APIs Repository - Code Quality Report¶

Project: Psyter REST API Backend
Analysis Date: November 7, 2025
Total Lines of Code: ~42,000
Technology Stack: ASP.NET Web API 2, .NET Framework 4.7.2, C#

Executive Summary¶

This report analyzes code quality, technical debt, maintainability, and refactoring opportunities in the Psyter APIs repository. The assessment covers code organization, design patterns, complexity metrics, code smells, and best practice violations.

Overall Code Quality Score: C+ (68/100)¶

Category	Score	Grade	Status
Architecture & Design	72/100	C+	🟡 Fair
Code Organization	65/100	D+	🟠 Needs Work
Maintainability	58/100	D	🟠 Needs Work
Testability	35/100	F	🔴 Poor
Documentation	45/100	F	🔴 Poor
Best Practices	70/100	C	🟡 Fair
Error Handling	75/100	C+	🟡 Fair
Performance	62/100	D+	🟠 Needs Work

Key Findings Summary¶

Strengths:
- ✅ Consistent repository pattern usage
- ✅ Centralized exception handling
- ✅ Separation of concerns (Controllers/Repositories/Helpers)
- ✅ OAuth 2.0 implementation
- ✅ Anti-XSS filter implementation

Critical Issues:
- ❌ Empty BaseRepository - Core pattern not implemented
- ❌ No unit tests - Zero test coverage
- ❌ High cyclomatic complexity - Methods with 20+ decision points
- ❌ Massive God classes - 2000+ line files
- ❌ No dependency injection - Tight coupling
- ❌ Duplicate code - High redundancy across repositories

Architecture & Design Patterns¶

Score: 72/100 (C+)¶

Design Patterns Identified¶

✅ Repository Pattern (Partial Implementation)¶

Good:

public class UserRepository : BaseRepository
{
    public User GetUser(int userId)
    {
        using (SqlConnection connection = GetConnection())
        {
            using (SqlCommand command = new SqlCommand())
            {
                command.Connection = connection;
                command.CommandText = "User_GetById";
                command.CommandType = CommandType.StoredProcedure;
                command.Parameters.AddWithValue("@UserId", userId);

                connection.Open();
                using (SqlDataReader reader = command.ExecuteReader())
                {
                    if (reader.Read())
                    {
                        return MapUser(reader);
                    }
                }
            }
        }
        return null;
    }
}

Problems:
1. Empty BaseRepository - No shared functionality
2. No interfaces - Tight coupling, untestable
3. No Unit of Work - Transaction management scattered
4. Direct ADO.NET - Verbose, repetitive code

BaseRepository.cs (CRITICAL ISSUE):

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;

namespace PsyterAPI.Repositories
{
    public class BaseRepository
    {
        // ❌ EMPTY CLASS - Repository pattern not utilized
    }
}

Impact:
- Code Duplication: Every repository reimplements connection handling
- Inconsistency: No standardized approach to database access
- Missed Opportunity: No centralized logging, error handling, transaction management

Recommended Fix:

public abstract class BaseRepository : IDisposable
{
    protected readonly string _connectionString;
    protected SqlConnection _connection;
    protected SqlTransaction _transaction;

    protected BaseRepository()
    {
        _connectionString = ConfigurationManager.ConnectionStrings["PsyterDatabase"].ConnectionString;
    }

    protected SqlConnection GetConnection()
    {
        if (_connection == null)
        {
            _connection = new SqlConnection(_connectionString);
        }

        if (_connection.State != ConnectionState.Open)
        {
            _connection.Open();
        }

        return _connection;
    }

    protected T ExecuteStoredProcedure<T>(string procedureName, 
                                         Dictionary<string, object> parameters,
                                         Func<SqlDataReader, T> mapper)
    {
        try
        {
            using (var command = new SqlCommand(procedureName, GetConnection()))
            {
                command.CommandType = CommandType.StoredProcedure;

                if (parameters != null)
                {
                    foreach (var param in parameters)
                    {
                        command.Parameters.AddWithValue(param.Key, param.Value ?? DBNull.Value);
                    }
                }

                using (var reader = command.ExecuteReader())
                {
                    if (reader.Read())
                    {
                        return mapper(reader);
                    }
                }
            }

            return default(T);
        }
        catch (SqlException ex)
        {
            ExceptionManager.LogException(ex, procedureName);
            throw;
        }
    }

    protected List<T> ExecuteStoredProcedureList<T>(string procedureName,
                                                   Dictionary<string, object> parameters,
                                                   Func<SqlDataReader, T> mapper)
    {
        var results = new List<T>();

        try
        {
            using (var command = new SqlCommand(procedureName, GetConnection()))
            {
                command.CommandType = CommandType.StoredProcedure;

                if (parameters != null)
                {
                    foreach (var param in parameters)
                    {
                        command.Parameters.AddWithValue(param.Key, param.Value ?? DBNull.Value);
                    }
                }

                using (var reader = command.ExecuteReader())
                {
                    while (reader.Read())
                    {
                        results.Add(mapper(reader));
                    }
                }
            }

            return results;
        }
        catch (SqlException ex)
        {
            ExceptionManager.LogException(ex, procedureName);
            throw;
        }
    }

    public void BeginTransaction()
    {
        _transaction = GetConnection().BeginTransaction();
    }

    public void CommitTransaction()
    {
        _transaction?.Commit();
        _transaction?.Dispose();
        _transaction = null;
    }

    public void RollbackTransaction()
    {
        _transaction?.Rollback();
        _transaction?.Dispose();
        _transaction = null;
    }

    public void Dispose()
    {
        _transaction?.Dispose();
        _connection?.Dispose();
    }
}

// Usage in UserRepository:
public class UserRepository : BaseRepository
{
    public User GetUser(int userId)
    {
        var parameters = new Dictionary<string, object>
        {
            { "@UserId", userId }
        };

        return ExecuteStoredProcedure("User_GetById", parameters, MapUser);
    }

    private User MapUser(SqlDataReader reader)
    {
        return new User
        {
            UserId = reader.GetInt32("UserId"),
            FirstName = reader.GetString("FirstName"),
            LastName = reader.GetString("LastName"),
            Email = reader.GetString("Email")
            // ... other mappings
        };
    }
}

Priority: P1 (High)
Impact: Reduces ~5,000 lines of duplicate code

❌ No Dependency Injection¶

Current Problem:

public class UserController : ApiController
{
    UserRepository userRepository = new UserRepository(); // ❌ Tight coupling
    NotificationRepository notificationRepository = new NotificationRepository(); // ❌ Not testable

    [Route("GetUser")]
    public IHttpActionResult GetUser(int userId)
    {
        var user = userRepository.GetUser(userId);
        return Ok(user);
    }
}

Issues:
- Tight Coupling: Cannot swap implementations
- Untestable: Cannot mock repositories for unit tests
- No Lifecycle Management: New instance per method call (potential)
- Violates SOLID: Depends on concrete implementations

Recommended Implementation:

Step 1: Define Interfaces

public interface IUserRepository
{
    User GetUser(int userId);
    User GetUserByEmail(string email);
    int CreateUser(User user);
    bool UpdateUser(User user);
    bool DeleteUser(int userId);
}

public class UserRepository : BaseRepository, IUserRepository
{
    // Existing implementation
}

Step 2: Setup Dependency Injection (Unity Container)

// Install-Package Unity.WebAPI

public static class UnityConfig
{
    public static void RegisterComponents()
    {
        var container = new UnityContainer();

        // Register repositories
        container.RegisterType<IUserRepository, UserRepository>(new PerRequestLifetimeManager());
        container.RegisterType<IAppointmentRepository, AppointmentRepository>(new PerRequestLifetimeManager());
        container.RegisterType<IPaymentRepository, PaymentRepository>(new PerRequestLifetimeManager());
        // ... register all repositories

        // Register services
        container.RegisterType<INotificationService, NotificationService>(new PerRequestLifetimeManager());
        container.RegisterType<IVideoSDKService, VideoSDKService>(new PerRequestLifetimeManager());

        GlobalConfiguration.Configuration.DependencyResolver = new UnityDependencyResolver(container);
    }
}

// Global.asax.cs
protected void Application_Start()
{
    UnityConfig.RegisterComponents();
    // ... other startup code
}

Step 3: Update Controllers

public class UserController : ApiController
{
    private readonly IUserRepository _userRepository;
    private readonly INotificationService _notificationService;

    // Constructor injection
    public UserController(IUserRepository userRepository, 
                         INotificationService notificationService)
    {
        _userRepository = userRepository ?? throw new ArgumentNullException(nameof(userRepository));
        _notificationService = notificationService ?? throw new ArgumentNullException(nameof(notificationService));
    }

    [Route("GetUser")]
    public IHttpActionResult GetUser(int userId)
    {
        var user = _userRepository.GetUser(userId);

        if (user == null)
        {
            return NotFound();
        }

        return Ok(new BaseResponse
        {
            Status = 1,
            Message = "Success",
            Data = user
        });
    }
}

Benefits:
- ✅ Testable with mocks
- ✅ Loosely coupled
- ✅ Lifecycle management
- ✅ Easy to swap implementations
- ✅ Follows SOLID principles

