almost done need upload file for activity

src/APIMappers/ActivityMapper.cs

@@ -8,7 +8,7 @@ public static class ActivityMapper
 {
     private static GenericMapper<Activity, ActivityDto> _mapper = new GenericMapper<Activity, ActivityDto>();
     
-    public static ActivityDto? ToDto(this Activity activity)
+    public static ActivityDto ToDto(this Activity activity)
     {
         return activity.ToU(_mapper, activityDto => new ActivityDto
         {
@@ -29,7 +29,7 @@ public static class ActivityMapper
         });
     }
     
-    public static Activity? ToModel(this ActivityDto activityDto)
+    public static Activity ToModel(this ActivityDto activityDto)
     {
         return activityDto.ToT(_mapper, activity => new Activity
         {

src/APIMappers/UserMappeur.cs

@@ -8,7 +8,7 @@ public static class UserMappeur
 {
     private static GenericMapper<User, UserDto> _mapper = new GenericMapper<User, UserDto>();
 
-    public static UserDto? ToDto(this User user)
+    public static UserDto ToDto(this User user)
     {
         return user.ToU(_mapper, userDto =>  new UserDto
         {
@@ -32,7 +32,7 @@ public static class UserMappeur
     // corégraphie => microservice TCP
     
 
-    public static User? ToModel(this UserDto userDto)
+    public static User ToModel(this UserDto userDto)
     {
         return userDto.ToT(_mapper, user => new User
         {

src/HeartTrackAPI/AppBootstrap.cs

@@ -11,6 +11,7 @@ using Microsoft.Extensions.Options;
 using Microsoft.OpenApi.Models;
 using Model.Manager;
 using Model2Entities;
+using StubAPI;
 
 namespace HeartTrackAPI;
 
@@ -68,7 +69,8 @@ public class AppBootstrap(IConfiguration configuration)
     }
     private void AddModelService(IServiceCollection services)
     {
-        services.AddSingleton<IDataManager>(provider => new DbDataManager(provider.GetService<HeartTrackContext>()));
+        //services.AddSingleton<IDataManager>(provider => new DbDataManager(provider.GetService<HeartTrackContext>()));
+        services.AddSingleton<IDataManager, StubData>();
         //services.AddTransient<IActivityManager, ActivityManager>();
     }
 

src/HeartTrackAPI/Controllers/ActivityController.cs

@@ -3,8 +3,8 @@ using Dto;
 using HeartTrackAPI.Request;
 using HeartTrackAPI.Responce;
 using Microsoft.AspNetCore.Mvc;
-using Shared;
 using Model;
+using Shared;
 using Model.Manager;
 using Model.Repository;
 
