Enhance querying and performance in GymMgmt API

Introduced advanced filtering, sorting, and pagination for members
and subscriptions via new endpoints in `MembersController` and
`SubscriptionsController`. Added `DashboardController` for member
statistics. Implemented query handlers using Dapper for efficient
database operations. Introduced DTOs, enums, and `PaginatedList<T>`
for consistent data handling.

Added `ISqlConnectionFactory` for centralized SQL connection
management and enhanced logging. Optimized database performance
with indexes and explicit enum values. Updated `Program.cs` and
DI configuration to register new services. Removed unused query
classes and improved dynamic SQL handling for secure queries.

Updated project files to include new dependencies (`Dapper`,
`Microsoft.Data.SqlClient`) and enhanced maintainability with
better logging and resource management.

Author: HamzaZeroual2

GymMgmt.Api/Controllers/Dashboard/DashboardController.cs

@@ -0,0 +1,33 @@
+using GymMgmt.Api.Middlewares.Responses;
+using GymMgmt.Application.Features.Members.Queries.GetMemberStatistics;
+using GymMgmt.Application.Features.Members.Queries;
+using MediatR;
+using Microsoft.AspNetCore.Authorization;
+using Microsoft.AspNetCore.Http;
+using Microsoft.AspNetCore.Mvc;
+using System.Net;
+
+namespace GymMgmt.Api.Controllers.Dashboard
+{
+    [Route("api/[controller]")]
+    [ApiController]
+    public class DashboardController : ControllerBase
+    {
+        private readonly IMediator _mediator;
+
+        public DashboardController(IMediator mediator)
+        {
+            _mediator = mediator;
+        }
+
+        [AllowAnonymous]
+        [HttpGet("Stats")]
+        [ProducesResponseType(typeof(ApiResponse<MemberStatisticsDto>), (int)HttpStatusCode.OK)]
+        [ProducesResponseType(typeof(ApiResponse<object>), (int)HttpStatusCode.BadRequest)]
+        public async Task<ActionResult> GetStats()
+        {
+            var result = await _mediator.Send(new GetMemberStatisticsQuery());
+            return Ok(ApiResponse<MemberStatisticsDto>.Success(result));
+        }
+    }
+}

GymMgmt.Api/Controllers/MemberShipsPlans/MemberShipsPlansController.cs

@@ -1,5 +1,4 @@
 using GymMgmt.Api.Middlewares.Responses;
-using GymMgmt.Application.Common.Exceptions;
 using GymMgmt.Application.Features.Memberships.CreateMembership;
 using GymMgmt.Application.Features.Memberships.GetAllMemberShipsPlans;
 using GymMgmt.Application.Features.Memberships.GetMemberShipPlanById;
@@ -8,7 +7,6 @@
 using Microsoft.AspNetCore.Authorization;
 using Microsoft.AspNetCore.Mvc;
 using System.Net;
-using static Microsoft.EntityFrameworkCore.DbLoggerCategory.Database;
 