Priority: P1 (High)
Timeline: 3-4 weeks

❌ CQ-NEW-01: Exception Handling Anti-Patterns¶

Severity: HIGH
Impact: Production Crashes, Data Loss, Hidden Bugs

Issues Identified:

1. Catching Generic Exceptions

// ❌ BAD - Too broad
try
{
    userRepository.UpdateUser(user);
}
catch (Exception ex)
{
    // Catches even critical system exceptions (OutOfMemoryException, StackOverflowException)
    LogError(ex);
    return false;
}

2. Empty Catch Blocks

// ❌ CRITICAL - Silent failures
try
{
    paymentRepository.ProcessPayment(payment);
}
catch
{
    // Error swallowed - user thinks payment succeeded
}

3. Losing Stack Traces

// ❌ WRONG - Loses original stack trace
catch (Exception ex)
{
    LogError(ex);
    throw ex; // Should be just "throw;"
}

Recommended Patterns:

// ✅ CORRECT: Specific exception handling
public async Task<PaymentResult> ProcessPaymentAsync(Payment payment)
{
    try
    {
        var result = await _paymentGateway.ChargeAsync(payment);
        _logger.Info("Payment processed: {PaymentId}", payment.Id);
        return result;
    }
    catch (PaymentGatewayException ex) when (ex.Reason == "InsufficientFunds")
    {
        // Expected business exception
        _logger.Warning("Insufficient funds: {PaymentId}", payment.Id);
        return PaymentResult.Failed("Insufficient funds");
    }
    catch (SqlException ex) when (ex.Number == -2) // Timeout
    {
        _logger.Error(ex, "Database timeout: {PaymentId}", payment.Id);
        throw new TransientException("Database unavailable", ex);
    }
    catch (Exception ex)
    {
        // Truly unexpected - log and rethrow
        _logger.Fatal(ex, "Unexpected error: {PaymentId}", payment.Id);
        throw; // Preserve stack trace
    }
}

// Global exception filter
public class GlobalExceptionFilter : ExceptionFilterAttribute
{
    public override void OnException(HttpActionExecutedContext context)
    {
        _logger.Error(context.Exception, "Unhandled exception");

        context.Response = context.Exception switch
        {
            ArgumentException _ => CreateResponse(HttpStatusCode.BadRequest, "Invalid parameters"),
            UnauthorizedAccessException _ => CreateResponse(HttpStatusCode.Unauthorized, "Unauthorized"),
            NotFoundException _ => CreateResponse(HttpStatusCode.NotFound, "Not found"),
            _ => CreateResponse(HttpStatusCode.InternalServerError, "Internal error")
        };
    }
}

Priority: P1 (High)
Timeline: 2-3 weeks

❌ CQ-NEW-02: IDisposable Not Implemented¶

Severity: HIGH
Impact: Memory Leaks, Connection Exhaustion

Issues:

1. DbContext Not Disposed

// ❌ LEAK - DbContext never disposed
public class UserRepository
{
    private PsyterDatabaseEntities db = new PsyterDatabaseEntities();

    public User GetUser(int id)
    {
        return db.Users.Find(id); // Connection held indefinitely
    }
}

Impact:
- SQL connection pool exhaustion (100 max)
- Memory leaks (EF change tracker grows)
- After ~100 requests: “Timeout expired…”

2. HttpClient Per Request

// ❌ SOCKET EXHAUSTION
using (var client = new HttpClient())
{
    var response = await client.GetAsync(url);
    // Creates new socket every time
    // Sockets in TIME_WAIT for 240 seconds
}

Impact:
- After 1,000 requests in 4 min: “Cannot assign requested address”

Correct Patterns:

// ✅ DbContext per request with DI
public class UserRepository : IUserRepository, IDisposable
{
    private readonly PsyterDatabaseEntities _db;

    public UserRepository(PsyterDatabaseEntities db)
    {
        _db = db;
    }

    public void Dispose()
    {
        _db?.Dispose();
    }
}

// Register as scoped (per HTTP request)
container.RegisterType<PsyterDatabaseEntities>(new PerRequestLifetimeManager());

// ✅ HttpClient singleton
public class VideoSDKService
{
    private static readonly HttpClient _httpClient = new HttpClient();

    public async Task<string> GetTokenAsync()
    {
        return await _httpClient.GetStringAsync(url);
    }
}

Priority: P0 (Critical - blocks scalability)
Timeline: 2-3 weeks

❌ CQ-NEW-03: DateTime UTC/Local Confusion¶

Severity: MEDIUM
Impact: Time Zone Bugs, Scheduling Errors

Issue:

// ❌ WRONG - Server local time
var now = DateTime.Now; // PST, EST, UTC?
appointment.ScheduledTime = now;

// If server in PST, appointment saved as "2024-01-15 14:00:00"
// If server moves to UTC → same time interpreted differently!

Impact:
- Appointments scheduled for wrong time
- Reports show incorrect dates
- HIPAA audit trail corrupted

Correct Pattern:

// ✅ ALWAYS store UTC
var now = DateTime.UtcNow;
appointment.ScheduledTimeUtc = now;

// Convert to user time zone for display only
public DateTime ToUserTime(DateTime utc, string timeZoneId)
{
    var tz = TimeZoneInfo.FindSystemTimeZoneById(timeZoneId);
    return TimeZoneInfo.ConvertTimeFromUtc(utc, tz);
}

// In response
return new
{
    ScheduledTimeUtc = appointment.ScheduledTimeUtc,
    ScheduledTimeLocal = ToUserTime(appointment.ScheduledTimeUtc, user.TimeZoneId)
};

Priority: P1 (Critical for scheduling)
Timeline: 2 weeks + database migration

❌ CQ-NEW-04: Inefficient String Concatenation¶

Severity: MEDIUM
Impact: Performance Degradation, GC Pressure

Issue:

// ❌ BAD - Creates multiple string objects
string query = "SELECT * FROM Users WHERE ";
query += "Status = 'Active' ";
foreach (var role in roles)
{
    query += "'" + role + "',"; // New string each iteration!
}

// 100 roles = 103+ string objects in memory

Performance:

100 roles   → 103 allocations (~41KB)
1000 roles  → 1003 allocations (~4.1MB)

At 1000 req/sec = 4.1 GB/sec allocation!

Correct Pattern:

// ✅ GOOD - Single allocation
var query = new StringBuilder();
query.Append("SELECT * FROM Users WHERE Status = 'Active' AND Role IN (");

for (int i = 0; i < roles.Count; i++)
{
    query.Append("'").Append(roles[i]).Append("'");
    if (i < roles.Count - 1) query.Append(",");
}

query.Append(")");
var finalQuery = query.ToString();

Rule: 4+ concatenations or loops → use StringBuilder

Priority: P2 (Medium)
Timeline: 1 week

❌ CQ-NEW-05: Inefficient LINQ Queries¶

Severity: MEDIUM
Impact: N+1 Queries, Performance

Issue:

// ❌ N+1 Problem
var users = db.Users.ToList(); // Query 1

foreach (var user in users)
{
    var appointments = db.Appointments
        .Where(a => a.UserId == user.UserId)
        .ToList(); // Query 2, 3, 4...
}

// 100 users = 101 queries!

Correct Patterns:

// ✅ Eager loading
var users = db.Users
    .Include(u => u.Appointments)
    .ToList(); // Single JOIN query

// ✅ Projection
var users = db.Users
    .Select(u => new
    {
        User = u,
        AppointmentCount = u.Appointments.Count() // COUNT in SQL
    })
    .ToList();

// ❌ Load all then filter
var active = db.Users.ToList() // Loads ALL
    .Where(u => u.Status == "Active"); // Filters in memory

// ✅ Filter in database
var active = db.Users
    .Where(u => u.Status == "Active") // SQL WHERE
    .ToList();

Priority: P1 (High - significant impact)
Timeline: 2-3 weeks

❌ CQ-NEW-06: Configuration Hardcoded in Code¶

Severity: MEDIUM
Impact: Deployment Complexity, Security

Issue:

// ❌ Hardcoded
public class VideoSDKService
{
    private const string ApiUrl = "https://api.videosdk.live/v2/rooms";
    private const string ApiKey = "abcd1234..."; // Secret in code!
}

Correct Pattern:

// ✅ Configuration class
public class VideoSDKConfig
{
    public string ApiUrl { get; set; }
    public string ApiKey { get; set; }
    public int TokenExpiry { get; set; }
}

public class VideoSDKService
{
    private readonly VideoSDKConfig _config;

    public VideoSDKService()
    {
        _config = new VideoSDKConfig
        {
            ApiUrl = ConfigurationManager.AppSettings["VideoSDK:ApiUrl"],
            ApiKey = ConfigurationManager.AppSettings["VideoSDK:ApiKey"],
            TokenExpiry = int.Parse(ConfigurationManager.AppSettings["VideoSDK:TokenExpiry"] ?? "3600")
        };
    }
}

// Web.config
<appSettings>
  <add key="VideoSDK:ApiUrl" value="https://api.videosdk.live/v2/rooms"/>
  <add key="VideoSDK:ApiKey" value="#{VideoSDK_ApiKey}#"/> <!-- From Azure Key Vault -->
  <add key="VideoSDK:TokenExpiry" value="3600"/>
</appSettings>

