feat(machines) : allow category-only links on machine structure

Enable adding a component, piece, or product to a machine by selecting
only the category (ModelType) without a specific entity. The link
displays a red "À remplir" badge; clicking it reopens the modal
pre-filled with the category so the user can associate an item later.

Backend: entity FKs made nullable on the 3 link tables, modelType FK
added, controller/audit/version/MCP normalization adapted for null
entities.

Frontend: modal accepts category-only confirm, page handles fill mode,
hierarchy builder creates pending nodes, display components show
clickable badge with event propagation through the full hierarchy.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

frontend/app/components/ComponentHierarchy.vue

@@ -12,6 +12,7 @@
         @edit-piece="$emit('edit-piece', $event)"
         @custom-field-update="$emit('custom-field-update', $event)"
         @delete="$emit('delete')"
+        @fill-entity="(linkId, typeId) => $emit('fill-entity', linkId, typeId)"
       />
     </div>
   </div>
@@ -43,5 +44,5 @@ defineProps({
   }
 })
 
-defineEmits(['update', 'edit-piece', 'custom-field-update', 'delete'])
+defineEmits(['update', 'edit-piece', 'custom-field-update', 'delete', 'fill-entity'])
 </script>

frontend/app/components/ComponentItem.vue

@@ -14,7 +14,7 @@
     />
 
     <!-- Component Header -->
-    <div class="flex items-center gap-3 p-3 bg-base-200 rounded-lg cursor-pointer" @click="toggleCollapse">
+    <div class="flex items-center gap-3 p-3 rounded-lg cursor-pointer" :class="component.pendingEntity ? 'bg-error/10 border border-error' : 'bg-base-200'" @click="toggleCollapse">
       <IconLucideChevronRight
         class="w-4 h-4 shrink-0 transition-transform text-base-content/50"
         :class="{ 'rotate-90': !isCollapsed }"
@@ -22,9 +22,18 @@
       />
       <div class="flex-1 min-w-0">
         <div class="flex items-center gap-2 flex-wrap">
-          <h3 class="text-sm font-semibold text-base-content truncate">
+          <h3 class="text-sm font-semibold truncate" :class="component.pendingEntity ? 'text-error' : 'text-base-content'">
             {{ component.name }}
           </h3>
+          <button
+            v-if="component.pendingEntity"
+            type="button"
+            class="badge badge-error badge-sm cursor-pointer hover:badge-outline transition-colors"
+            title="Cliquer pour associer un item"
+            @click.stop="$emit('fill-entity', component.linkId, component.modelTypeId)"
+          >
+            À remplir
+          </button>
           <span v-if="component.reference" class="badge badge-outline badge-xs">{{ component.reference }}</span>
           <span v-if="component.prix" class="badge badge-primary badge-xs">{{ component.prix }}€</span>
         </div>
@@ -54,7 +63,7 @@
     </div>
 
     <!-- Expanded content -->
-    <div v-show="!isCollapsed" class="mt-3 space-y-4 pl-7">
+    <div v-show="!isCollapsed && !component.pendingEntity" class="mt-3 space-y-4 pl-7">
       <!-- Info fields -->
       <div v-if="isEditMode" class="grid grid-cols-1 md:grid-cols-2 gap-3">
         <div class="form-control">
@@ -241,6 +250,7 @@
             @update="updatePiece"
             @edit="editPiece"
             @custom-field-update="updatePieceCustomField"
+            @fill-entity="(linkId, typeId) => $emit('fill-entity', linkId, typeId)"
           />
         </div>
       </div>
@@ -276,6 +286,7 @@
             @update="$emit('update', $event)"
             @edit-piece="$emit('edit-piece', $event)"
             @custom-field-update="$emit('custom-field-update', $event)"
+            @fill-entity="(linkId, typeId) => $emit('fill-entity', linkId, typeId)"
           />
         </div>
       </div>
@@ -317,7 +328,7 @@ const props = defineProps({
   toggleToken: { type: Number, default: 0 },
 })
 
-const emit = defineEmits(['update', 'edit-piece', 'custom-field-update', 'delete'])
+const emit = defineEmits(['update', 'edit-piece', 'custom-field-update', 'delete', 'fill-entity'])
 
 // --- Shared composables ---
 const {

frontend/app/components/PieceItem.vue

@@ -14,7 +14,7 @@
     />
 
     <!-- Piece Header (collapsible, same pattern as ComponentItem) -->
-    <div class="flex items-start justify-between p-4 rounded-lg" :class="piece._emptySlot ? 'bg-error/10 border border-error' : 'bg-base-200'">
+    <div class="flex items-start justify-between p-4 rounded-lg" :class="piece._emptySlot || piece.pendingEntity ? 'bg-error/10 border border-error' : 'bg-base-200'">
       <div class="flex items-start gap-3 flex-1 min-w-0">
         <button
           type="button"
@@ -28,9 +28,18 @@
           <span class="sr-only">{{ isCollapsed ? 'Déplier' : 'Replier' }} la pièce</span>
         </button>
         <div class="flex-1 min-w-0">
-          <h3 class="text-lg font-semibold" :class="{ 'text-error': piece._emptySlot }">
+          <h3 class="text-lg font-semibold" :class="{ 'text-error': piece._emptySlot || piece.pendingEntity }">
             {{ pieceData.name }}
             <span v-if="piece._emptySlot" class="text-sm font-semibold text-error ml-1">— manquant</span>
+            <button
+              v-if="piece.pendingEntity"
+              type="button"
+              class="badge badge-error badge-sm cursor-pointer hover:badge-outline transition-colors ml-1"
+              title="Cliquer pour associer un item"
+              @click.stop="$emit('fill-entity', piece.linkId, piece.modelTypeId)"
+            >
+              À remplir
+            </button>
             <span
               v-if="displayQuantity > 1"
               class="text-sm font-normal text-base-content/60 ml-1"
@@ -77,7 +86,7 @@
       </button>
     </div>
 