 namespace GymMgmt.Api.Controllers.MemberShipsPlans
 {

GymMgmt.Api/Controllers/Members/MembersController.cs

@@ -1,10 +1,16 @@
 using GymMgmt.Api.Middlewares.Responses;
+using GymMgmt.Application.Common.Models;
+using GymMgmt.Application.Features.Members;
 using GymMgmt.Application.Features.Members.CreateMember;
 using GymMgmt.Application.Features.Members.GetAllMembers;
 using GymMgmt.Application.Features.Members.GetMemberById;
 using GymMgmt.Application.Features.Members.PayInsurrance;
+using GymMgmt.Application.Features.Members.Queries.GetmembersByStatus;
+using GymMgmt.Application.Features.Members.Queries.GetMemberStatistics;
+using GymMgmt.Application.Features.Members.Queries;
 using GymMgmt.Application.Features.Members.UpdateMember;
 using GymMgmt.Application.Features.Memberships.UpdateMembershipPlan;
+using GymMgmt.Application.Features.Subscriptions.GetAllSubscriptions;
 using MediatR;
 using Microsoft.AspNetCore.Authorization;
 using Microsoft.AspNetCore.Mvc;
@@ -58,6 +64,21 @@ public async Task<ActionResult> GetAllMembers()
             var result = await _mediator.Send(new GetAllMembersQuery());
             return Ok(ApiResponse<IEnumerable<ReadMemberDto>>.Success(result));
         }
+       
+
+        [AllowAnonymous]
+        [HttpGet("Memberslist/{filter}")]
+        [ProducesResponseType(typeof(ApiResponse<PaginatedList<MemberListDto>>), (int)HttpStatusCode.OK)]
+        [ProducesResponseType(typeof(ApiResponse<object>), (int)HttpStatusCode.BadRequest)]
+        public async Task<ActionResult> GetList(
+            MemberStatusFilter filter,
+            [FromQuery] int pageNumber = 1,
+            [FromQuery] int pageSize = 10)
+        {
+            var result = await _mediator.Send(new GetMembersByStatusQuery(filter, pageNumber, pageSize));
+            
+            return Ok(ApiResponse<PaginatedList<MemberListDto>>.Success(result));
+        }
 
         [AllowAnonymous]
         [HttpPut("{id:Guid}")]
@@ -85,5 +106,6 @@ public async Task<ActionResult> PayInsurance([FromBody] CreateInsurancePaymentCo
             return Ok(ApiResponse<bool>.Success(result));
         }
 
+        
     }
 }

GymMgmt.Api/Controllers/Subscriptions/SubscriptionsController.cs

@@ -1,6 +1,8 @@
 using GymMgmt.Api.Middlewares.Responses;
+using GymMgmt.Application.Common.Models;
 using GymMgmt.Application.Features.Subscriptions.CancelSubscription;
 using GymMgmt.Application.Features.Subscriptions.ExtendSubscription;
+using GymMgmt.Application.Features.Subscriptions.GetAllSubscriptions;
 using GymMgmt.Application.Features.Subscriptions.StartSubscription;
 using MediatR;
 using Microsoft.AspNetCore.Authorization;
@@ -49,5 +51,20 @@ public async Task<ActionResult> CancelSubscription([FromBody] CancelSubscription
             var result = await _mediator.Send(command);
             return Ok(ApiResponse<bool>.Success(result, "Subscription cancelled successfully"));
         }
+        /// <summary>
+        /// Gets a paginated list of subscriptions with filtering and sorting.
+        /// </summary>
+        /// 
+        [AllowAnonymous]
+        [HttpGet("GetSubscriptions")]
+        [ProducesResponseType(typeof(ApiResponse<PaginatedList<SubscriptionDto>>), StatusCodes.Status200OK)]
+        public async Task<ActionResult<ApiResponse<PaginatedList<SubscriptionDto>>>> GetSubscriptions(
+            [FromQuery] GetSubscriptionsQuery query,
+            CancellationToken cancellationToken)
+        {
+            // MediatR sends the query to your GetSubscriptionsHandler
+            var result = await _mediator.Send(query, cancellationToken);
+            return Ok(ApiResponse<PaginatedList<SubscriptionDto>>.Success(result, "Subscription Retrieved successfully"));
+        }
     }
 }

GymMgmt.Api/Program.cs

@@ -8,6 +8,7 @@
 using Microsoft.AspNetCore.Authorization;
 using Microsoft.OpenApi.Models;
 using GymMgmt.Api.Middlewares;
+using System.Text.Json.Serialization;
 
 namespace GymMgmt.Api
 {
@@ -99,6 +100,12 @@ public static async Task Main(string[] args)
                     }
             });
             });
+            builder.Services.AddControllers()
+                .AddJsonOptions(options =>
+                {
+                    // This allows passing "Active" instead of 1 in JSON bodies and often helps query strings too
+                    options.JsonSerializerOptions.Converters.Add(new JsonStringEnumConverter());
+                });
 
 
             var app = builder.Build();