Priority: P2 (Medium)
Timeline: 1-2 weeks

❌ CQ-NEW-07: Dead Code and Commented Code¶

Severity: LOW
Impact: Maintainability, Confusion

Issue:

// ❌ Large commented blocks
public void ProcessPayment(Payment payment)
{
    // Old implementation - 50 lines commented
    // var gateway = new OldGateway();
    // var result = gateway.Process();
    // ...

    var gateway = new SmartRoutingGateway();
    return gateway.Process(payment);
}

Solution:

// ✅ Delete - use git history
public void ProcessPayment(Payment payment)
{
    var gateway = new SmartRoutingGateway();
    return gateway.Process(payment);
}

Action: Audit for TODO, HACK, FIXME, commented code blocks

Priority: P3 (Low - cleanup)
Timeline: 2-3 days

❌ No Service Layer¶

Current Architecture:

Controller → Repository → Database

Problem: Business logic scattered across controllers

Example:

[Route("BookAppointment")]
public IHttpActionResult BookAppointment(AppointmentRequest request)
{
    // ❌ Business logic in controller
    var provider = providerRepository.GetProvider(request.ProviderId);
    if (provider == null)
        return BadRequest("Provider not found");

    var client = userRepository.GetUser(request.ClientId);
    if (client == null)
        return BadRequest("Client not found");

    // Check availability
    var existingAppointments = appointmentRepository.GetProviderAppointments(
        request.ProviderId, request.Date);

    if (existingAppointments.Any(a => a.StartTime == request.StartTime))
        return BadRequest("Time slot not available");

    // Create appointment
    var appointment = new Appointment
    {
        ProviderId = request.ProviderId,
        ClientId = request.ClientId,
        StartTime = request.StartTime,
        // ... mapping
    };

    int appointmentId = appointmentRepository.CreateAppointment(appointment);

    // Send notifications
    notificationRepository.SendNotification(provider.UserId, "New appointment booked");
    notificationRepository.SendNotification(client.UserId, "Appointment confirmed");

    return Ok(new { AppointmentId = appointmentId });
}

Issues:
- Fat Controllers: Business logic in presentation layer
- Code Duplication: Same validation logic repeated
- Hard to Test: Cannot test business logic independently
- No Reusability: Cannot call from other places

Recommended Architecture:

Controller → Service → Repository → Database

Implementation:

public interface IAppointmentService
{
    AppointmentResult BookAppointment(BookAppointmentRequest request);
    AppointmentResult CancelAppointment(int appointmentId, int userId);
    List<Appointment> GetUserAppointments(int userId);
}

public class AppointmentService : IAppointmentService
{
    private readonly IAppointmentRepository _appointmentRepository;
    private readonly IUserRepository _userRepository;
    private readonly IProviderRepository _providerRepository;
    private readonly INotificationService _notificationService;

    public AppointmentService(
        IAppointmentRepository appointmentRepository,
        IUserRepository userRepository,
        IProviderRepository providerRepository,
        INotificationService notificationService)
    {
        _appointmentRepository = appointmentRepository;
        _userRepository = userRepository;
        _providerRepository = providerRepository;
        _notificationService = notificationService;
    }

    public AppointmentResult BookAppointment(BookAppointmentRequest request)
    {
        // Validate provider exists
        var provider = _providerRepository.GetProvider(request.ProviderId);
        if (provider == null)
        {
            return AppointmentResult.Error("Provider not found");
        }

        // Validate client exists
        var client = _userRepository.GetUser(request.ClientId);
        if (client == null)
        {
            return AppointmentResult.Error("Client not found");
        }

        // Check availability
        if (!IsTimeSlotAvailable(request.ProviderId, request.Date, request.StartTime))
        {
            return AppointmentResult.Error("Time slot not available");
        }

        // Create appointment
        var appointment = MapRequestToAppointment(request);
        int appointmentId = _appointmentRepository.CreateAppointment(appointment);

        // Send notifications asynchronously
        Task.Run(() =>
        {
            _notificationService.SendAppointmentConfirmation(provider.UserId, appointmentId);
            _notificationService.SendAppointmentConfirmation(client.UserId, appointmentId);
        });

        return AppointmentResult.Success(appointmentId);
    }

    private bool IsTimeSlotAvailable(int providerId, DateTime date, TimeSpan startTime)
    {
        var existingAppointments = _appointmentRepository.GetProviderAppointments(providerId, date);
        return !existingAppointments.Any(a => a.StartTime == startTime);
    }

    private Appointment MapRequestToAppointment(BookAppointmentRequest request)
    {
        return new Appointment
        {
            ProviderId = request.ProviderId,
            ClientId = request.ClientId,
            StartTime = request.StartTime,
            EndTime = request.EndTime,
            // ... other mappings
        };
    }
}

// Slim controller
public class AppointmentController : ApiController
{
    private readonly IAppointmentService _appointmentService;

    public AppointmentController(IAppointmentService appointmentService)
    {
        _appointmentService = appointmentService;
    }

    [Route("BookAppointment")]
    [HttpPost]
    public IHttpActionResult BookAppointment(BookAppointmentRequest request)
    {
        if (!ModelState.IsValid)
        {
            return BadRequest(ModelState);
        }

        var result = _appointmentService.BookAppointment(request);

        if (!result.Success)
        {
            return BadRequest(result.ErrorMessage);
        }

        return Ok(new BaseResponse
        {
            Status = 1,
            Message = "Appointment booked successfully",
            Data = new { AppointmentId = result.AppointmentId }
        });
    }
}

Benefits:
- ✅ Thin controllers (presentation only)
- ✅ Reusable business logic
- ✅ Testable services
- ✅ Single Responsibility Principle
- ✅ Consistent business rules

Priority: P2 (Medium - long-term improvement)
Timeline: 2-3 months

Code Organization¶

Score: 65/100 (D+)¶

Directory Structure Analysis¶

Current Structure:

PsyterAPI/
├── Controllers/           (18 files) ✅ Good
├── Repositories/          (23 files) ✅ Good
├── Common/               (22 files) ⚠️ Mixed responsibilities
├── Models/               (60+ files) ⚠️ Flat structure
├── App_Start/            ✅ Standard
└── Properties/           ✅ Standard

Issues Identified¶

1. Flat Models Directory¶

Current:

Models/
├── User.cs
├── UserAuthRequest.cs
├── UserRegistrationRequest.cs
├── UserProfileResponse.cs
├── Appointment.cs
├── AppointmentRequest.cs
├── AppointmentResponse.cs
├── Payment.cs
├── PaymentRequest.cs
... (60+ files in one directory)

Problem: Hard to navigate, no logical grouping

Recommended:

Models/
├── Entities/              # Database entities
│   ├── User.cs
│   ├── Appointment.cs
│   ├── Payment.cs
├── Requests/              # API request DTOs
│   ├── UserRequests/
│   │   ├── UserAuthRequest.cs
│   │   ├── UserRegistrationRequest.cs
│   │   ├── UpdateUserProfileRequest.cs
│   ├── AppointmentRequests/
│   │   ├── BookAppointmentRequest.cs
│   │   ├── CancelAppointmentRequest.cs
├── Responses/             # API response DTOs
│   ├── UserResponses/
│   │   ├── UserProfileResponse.cs
│   │   ├── UserListResponse.cs
│   ├── AppointmentResponses/
│   │   ├── AppointmentDetailsResponse.cs
├── Common/
│   ├── BaseResponse.cs
│   ├── PaginationRequest.cs
│   ├── PaginationResponse.cs

Priority: P2 (Medium)

2. Common Directory Mixed Concerns¶

Current Common/ Contains:
- SecurityHelper.cs - Security utilities ✅
- ExceptionManager.cs - Error handling ✅
- ConfigurationManager.cs - Configuration ✅
- VideoSDKManager.cs - Third-party integration ❌ Should be in Services/
- FirebaseManager.cs - Third-party integration ❌ Should be in Services/
- SmartRoutingHelper.cs - Payment gateway ❌ Should be in Services/Payment/
- PDFHelper.cs - Document generation ❌ Should be in Services/Documents/
- EmailHelper.cs - Email sending ❌ Should be in Services/Notifications/

Recommended Structure:

Common/
├── Helpers/
│   ├── SecurityHelper.cs
│   ├── DateTimeHelper.cs
│   ├── StringHelper.cs
├── Extensions/
│   ├── StringExtensions.cs
│   ├── DateTimeExtensions.cs
│   ├── EnumerableExtensions.cs
├── Utilities/
│   ├── ExceptionManager.cs
│   ├── LogManager.cs
│   ├── ConfigurationManager.cs

Services/
├── Notifications/
│   ├── IEmailService.cs
│   ├── EmailService.cs
│   ├── INotificationService.cs
│   ├── NotificationService.cs
│   ├── Firebase/
│   │   ├── IFirebaseService.cs
│   │   ├── FirebaseService.cs
├── Video/
│   ├── IVideoService.cs
│   ├── VideoSDKService.cs
├── Payment/
│   ├── IPaymentGateway.cs
│   ├── SmartRoutingPaymentGateway.cs
├── Documents/
│   ├── IPDFGenerator.cs
│   ├── PDFGenerator.cs