@@ -40,7 +40,7 @@ public class ActivityController : Controller
             var activities = await _activityService.GetActivities(pageRequest.Index, pageRequest.Count, ActivityOrderCriteria.None, pageRequest.Descending ?? false);
             if(activities == null)
             {
-                return BadRequest("No activities found");
+                return NotFound("No activities found");
             }
             var pageResponse = new PageResponse<ActivityDto>(pageRequest.Index, pageRequest.Count, totalCount, activities.Select(a => a.ToDto()));
             return Ok(pageResponse);
@@ -52,22 +52,61 @@ public class ActivityController : Controller
         }
     }
     /*
-    public async Task<IActionResult> PostFitFile([FromForm] IFormFile file)
-    {
+    [HttpPost]
+    [ProducesResponseType(StatusCodes.Status201Created)]
+    [ProducesResponseType(StatusCodes.Status415UnsupportedMediaType)]
+    [MultipartFormData]
+    [DisableFormValueModelBinding]
+    public async Task<IActionResult> PostFitFile( Stream file, string contentType) // [FromForm]
+    {
+        if (!MultipartRequestHelper.IsMultipartContentType(Request.ContentType))
+        {
+            ModelState.AddModelError("File", 
+                $"The request couldn't be processed (Error 1).");
+            // Log error
+
+            return BadRequest(ModelState);
+        }
         if (file == null)
         {
             return BadRequest("No file was provided");
         }
-        var activity = await _activityManager.AddActivityFromFitFile(file);
-        à l'intérieur du   AddActivityFromFitFile ya un truc comme     var result = await _activityRepo.AddActivity(activity);
-
+        //var fileUploadSummary = await _fileService.UploadFileAsync(HttpContext.Request.Body, Request.ContentType);
+//        var activity = await _activityManager.AddActivityFromFitFile(file);
+        var activity = new Activity
+        {
+            Id = 1,
+            Type = "Running",
+            Date = new DateTime(2021, 10, 10),
+            StartTime = new DateTime(2021, 10, 10, 10, 0, 0),
+            EndTime = new DateTime(2021, 10, 10, 11, 0, 0),
+            Effort = 3,
+            Variability = 0.5f,
+            Variance = 0.5f,
+            StandardDeviation = 0.5f,
+            Average = 5.0f,
+            Maximum = 10,
+            Minimum = 0,
+            AverageTemperature = 20.0f,
+            HasAutoPause = false,
+            Users =
+            {
+                new User
+                {
+                    Id = 3, Username = "Athlete3",
+                    ProfilePicture =
+                        "https://plus.unsplash.com/premium_photo-1705091981693-6006f8a20479?q=80&w=1974&auto=format&fit=crop&ixlib=rb-4.0.3&ixid=M3wxMjA3fDB8MHxwaG90by1wYWdlfHx8fGVufDB8fHx8fA%3D%3D",
+                    FirstName = "First3", LastName = "Last3",
+                    Sexe = "M", Lenght = 190, Weight = 80, DateOfBirth = new DateTime(1994, 3, 3), Email = "ath@ex.fr",
+                    Role = new Athlete()
+                }
+            }
+        };
         if (activity == null)
         {
             return BadRequest("The file provided is not a valid fit file");
         }
-        return CreatedAtAction(nameof(GetActivity), new { id = result.Id }, result.ToDto());
-
-        return CreatedAtAction(nameof(GetActivities), activity.ToDto());
+        return CreatedAtAction(nameof(GetActivity), new { id = activity.Id }, activity.ToDto());
     }*/
     
     [HttpGet("{id}")]
@@ -107,4 +146,34 @@ public class ActivityController : Controller
         }
         return NoContent();
     }
+    
+/*
+    public async Task<FileUploadSummary> UploadFileAsync(Stream fileStream, string contentType)
+    {
+        var fileCount = 0;
+        long totalSizeInBytes = 0;
+        var boundary = GetBoundary(MediaTypeHeaderValue.Parse(contentType));
+        var multipartReader = new MultipartReader(boundary, fileStream);
+        var section = await multipartReader.ReadNextSectionAsync();
+        var filePaths = new List<string>();
+        var notUploadedFiles = new List<string>();
+    
+        while (section != null)
+        {
+            var fileSection = section.AsFileSection();
+            if (fileSection != null)
+            {
+                totalSizeInBytes += await SaveFileAsync(fileSection, filePaths, notUploadedFiles);
+                fileCount++;
+            }
+            section = await multipartReader.ReadNextSectionAsync();
+        }
+        return new FileUploadSummary
+        {
+            TotalFilesUploaded = fileCount,
+            TotalSizeUploaded = ConvertSizeToString(totalSizeInBytes),
+            FilePaths = filePaths,
+            NotUploadedFiles = notUploadedFiles
+        };
+    }*/
 }

src/HeartTrackAPI/Controllers/UsersController.cs

@@ -1,11 +1,9 @@
 using APIMappers;
 using Dto;
-using Entities;
 using HeartTrackAPI.Request;
 using HeartTrackAPI.Responce;
 using Microsoft.AspNetCore.Identity;
 using Microsoft.AspNetCore.Mvc;
-using Model;
 using Model.Manager;
 using Model.Repository;
 using Shared;
@@ -18,11 +16,13 @@ namespace HeartTrackAPI.Controllers;
 public class UsersController : Controller
 {
     private readonly ILogger<UsersController> _logger;
+    private readonly IActivityRepository _activityService;
     private readonly IUserRepository _userService;
     public UsersController(ILogger<UsersController> logger, IDataManager dataManager)
     {
         _logger = logger;
         _userService = dataManager.UserRepo;
+        _activityService = dataManager.ActivityRepo;
     }
 