-    <div v-show="!isCollapsed" class="space-y-4">
+    <div v-show="!isCollapsed && !piece.pendingEntity" class="space-y-4">
       <div class="p-4 bg-base-100 border border-base-200 rounded-lg">
         <div class="space-y-2 text-sm">
       <div v-if="isEditMode" class="form-control">
@@ -308,7 +317,7 @@ const props = defineProps({
   toggleToken: { type: Number, default: 0 },
 })
 
-const emit = defineEmits(['update', 'edit', 'custom-field-update', 'delete'])
+const emit = defineEmits(['update', 'edit', 'custom-field-update', 'delete', 'fill-entity'])
 
 // --- Local reactive data for editing ---
 const pieceData = reactive({

frontend/app/components/machine/AddEntityToMachineModal.vue

@@ -49,6 +49,12 @@
         />
       </div>
 
+      <div v-if="selectedTypeName && !selectedEntityId && !loadingEntities" class="bg-warning/10 border border-warning rounded-lg p-3 mb-4">
+        <p class="text-sm text-warning font-medium">
+          Aucun item sélectionné — la catégorie sera ajoutée avec le statut "À remplir".
+        </p>
+      </div>
+
       <!-- Summary of selection -->
       <div v-if="selectedEntitySummary" class="bg-base-200 rounded-lg p-3 mb-4">
         <p class="text-sm font-medium">{{ selectedEntitySummary.name }}</p>
@@ -64,10 +70,10 @@
         <button
           type="button"
           class="btn btn-primary"
-          :disabled="!selectedEntityId"
+          :disabled="!selectedTypeId"
           @click="handleConfirm"
         >
-          Ajouter
+          {{ selectedEntityId ? 'Ajouter' : 'Ajouter (catégorie seule)' }}
         </button>
       </div>
     </div>
@@ -90,11 +96,12 @@ type EntityKind = 'component' | 'piece' | 'product'
 const props = defineProps<{
   open: boolean
   entityKind: EntityKind
+  prefillTypeId?: string
 }>()
 
 const emit = defineEmits<{
   close: []
-  confirm: [entityId: string]
+  confirm: [payload: { entityId?: string; modelTypeId: string; modelTypeName: string }]
 }>()
 
 const selectedTypeId = ref('')
@@ -166,6 +173,10 @@ watch(() => props.open, async (isOpen) => {
   if (props.entityKind === 'component') await loadComponentTypes()
   else if (props.entityKind === 'piece') await loadPieceTypes()
   else await loadProductTypes()
+
+  if (props.prefillTypeId) {
+    selectedTypeId.value = props.prefillTypeId
+  }
 })
 
 // Load entities when type changes
@@ -222,8 +233,12 @@ const handleClose = () => {
 }
 
 const handleConfirm = () => {
-  if (!selectedEntityId.value) return
-  emit('confirm', selectedEntityId.value)
+  if (!selectedTypeId.value) return
+  emit('confirm', {
+    entityId: selectedEntityId.value || undefined,
+    modelTypeId: selectedTypeId.value,
+    modelTypeName: selectedTypeName.value,
+  })
   resetState()
   emit('close')
 }

frontend/app/components/machine/MachineComponentsCard.vue

@@ -34,6 +34,7 @@
             :toggle-token="collapseToggleToken"
             @edit-piece="$emit('edit-piece', $event)"
             @delete="$emit('remove-component', component.linkId || component.id)"
+            @fill-entity="(linkId, typeId) => $emit('fill-entity', linkId, typeId)"
           />
         </div>
       </div>
@@ -68,5 +69,6 @@ defineEmits<{
   'custom-field-update': [fieldUpdate: any]
   'add-component': []
   'remove-component': [linkId: string]
+  'fill-entity': [linkId: string, modelTypeId: string]
 }>()
 </script>

frontend/app/components/machine/MachinePiecesCard.vue

@@ -35,6 +35,7 @@
             @update="$emit('update-piece', $event)"
             @edit="$emit('edit-piece', $event)"
             @delete="$emit('remove-piece', piece.linkId || piece.id)"
+            @fill-entity="(linkId, typeId) => $emit('fill-entity', linkId, typeId)"
           />
         </div>
       </div>
@@ -67,5 +68,6 @@ defineEmits<{
   'edit-piece': [piece: any]
   'add-piece': []
   'remove-piece': [linkId: string]
+  'fill-entity': [linkId: string, modelTypeId: string]
 }>()
 </script>

frontend/app/components/machine/MachineProductsCard.vue

@@ -23,14 +23,24 @@
       <div v-if="products.length" class="space-y-3">
         <div
           v-for="product in products"
-          :key="product.id || product.name"
-          class="rounded border border-base-200 bg-base-200/60 p-3 text-sm space-y-2"
+          :key="product.id || product.linkId || product.name"
+          class="rounded border p-3 text-sm space-y-2"
+          :class="product.pendingEntity ? 'border-error bg-error/10' : 'border-base-200 bg-base-200/60'"
         >
           <div class="flex items-center justify-between flex-wrap gap-2">
-            <p class="font-semibold text-base-content">
+            <p class="font-semibold" :class="product.pendingEntity ? 'text-error' : 'text-base-content'">
               {{ product.name }}
             </p>
             <div class="flex items-center gap-2">
+              <button
+                v-if="product.pendingEntity"
+                type="button"
+                class="badge badge-error badge-sm cursor-pointer hover:badge-outline transition-colors"
+                title="Cliquer pour associer un item"
+                @click="$emit('fill-entity', (product.linkId || product.id) as string, product.modelTypeId as string)"
+              >
+                À remplir
+              </button>
               <span v-if="product.groupLabel" class="badge badge-ghost badge-sm">
                 {{ product.groupLabel }}
               </span>
@@ -141,6 +151,9 @@ defineProps<{
     supplierLabel?: string | null
     priceLabel?: string | null
     groupLabel?: string
+    pendingEntity?: boolean
+    modelTypeId?: string | null
+    modelType?: string | null
     documents?: Array<{
       id?: string
       name?: string
@@ -156,6 +169,7 @@ defineProps<{
 defineEmits<{
   'add-product': []
   'remove-product': [linkId: string]
+  'fill-entity': [linkId: string, modelTypeId: string]
 }>()
 
 const previewDocument = ref<any>(null)

frontend/app/composables/useMachineDetailData.ts

@@ -193,6 +193,10 @@ export function useMachineDetailData(machineId: string) {
     removePieceLink,
     addProductLink,
     removeProductLink,
+    addComponentLinkCategoryOnly,
+    addPieceLinkCategoryOnly,
+    addProductLinkCategoryOnly,
+    fillEntityLink,
   } = hierarchy
 