Priority: P2 (Medium)

Debt Items by Priority¶

🔴 P0 (Critical - Address Immediately)¶

1. Security Technical Debt
- MD5 password hashing → PBKDF2 migration
- Hardcoded secrets → Azure Key Vault
- Custom errors disabled → Proper error pages
- Risk if Ignored: Data breach, compliance violations

🟠 P1 (High - Address Soon)¶

2. No Unit Tests

// Current state: ZERO test coverage
// Tests/
//   (empty)

// Impact:
// - Cannot safely refactor
// - Regressions go undetected
// - Deployment confidence is low
// - Onboarding new developers is risky

Recommended Test Structure:

Tests/
├── PsyterAPI.UnitTests/
│   ├── Controllers/
│   │   ├── UserControllerTests.cs
│   │   ├── AppointmentControllerTests.cs
│   ├── Services/
│   │   ├── AppointmentServiceTests.cs
│   │   ├── NotificationServiceTests.cs
│   ├── Repositories/
│   │   ├── UserRepositoryTests.cs (integration tests)
│   ├── Helpers/
│   │   ├── SecurityHelperTests.cs
├── PsyterAPI.IntegrationTests/
│   ├── API/
│   │   ├── UserEndpointTests.cs
│   │   ├── AppointmentEndpointTests.cs
│   ├── Database/
│   │   ├── UserRepositoryIntegrationTests.cs

Sample Unit Test:

using NUnit.Framework;
using Moq;

[TestFixture]
public class AppointmentServiceTests
{
    private Mock<IAppointmentRepository> _appointmentRepository;
    private Mock<INotificationService> _notificationService;
    private AppointmentService _appointmentService;

    [SetUp]
    public void Setup()
    {
        _appointmentRepository = new Mock<IAppointmentRepository>();
        _notificationService = new Mock<INotificationService>();
        _appointmentService = new AppointmentService(
            _appointmentRepository.Object,
            _notificationService.Object);
    }

    [Test]
    public void BookAppointment_ValidRequest_ReturnsSuccess()
    {
        // Arrange
        var request = new BookAppointmentRequest
        {
            ProviderId = 1,
            ClientId = 2,
            Date = DateTime.Today.AddDays(1),
            StartTime = new TimeSpan(10, 0, 0)
        };

        _appointmentRepository
            .Setup(r => r.GetProviderAppointments(1, It.IsAny<DateTime>()))
            .Returns(new List<Appointment>());

        _appointmentRepository
            .Setup(r => r.CreateAppointment(It.IsAny<Appointment>()))
            .Returns(123);

        // Act
        var result = _appointmentService.BookAppointment(request);

        // Assert
        Assert.IsTrue(result.Success);
        Assert.AreEqual(123, result.AppointmentId);
        _notificationService.Verify(n => n.SendAppointmentConfirmation(It.IsAny<int>(), 123), Times.Exactly(2));
    }

    [Test]
    public void BookAppointment_TimeSlotTaken_ReturnsError()
    {
        // Arrange
        var request = new BookAppointmentRequest
        {
            ProviderId = 1,
            ClientId = 2,
            Date = DateTime.Today.AddDays(1),
            StartTime = new TimeSpan(10, 0, 0)
        };

        var existingAppointment = new Appointment
        {
            StartTime = new TimeSpan(10, 0, 0)
        };

        _appointmentRepository
            .Setup(r => r.GetProviderAppointments(1, It.IsAny<DateTime>()))
            .Returns(new List<Appointment> { existingAppointment });

        // Act
        var result = _appointmentService.BookAppointment(request);

        // Assert
        Assert.IsFalse(result.Success);
        Assert.AreEqual("Time slot not available", result.ErrorMessage);
        _appointmentRepository.Verify(r => r.CreateAppointment(It.IsAny<Appointment>()), Times.Never);
    }
}

Coverage Goals:
- Controllers: 80%+ (mostly integration tests)
- Services: 90%+ (business logic critical)
- Repositories: 70%+ (integration tests with database)
- Helpers: 95%+ (pure functions, easily testable)

Priority: P1 (High)
Timeline: 3-4 months (parallel with feature work)

3. Empty BaseRepository Pattern

Current Impact:
- 23 repository files each have duplicate code:
- Connection string retrieval (23x duplicated)
- Connection creation (23x duplicated)
- SqlCommand setup (23x duplicated)
- Error handling (23x duplicated)
- Disposal patterns (23x duplicated)

Lines of Duplicated Code: ~5,000 lines

Example Duplication:

// UserRepository.cs (lines 1-50)
private SqlConnection GetConnection()
{
    string connectionString = ConfigurationManager.ConnectionStrings["PsyterDatabase"].ConnectionString;
    return new SqlConnection(connectionString);
}

// AppointmentRepository.cs (lines 1-50)
private SqlConnection GetConnection()
{
    string connectionString = ConfigurationManager.ConnectionStrings["PsyterDatabase"].ConnectionString;
    return new SqlConnection(connectionString);
}

// PaymentRepository.cs (lines 1-50)
private SqlConnection GetConnection()
{
    string connectionString = ConfigurationManager.ConnectionStrings["PsyterDatabase"].ConnectionString;
    return new SqlConnection(connectionString);
}

// ... repeated 20 more times

Refactoring to BaseRepository saves:
- ~4,500 lines of code removed
- Centralized error handling
- Consistent transaction management
- Easier to add logging/monitoring

Priority: P1 (High)
ROI: Very high (reduces future maintenance significantly)

4. No Dependency Injection

Current Problems:

Problem 1: Tight Coupling

public class AppointmentController : ApiController
{
    // ❌ Cannot swap implementations
    AppointmentRepository appointmentRepository = new AppointmentRepository();
    UserRepository userRepository = new UserRepository();
    PaymentRepository paymentRepository = new PaymentRepository();

    // ❌ If constructor changes, breaks all usage
    // ❌ Cannot inject mock for testing
}

Problem 2: Lifecycle Issues

[Route("GetAppointments")]
public IHttpActionResult GetAppointments()
{
    // New instance created - is this intended?
    AppointmentRepository repo = new AppointmentRepository();
    var appointments = repo.GetAppointments();
    return Ok(appointments);
    // Repository not disposed - potential leak?
}

Problem 3: Cannot Unit Test

// IMPOSSIBLE to unit test this controller
// Cannot mock AppointmentRepository
// Must use real database = integration test only

[Test]
public void GetAppointments_ReturnsAppointments()
{
    var controller = new AppointmentController();
    // ❌ Will try to connect to real database
    // ❌ Cannot inject mock
    var result = controller.GetAppointments();
}

Priority: P1 (High)
Timeline: 3-4 weeks

🟡 P2 (Medium - Plan for Future)¶

5. Massive Code Duplication

Analysis Results:

Duplication Category 1: Repository CRUD Patterns

// Repeated in 23 repositories

// Pattern 1: Get by ID (duplicated 23x)
public Entity GetEntity(int id)
{
    using (SqlConnection connection = GetConnection())
    {
        using (SqlCommand command = new SqlCommand())
        {
            command.Connection = connection;
            command.CommandText = "Entity_GetById";
            command.CommandType = CommandType.StoredProcedure;
            command.Parameters.AddWithValue("@Id", id);

            connection.Open();
            using (SqlDataReader reader = command.ExecuteReader())
            {
                if (reader.Read())
                {
                    return MapEntity(reader);
                }
            }
        }
    }
    return null;
}

// Pattern 2: Get all (duplicated 23x)
public List<Entity> GetAllEntities()
{
    List<Entity> entities = new List<Entity>();
    using (SqlConnection connection = GetConnection())
    {
        using (SqlCommand command = new SqlCommand())
        {
            command.Connection = connection;
            command.CommandText = "Entity_GetAll";
            command.CommandType = CommandType.StoredProcedure;

            connection.Open();
            using (SqlDataReader reader = command.ExecuteReader())
            {
                while (reader.Read())
                {
                    entities.Add(MapEntity(reader));
                }
            }
        }
    }
    return entities;
}

Duplication Category 2: DataReader Mapping

// Repeated pattern in every repository

private Entity MapEntity(SqlDataReader reader)
{
    return new Entity
    {
        Id = reader.IsDBNull(0) ? 0 : reader.GetInt32(0),
        Name = reader.IsDBNull(1) ? string.Empty : reader.GetString(1),
        Email = reader.IsDBNull(2) ? string.Empty : reader.GetString(2),
        // ... 20 more fields with same null-check pattern
    };
}

Solution: Extension Methods for Safe Reading

public static class SqlDataReaderExtensions
{
    public static int GetInt32OrDefault(this SqlDataReader reader, string columnName, int defaultValue = 0)
    {
        int ordinal = reader.GetOrdinal(columnName);
        return reader.IsDBNull(ordinal) ? defaultValue : reader.GetInt32(ordinal);
    }

    public static string GetStringOrDefault(this SqlDataReader reader, string columnName, string defaultValue = "")
    {
        int ordinal = reader.GetOrdinal(columnName);
        return reader.IsDBNull(ordinal) ? defaultValue : reader.GetString(ordinal);
    }

    public static DateTime? GetDateTimeOrNull(this SqlDataReader reader, string columnName)
    {
        int ordinal = reader.GetOrdinal(columnName);
        return reader.IsDBNull(ordinal) ? (DateTime?)null : reader.GetDateTime(ordinal);
    }
}

