feat: init

apps/web/core/components/labels/label-utils.ts

@@ -0,0 +1,67 @@
+import { extractInstruction } from "@atlaskit/pragmatic-drag-and-drop-hitbox/tree-item";
+import type { IIssueLabel, IPragmaticPayloadLocation, InstructionType, TDropTarget } from "@plane/types";
+
+export type TargetData = {
+  id: string;
+  parentId: string | null;
+  isGroup: boolean;
+  isChild: boolean;
+};
+
+/**
+ * extracts the Payload and translates the instruction for the current dropTarget based on drag and drop payload
+ * @param dropTarget dropTarget for which the instruction is required
+ * @param source the dragging label data that is being dragged on the dropTarget
+ * @param location location includes the data of all the dropTargets the source is being dragged on
+ * @returns Instruction for dropTarget
+ */
+export const getInstructionFromPayload = (
+  dropTarget: TDropTarget,
+  source: TDropTarget,
+  location: IPragmaticPayloadLocation
+): InstructionType | undefined => {
+  const dropTargetData = dropTarget?.data as TargetData;
+  const sourceData = source?.data as TargetData;
+
+  const allDropTargets = location?.current?.dropTargets;
+
+  // if all the dropTargets are greater than 1 meaning the source is being dragged on a group and its child at the same time
+  // and also if the dropTarget in question is also a group then, it should be a child of the current Droptarget
+  if (allDropTargets?.length > 1 && dropTargetData?.isGroup) return "make-child";
+
+  if (!dropTargetData || !sourceData) return undefined;
+
+  let instruction = extractInstruction(dropTargetData)?.type;
+
+  // If the instruction is blocked then set an instruction based on if dropTarget it is a child or not
+  if (instruction === "instruction-blocked") {
+    instruction = dropTargetData.isChild ? "reorder-above" : "make-child";
+  }
+
+  // if source that is being dragged is a group. A group cannon be a child of any other label,
+  // hence if current instruction is to be a child of dropTarget then reorder-above instead
+  if (instruction === "make-child" && sourceData.isGroup) instruction = "reorder-above";
+
+  return instruction;
+};
+
+/**
+ * This provides a boolean to indicate if the label can be dropped onto the droptarget
+ * @param source
+ * @param label
+ * @param isCurrentChild if the dropTarget is a child
+ * @returns
+ */
+export const getCanDrop = (source: TDropTarget, label: IIssueLabel | undefined, isCurrentChild: boolean) => {
+  const sourceData = source?.data;
+
+  if (!sourceData) return false;
+
+  // a label cannot be dropped on to itself and it's parent cannon be dropped on the child
+  if (sourceData.id === label?.id || sourceData.id === label?.parent) return false;
+
+  // if current dropTarget is a child and the label being dropped is a group then don't enable drop
+  if (isCurrentChild && sourceData.isGroup) return false;
+
+  return true;
+};