max id calculation

apps/dashboard/pkg/migration/conversion/testdata/migrated_dashboards_output/v1beta1-mig-v16.span_zero_demo.v42.v0alpha1.json

@@ -77,7 +77,7 @@
           "x": 0,
           "y": 0
         },
-        "id": 23,
+        "id": 24,
         "panels": [],
         "targets": [
           {

apps/dashboard/pkg/migration/schemaversion/v16.go

@@ -46,7 +46,8 @@ func upgradeToGridLayout(dashboard map[string]interface{}) {
 	widthFactor := gridColumnCount / 12.0
 
 	// Find max panel ID (lines 1014-1021 in TS)
-	maxPanelID := getMaxPanelID(rows)
+	// Also check top-level panels which may have been assigned IDs by ensurePanelsHaveUniqueIds
+	maxPanelID := getMaxPanelID(dashboard, rows)
 	nextRowID := maxPanelID + 1
 
 	// Match frontend: dashboard.panels already exists with top-level panels
@@ -269,10 +270,25 @@ func (r *rowArea) getPanelPosition(panelHeight int, panelWidth int) map[string]i
 	return r.getPanelPosition(panelHeight, panelWidth)
 }
 
-func getMaxPanelID(rows []interface{}) int {
+func getMaxPanelID(dashboard map[string]interface{}, rows []interface{}) int {
 	maxID := 0
 	hasValidID := false
 
+	// Check top-level panels first (these may have been assigned IDs by ensurePanelsHaveUniqueIds)
+	if panels, ok := dashboard["panels"].([]interface{}); ok {
+		for _, panelInterface := range panels {
+			if panel, ok := panelInterface.(map[string]interface{}); ok {
+				if id := GetIntValue(panel, "id", 0); id > 0 {
+					hasValidID = true
+					if id > maxID {
+						maxID = id
+					}
+				}
+			}
+		}
+	}
+
+	// Also check panels inside rows
 	for _, rowInterface := range rows {
 		if row, ok := rowInterface.(map[string]interface{}); ok {
 			if panels, ok := row["panels"].([]interface{}); ok {

apps/dashboard/pkg/migration/testdata/output/latest_version/v16.span_zero_demo.v42.json

@@ -71,7 +71,7 @@
         "x": 0,
         "y": 0
       },
-      "id": 23,
+      "id": 24,
       "panels": [],
       "targets": [
         {

apps/dashboard/pkg/migration/testdata/output/single_version/v16.span_zero_demo.v16.json

@@ -51,7 +51,7 @@
         "x": 0,
         "y": 0
       },
-      "id": 23,
+      "id": 24,
       "panels": [],
       "title": "Application Service",
       "type": "row"

public/app/features/dashboard/state/DashboardMigrator.ts

@@ -816,14 +816,17 @@ export class DashboardMigrator {
     let yPos = 0;
     const widthFactor = GRID_COLUMN_COUNT / 12;
 
-    const maxPanelId =
-      max(
-        flattenDeep(
-          map(old.rows, (row) => {
-            return map(row.panels, 'id');
-          })
-        ).filter((id) => id != null)
-      ) || 0;
+    // Find max panel ID from both rows and existing top-level panels
+    // Top-level panels may have been assigned IDs by ensurePanelsHaveUniqueIds
+    const rowPanelIds = flattenDeep(
+      map(old.rows, (row) => {
+        return map(row.panels, 'id');
+      })
+    ).filter((id) => id != null);
+
+    const topLevelPanelIds = map(this.dashboard.panels, 'id').filter((id) => id != null);
+
+    const maxPanelId = max([...rowPanelIds, ...topLevelPanelIds]) || 0;
     let nextRowId = maxPanelId + 1;
 
     if (!old.rows) {