reverse pedigree

client/src/utils/pedigreeHelpers.js

@@ -180,4 +180,48 @@ export const getPedigreeCompleteness = (treeData, targetGenerations = 5) => {
   const expectedTotal = Math.pow(2, targetGenerations) - 1
   const actualCount = countAncestors(treeData)
   return Math.min(100, Math.round((actualCount / expectedTotal) * 100))
+}
+
+/**
+ * Transform API descendant data to react-d3-tree format
+ * @param {Object} dog - Dog object from API with nested offspring array
+ * @param {number} maxGenerations - Maximum generations to display (default 3)
+ * @returns {Object} Tree data in react-d3-tree format
+ */
+export const transformDescendantData = (dog, maxGenerations = 3) => {
+  if (!dog) return null
+
+  const buildTree = (dogData, generation = 0) => {
+    if (!dogData || generation >= maxGenerations) {
+      return null
+    }
+
+    const node = {
+      name: dogData.name || 'Unknown',
+      attributes: {
+        id: dogData.id,
+        sex: dogData.sex,
+        registration: dogData.registration_number || '',
+        birth_year: dogData.birth_date ? new Date(dogData.birth_date).getFullYear() : ''
+      },
+      children: []
+    }
+
+    if (dogData.offspring && dogData.offspring.length > 0) {
+      dogData.offspring.forEach(child => {
+        const childNode = buildTree(child, generation + 1)
+        if (childNode) {
+          node.children.push(childNode)
+        }
+      })
+    }
+
+    if (node.children.length === 0) {
+      delete node.children
+    }
+
+    return node
+  }
+
+  return buildTree(dog)
 }