   // Keep the product links proxy in sync with the hierarchy's machineProductLinks
@@ -511,6 +515,8 @@ export function useMachineDetailData(machineId: string) {
     loadMachineData, loadInitialData,
     addComponentLink, removeComponentLink, addPieceLink, removePieceLink,
     addProductLink, removeProductLink, reloadMachineStructure,
+    addComponentLinkCategoryOnly, addPieceLinkCategoryOnly,
+    addProductLinkCategoryOnly, fillEntityLink,
 
     // External
     constructeurs, loadProducts, updateMachineStructure, toast,

frontend/app/composables/useMachineDetailHierarchy.ts

@@ -39,7 +39,7 @@ export function useMachineDetailHierarchy(deps: MachineDetailHierarchyDeps) {
     syncMachineCustomFields,
   } = deps
 
-  const { get, post: apiPost, delete: apiDel } = useApi()
+  const { get, post: apiPost, delete: apiDel, patch: apiPatch } = useApi()
   const toast = useToast()
 
   // ---------------------------------------------------------------------------
@@ -263,6 +263,69 @@ export function useMachineDetailHierarchy(deps: MachineDetailHierarchyDeps) {
     return result
   }
 
+  const addComponentLinkCategoryOnly = async (modelTypeId: string) => {
+    const result: any = await apiPost('/machine_component_links', {
+      machine: `/api/machines/${machineId}`,
+      modelType: `/api/model_types/${modelTypeId}`,
+    })
+    if (result.success) {
+      toast.showSuccess('Catégorie ajoutée — item à remplir')
+      await reloadMachineStructure()
+    } else {
+      toast.showError('Erreur lors de l\'ajout')
+    }
+  }
+
+  const addPieceLinkCategoryOnly = async (modelTypeId: string) => {
+    const result: any = await apiPost('/machine_piece_links', {
+      machine: `/api/machines/${machineId}`,
+      modelType: `/api/model_types/${modelTypeId}`,
+    })
+    if (result.success) {
+      toast.showSuccess('Catégorie ajoutée — item à remplir')
+      await reloadMachineStructure()
+    } else {
+      toast.showError('Erreur lors de l\'ajout')
+    }
+  }
+
+  const addProductLinkCategoryOnly = async (modelTypeId: string) => {
+    const result: any = await apiPost('/machine_product_links', {
+      machine: `/api/machines/${machineId}`,
+      modelType: `/api/model_types/${modelTypeId}`,
+    })
+    if (result.success) {
+      toast.showSuccess('Catégorie ajoutée — item à remplir')
+      await reloadMachineStructure()
+    } else {
+      toast.showError('Erreur lors de l\'ajout')
+    }
+  }
+
+  const fillEntityLink = async (linkId: string, entityId: string, entityKind: string) => {
+    let endpoint = ''
+    let payload: Record<string, string> = {}
+
+    if (entityKind === 'component') {
+      endpoint = `/machine_component_links/${linkId}`
+      payload = { composant: `/api/composants/${entityId}` }
+    } else if (entityKind === 'piece') {
+      endpoint = `/machine_piece_links/${linkId}`
+      payload = { piece: `/api/pieces/${entityId}` }
+    } else {
+      endpoint = `/machine_product_links/${linkId}`
+      payload = { product: `/api/products/${entityId}` }
+    }
+
+    const result: any = await apiPatch(endpoint, payload)
+    if (result.success) {
+      toast.showSuccess('Item associé avec succès')
+      await reloadMachineStructure()
+    } else {
+      toast.showError('Erreur lors de l\'association')
+    }
+  }
+
   const removeProductLink = async (linkId: string) => {
     const result: any = await apiDel(`/machine_product_links/${linkId}`)
     if (result.success) {
@@ -301,6 +364,10 @@ export function useMachineDetailHierarchy(deps: MachineDetailHierarchyDeps) {
     addPieceLink,
     removePieceLink,
     addProductLink,
+    addComponentLinkCategoryOnly,
+    addPieceLinkCategoryOnly,
+    addProductLinkCategoryOnly,
+    fillEntityLink,
     removeProductLink,
   }
 }

frontend/app/composables/useMachineDetailProducts.ts

@@ -103,7 +103,7 @@ export function useMachineDetailProducts(deps: MachineDetailProductsDeps) {
       return {
         id: (resolved?.id as string) || productId || null,
         linkId: (link.id as string) || (typeof link['@id'] === 'string' ? link['@id'].split('/').pop() : null) || null,
-        name: (resolved?.name as string) || 'Produit inconnu',
+        name: (resolved?.name as string) || (link.modelType as AnyRecord)?.name as string || 'Produit inconnu',
         reference: (resolved?.reference as string) || null,
         supplierLabel: resolvedConstructeurs.length
           ? resolvedConstructeurs.map((c) => c.name).filter(Boolean).join(', ') || null
@@ -111,6 +111,9 @@ export function useMachineDetailProducts(deps: MachineDetailProductsDeps) {
         priceLabel: resolved ? getProductPriceLabel(resolved) : null,
         groupLabel: ((resolved?.typeProduct as AnyRecord)?.name as string) || '',
         documents: productId ? (productDocumentsMap.value.get(productId) || []) : [],
+        pendingEntity: (link.pendingEntity as boolean) || false,
+        modelTypeId: (link.modelTypeId as string) || null,
+        modelType: (link.modelType as string) || null,
       }
     })
   })

frontend/app/composables/useMachineHierarchy.ts

@@ -150,6 +150,30 @@ export const buildMachineHierarchyFromLinks = (
   const createPieceNode = (link: AnyRecord, parentComponentName: string | null = null): AnyRecord | null => {
     if (!link || typeof link !== 'object') return null
 