     [HttpGet]
@@ -43,7 +43,7 @@ public class UsersController : Controller
             _logger.LogInformation("Executing {Action} with parameters: {Parameters}", nameof(Get), null);
            
             var athletes = await _userService.GetUsers(request.Index, request.Count, Enum.TryParse(request.OrderingPropertyName, out AthleteOrderCriteria result) ? result : AthleteOrderCriteria.None, request.Descending ?? false);
-            var pageResponse = new PageResponse<UserDto>(request.Index, request.Count, totalCount, athletes.Select(a => a.ToDto()));
+            var pageResponse = new PageResponse<UserDto>(request.Index, request.Count, totalCount, athletes!.Select(a => a.ToDto()));
             return Ok(pageResponse);
         }
         catch (Exception e)
@@ -118,7 +118,6 @@ public class UsersController : Controller
                  return StatusCode(500);
             }
             return Ok(updatedAthlete.ToDto());
-            return Ok();
 
         }
         catch (Exception e)
@@ -160,6 +159,39 @@ public class UsersController : Controller
         }
     }
     
+    [HttpGet("{id}/friends")]
+    [ProducesResponseType(typeof(PageResponse<UserDto>), 200)]
+    [ProducesResponseType(404)]
+    [ProducesResponseType(500)]
+    public async Task<ActionResult<PageResponse<UserDto>>> GetFriends(int id, [FromQuery] PageRequest request)
+    {
+        try
+        {
+            _logger.LogInformation("Executing {Action} with parameters: {Parameters} for {Id}", nameof(GetFriends), null,id);
+            var athlete = await _userService.GetItemById(id);
+            if (athlete == null)
+            {
+                _logger.LogError("Athlete with id {id} not found", id);
+                return NotFound($"Athlete with id {id} not found");
+            }
+            var totalCount = await _userService.GetNbFriends(athlete);
+            if (request.Count * request.Index >= totalCount)
+            {
+                _logger.LogError("To many object is asked the max is {totalCount} but the request is superior of ", totalCount);
+                return BadRequest("To many object is asked the max is : " + totalCount);
+            }
+            var friends = await _userService.GetFriends(athlete, request.Index, request.Count, Enum.TryParse(request.OrderingPropertyName, out AthleteOrderCriteria result) ? result : AthleteOrderCriteria.None, request.Descending ?? false);
+            if (friends == null) return NotFound();
+            var pageResponse = new PageResponse<UserDto>(request.Index, request.Count, totalCount, friends.Select(a => a.ToDto()));
+            return Ok(pageResponse);
+        }
+        catch (Exception e)
+        {
+            _logger.LogError(e, "Error while getting the number of users");
+            return StatusCode(500);
+        }
+    }
+    
     
     [HttpPost("{id}/friend/{friendId}")]
     [ProducesResponseType(200)]
@@ -197,6 +229,115 @@ public class UsersController : Controller
         }
     }
     