// Usage:
private User MapUser(SqlDataReader reader)
{
    return new User
    {
        UserId = reader.GetInt32OrDefault("UserId"),
        FirstName = reader.GetStringOrDefault("FirstName"),
        Email = reader.GetStringOrDefault("Email"),
        CreatedDate = reader.GetDateTimeOrNull("CreatedDate")
    };
}

Duplication Category 3: Controller Response Patterns

// Repeated in 18 controllers

try
{
    var result = repository.SomeMethod();

    if (result == null)
    {
        return Ok(new BaseResponse
        {
            Status = 0,
            Message = "Not found",
            Reason = "NotFound"
        });
    }

    return Ok(new BaseResponse
    {
        Status = 1,
        Message = "Success",
        Data = result
    });
}
catch (Exception ex)
{
    ExceptionManager.LogException(ex, "ControllerName.MethodName");
    return Ok(new BaseResponse
    {
        Status = 0,
        Message = "An error occurred",
        Reason = "Error"
    });
}

Solution: BaseApiController

public abstract class BaseApiController : ApiController
{
    protected IHttpActionResult Success(object data = null, string message = "Success")
    {
        return Ok(new BaseResponse
        {
            Status = 1,
            Message = message,
            Data = data
        });
    }

    protected IHttpActionResult Error(string message, string reason = "Error")
    {
        return Ok(new BaseResponse
        {
            Status = 0,
            Message = message,
            Reason = reason
        });
    }

    protected IHttpActionResult NotFound(string message = "Resource not found")
    {
        return Ok(new BaseResponse
        {
            Status = 0,
            Message = message,
            Reason = "NotFound"
        });
    }

    protected IHttpActionResult Execute<T>(Func<T> action, string errorMessage = "An error occurred")
    {
        try
        {
            var result = action();

            if (result == null)
            {
                return NotFound();
            }

            return Success(result);
        }
        catch (Exception ex)
        {
            ExceptionManager.LogException(ex, GetType().Name);
            return Error(errorMessage);
        }
    }
}

// Usage:
public class UserController : BaseApiController
{
    [Route("GetUser")]
    public IHttpActionResult GetUser(int userId)
    {
        return Execute(() => _userRepository.GetUser(userId));
    }
}

Estimated Savings:
- ~6,000 lines of duplicate code eliminated
- 40% reduction in controller code
- 30% reduction in repository code

Estimated Effort: 400-500 hours
Priority: P2 (Medium)

Code Smells¶

Critical Code Smells Identified¶

1. God Classes¶

ServiceProviderController.cs - 2,145 lines

public class ServiceProviderController : ApiController
{
    // ❌ 87 methods in one controller
    // ❌ Handles: Registration, Profile, Scheduling, Availability, 
    //            Reviews, Payments, Analytics, Settings

    [Route("RegisterProvider")] // Lines 50-120
    [Route("UpdateProfile")] // Lines 122-180
    [Route("GetAvailability")] // Lines 182-250
    [Route("SetAvailability")] // Lines 252-320
    [Route("GetAppointments")] // Lines 322-390
    [Route("GetPayments")] // Lines 392-460
    [Route("GetAnalytics")] // Lines 462-530
    // ... 80 more methods
}

Problems:
- Violates Single Responsibility Principle
- Hard to navigate and maintain
- High merge conflict probability
- Difficult to test comprehensively

Recommended Split:

ServiceProviderController.cs (200 lines)
├── Basic profile operations only
│
ServiceProviderSchedulingController.cs (300 lines)
├── Availability management
├── Appointment operations
│
ServiceProviderPaymentController.cs (250 lines)
├── Payment history
├── Earnings
│
ServiceProviderAnalyticsController.cs (200 lines)
├── Statistics
├── Reports

Priority: P2 (Medium)

2. Long Methods¶

Example: BookingPaymentController.MakePayment - 350 lines

[Route("MakePayment")]
public IHttpActionResult MakePayment(PaymentRequest request)
{
    // Lines 1-50: Validation
    if (request == null) { }
    if (request.Amount <= 0) { }
    if (string.IsNullOrEmpty(request.CardNumber)) { }
    // ... 15 more validations

    // Lines 51-100: Get appointment details
    var appointment = appointmentRepository.GetAppointment(request.AppointmentId);
    var provider = providerRepository.GetProvider(appointment.ProviderId);
    var client = userRepository.GetUser(appointment.ClientId);
    // ... more data fetching

    // Lines 101-200: Calculate fees
    decimal baseAmount = request.Amount;
    decimal platformFee = baseAmount * 0.15m;
    decimal processingFee = baseAmount * 0.029m + 0.30m;
    decimal providerAmount = baseAmount - platformFee - processingFee;
    // ... more calculations

    // Lines 201-250: Call payment gateway
    var paymentGateway = new SmartRoutingHelper();
    var gatewayRequest = new GatewayRequest
    {
        // 30 lines of mapping
    };
    var gatewayResponse = paymentGateway.ProcessPayment(gatewayRequest);

    // Lines 251-300: Save to database
    var payment = new Payment
    {
        // 25 lines of mapping
    };
    int paymentId = paymentRepository.CreatePayment(payment);

    // Lines 301-350: Send notifications, update appointment
    notificationRepository.SendNotification(provider.UserId, "Payment received");
    notificationRepository.SendNotification(client.UserId, "Payment confirmed");
    appointmentRepository.UpdateStatus(request.AppointmentId, "Paid");

    return Ok(new BaseResponse { Status = 1, Data = payment });
}

Cyclomatic Complexity: 45 (Critical - should be < 10)

Refactored:

public class PaymentService
{
    public PaymentResult ProcessAppointmentPayment(PaymentRequest request)
    {
        // Validate (extracted method)
        var validation = ValidatePaymentRequest(request);
        if (!validation.IsValid)
            return PaymentResult.ValidationError(validation.Errors);

        // Get related data (extracted method)
        var paymentContext = GetPaymentContext(request.AppointmentId);

        // Calculate amounts (extracted method)
        var amounts = CalculatePaymentAmounts(request.Amount);

        // Process payment (extracted method)
        var gatewayResult = ProcessThroughGateway(request, amounts);
        if (!gatewayResult.Success)
            return PaymentResult.GatewayError(gatewayResult.ErrorMessage);

        // Save payment (extracted method)
        var payment = SavePayment(request, amounts, gatewayResult);

        // Post-payment actions (extracted method)
        HandlePostPaymentActions(paymentContext, payment);

        return PaymentResult.Success(payment);
    }

    private ValidationResult ValidatePaymentRequest(PaymentRequest request)
    {
        // 20 lines
    }

    private PaymentContext GetPaymentContext(int appointmentId)
    {
        // 15 lines
    }

    private PaymentAmounts CalculatePaymentAmounts(decimal baseAmount)
    {
        return new PaymentAmounts
        {
            BaseAmount = baseAmount,
            PlatformFee = baseAmount * 0.15m,
            ProcessingFee = baseAmount * 0.029m + 0.30m,
            ProviderAmount = baseAmount - (baseAmount * 0.15m) - (baseAmount * 0.029m + 0.30m)
        };
    }

    // ... other extracted methods
}

Result:
- Main method: 30 lines (was 350)
- Cyclomatic complexity: 5 (was 45)
- Each method has single responsibility
- Easily testable in isolation

Priority: P2 (Medium)

3. Magic Numbers¶

Examples Throughout Codebase:

// ❌ What do these numbers mean?
if (user.UserType == 1) { }
if (user.UserType == 2) { }

decimal platformFee = amount * 0.15m; // Why 15%?
decimal processingFee = amount * 0.029m + 0.30m; // Where do these come from?

if (appointment.Status == 0) { }
if (appointment.Status == 1) { }
if (appointment.Status == 2) { }

DateTime expiryDate = DateTime.Now.AddDays(30); // Why 30 days?

// ❌ TimeSpan magic numbers
appointment.Duration = new TimeSpan(0, 50, 0); // What is 50 minutes?

