                                const checked = (reqField.value || []).includes(other.id)
+                                return (
+                                  <div key={other.id} className="flex items-center space-x-2">
+                                    <Checkbox
+                                      id={`prod-req-${other.id}`}
+                                      checked={checked}
+                                      onCheckedChange={(checkedState) => {
+                                        const currentVal = reqField.value || []
+                                        if (checkedState) {
+                                          reqField.onChange([...currentVal, other.id])
+                                        } else {
+                                          reqField.onChange(currentVal.filter(id => id !== other.id))
+                                        }
+                                      }}
+                                    />
+                                    <label
+                                      htmlFor={`prod-req-${other.id}`}
+                                      className="text-xs text-slate-700 dark:text-slate-300 cursor-pointer select-none truncate block"
+                                      title={other.name}
+                                    >
+                                      {other.name}
+                                    </label>
+                                  </div>
+                                )
+                              })}
+                            </div>
+                          )}
+                        </ScrollArea>
+                        <FormMessage />
+                      </FormItem>
+                    )}
+                  />
+
+                  {/* Product Exclusions */}
+                  <FormField
+                    control={form.control}
+                    name="exclusions"
+                    render={({ field: exclField }) => (
+                      <FormItem className="flex flex-col gap-1.5">
+                        <FormLabel className="text-slate-900 dark:text-white font-medium">Schließt aus</FormLabel>
+                        <ScrollArea className="h-32 border border-slate-200 dark:border-white/10 rounded p-3 bg-slate-50 dark:bg-white/5">
+                          {otherProducts.length === 0 ? (
+                            <p className="text-xs text-slate-500 italic">Keine anderen Artikel vorhanden.</p>
+                          ) : (
+                            <div className="space-y-2">
+                              {otherProducts.map(other => {
+                                const checked = (exclField.value || []).includes(other.id)
+                                return (
+                                  <div key={other.id} className="flex items-center space-x-2">
+                                    <Checkbox
+                                      id={`prod-excl-${other.id}`}
+                                      checked={checked}
+                                      onCheckedChange={(checkedState) => {
+                                        const currentVal = exclField.value || []
+                                        if (checkedState) {
+                                          exclField.onChange([...currentVal, other.id])
+                                        } else {
+                                          exclField.onChange(currentVal.filter(id => id !== other.id))
+                                        }
+                                      }}
+                                    />
+                                    <label
+                                      htmlFor={`prod-excl-${other.id}`}
+                                      className="text-xs text-slate-700 dark:text-slate-300 cursor-pointer select-none truncate block"
+                                      title={other.name}
+                                    >
+                                      {other.name}
+                                    </label>
+                                  </div>
+                                )
+                              })}
+                            </div>
+                          )}
+                        </ScrollArea>
+                        <FormMessage />
+                      </FormItem>
+                    )}
+                  />
+                </div>
+
                 <Separator className="bg-slate-200 dark:bg-white/10" />
 
                 <div className="space-y-4">

shop/components/admin/product-list.tsx

@@ -154,7 +154,7 @@ export function ProductList({ initialProducts, categories }: { initialProducts:
           >
             <Copy className="h-4 w-4" />
           </Button>
-          <CreateProductDialog categories={categories} product={product}>
+          <CreateProductDialog categories={categories} product={product} products={products}>
             <Button variant="ghost" size="icon" className="h-8 w-8 text-slate-500 hover:text-slate-900 dark:text-slate-400 dark:hover:text-white">
               <Edit2 className="h-4 w-4" />
             </Button>

shop/components/order-wizard.tsx

@@ -139,6 +139,45 @@ export function OrderWizard({
       })
   }, [categories, selections, products, selectedBillingInterval])
 