+    // Category-only link (no entity yet)
+    if (link.pendingEntity || (!link.piece && !link.pieceId)) {
+      const machinePieceLinkId = normalizePieceLinkId(link)
+      const mt = (link.modelType || null) as AnyRecord | null
+      return {
+        id: machinePieceLinkId || `pending-${link.id}`,
+        linkId: machinePieceLinkId,
+        name: mt?.name || 'Catégorie sans item',
+        reference: null,
+        prix: null,
+        pendingEntity: true,
+        modelTypeId: link.modelTypeId || mt?.id || null,
+        modelType: mt,
+        pieceId: null,
+        constructeurs: [],
+        documents: [],
+        customFields: [],
+        parentComponentLinkId: link.parentComponentLinkId || link.parentLinkId || null,
+        parentComponentName,
+        machinePieceLinkId,
+        quantity: 1,
+      }
+    }
+
     const appliedPiece = (link.piece && typeof link.piece === 'object' ? link.piece : {}) as AnyRecord
     const originalPiece = (link.originalPiece && typeof link.originalPiece === 'object' ? link.originalPiece : null) as AnyRecord | null
 
@@ -205,6 +229,35 @@ export const buildMachineHierarchyFromLinks = (
   const createComponentNode = (link: AnyRecord): AnyRecord | null => {
     if (!link || typeof link !== 'object') return null
 
+    // Category-only link (no entity yet)
+    if (link.pendingEntity || (!link.composant && !link.composantId)) {
+      const machineComponentLinkId = normalizeComponentLinkId(link)
+      const mt = (link.modelType || null) as AnyRecord | null
+      return {
+        id: machineComponentLinkId || `pending-${link.id}`,
+        linkId: machineComponentLinkId,
+        name: mt?.name || 'Catégorie sans item',
+        reference: null,
+        prix: null,
+        pendingEntity: true,
+        modelTypeId: link.modelTypeId || mt?.id || null,
+        modelType: mt,
+        composantId: null,
+        composant: null,
+        constructeurs: [],
+        documents: [],
+        customFields: [],
+        customFieldValues: [],
+        subComponents: [],
+        pieces: [],
+        overrides: null,
+        parentComponentLinkId: link.parentComponentLinkId || link.parentLinkId || null,
+        machineComponentLinkId,
+        childLinks: [],
+        pieceLinks: [],
+      }
+    }
+
     const appliedComponent = (link.composant && typeof link.composant === 'object' ? link.composant : {}) as AnyRecord
     const originalComponent = (link.originalComposant && typeof link.originalComposant === 'object' ? link.originalComposant : null) as AnyRecord | null
 

frontend/app/pages/machine/[id].vue

@@ -100,6 +100,7 @@
         :is-edit-mode="d.isEditMode.value"
         @add-product="openAddModal('product')"
         @remove-product="async (id) => { await d.removeProductLink(id); refreshVersions() }"
+        @fill-entity="(linkId, typeId) => handleFillEntity(linkId, 'product', typeId)"
       />
 
       <!-- Components Section -->
@@ -115,6 +116,7 @@
         @custom-field-update="d.updatePieceCustomField"
         @add-component="openAddModal('component')"
         @remove-component="async (id) => { await d.removeComponentLink(id); refreshVersions() }"
+        @fill-entity="(linkId, typeId) => handleFillEntity(linkId, 'component', typeId)"
       />
 
       <!-- Machine Pieces Section -->
@@ -129,6 +131,7 @@
         @custom-field-update="d.updatePieceCustomField"
         @add-piece="openAddModal('piece')"
         @remove-piece="async (id) => { await d.removePieceLink(id); refreshVersions() }"
+        @fill-entity="(linkId, typeId) => handleFillEntity(linkId, 'piece', typeId)"
         @toggle-collapse="d.toggleAllPieces"
       />
 
@@ -136,7 +139,8 @@
       <AddEntityToMachineModal
         :open="addModalOpen"
         :entity-kind="addModalKind"
-        @close="addModalOpen = false"
+        :prefill-type-id="fillTypeId"
+        @close="addModalOpen = false; fillLinkId = ''; fillTypeId = ''"
         @confirm="handleAddEntity"
       />
 
@@ -277,6 +281,8 @@ const historyFieldLabels = {
 
 const addModalOpen = ref(false)
 const addModalKind = ref('component')
+const fillLinkId = ref('')
+const fillTypeId = ref('')
 
 const openAddModal = (kind) => {
   addModalKind.value = kind
@@ -288,17 +294,40 @@ const handleRemoveConstructeurLink = (constructeurId) => {
   d.handleMachineConstructeurChange(ids)
 }
 
-const handleAddEntity = async (entityId) => {
-  if (addModalKind.value === 'component') {
-    await d.addComponentLink(entityId)
-  } else if (addModalKind.value === 'piece') {
-    await d.addPieceLink(entityId)
+const handleAddEntity = async (payload) => {
+  const { entityId, modelTypeId } = payload
+
+  if (fillLinkId.value) {
+    await d.fillEntityLink(fillLinkId.value, entityId, addModalKind.value)
+    fillLinkId.value = ''
+    fillTypeId.value = ''
+  } else if (entityId) {
+    if (addModalKind.value === 'component') {
+      await d.addComponentLink(entityId)
+    } else if (addModalKind.value === 'piece') {
+      await d.addPieceLink(entityId)
+    } else {
+      await d.addProductLink(entityId)
+    }
   } else {
-    await d.addProductLink(entityId)
+    if (addModalKind.value === 'component') {
+      await d.addComponentLinkCategoryOnly(modelTypeId)
+    } else if (addModalKind.value === 'piece') {
+      await d.addPieceLinkCategoryOnly(modelTypeId)
+    } else {
+      await d.addProductLinkCategoryOnly(modelTypeId)
+    }
   }
   refreshVersions()
 }
 
