Coverage Summary for Class: DeleteCategoryUseCase (com.georgeci.moneysurfer.domain.usecase)

 package com.georgeci.moneysurfer.domain.usecase
 
 import com.georgeci.moneysurfer.domain.model.Category
 import com.georgeci.moneysurfer.domain.model.CategoryTree
 import com.georgeci.moneysurfer.domain.primitives.CategoryId
 import com.georgeci.moneysurfer.domain.repositories.CategoryRepository
 import kotlinx.coroutines.flow.first
 import org.koin.core.annotation.Single
 
 /**
  * What a delete removed, in enough detail to undo it: the category itself plus its children
  * **as they were before**, still pointing at the deleted parent.
  */
 data class CategoryDeletion(
     val category: Category,
     val reparentedChildren: List<Category>,
 )
 
 @Single
 class DeleteCategoryUseCase(
     private val categoryRepository: CategoryRepository,
 ) {
 
     /**
      * Deletes the category and returns what was removed so callers can offer an Undo.
      *
      * Deleting a parent moves its children up to the root rather than removing them with it —
      * the alternative, refusing the delete while children exist, makes the user dismantle a
      * tree from the bottom for no gain. The reparenting also has to happen *first*: the
      * `parentId` foreign key declares no cascade, so deleting a row that still has children
      * would be rejected by SQLite.
      */
     suspend operator fun invoke(id: CategoryId): CategoryDeletion? {
         val existing = categoryRepository.getById(id) ?: return null
         val children = CategoryTree.childrenOf(categoryRepository.getAll().first(), id)
         children.forEach { child ->
             categoryRepository.update(child.copy(parentId = null))
         }
         categoryRepository.delete(id)
         return CategoryDeletion(category = existing, reparentedChildren = children)
     }
 }