GymMgmt.Application/Common/Interfaces/ISqlConnectionFactory.cs

@@ -0,0 +1,12 @@
+using System.Data;
+
+
+namespace GymMgmt.Application.Common.Interfaces
+{
+    public interface ISqlConnectionFactory
+    {
+        IDbConnection GetOpenConnection();
+        IDbConnection CreateNewConnection();
+        string GetConnectionString();
+    }
+}

GymMgmt.Application/Features/Members/MemberStatusFilter.cs

@@ -0,0 +1,16 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace GymMgmt.Application.Features.Members
+{
+    public enum MemberStatusFilter
+    {
+        Active = 1,
+        GracePeriod = 2,
+        Expired = 3,
+        Cancelled = 4
+    }
+}

GymMgmt.Application/Features/Members/PayInsurrance/CreateInsurancePaymentCommandHandler.cs

@@ -3,11 +3,7 @@
 using GymMgmt.Domain.Entities.Members;
 using GymMgmt.Domain.Entities.Payments;
 using MediatR;
-using System;
-using System.Collections.Generic;
-using System.Linq;
-using System.Text;
-using System.Threading.Tasks;
+
 
 namespace GymMgmt.Application.Features.Members.PayInsurrance
 {

GymMgmt.Application/Features/Members/Queries/GetMemberStatistics/GetMemberStatisticsHandler.cs

@@ -0,0 +1,52 @@
+using Dapper;
+using GymMgmt.Application.Common.Interfaces;
+using MediatR;
+
+
+namespace GymMgmt.Application.Features.Members.Queries.GetMemberStatistics
+{
+    public class GetMemberStatisticsHandler : IRequestHandler<GetMemberStatisticsQuery, MemberStatisticsDto>
+    {
+        private readonly ISqlConnectionFactory _connectionFactory;
+
+        public GetMemberStatisticsHandler(ISqlConnectionFactory connectionFactory)
+        {
+            _connectionFactory = connectionFactory;
+        }
+
+        public async Task<MemberStatisticsDto> Handle(GetMemberStatisticsQuery request, CancellationToken cancellationToken)
+        {
+            using var connection = _connectionFactory.CreateNewConnection();
+
+            // We fetch the GracePeriod days from settings dynamically
+            // Then we use CASE WHEN to categorize every subscription efficiently
+            var sql = @"
+            DECLARE @GraceDays INT = (SELECT TOP 1 SubscriptionGracePeriodInDays FROM ClubSettings);
+            DECLARE @Now DATETIME2 = SYSDATETIME();
+
+            SELECT 
+                COUNT(CASE 
+                    WHEN s.Status = 'Active' AND s.EndDate >= @Now 
+                    THEN 1 END) as ActiveCount,
+
+                COUNT(CASE 
+                    WHEN s.Status = 'Active' AND s.EndDate < @Now AND s.EndDate >= DATEADD(day, -@GraceDays, @Now) 
+                    THEN 1 END) as GracePeriodCount,
+
+                COUNT(CASE 
+                    WHEN (s.Status = 'Active' AND s.EndDate < DATEADD(day, -@GraceDays, @Now)) OR s.Status = 'Expired'
+                    THEN 1 END) as ExpiredCount,
+
+                COUNT(CASE 
+                    WHEN s.Status = 'Cancelled' 
+                    THEN 1 END) as CancelledCount
+
+            FROM Subscriptions s
+            -- Ensure we only count the latest/relevant subscription per member if needed
+            -- For now, this counts ALL subscriptions in the system
+            WHERE s.WillNotRenew = 0 OR s.Status = 'Cancelled'";
+
+            return await connection.QuerySingleAsync<MemberStatisticsDto>(sql);
+        }
+    }
+}

GymMgmt.Application/Features/Members/Queries/GetMemberStatistics/GetMemberStatisticsQuery.cs

@@ -0,0 +1,11 @@
+using MediatR;
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace GymMgmt.Application.Features.Members.Queries.GetMemberStatistics
+{
+    public record GetMemberStatisticsQuery : IRequest<MemberStatisticsDto>;
+}