+const handleFillEntity = (linkId, entityKind, modelTypeId) => {
+  fillLinkId.value = linkId
+  fillTypeId.value = modelTypeId
+  addModalKind.value = entityKind
+  addModalOpen.value = true
+}
+
 const machineViewTitle = computed(() => {
   return d.isEditMode.value ? 'Modification de la machine' : 'Détails de la machine'
 })

migrations/Version20260403_CategoryOnlyLinks.php

@@ -0,0 +1,94 @@
+<?php
+
+declare(strict_types=1);
+
+namespace DoctrineMigrations;
+
+use Doctrine\DBAL\Schema\Schema;
+use Doctrine\Migrations\AbstractMigration;
+
+final class Version20260403_CategoryOnlyLinks extends AbstractMigration
+{
+    public function getDescription(): string
+    {
+        return 'Allow category-only machine links: make entity FKs nullable, add modelType FK to link tables';
+    }
+
+    public function up(Schema $schema): void
+    {
+        // 1. Make entity FK columns nullable
+        $this->addSql('ALTER TABLE machine_component_links ALTER COLUMN composantid DROP NOT NULL');
+        $this->addSql('ALTER TABLE machine_piece_links ALTER COLUMN pieceid DROP NOT NULL');
+        $this->addSql('ALTER TABLE machine_product_links ALTER COLUMN productid DROP NOT NULL');
+
+        // 2. Add modeltypeid column to all 3 tables
+        $this->addSql('ALTER TABLE machine_component_links ADD COLUMN IF NOT EXISTS modeltypeid VARCHAR(36) DEFAULT NULL');
+        $this->addSql('ALTER TABLE machine_piece_links ADD COLUMN IF NOT EXISTS modeltypeid VARCHAR(36) DEFAULT NULL');
+        $this->addSql('ALTER TABLE machine_product_links ADD COLUMN IF NOT EXISTS modeltypeid VARCHAR(36) DEFAULT NULL');
+
+        // 3. Add FK constraints from modeltypeid to model_types(id) ON DELETE SET NULL
+        $this->addSql(<<<'SQL'
+            DO $$ BEGIN
+              IF NOT EXISTS (
+                SELECT 1 FROM information_schema.table_constraints
+                WHERE constraint_name = 'fk_machine_component_links_modeltype' AND table_name = 'machine_component_links'
+              ) THEN
+                ALTER TABLE machine_component_links ADD CONSTRAINT fk_machine_component_links_modeltype
+                  FOREIGN KEY (modeltypeid) REFERENCES model_types(id) ON DELETE SET NULL;
+              END IF;
+            END $$;
+            SQL);
+
+        $this->addSql(<<<'SQL'
+            DO $$ BEGIN
+              IF NOT EXISTS (
+                SELECT 1 FROM information_schema.table_constraints
+                WHERE constraint_name = 'fk_machine_piece_links_modeltype' AND table_name = 'machine_piece_links'
+              ) THEN
+                ALTER TABLE machine_piece_links ADD CONSTRAINT fk_machine_piece_links_modeltype
+                  FOREIGN KEY (modeltypeid) REFERENCES model_types(id) ON DELETE SET NULL;
+              END IF;
+            END $$;
+            SQL);
+
+        $this->addSql(<<<'SQL'
+            DO $$ BEGIN
+              IF NOT EXISTS (
+                SELECT 1 FROM information_schema.table_constraints
+                WHERE constraint_name = 'fk_machine_product_links_modeltype' AND table_name = 'machine_product_links'
+              ) THEN
+                ALTER TABLE machine_product_links ADD CONSTRAINT fk_machine_product_links_modeltype
+                  FOREIGN KEY (modeltypeid) REFERENCES model_types(id) ON DELETE SET NULL;
+              END IF;
+            END $$;
+            SQL);
+
+        // 4. Add indexes on modeltypeid
+        $this->addSql('CREATE INDEX IF NOT EXISTS idx_machine_component_links_modeltypeid ON machine_component_links (modeltypeid)');
+        $this->addSql('CREATE INDEX IF NOT EXISTS idx_machine_piece_links_modeltypeid ON machine_piece_links (modeltypeid)');
+        $this->addSql('CREATE INDEX IF NOT EXISTS idx_machine_product_links_modeltypeid ON machine_product_links (modeltypeid)');
+    }
+
+    public function down(Schema $schema): void
+    {
+        // Drop indexes
+        $this->addSql('DROP INDEX IF EXISTS idx_machine_component_links_modeltypeid');
+        $this->addSql('DROP INDEX IF EXISTS idx_machine_piece_links_modeltypeid');
+        $this->addSql('DROP INDEX IF EXISTS idx_machine_product_links_modeltypeid');
+
+        // Drop FK constraints
+        $this->addSql('ALTER TABLE machine_component_links DROP CONSTRAINT IF EXISTS fk_machine_component_links_modeltype');
+        $this->addSql('ALTER TABLE machine_piece_links DROP CONSTRAINT IF EXISTS fk_machine_piece_links_modeltype');
+        $this->addSql('ALTER TABLE machine_product_links DROP CONSTRAINT IF EXISTS fk_machine_product_links_modeltype');
+
+        // Drop modeltypeid columns
+        $this->addSql('ALTER TABLE machine_component_links DROP COLUMN IF EXISTS modeltypeid');
+        $this->addSql('ALTER TABLE machine_piece_links DROP COLUMN IF EXISTS modeltypeid');
+        $this->addSql('ALTER TABLE machine_product_links DROP COLUMN IF EXISTS modeltypeid');
+
+        // Restore NOT NULL on entity FK columns
+        $this->addSql('ALTER TABLE machine_component_links ALTER COLUMN composantid SET NOT NULL');
+        $this->addSql('ALTER TABLE machine_piece_links ALTER COLUMN pieceid SET NOT NULL');
+        $this->addSql('ALTER TABLE machine_product_links ALTER COLUMN productid SET NOT NULL');
+    }
+}

