Added an API to get purchase invoice overview

Marco.Pms.Services/Controllers/DashboardController.cs

@@ -1225,7 +1225,11 @@ namespace Marco.Pms.Services.Controllers
         {
             // Correlation ID pattern for distributed tracing (if you use one)
             var correlationId = HttpContext.TraceIdentifier;
-
+            if (tenantId == Guid.Empty)
+            {
+                _logger.LogWarning("Invalid request: TenantId is empty on progression endpoint");
+                return BadRequest(ApiResponse<object>.ErrorResponse("Invalid TenantId", "Provided Invalid TenantId", 400));
+            }
             _logger.LogInfo("Started GetCollectionOverviewAsync. CorrelationId: {CorrelationId}, ProjectId: {ProjectId}", correlationId, projectId ?? Guid.Empty);
 
             try
@@ -1455,6 +1459,156 @@ namespace Marco.Pms.Services.Controllers
             }
         }
 
+        [HttpGet("purchase-invoice-overview")]
+        public async Task<IActionResult> GetPurchaseInvoiceOverview()
+        {
+            // Correlation id for tracing this request across services/logs.
+            var correlationId = HttpContext.TraceIdentifier;
+
+            _logger.LogInfo("GetPurchaseInvoiceOverview started. TenantId: {TenantId}, CorrelationId: {CorrelationId}", tenantId, correlationId);
+
+            // Basic guard: invalid tenant.
+            if (tenantId == Guid.Empty)
+            {
+                _logger.LogWarning("GetPurchaseInvoiceOverview rejected due to empty TenantId. CorrelationId: {CorrelationId}", correlationId);
+
+                return BadRequest(ApiResponse<object>.ErrorResponse("Invalid TenantId", "The tenant identifier provided is invalid or missing.", 400));
+            }
+
+            try
+            {
+                // Fetch current employee context (if needed for authorization/audit).
+                var loggedInEmployee = await _userHelper.GetCurrentEmployeeAsync();
+
+                // Run project queries in parallel to reduce latency.
+                var infraProjectTask = GetInfraProjectsAsync(tenantId);
+                var serviceProjectTask = GetServiceProjectsAsync(tenantId);
+
+                await Task.WhenAll(infraProjectTask, serviceProjectTask);
+
+                var projects = infraProjectTask.Result
+                    .Union(serviceProjectTask.Result)
+                    .ToList();
+
+                _logger.LogDebug("GetPurchaseInvoiceOverview loaded projects. Count: {ProjectCount}, TenantId: {TenantId}, CorrelationId: {CorrelationId}", projects.Count, tenantId, correlationId);
+
+                // Query purchase invoices for the tenant.
+                var purchaseInvoices = await _context.PurchaseInvoiceDetails
+                    .Include(pid => pid.Supplier)
+                    .Include(pid => pid.Status)
+                    .AsNoTracking()
+                    .Where(pid => pid.TenantId == tenantId && pid.IsActive)
+                    .ToListAsync();
+
+                _logger.LogInfo("GetPurchaseInvoiceOverview loaded invoices. InvoiceCount: {InvoiceCount}, TenantId: {TenantId}, CorrelationId: {CorrelationId}",
+                    purchaseInvoices.Count, tenantId, correlationId);
+
+                if (!purchaseInvoices.Any())
+                {
+                    // No invoices is not an error; return an empty but well-structured overview.
+                    _logger.LogInfo("GetPurchaseInvoiceOverview: No active purchase invoices found. TenantId: {TenantId}, CorrelationId: {CorrelationId}", tenantId, correlationId);
+
+                    var emptyResponse = new
+                    {
+                        TotalInvoices = 0,
+                        TotalValue = 0m,
+                        AverageValue = 0m,
+                        StatusBreakdown = Array.Empty<object>(),
+                        ProjectBreakdown = Array.Empty<object>(),
+                        TopSupplier = (object?)null
+                    };
+
+                    return Ok(ApiResponse<object>.SuccessResponse(
+                        emptyResponse,
+                        "No active purchase invoices found for the specified tenant.",
+                        StatusCodes.Status200OK));
+                }
+
+                var totalInvoices = purchaseInvoices.Count;
