10.

Implementation
A partner, not just software
HexDive Technologies' local team handles setup, data migration, training and ongoing support — in Sinhala, Tamil and English. [confirm]

1
Discovery
Map your network, products and processes.

2
Configuration
Set up depots, pricing, schemes, routes and users.

3
Migration & training
Move your data and train every team.

4
Go-live & support
Dedicated account manager and local support desk.

Distribution/Features/ExpenseCategory/ExpenseCategoryController.cs

@@ -0,0 +1,29 @@
+using Microsoft.AspNetCore.Authorization;
+using Microsoft.AspNetCore.Mvc;
+
+namespace Distribution.Features.ExpenseCategory;
+
+[ApiController]
+[Route("api/expense-categories")]
+public class ExpenseCategoryController(ExpenseCategoryService service) : ControllerBase
+{
+    [HttpGet]
+    [Authorize("expense.view")]
+    public async Task<IActionResult> Tree() => Ok(await service.GetTreeAsync());
+
+    [HttpPost]
+    [Authorize("expense.manage_categories")]
+    public async Task<IActionResult> Create(CreateExpenseCategoryRequest request, CancellationToken ct)
+    {
+        try { return Ok(await service.CreateAsync(request, ct)); }
+        catch (InvalidOperationException ex) { return BadRequest(new { error = ex.Message }); }
+    }
+
+    [HttpPut("{id:guid}")]
+    [Authorize("expense.manage_categories")]
+    public async Task<IActionResult> Update(Guid id, UpdateExpenseCategoryRequest request, CancellationToken ct)
+    {
+        var result = await service.UpdateAsync(id, request, ct);
+        return result is null ? NotFound() : Ok(result);
+    }
+}

Distribution/Features/ExpenseCategory/ExpenseCategoryDTOs.cs

@@ -0,0 +1,19 @@
+namespace Distribution.Features.ExpenseCategory;
+
+public record ExpenseCategoryResponse(
+    Guid Id,
+    string Name,
+    string? Code,
+    Guid? ParentCategoryId,
+    bool IsActive,
+    List<ExpenseCategoryResponse> Children);
+
+public record CreateExpenseCategoryRequest(
+    string Name,
+    string? Code,
+    Guid? ParentCategoryId);
+
+public record UpdateExpenseCategoryRequest(
+    string Name,
+    string? Code,
+    bool IsActive);

Distribution/Features/ExpenseCategory/ExpenseCategoryRepository.cs

@@ -0,0 +1,19 @@
+using Distribution.Data;
+using Microsoft.EntityFrameworkCore;
+
+namespace Distribution.Features.ExpenseCategory;
+
+public class ExpenseCategoryRepository(AppDBContext context) : IExpenseCategoryRepository
+{
+    public async Task<Models.ExpenseCategory?> GetByIdAsync(Guid id) =>
+        await context.ExpenseCategories.FirstOrDefaultAsync(c => c.Id == id);
+
+    public async Task<List<Models.ExpenseCategory>> GetAllAsync() =>
+        await context.ExpenseCategories.OrderBy(c => c.FK_ParentCategoryId).ThenBy(c => c.Name).ToListAsync();
+
+    public async Task AddAsync(Models.ExpenseCategory entity) =>
+        await context.ExpenseCategories.AddAsync(entity);
+
+    public void Update(Models.ExpenseCategory entity) =>
+        context.ExpenseCategories.Update(entity);
+}

Distribution/Features/ExpenseCategory/ExpenseCategoryService.cs

@@ -0,0 +1,64 @@
+using Distribution.Infra.UoW;
+
+namespace Distribution.Features.ExpenseCategory;
+
+public class ExpenseCategoryService(IExpenseCategoryRepository repo, IUnitOfWork uow)
+{
+    public async Task<List<ExpenseCategoryResponse>> GetTreeAsync()
+    {
+        var all = await repo.GetAllAsync();
+        var byParent = all.ToLookup(c => c.FK_ParentCategoryId);
+
+        return all
+            .Where(c => c.FK_ParentCategoryId is null)
+            .Select(c => Map(c, byParent))
+            .ToList();
+    }
+
+    private static ExpenseCategoryResponse Map(Models.ExpenseCategory c, ILookup<Guid?, Models.ExpenseCategory> byParent) =>
+        new(c.Id, c.Name, c.Code, c.FK_ParentCategoryId, c.IsActive,
+            byParent[c.Id].Select(child => Map(child, byParent)).ToList());
+
+    public async Task<ExpenseCategoryResponse> CreateAsync(CreateExpenseCategoryRequest request, CancellationToken ct = default)
+    {
+        if (string.IsNullOrWhiteSpace(request.Name))
+            throw new InvalidOperationException("Name is required");
+
+        if (request.ParentCategoryId is { } parentId)
+        {
+            var parent = await repo.GetByIdAsync(parentId)
+                ?? throw new InvalidOperationException("Parent category not found");
+            if (parent.FK_ParentCategoryId is not null)
+                throw new InvalidOperationException("Only two levels are allowed — cannot nest under a title");
+        }
+
+        var entity = new Models.ExpenseCategory
+        {
+            Name = request.Name.Trim(),
+            Code = string.IsNullOrWhiteSpace(request.Code) ? null : request.Code.Trim(),
+            FK_ParentCategoryId = request.ParentCategoryId
+        };
+
+        await uow.BeginAsync(ct);
+        try { await repo.AddAsync(entity); await uow.CommitAsync(ct); }
+        catch { await uow.RollbackAsync(ct); throw; }
+
+        return new ExpenseCategoryResponse(entity.Id, entity.Name, entity.Code, entity.FK_ParentCategoryId, entity.IsActive, []);
+    }
+
+    public async Task<ExpenseCategoryResponse?> UpdateAsync(Guid id, UpdateExpenseCategoryRequest request, CancellationToken ct = default)
+    {
+        var entity = await repo.GetByIdAsync(id);
+        if (entity is null) return null;
+
+        entity.Name = request.Name.Trim();
+        entity.Code = string.IsNullOrWhiteSpace(request.Code) ? null : request.Code.Trim();
+        entity.IsActive = request.IsActive;
+
+        await uow.BeginAsync(ct);
+        try { repo.Update(entity); await uow.CommitAsync(ct); }
+        catch { await uow.RollbackAsync(ct); throw; }
+
+        return new ExpenseCategoryResponse(entity.Id, entity.Name, entity.Code, entity.FK_ParentCategoryId, entity.IsActive, []);
+    }
+}

Distribution/Features/ExpenseCategory/IExpenseCategoryRepository.cs

@@ -0,0 +1,11 @@
+using Distribution.Models;
+
+namespace Distribution.Features.ExpenseCategory;
+
+public interface IExpenseCategoryRepository
+{
+    Task<Models.ExpenseCategory?> GetByIdAsync(Guid id);
+    Task<List<Models.ExpenseCategory>> GetAllAsync();
+    Task AddAsync(Models.ExpenseCategory entity);
+    void Update(Models.ExpenseCategory entity);
+}