src/Controller/MachineStructureController.php

@@ -623,17 +623,21 @@ class MachineStructureController extends AbstractController
     {
         return array_map(function (MachineComponentLink $link): array {
             $composant  = $link->getComposant();
+            $modelType  = $link->getModelType();
             $parentLink = $link->getParentLink();
 
             return [
                 'id'                    => $link->getId(),
                 'linkId'                => $link->getId(),
                 'machineId'             => $link->getMachine()->getId(),
-                'composantId'           => $composant->getId(),
-                'composant'             => $this->normalizeComposant($composant),
+                'composantId'           => $composant?->getId(),
+                'composant'             => $composant ? $this->normalizeComposant($composant) : null,
+                'modelTypeId'           => $modelType?->getId(),
+                'modelType'             => $modelType ? $this->normalizeModelType($modelType) : null,
+                'pendingEntity'         => null === $composant,
                 'parentLinkId'          => $parentLink?->getId(),
                 'parentComponentLinkId' => $parentLink?->getId(),
-                'parentComponentId'     => $parentLink?->getComposant()->getId(),
+                'parentComponentId'     => $parentLink?->getComposant()?->getId(),
                 'overrides'             => $this->normalizeOverrides($link),
                 'childLinks'            => [],
                 'pieceLinks'            => [],
@@ -645,19 +649,23 @@ class MachineStructureController extends AbstractController
     {
         return array_map(function (MachinePieceLink $link): array {
             $piece      = $link->getPiece();
+            $modelType  = $link->getModelType();
             $parentLink = $link->getParentLink();
 
             return [
                 'id'                    => $link->getId(),
                 'linkId'                => $link->getId(),
                 'machineId'             => $link->getMachine()->getId(),
-                'pieceId'               => $piece->getId(),
-                'piece'                 => $this->normalizePiece($piece),
+                'pieceId'               => $piece?->getId(),
+                'piece'                 => $piece ? $this->normalizePiece($piece) : null,
+                'modelTypeId'           => $modelType?->getId(),
+                'modelType'             => $modelType ? $this->normalizeModelType($modelType) : null,
+                'pendingEntity'         => null === $piece,
                 'parentLinkId'          => $parentLink?->getId(),
                 'parentComponentLinkId' => $parentLink?->getId(),
-                'parentComponentId'     => $parentLink?->getComposant()->getId(),
+                'parentComponentId'     => $parentLink?->getComposant()?->getId(),
                 'overrides'             => $this->normalizeOverrides($link),
-                'quantity'              => $this->resolvePieceQuantity($link),
+                'quantity'              => $piece ? $this->resolvePieceQuantity($link) : 1,
             ];
         }, $links);
     }
@@ -665,13 +673,16 @@ class MachineStructureController extends AbstractController
     private function resolvePieceQuantity(MachinePieceLink $link): int
     {
         $parentLink = $link->getParentLink();
+        $piece      = $link->getPiece();
 
-        if (!$parentLink) {
+        if (!$parentLink || !$piece) {
             return $link->getQuantity();
         }
 
         $composant = $parentLink->getComposant();
-        $piece     = $link->getPiece();
+        if (!$composant) {
+            return $link->getQuantity();
+        }
 
         foreach ($composant->getPieceSlots() as $slot) {
             if ($slot->getSelectedPiece()?->getId() === $piece->getId()) {
@@ -685,14 +696,18 @@ class MachineStructureController extends AbstractController
     private function normalizeProductLinks(array $links): array
     {
         return array_map(function (MachineProductLink $link): array {
-            $product = $link->getProduct();
+            $product   = $link->getProduct();
+            $modelType = $link->getModelType();
 
             return [
                 'id'                    => $link->getId(),
                 'linkId'                => $link->getId(),
                 'machineId'             => $link->getMachine()->getId(),
-                'productId'             => $product->getId(),
-                'product'               => $this->normalizeProduct($product),
+                'productId'             => $product?->getId(),
+                'product'               => $product ? $this->normalizeProduct($product) : null,
+                'modelTypeId'           => $modelType?->getId(),
+                'modelType'             => $modelType ? $this->normalizeModelType($modelType) : null,
+                'pendingEntity'         => null === $product,
                 'parentLinkId'          => $link->getParentLink()?->getId(),
                 'parentComponentLinkId' => $link->getParentComponentLink()?->getId(),
                 'parentPieceLinkId'     => $link->getParentPieceLink()?->getId(),

src/Entity/MachineComponentLink.php

@@ -46,8 +46,12 @@ class MachineComponentLink
     private Machine $machine;
 
     #[ORM\ManyToOne(targetEntity: Composant::class, inversedBy: 'machineLinks')]
-    #[ORM\JoinColumn(name: 'composantId', referencedColumnName: 'id', nullable: false, onDelete: 'CASCADE')]
-    private Composant $composant;
+    #[ORM\JoinColumn(name: 'composantId', referencedColumnName: 'id', nullable: true, onDelete: 'CASCADE')]
+    private ?Composant $composant = null;
+
+    #[ORM\ManyToOne(targetEntity: ModelType::class)]
+    #[ORM\JoinColumn(name: 'modelTypeId', referencedColumnName: 'id', nullable: true, onDelete: 'SET NULL')]
+    private ?ModelType $modelType = null;
 