+                var totalValue = purchaseInvoices.Sum(pid => pid.BaseAmount);
+
+                // Guard against divide-by-zero (in case BaseAmount is all zero).
+                var averageValue = totalInvoices > 0
+                    ? totalValue / totalInvoices
+                    : 0;
+
+                // Status-wise aggregation
+                var statusBreakdown = purchaseInvoices
+                    .Where(pid => pid.Status != null)
+                    .GroupBy(pid => pid.StatusId)
+                    .Select(g => new
+                    {
+                        Id = g.Key,
+                        Name = g.First().Status!.DisplayName,
+                        Count = g.Count(),
+                        TotalValue = g.Sum(pid => pid.BaseAmount),
+                        Percentage = totalValue > 0
+                            ? Math.Round(g.Sum(pid => pid.BaseAmount) / totalValue * 100, 2)
+                            : 0
+                    })
+                    .OrderByDescending(x => x.TotalValue)
+                    .ToList();
+
+                // Project-wise aggregation (top 3 by value)
+                var projectBreakdown = purchaseInvoices
+                    .GroupBy(pid => pid.ProjectId)
+                    .Select(g => new
+                    {
+                        Id = g.Key,
+                        Name = projects.FirstOrDefault(p => p.Id == g.Key)?.Name ?? "Unknown Project",
+                        Count = g.Count(),
+                        TotalValue = g.Sum(pid => pid.BaseAmount),
+                        Percentage = totalValue > 0
+                            ? Math.Round(g.Sum(pid => pid.BaseAmount) / totalValue * 100, 2)
+                            : 0
+                    })
+                    .OrderByDescending(pid => pid.TotalValue)
+                    .Take(3)
+                    .ToList();
+
+                // Top supplier by total value
+                var supplierBreakdown = purchaseInvoices
+                    .Where(pid => pid.Supplier != null)
+                    .GroupBy(pid => pid.SupplierId)
+                    .Select(g => new
+                    {
+                        Id = g.Key,
+                        Name = g.First().Supplier!.Name,
+                        Count = g.Count(),
+                        TotalValue = g.Sum(pid => pid.BaseAmount),
+                        Percentage = totalValue > 0
+                            ? Math.Round(g.Sum(pid => pid.BaseAmount) / totalValue * 100, 2)
+                            : 0
+                    })
+                    .OrderByDescending(pid => pid.TotalValue)
+                    .FirstOrDefault();
+
+                var response = new
+                {
+                    TotalInvoices = totalInvoices,
+                    TotalValue = Math.Round(totalValue, 2),
+                    AverageValue = Math.Round(averageValue, 2),
+                    StatusBreakdown = statusBreakdown,
+                    ProjectBreakdown = projectBreakdown,
+                    TopSupplier = supplierBreakdown
+                };
+
+                _logger.LogInfo("GetPurchaseInvoiceOverview completed successfully. TenantId: {TenantId}, TotalInvoices: {TotalInvoices}, TotalValue: {TotalValue}, CorrelationId: {CorrelationId}",
+                    tenantId, totalInvoices, totalValue, correlationId);
+
+                return Ok(ApiResponse<object>.SuccessResponse(response, "Purchase invoice overview retrieved successfully.", 200));
+            }
+            catch (Exception ex)
+            {
+                // Capture complete context for diagnostics, but ensure no sensitive data is logged.
+                _logger.LogError(ex, "Error occurred while processing GetPurchaseInvoiceOverview. TenantId: {TenantId}, CorrelationId: {CorrelationId}",
+                    tenantId, correlationId);
+
+                // Do not expose internal details to clients. Return a generic 500 response.
+                return StatusCode(500, ApiResponse<object>.ErrorResponse("Internal Server Error", "An unexpected error occurred while processing the purchase invoice overview.", 500));
+            }
+        }
+
         /// <summary>
         /// Gets infrastructure projects for a tenant as a lightweight view model.
         /// </summary>