+  // Product validation errors (requirements and exclusions)
+  const productValidationErrors = useMemo(() => {
+    const errors: string[] = []
+    const selectedProductIds = Object.values(selections)
+      .map(s => s.productId)
+      .filter((id): id is string => !!id)
+
+    selectedProductIds.forEach(prodId => {
+      const prod = products.find(p => p.id === prodId)
+      if (!prod) return
+
+      // Requirements check
+      if (prod.requirements && prod.requirements.length > 0) {
+        const missing = prod.requirements.filter(reqId => !selectedProductIds.includes(reqId))
+        if (missing.length > 0) {
+          const names = missing
+            .map(reqId => products.find(p => p.id === reqId)?.name || reqId)
+            .join(', ')
+          errors.push(`"${prod.name}" benötigt das Produkt: ${names}`)
+        }
+      }
+
+      // Exclusions check
+      if (prod.exclusions && prod.exclusions.length > 0) {
+        const conflicting = prod.exclusions.filter(exId => selectedProductIds.includes(exId))
+        if (conflicting.length > 0) {
+          const names = conflicting
+            .map(exId => products.find(p => p.id === exId)?.name || exId)
+            .join(', ')
+          errors.push(`"${prod.name}" schließt aus: ${names}`)
+        }
+      }
+    })
+
+    return errors
+  }, [selections, products])
+
+  const isNextStepDisabled = !allCategoriesFilled || productValidationErrors.length > 0
+
   // Total price calculations (split by billing interval)
   const { monthlyTotal, oneTimeTotal } = useMemo(() => {
     let monthly = 0
@@ -786,12 +825,18 @@ export function OrderWizard({
                         Bitte aus jeder Pflichtkategorie einen Artikel wählen.
                       </p>
                     )}
+                    {productValidationErrors.map((err, errIdx) => (
+                      <p key={errIdx} className="text-xs text-destructive flex items-center gap-1">
+                        <AlertCircle className="w-3 h-3 text-destructive" />
+                        {err}
+                      </p>
+                    ))}
                   </CardContent>
                   <CardFooter className="flex flex-col gap-2">
                     <Button
                       className="w-full h-12 text-lg"
                       onClick={nextStep}
-                      disabled={!allCategoriesFilled}
+                      disabled={isNextStepDisabled}
                     >
                       Weiter <ChevronRight className="ml-2 w-5 h-5" />
                     </Button>

shop/lib/actions/orders.ts

@@ -104,6 +104,38 @@ export async function submitOrder(params: {
     }
   }
 
+  // Product-level constraints validation
+  const selectedProductIds = Object.values(selections)
+    .map(s => s.productId)
+    .filter((id): id is string => !!id)
+
+  for (const prodId of selectedProductIds) {
+    const prod = dbProducts.find(p => p.id === prodId)
+    if (!prod) continue
+
+    // Product requirements check
+    if (prod.requirements && prod.requirements.length > 0) {
+      const missing = prod.requirements.filter(reqId => !selectedProductIds.includes(reqId))
+      if (missing.length > 0) {
+        const missingNames = missing
+          .map(reqId => dbProducts.find(p => p.id === reqId)?.name || reqId)
+          .join(', ')
+        throw new Error(`Das Produkt "${prod.name}" erfordert die Auswahl von: ${missingNames}.`)
+      }
+    }
+
+    // Product exclusions check
+    if (prod.exclusions && prod.exclusions.length > 0) {
+      const conflicting = prod.exclusions.filter(exId => selectedProductIds.includes(exId))
+      if (conflicting.length > 0) {
+        const conflictingNames = conflicting
+          .map(exId => dbProducts.find(p => p.id === exId)?.name || exId)
+          .join(', ')
+        throw new Error(`Das Produkt "${prod.name}" schließt die gleichzeitige Auswahl von folgenden Produkten aus: ${conflictingNames}.`)
+      }
+    }
+  }
+
   // 1. Snapshots aufbauen
   // Wenn Endkunde vorhanden: dessen Daten einfrieren; sonst Partner-Profil (Fallback)
   const customerSnapshot = buildCustomerSnapshot(customerProfile, endCustomer ?? null)

shop/lib/types.ts

@@ -15,6 +15,8 @@ export type Product = {
   created_at: string
   show_in_kauf?: boolean
   show_in_abo?: boolean
+  requirements?: string[]
+  exclusions?: string[]
 }
 
 export type Category = {

shop/supabase/migrations/20260625143000_add_dependencies_to_products.sql

@@ -0,0 +1,3 @@
+-- Add requirements and exclusions columns to products table
+ALTER TABLE public.products ADD COLUMN IF NOT EXISTS requirements UUID[] DEFAULT '{}';
+ALTER TABLE public.products ADD COLUMN IF NOT EXISTS exclusions UUID[] DEFAULT '{}';