     #[ORM\ManyToOne(targetEntity: MachineComponentLink::class, inversedBy: 'childLinks')]
     #[ORM\JoinColumn(name: 'parentLinkId', referencedColumnName: 'id', nullable: true, onDelete: 'CASCADE')]
@@ -107,18 +111,30 @@ class MachineComponentLink
         return $this;
     }
 
-    public function getComposant(): Composant
+    public function getComposant(): ?Composant
     {
         return $this->composant;
     }
 
-    public function setComposant(Composant $composant): static
+    public function setComposant(?Composant $composant): static
     {
         $this->composant = $composant;
 
         return $this;
     }
 
+    public function getModelType(): ?ModelType
+    {
+        return $this->modelType;
+    }
+
+    public function setModelType(?ModelType $modelType): static
+    {
+        $this->modelType = $modelType;
+
+        return $this;
+    }
+
     public function getParentLink(): ?MachineComponentLink
     {
         return $this->parentLink;

src/Entity/MachinePieceLink.php

@@ -47,8 +47,12 @@ class MachinePieceLink
     private Machine $machine;
 
     #[ORM\ManyToOne(targetEntity: Piece::class, inversedBy: 'machineLinks')]
-    #[ORM\JoinColumn(name: 'pieceId', referencedColumnName: 'id', nullable: false, onDelete: 'CASCADE')]
-    private Piece $piece;
+    #[ORM\JoinColumn(name: 'pieceId', referencedColumnName: 'id', nullable: true, onDelete: 'CASCADE')]
+    private ?Piece $piece = null;
+
+    #[ORM\ManyToOne(targetEntity: ModelType::class)]
+    #[ORM\JoinColumn(name: 'modelTypeId', referencedColumnName: 'id', nullable: true, onDelete: 'SET NULL')]
+    private ?ModelType $modelType = null;
 
     #[ORM\ManyToOne(targetEntity: MachineComponentLink::class, inversedBy: 'pieceLinks')]
     #[ORM\JoinColumn(name: 'parentLinkId', referencedColumnName: 'id', nullable: true, onDelete: 'CASCADE')]
@@ -98,18 +102,30 @@ class MachinePieceLink
         return $this;
     }
 
-    public function getPiece(): Piece
+    public function getPiece(): ?Piece
     {
         return $this->piece;
     }
 
-    public function setPiece(Piece $piece): static
+    public function setPiece(?Piece $piece): static
     {
         $this->piece = $piece;
 
         return $this;
     }
 
+    public function getModelType(): ?ModelType
+    {
+        return $this->modelType;
+    }
+
+    public function setModelType(?ModelType $modelType): static
+    {
+        $this->modelType = $modelType;
+
+        return $this;
+    }
+
     public function getParentLink(): ?MachineComponentLink
     {
         return $this->parentLink;

src/Entity/MachineProductLink.php

@@ -46,8 +46,12 @@ class MachineProductLink
     private Machine $machine;
 
     #[ORM\ManyToOne(targetEntity: Product::class, inversedBy: 'machineLinks')]
-    #[ORM\JoinColumn(name: 'productId', referencedColumnName: 'id', nullable: false, onDelete: 'CASCADE')]
-    private Product $product;
+    #[ORM\JoinColumn(name: 'productId', referencedColumnName: 'id', nullable: true, onDelete: 'CASCADE')]
+    private ?Product $product = null;
+
+    #[ORM\ManyToOne(targetEntity: ModelType::class)]
+    #[ORM\JoinColumn(name: 'modelTypeId', referencedColumnName: 'id', nullable: true, onDelete: 'SET NULL')]
+    private ?ModelType $modelType = null;
 
     #[ORM\ManyToOne(targetEntity: MachineProductLink::class, inversedBy: 'childLinks')]
     #[ORM\JoinColumn(name: 'parentLinkId', referencedColumnName: 'id', nullable: true, onDelete: 'CASCADE')]
@@ -92,18 +96,30 @@ class MachineProductLink
         return $this;
     }
 
-    public function getProduct(): Product
+    public function getProduct(): ?Product
     {
         return $this->product;
     }
 
-    public function setProduct(Product $product): static
+    public function setProduct(?Product $product): static
     {
         $this->product = $product;
 
         return $this;
     }
 
+    public function getModelType(): ?ModelType
+    {
+        return $this->modelType;
+    }
+
+    public function setModelType(?ModelType $modelType): static
+    {
+        $this->modelType = $modelType;
+
+        return $this;
+    }
+
     public function getParentLink(): ?MachineProductLink
     {
         return $this->parentLink;

src/EventSubscriber/MachineAuditSubscriber.php

@@ -74,18 +74,20 @@ final class MachineAuditSubscriber extends AbstractAuditSubscriber
         foreach ($entity->getComponentLinks() as $link) {
             $componentLinks[] = [
                 'id'            => $link->getId(),
-                'composantId'   => $link->getComposant()->getId(),
-                'composantName' => $link->getComposant()->getName(),
+                'composantId'   => $link->getComposant()?->getId(),
+                'composantName' => $link->getComposant()?->getName(),
+                'modelTypeId'   => $link->getModelType()?->getId(),
             ];
         }
 
         $pieceLinks = [];
         foreach ($entity->getPieceLinks() as $link) {
             $pieceLinks[] = [
-                'id'        => $link->getId(),
-                'pieceId'   => $link->getPiece()->getId(),
-                'pieceName' => $link->getPiece()->getName(),
-                'quantity'  => $link->getQuantity(),
+                'id'          => $link->getId(),
+                'pieceId'     => $link->getPiece()?->getId(),
+                'pieceName'   => $link->getPiece()?->getName(),
+                'quantity'    => $link->getQuantity(),
+                'modelTypeId' => $link->getModelType()?->getId(),
             ];
         }
 