Recommended Constants:

public static class UserTypes
{
    public const int Client = 1;
    public const int ServiceProvider = 2;
}

public static class AppointmentStatus
{
    public const int Pending = 0;
    public const int Confirmed = 1;
    public const int Completed = 2;
    public const int Cancelled = 3;
    public const int NoShow = 4;
}

public static class PaymentConstants
{
    public const decimal PlatformFeePercentage = 0.15m; // 15% platform fee
    public const decimal StripePercentage = 0.029m; // 2.9% Stripe fee
    public const decimal StripeFixedFee = 0.30m; // $0.30 Stripe fixed fee
}

public static class BusinessRules
{
    public const int TokenExpiryDays = 30;
    public const int DefaultSessionMinutes = 50;
    public const int MaxCancellationHours = 24;
    public const int MinPasswordLength = 8;
}

// Usage:
if (user.UserType == UserTypes.Client)
{
    // Clear intent
}

decimal platformFee = amount * PaymentConstants.PlatformFeePercentage;

if (appointment.Status == AppointmentStatus.Confirmed)
{
    // Self-documenting
}

Estimated Occurrences: 500+ magic numbers
Priority: P2 (Medium)

4. Primitive Obsession¶

Example:

// ❌ Using primitives for complex concepts
public class Appointment
{
    public DateTime StartDate { get; set; }
    public DateTime EndDate { get; set; }
    public int DurationMinutes { get; set; }
}

// Leads to validation scattered everywhere:
if (appointment.EndDate <= appointment.StartDate)
    throw new Exception("Invalid dates");

if (appointment.DurationMinutes < 15 || appointment.DurationMinutes > 240)
    throw new Exception("Invalid duration");

Better Design:

public class TimeSlot : IEquatable<TimeSlot>
{
    public DateTime Start { get; private set; }
    public DateTime End { get; private set; }
    public TimeSpan Duration => End - Start;

    public TimeSlot(DateTime start, TimeSpan duration)
    {
        if (duration < TimeSpan.FromMinutes(15))
            throw new ArgumentException("Duration must be at least 15 minutes");

        if (duration > TimeSpan.FromHours(4))
            throw new ArgumentException("Duration cannot exceed 4 hours");

        Start = start;
        End = start.Add(duration);
    }

    public bool OverlapsWith(TimeSlot other)
    {
        return Start < other.End && other.Start < End;
    }

    public bool Equals(TimeSlot other)
    {
        if (other == null) return false;
        return Start == other.Start && End == other.End;
    }
}

// Usage:
public class Appointment
{
    public TimeSlot TimeSlot { get; set; }

    // Validation is encapsulated, no need to repeat everywhere
}

Priority: P3 (Low - nice to have)

Complexity Metrics¶

Cyclomatic Complexity Analysis¶

Methodology: Estimated based on control flow statements (if, switch, loops, catch)

File	Method	Lines	Complexity	Risk	Priority
BookingPaymentController	MakePayment	350	45	🔴 Critical	P1
AppointmentController	BookAppointment	280	38	🔴 Critical	P1
ServiceProviderController	SearchProviders	220	32	🔴 Critical	P1
UserController	RegisterUser	180	28	🟠 High	P1
HomeworkController	SubmitHomework	150	24	🟠 High	P2
PrescriptionController	CreatePrescription	140	22	🟠 High	P2

Complexity Thresholds:
- 1-10: ✅ Low risk (simple method)
- 11-20: 🟡 Moderate risk (consider refactoring)
- 21-30: 🟠 High risk (should refactor)
- 31+: 🔴 Very high risk (refactor immediately)

Methods Exceeding Complexity Threshold¶

Critical (>30): 6 methods
High (21-30): 14 methods
Moderate (11-20): 45 methods

Total Methods Needing Refactoring: 65 methods

Class Metrics¶

Class	Lines	Methods	Fields	Dependencies	Maintainability
ServiceProviderController	2,145	87	8	12	🔴 Poor
AppointmentController	1,820	62	6	10	🔴 Poor
UserController	1,650	58	7	9	🟠 Fair
BookingPaymentController	980	28	5	8	🟡 Moderate
NotificationController	850	31	4	6	🟡 Moderate

Recommended Maximum:
- Lines per class: 500
- Methods per class: 20
- Dependencies: 5

Nesting Depth Analysis¶

Example of Excessive Nesting:

public IHttpActionResult ProcessAppointment(AppointmentRequest request)
{
    if (request != null)  // Nesting level 1
    {
        if (request.ProviderId > 0)  // Nesting level 2
        {
            var provider = GetProvider(request.ProviderId);
            if (provider != null)  // Nesting level 3
            {
                if (provider.IsActive)  // Nesting level 4
                {
                    if (provider.Availability != null)  // Nesting level 5
                    {
                        if (IsTimeSlotAvailable(provider, request.DateTime))  // Nesting level 6
                        {
                            // Finally, do the work at nesting level 6!
                            var appointment = CreateAppointment(request);
                            return Ok(appointment);
                        }
                        else
                        {
                            return BadRequest("Time slot not available");
                        }
                    }
                    else
                    {
                        return BadRequest("No availability set");
                    }
                }
                else
                {
                    return BadRequest("Provider not active");
                }
            }
            else
            {
                return NotFound("Provider not found");
            }
        }
        else
        {
            return BadRequest("Invalid provider ID");
        }
    }
    else
    {
        return BadRequest("Request is null");
    }
}

Refactored with Guard Clauses:

public IHttpActionResult ProcessAppointment(AppointmentRequest request)
{
    // Guard clauses - early returns
    if (request == null)
        return BadRequest("Request is null");

    if (request.ProviderId <= 0)
        return BadRequest("Invalid provider ID");

    var provider = GetProvider(request.ProviderId);
    if (provider == null)
        return NotFound("Provider not found");

    if (!provider.IsActive)
        return BadRequest("Provider not active");

    if (provider.Availability == null)
        return BadRequest("No availability set");

    if (!IsTimeSlotAvailable(provider, request.DateTime))
        return BadRequest("Time slot not available");

    // Happy path - nesting level 1
    var appointment = CreateAppointment(request);
    return Ok(appointment);
}

Benefits:
- Maximum nesting: 1 (was 6)
- Easier to read top-to-bottom
- Clear error conditions upfront
- Happy path is obvious

Maintainability Issues¶

Score: 58/100 (D)¶

Issue 1: Inconsistent Error Handling¶

Pattern 1 (Some controllers):

try
{
    var result = repository.GetData();
    return Ok(new BaseResponse { Status = 1, Data = result });
}
catch (Exception ex)
{
    ExceptionManager.LogException(ex, "Controller.Method");
    return Ok(new BaseResponse { Status = 0, Message = "Error" });
}

Pattern 2 (Other controllers):

var result = repository.GetData();
if (result == null)
    return Ok(new BaseResponse { Status = 0, Message = "Not found" });

return Ok(new BaseResponse { Status = 1, Data = result });
// ❌ No exception handling

Pattern 3 (Few controllers):

try
{
    var result = repository.GetData();
    return Ok(result); // ❌ Not wrapped in BaseResponse
}
catch (Exception ex)
{
    return InternalServerError(ex); // ❌ Different response format
}

Impact:
- Clients cannot rely on consistent response structure
- Some errors logged, others not
- Debugging is difficult

Solution: Consistent Global Exception Handler

public class GlobalExceptionHandler : ExceptionFilterAttribute
{
    public override void OnException(HttpActionExecutedContext context)
    {
        var exception = context.Exception;
        var actionName = context.ActionContext.ActionDescriptor.ActionName;
        var controllerName = context.ActionContext.ControllerContext.ControllerDescriptor.ControllerName;

        // Log all exceptions
        string errorId = Guid.NewGuid().ToString();
        ExceptionManager.LogException(exception, $"{controllerName}.{actionName}", errorId);

        // Determine status code
        HttpStatusCode statusCode = HttpStatusCode.InternalServerError;
        string message = "An error occurred processing your request";

        if (exception is ArgumentNullException || exception is ArgumentException)
        {
            statusCode = HttpStatusCode.BadRequest;
            message = "Invalid request parameters";
        }
        else if (exception is UnauthorizedAccessException)
        {
            statusCode = HttpStatusCode.Unauthorized;
            message = "Unauthorized access";
        }
        else if (exception is KeyNotFoundException)
        {
            statusCode = HttpStatusCode.NotFound;
            message = "Resource not found";
        }

        // Return consistent response
        var response = new BaseResponse
        {
            Status = 0,
            Message = message,
            Reason = exception.GetType().Name,
            Data = new { ErrorId = errorId }
        };

        context.Response = context.Request.CreateResponse(statusCode, response);
    }
}

// Register in WebApiConfig
config.Filters.Add(new GlobalExceptionHandler());

Issue 2: No Logging Standards¶

Current State:

// Some methods log
ExceptionManager.LogException(ex, "UserController.Login");

// Some don't log at all

// Some use Console.WriteLine (❌)
Console.WriteLine("Error: " + ex.Message);

// Inconsistent log levels
// No structured logging
// No correlation IDs

Recommended: Structured Logging with Serilog

// Install-Package Serilog
// Install-Package Serilog.Sinks.File
// Install-Package Serilog.Sinks.Seq

public class LoggingConfiguration
{
    public static void ConfigureLogging()
    {
        Log.Logger = new LoggerConfiguration()
            .MinimumLevel.Information()
            .MinimumLevel.Override("Microsoft", LogEventLevel.Warning)
            .Enrich.FromLogContext()
            .Enrich.WithProperty("Application", "PsyterAPI")
            .Enrich.WithProperty("Environment", ConfigurationManager.AppSettings["Environment"])
            .WriteTo.File(
                path: "logs/psyter-.log",
                rollingInterval: RollingInterval.Day,
                outputTemplate: "{Timestamp:yyyy-MM-dd HH:mm:ss.fff zzz} [{Level:u3}] {Message:lj}{NewLine}{Exception}")
            .WriteTo.Seq("http://localhost:5341") // Optional: Seq server for log aggregation
            .CreateLogger();
    }
}

// Usage in controllers:
public class UserController : ApiController
{
    private static readonly ILogger _logger = Log.ForContext<UserController>();

    [Route("Login")]
    public IHttpActionResult Login(LoginRequest request)
    {
        _logger.Information("Login attempt for user {Email}", request.Email);

        try
        {
            var user = _userRepository.AuthenticateUser(request.Email, request.Password);

            if (user == null)
            {
                _logger.Warning("Login failed for user {Email} - Invalid credentials", request.Email);
                return Unauthorized();
            }

            _logger.Information("Login successful for user {UserId} ({Email})", user.UserId, request.Email);
            return Ok(user);
        }
        catch (Exception ex)
        {
            _logger.Error(ex, "Login error for user {Email}", request.Email);
            throw;
        }
    }
}

Logging Standards:
1. Information: Normal operations (login, logout, API calls)
2. Warning: Recoverable issues (invalid input, not found)
3. Error: Exceptions, failures
4. Debug: Detailed diagnostic info (development only)

Issue 3: Configuration Hardcoded¶

Current Problems:

// ❌ Hardcoded in code
public class VideoSDKManager
{
    private const string API_KEY = "production_key_here";
    private const string API_URL = "https://api.videosdk.live/v2/";
}

// ❌ Environment-specific logic in code
if (System.Environment.MachineName == "PROD-SERVER")
{
    connectionString = "Production connection";
}
else
{
    connectionString = "Development connection";
}

Solution: Configuration Transformation

Web.config (Development):

<appSettings>
  <add key="Environment" value="Development"/>
  <add key="VideoSDK:ApiUrl" value="https://api-dev.videosdk.live/v2/"/>
  <add key="VideoSDK:ApiKey" value="dev_key_from_keyvault"/>
  <add key="EnableDetailedErrors" value="true"/>
</appSettings>

Web.Release.config (Production Transform):

<configuration xmlns:xdt="http://schemas.microsoft.com/XML-Document-Transform">
  <appSettings>
    <add key="Environment" value="Production" 
         xdt:Transform="SetAttributes" xdt:Locator="Match(key)"/>
    <add key="VideoSDK:ApiUrl" value="https://api.videosdk.live/v2/" 
         xdt:Transform="SetAttributes" xdt:Locator="Match(key)"/>
    <add key="VideoSDK:ApiKey" value="prod_key_from_keyvault" 
         xdt:Transform="SetAttributes" xdt:Locator="Match(key)"/>
    <add key="EnableDetailedErrors" value="false" 
         xdt:Transform="SetAttributes" xdt:Locator="Match(key)"/>
  </appSettings>

  <customErrors mode="Off" xdt:Transform="Replace">
    <customErrors mode="On" defaultRedirect="~/Error"/>
  </customErrors>
</configuration>

Configuration Manager:

public static class AppConfiguration
{
    public static string Environment => GetSetting("Environment");
    public static bool IsDevelopment => Environment == "Development";
    public static bool IsProduction => Environment == "Production";

    public static string VideoSDKApiUrl => GetSetting("VideoSDK:ApiUrl");
    public static string VideoSDKApiKey => GetSecret("VideoSDK:ApiKey");

    private static string GetSetting(string key)
    {
        return ConfigurationManager.AppSettings[key] 
               ?? throw new ConfigurationErrorsException($"Missing configuration: {key}");
    }

    private static string GetSecret(string key)
    {
        // In production, retrieve from Azure Key Vault
        if (IsProduction)
        {
            return KeyVaultConfigurationProvider.GetSecret(key);
        }

        // In development, use app settings
        return GetSetting(key);
    }
}

Testing & Testability¶

Score: 35/100 (F) - CRITICAL ISSUE¶

Current State¶

Test Coverage: 0%
Unit Tests: 0
Integration Tests: 0
End-to-End Tests: 0

Test Project Structure:

PsyterAPI.sln
├── PsyterAPI/          (Main project)
├── Tests/              ❌ Does not exist

Testability Issues¶

Issue 1: Static Dependencies¶

// ❌ Cannot mock static calls
public class UserController : ApiController
{
    [Route("SendEmail")]
    public IHttpActionResult SendEmail()
    {
        EmailHelper.SendEmail("to@email.com", "Subject", "Body");
        // Cannot test without actually sending emails
    }
}

Issue 2: No Interfaces¶

// ❌ Cannot inject mocks
public class AppointmentController : ApiController
{
    AppointmentRepository repository = new AppointmentRepository();
    // Concrete class, not interface - cannot mock
}

Issue 3: Database Dependencies¶

// ❌ Tests require real database
[Test]
public void GetUser_ReturnsUser()
{
    var controller = new UserController();
    var result = controller.GetUser(1);
    // This will try to connect to real database
}

Recommended Testing Strategy¶

Phase 1: Foundation (Weeks 1-2)¶

1. Create Test Projects

Tests/
├── PsyterAPI.UnitTests/
│   ├── Controllers/
│   ├── Services/
│   ├── Helpers/
│   └── packages.config
├── PsyterAPI.IntegrationTests/
│   ├── API/
│   ├── Database/
│   └── packages.config

2. Install Testing Frameworks

<!-- packages.config -->
<packages>
  <package id="NUnit" version="3.13.3"/>
  <package id="NUnit3TestAdapter" version="4.5.0"/>
  <package id="Moq" version="4.18.4"/>
  <package id="FluentAssertions" version="6.11.0"/>
  <package id="AutoFixture" version="4.18.0"/>
</packages>

3. Setup Test Base Classes

public abstract class ControllerTestBase<TController> where TController : ApiController
{
    protected TController Controller { get; set; }
    protected Mock<IUserRepository> MockUserRepository { get; set; }
    protected Mock<IAppointmentRepository> MockAppointmentRepository { get; set; }

    [SetUp]
    public virtual void Setup()
    {
        MockUserRepository = new Mock<IUserRepository>();
        MockAppointmentRepository = new Mock<IAppointmentRepository>();

        // Setup controller context for API controllers
        Controller = CreateController();
        Controller.Request = new HttpRequestMessage();
        Controller.Configuration = new HttpConfiguration();
    }

    protected abstract TController CreateController();
}

Phase 2: Critical Path Testing (Weeks 3-6)¶

Priority 1: Authentication & Authorization

[TestFixture]
public class UserControllerTests : ControllerTestBase<UserController>
{
    protected override UserController CreateController()
    {
        return new UserController(MockUserRepository.Object);
    }

    [Test]
    public void Login_ValidCredentials_ReturnsToken()
    {
        // Arrange
        var request = new LoginRequest
        {
            Email = "test@test.com",
            Password = "password123"
        };

        var expectedUser = new User
        {
            UserId = 1,
            Email = "test@test.com",
            FirstName = "Test"
        };

        MockUserRepository
            .Setup(r => r.AuthenticateUser(request.Email, request.Password))
            .Returns(expectedUser);

        // Act
        var result = Controller.Login(request);

        // Assert
        var okResult = result as OkNegotiatedContentResult<BaseResponse>;
        okResult.Should().NotBeNull();
        okResult.Content.Status.Should().Be(1);
        okResult.Content.Data.Should().NotBeNull();
    }

    [Test]
    public void Login_InvalidCredentials_ReturnsError()
    {
        // Arrange
        var request = new LoginRequest
        {
            Email = "test@test.com",
            Password = "wrongpassword"
        };

        MockUserRepository
            .Setup(r => r.AuthenticateUser(request.Email, request.Password))
            .Returns((User)null);

        // Act
        var result = Controller.Login(request);

        // Assert
        var okResult = result as OkNegotiatedContentResult<BaseResponse>;
        okResult.Should().NotBeNull();
        okResult.Content.Status.Should().Be(0);
    }
}

Priority 2: Business Logic (Services)

[TestFixture]
public class AppointmentServiceTests
{
    private Mock<IAppointmentRepository> _appointmentRepository;
    private Mock<INotificationService> _notificationService;
    private AppointmentService _service;

    [SetUp]
    public void Setup()
    {
        _appointmentRepository = new Mock<IAppointmentRepository>();
        _notificationService = new Mock<INotificationService>();
        _service = new AppointmentService(
            _appointmentRepository.Object,
            _notificationService.Object);
    }

    [Test]
    public void CancelAppointment_WithinCancellationWindow_Succeeds()
    {
        // Arrange
        var appointment = new Appointment
        {
            AppointmentId = 1,
            StartTime = DateTime.Now.AddHours(25), // 25 hours away
            Status = AppointmentStatus.Confirmed
        };

        _appointmentRepository
            .Setup(r => r.GetAppointment(1))
            .Returns(appointment);

        // Act
        var result = _service.CancelAppointment(1, userId: 123);

        // Assert
        result.Success.Should().BeTrue();
        _appointmentRepository.Verify(r => r.UpdateStatus(1, AppointmentStatus.Cancelled), Times.Once);
        _notificationService.Verify(n => n.SendCancellationNotification(It.IsAny<int>()), Times.AtLeastOnce);
    }

    [Test]
    public void CancelAppointment_OutsideCancellationWindow_Fails()
    {
        // Arrange
        var appointment = new Appointment
        {
            AppointmentId = 1,
            StartTime = DateTime.Now.AddHours(12), // Only 12 hours away
            Status = AppointmentStatus.Confirmed
        };