@@ -93,8 +95,9 @@ final class MachineAuditSubscriber extends AbstractAuditSubscriber
         foreach ($entity->getProductLinks() as $link) {
             $productLinks[] = [
                 'id'          => $link->getId(),
-                'productId'   => $link->getProduct()->getId(),
-                'productName' => $link->getProduct()->getName(),
+                'productId'   => $link->getProduct()?->getId(),
+                'productName' => $link->getProduct()?->getName(),
+                'modelTypeId' => $link->getModelType()?->getId(),
             ];
         }
 
@@ -187,8 +190,8 @@ final class MachineAuditSubscriber extends AbstractAuditSubscriber
                 'machine'   => $entity->getMachine(),
                 'diffKey'   => $action.'Component',
                 'diffValue' => [
-                    'id'   => $entity->getComposant()->getId(),
-                    'name' => $entity->getComposant()->getName(),
+                    'id'   => $entity->getComposant()?->getId() ?? $entity->getModelType()?->getId(),
+                    'name' => $entity->getComposant()?->getName() ?? $entity->getModelType()?->getName() ?? 'Catégorie seule',
                 ],
             ];
         }
@@ -198,8 +201,8 @@ final class MachineAuditSubscriber extends AbstractAuditSubscriber
                 'machine'   => $entity->getMachine(),
                 'diffKey'   => $action.'Piece',
                 'diffValue' => [
-                    'id'   => $entity->getPiece()->getId(),
-                    'name' => $entity->getPiece()->getName(),
+                    'id'   => $entity->getPiece()?->getId() ?? $entity->getModelType()?->getId(),
+                    'name' => $entity->getPiece()?->getName() ?? $entity->getModelType()?->getName() ?? 'Catégorie seule',
                 ],
             ];
         }
@@ -209,8 +212,8 @@ final class MachineAuditSubscriber extends AbstractAuditSubscriber
                 'machine'   => $entity->getMachine(),
                 'diffKey'   => $action.'Product',
                 'diffValue' => [
-                    'id'   => $entity->getProduct()->getId(),
-                    'name' => $entity->getProduct()->getName(),
+                    'id'   => $entity->getProduct()?->getId() ?? $entity->getModelType()?->getId(),
+                    'name' => $entity->getProduct()?->getName() ?? $entity->getModelType()?->getName() ?? 'Catégorie seule',
                 ],
             ];
         }

src/Mcp/Tool/Machine/MachineStructureTool.php

@@ -164,11 +164,11 @@ class MachineStructureTool
                 'id'                    => $link->getId(),
                 'linkId'                => $link->getId(),
                 'machineId'             => $link->getMachine()->getId(),
-                'composantId'           => $composant->getId(),
-                'composant'             => $this->normalizeComposant($composant),
+                'composantId'           => $composant?->getId(),
+                'composant'             => $composant ? $this->normalizeComposant($composant) : null,
                 'parentLinkId'          => $parentLink?->getId(),
                 'parentComponentLinkId' => $parentLink?->getId(),
-                'parentComponentId'     => $parentLink?->getComposant()->getId(),
+                'parentComponentId'     => $parentLink?->getComposant()?->getId(),
                 'overrides'             => $this->normalizeOverrides($link),
                 'childLinks'            => [],
                 'pieceLinks'            => [],
@@ -189,13 +189,13 @@ class MachineStructureTool
                 'id'                    => $link->getId(),
                 'linkId'                => $link->getId(),
                 'machineId'             => $link->getMachine()->getId(),
-                'pieceId'               => $piece->getId(),
-                'piece'                 => $this->normalizePiece($piece),
+                'pieceId'               => $piece?->getId(),
+                'piece'                 => $piece ? $this->normalizePiece($piece) : null,
                 'parentLinkId'          => $parentLink?->getId(),
                 'parentComponentLinkId' => $parentLink?->getId(),
-                'parentComponentId'     => $parentLink?->getComposant()->getId(),
+                'parentComponentId'     => $parentLink?->getComposant()?->getId(),
                 'overrides'             => $this->normalizeOverrides($link),
-                'quantity'              => $this->resolvePieceQuantity($link),
+                'quantity'              => $piece ? $this->resolvePieceQuantity($link) : 1,
             ];
         }, $links);
     }

src/Service/EntityVersionService.php

@@ -869,22 +869,25 @@ final class EntityVersionService
             $snapshot['componentLinks'] = [];
             foreach ($entity->getComponentLinks() as $link) {
                 $snapshot['componentLinks'][] = [
-                    'id'            => $link->getId(), 'composantId' => $link->getComposant()->getId(),
-                    'composantName' => $link->getComposant()->getName(),
+                    'id'            => $link->getId(), 'composantId' => $link->getComposant()?->getId(),
+                    'composantName' => $link->getComposant()?->getName(),
+                    'modelTypeId'   => $link->getModelType()?->getId(),
                 ];
             }
             $snapshot['pieceLinks'] = [];
             foreach ($entity->getPieceLinks() as $link) {
                 $snapshot['pieceLinks'][] = [
-                    'id'        => $link->getId(), 'pieceId' => $link->getPiece()->getId(),
-                    'pieceName' => $link->getPiece()->getName(), 'quantity' => $link->getQuantity(),
+                    'id'          => $link->getId(), 'pieceId' => $link->getPiece()?->getId(),
+                    'pieceName'   => $link->getPiece()?->getName(), 'quantity' => $link->getQuantity(),
+                    'modelTypeId' => $link->getModelType()?->getId(),
                 ];
             }
             $snapshot['productLinks'] = [];
             foreach ($entity->getProductLinks() as $link) {
                 $snapshot['productLinks'][] = [
-                    'id'          => $link->getId(), 'productId' => $link->getProduct()->getId(),
-                    'productName' => $link->getProduct()->getName(),
+                    'id'          => $link->getId(), 'productId' => $link->getProduct()?->getId(),
+                    'productName' => $link->getProduct()?->getName(),
+                    'modelTypeId' => $link->getModelType()?->getId(),
                 ];
             }
         }