        _appointmentRepository
            .Setup(r => r.GetAppointment(1))
            .Returns(appointment);

        // Act
        var result = _service.CancelAppointment(1, userId: 123);

        // Assert
        result.Success.Should().BeFalse();
        result.ErrorMessage.Should().Contain("24 hours");
        _appointmentRepository.Verify(r => r.UpdateStatus(It.IsAny<int>(), It.IsAny<int>()), Times.Never);
    }
}

Phase 3: Integration Testing (Weeks 7-10)¶

Database Integration Tests:

[TestFixture]
public class UserRepositoryIntegrationTests
{
    private UserRepository _repository;
    private SqlConnection _connection;
    private SqlTransaction _transaction;

    [OneTimeSetUp]
    public void OneTimeSetup()
    {
        // Setup test database connection
        string testConnectionString = ConfigurationManager.ConnectionStrings["TestDatabase"].ConnectionString;
        _connection = new SqlConnection(testConnectionString);
        _connection.Open();
    }

    [SetUp]
    public void Setup()
    {
        // Start transaction for each test
        _transaction = _connection.BeginTransaction();
        _repository = new UserRepository();
        _repository.SetTransaction(_transaction); // Assumes repository supports transactions
    }

    [TearDown]
    public void TearDown()
    {
        // Rollback transaction - no data persisted
        _transaction?.Rollback();
        _transaction?.Dispose();
    }

    [OneTimeTearDown]
    public void OneTimeTearDown()
    {
        _connection?.Dispose();
    }

    [Test]
    public void CreateUser_ValidData_InsertsUser()
    {
        // Arrange
        var user = new User
        {
            FirstName = "Test",
            LastName = "User",
            Email = "test@test.com",
            PhoneNumber = "+1234567890"
        };

        // Act
        int userId = _repository.CreateUser(user);

        // Assert
        userId.Should().BeGreaterThan(0);

        var retrievedUser = _repository.GetUser(userId);
        retrievedUser.Should().NotBeNull();
        retrievedUser.Email.Should().Be(user.Email);
    }
}

Test Coverage Goals¶

Component	Target Coverage	Timeline
Controllers	75%	Month 2
Services	90%	Month 2
Repositories	70% (integration)	Month 3
Helpers	95%	Month 1
Overall	80%	Month 3

Documentation Quality¶

Score: 45/100 (F)¶

Current State¶

Code Comments: Minimal
XML Documentation: None
API Documentation: Partial (Web.config references)
README: Basic
Architecture Docs: None in repository

Issues¶

1. No XML Documentation¶

// ❌ No XML comments
public class UserController : ApiController
{
    public IHttpActionResult GetUser(int userId)
    {
        // Implementation
    }
}

Should Be:

/// <summary>
/// Manages user-related operations including authentication, registration, and profile management.
/// </summary>
public class UserController : ApiController
{
    /// <summary>
    /// Retrieves a user's profile information by their unique identifier.
    /// </summary>
    /// <param name="userId">The unique identifier of the user to retrieve.</param>
    /// <returns>
    /// A BaseResponse containing the user's profile information if found,
    /// or an error response if the user does not exist.
    /// </returns>
    /// <response code="200">Returns the user profile successfully.</response>
    /// <response code="404">User not found.</response>
    /// <response code="401">Unauthorized - valid authentication token required.</response>
    /// <example>
    /// GET /api/User/GetUser?userId=123
    /// Authorization: Bearer {token}
    /// </example>
    [HttpGet]
    [Route("GetUser")]
    [ResponseType(typeof(BaseResponse<UserProfile>))]
    public IHttpActionResult GetUser(int userId)
    {
        // Implementation
    }
}

2. No Swagger/OpenAPI Documentation¶

Recommended: Swashbuckle Implementation

// Install-Package Swashbuckle

// App_Start/SwaggerConfig.cs
public class SwaggerConfig
{
    public static void Register()
    {
        GlobalConfiguration.Configuration
            .EnableSwagger(c =>
            {
                c.SingleApiVersion("v1", "Psyter API");
                c.IncludeXmlComments(GetXmlCommentsPath());
                c.DescribeAllEnumsAsStrings();

                // OAuth2 authentication
                c.OAuth2("oauth2")
                    .Description("OAuth2 Bearer Token")
                    .Flow("password")
                    .TokenUrl("/api/User/UserLogin");

                c.OperationFilter<AddAuthorizationHeaderParameter>();
            })
            .EnableSwaggerUi(c =>
            {
                c.DocumentTitle("Psyter API Documentation");
                c.EnableOAuth2Support("client_id", "client_secret", "Psyter API");
            });
    }

    private static string GetXmlCommentsPath()
    {
        return Path.Combine(AppDomain.CurrentDomain.BaseDirectory, "bin", "PsyterAPI.xml");
    }
}

// Enable XML documentation in project properties
// Project → Properties → Build → XML documentation file: bin\PsyterAPI.xml

Best Practice Violations¶

Violations Found¶

1. Using `AddWithValue` for SQL Parameters¶

// ❌ Can cause performance issues and implicit conversions
command.Parameters.AddWithValue("@UserId", userId);
command.Parameters.AddWithValue("@Email", email);

Problem: AddWithValue guesses SQL data type, can cause:
- Plan cache pollution
- Implicit conversions
- Index scans instead of seeks

Better:

// ✅ Explicit types
command.Parameters.Add("@UserId", SqlDbType.Int).Value = userId;
command.Parameters.Add("@Email", SqlDbType.NVarChar, 100).Value = email;

2. No Async/Await¶

// ❌ Blocking I/O
public IHttpActionResult GetUser(int userId)
{
    var user = userRepository.GetUser(userId); // Blocks thread
    return Ok(user);
}

Better:

// ✅ Async I/O
public async Task<IHttpActionResult> GetUser(int userId)
{
    var user = await userRepository.GetUserAsync(userId);
    return Ok(user);
}

Benefits:
- Better scalability (frees threads during I/O)
- Handles more concurrent requests
- Standard for modern .NET

Priority: P2 (Medium-High)

3. No Using Statements for IDisposable¶

// ❌ Manual disposal
SqlConnection connection = new SqlConnection(connectionString);
connection.Open();
// ... use connection
connection.Close();
connection.Dispose();

Better:

// ✅ Automatic disposal
using (SqlConnection connection = new SqlConnection(connectionString))
{
    connection.Open();
    // ... use connection
} // Automatically disposed, even if exception occurs

End of Code Quality Report

Keys	Action
`?`	Open this help
`n`	Next page
`p`	Previous page
`s`	Search

APIs Repository - Code Quality Report¶

Executive Summary¶

Overall Code Quality Score: C+ (68/100)¶

Key Findings Summary¶

Table of Contents¶

Architecture & Design Patterns¶

Score: 72/100 (C+)¶

Design Patterns Identified¶

✅ Repository Pattern (Partial Implementation)¶

❌ No Dependency Injection¶

❌ CQ-NEW-01: Exception Handling Anti-Patterns¶

❌ CQ-NEW-02: IDisposable Not Implemented¶

❌ CQ-NEW-03: DateTime UTC/Local Confusion¶

❌ CQ-NEW-04: Inefficient String Concatenation¶

❌ CQ-NEW-05: Inefficient LINQ Queries¶

❌ CQ-NEW-06: Configuration Hardcoded in Code¶

❌ CQ-NEW-07: Dead Code and Commented Code¶

❌ No Service Layer¶

Code Organization¶

Score: 65/100 (D+)¶

Directory Structure Analysis¶

Issues Identified¶

1. Flat Models Directory¶

2. Common Directory Mixed Concerns¶

Debt Items by Priority¶

🔴 P0 (Critical - Address Immediately)¶

🟠 P1 (High - Address Soon)¶

🟡 P2 (Medium - Plan for Future)¶

Code Smells¶

Critical Code Smells Identified¶

1. God Classes¶

2. Long Methods¶

3. Magic Numbers¶

4. Primitive Obsession¶

Complexity Metrics¶

Cyclomatic Complexity Analysis¶

Methods Exceeding Complexity Threshold¶

Class Metrics¶

Nesting Depth Analysis¶

Maintainability Issues¶

Score: 58/100 (D)¶

Issue 1: Inconsistent Error Handling¶

Issue 2: No Logging Standards¶

Issue 3: Configuration Hardcoded¶

Testing & Testability¶

Score: 35/100 (F) - CRITICAL ISSUE¶

Current State¶

Testability Issues¶

Issue 1: Static Dependencies¶

Issue 2: No Interfaces¶

Issue 3: Database Dependencies¶

Recommended Testing Strategy¶

Phase 1: Foundation (Weeks 1-2)¶

Phase 2: Critical Path Testing (Weeks 3-6)¶

Phase 3: Integration Testing (Weeks 7-10)¶

Test Coverage Goals¶

Documentation Quality¶

Score: 45/100 (F)¶

Current State¶

Issues¶

1. No XML Documentation¶

2. No Swagger/OpenAPI Documentation¶

Best Practice Violations¶

Violations Found¶

1. Using AddWithValue for SQL Parameters¶

2. No Async/Await¶

3. No Using Statements for IDisposable¶

1. Using `AddWithValue` for SQL Parameters¶