+    [HttpDelete("{id}/friend/{friendId}")]
+    [ProducesResponseType(200)]
+    [ProducesResponseType(404)]
+    [ProducesResponseType(500)]
+    public async Task<IActionResult> RemoveFriend(int id, int friendId)
+    {
+        try
+        {
+            _logger.LogInformation("Executing {Action} with parameters: {Parameters} for {Id}", nameof(RemoveFriend), friendId,id);
+            var athlete = await _userService.GetItemById(id);
+            if (athlete == null)
+            {
+                _logger.LogError("Athlete with id {id} not found", id);
+                return NotFound($"Athlete with id {id} not found");
+            }
+            var friend = await _userService.GetItemById(friendId);
+            if (friend == null)
+            {
+                _logger.LogError("Athlete with id {id} not found", friendId);
+                return NotFound($"Athlete with id {friendId} not found");
+            }
+            var isRemoved = await _userService.RemoveFriend(athlete, friend);
+            if(!isRemoved)
+            {
+                _logger.LogError("Error while removing friend with id {friendId} to athlete with id {id}", friendId, id);
+                return StatusCode(500);
+            }
+            return Ok();
+        }
+        catch (Exception e)
+        {
+            _logger.LogError(e, "Error while getting the number of users");
+            return StatusCode(500);
+        }
+    }
+    
+    
+    // ou faire un get qui si le role est coach resend les athletes et si le role est athlete resend les coach
+    [HttpGet("{coachId}/athletes")]
+    [ProducesResponseType(typeof(PageResponse<UserDto>), 200)]
+    [ProducesResponseType(404)]
+    [ProducesResponseType(500)]
+    public async Task<ActionResult<PageResponse<UserDto>>> GetAthletes(int coachId, [FromQuery] PageRequest request)
+    {
+        try
+        {
+            _logger.LogInformation("Executing {Action} with parameters: {Parameters} for {Id}", nameof(GetAthletes), null,coachId);
+            var coach = await _userService.GetItemById(coachId);
+            if (coach == null)
+            {
+                _logger.LogError("Athlete with id {id} not found", coachId);
+                return NotFound($"Athlete with id {coachId} not found");
+            }
+            var totalCount = await _userService.GetNbFriends(coach);
+            if (request.Count * request.Index >= totalCount)
+            {
+                _logger.LogError("To many object is asked the max is {totalCount} but the request is superior of ", totalCount);
+                return BadRequest("To many object is asked the max is : " + totalCount);
+            }
+            var athletes = await _userService.GetFriends(coach, request.Index, request.Count, Enum.TryParse(request.OrderingPropertyName, out AthleteOrderCriteria result) ? result : AthleteOrderCriteria.None, request.Descending ?? false);
+            if (athletes == null) return NotFound();
+            var pageResponse = new PageResponse<UserDto>(request.Index, request.Count, totalCount, athletes.Select(a => a.ToDto()));
+            return Ok(pageResponse);
+        }
+        catch (Exception e)
+        {
+            _logger.LogError(e, "Error while getting the number of users");
+            return StatusCode(500);
+        }
+    }
+    
+    [HttpGet("{userId}/activities")]
+    // should be tiny DTOActivity returned with only the necessary information (will be used in the list of activities of a user)
+    public async Task<ActionResult<PageResponse<ActivityDto>>> GetActivitiesByUser(int userId, [FromQuery] PageRequest pageRequest)
+    {
+        try
+        {
+            var totalCount = await _activityService.GetNbActivitiesByUser(userId);
+            if (pageRequest.Count * pageRequest.Index >= totalCount)
+            {
+                _logger.LogError("To many object is asked the max is {totalCount} but the request is superior of ", totalCount);
+                return BadRequest("To many object is asked the max is : " + totalCount);
+            }
+            _logger.LogInformation("Executing {Action} with parameters: {Parameters}", nameof(GetActivitiesByUser), pageRequest);
+            var activities = await _activityService.GetActivitiesByUser(userId, pageRequest.Index, pageRequest.Count, ActivityOrderCriteria.None, pageRequest.Descending ?? false);
+            if(activities == null)
+            {
+                return NotFound("No activities found");
+            }
+            var pageResponse = new PageResponse<ActivityDto>(pageRequest.Index, pageRequest.Count, totalCount, activities.Select(a => a.ToDto()));
+            return Ok(pageResponse);
+        }
+        catch (Exception e)
+        {
+            _logger.LogError(e, "Error while getting all activities");
+            return StatusCode(500);
+        }
+    }
+    /*
+    
+    [HttpGet("{userId}/trainings")]
+    [ProducesResponseType(typeof(PageResponse<TrainingDto>), 200)]
+    [ProducesResponseType(404)]
+    [ProducesResponseType(500)]
+public async Task<ActionResult<PageResponse<TrainingDto>> GetTrainings(int userId, [FromQuery] PageRequest request)
+    */
+    
+    
+    
     [HttpPost("logout")]
     [ProducesResponseType(200)]
     [ProducesResponseType(401)]

src/HeartTrackAPI/Dockerfile

@@ -12,7 +12,8 @@ COPY ["StubbedContextLib/StubbedContextLib.csproj", "StubbedContextLib/"]
 COPY ["Shared/Shared.csproj", "Shared/"]
 COPY ["Entities/Entities.csproj", "Entities/"]
 COPY ["Dto/Dto.csproj", "Dto/"]
-COPY ["ApiMappeur/ApiMappeur.csproj", "ApiMappeur/"]
+COPY ["APIMappers/APIMappers.csproj", "APIMappers/"]
+COPY ["EFMappers/EFMappers.csproj", "EFMappers/"]
 COPY ["DbContextLib/DbContextLib.csproj", "DbContextLib/"]
 COPY ["Model/Model.csproj", "Model/"]
 COPY ["Model2Entities/Model2Entities.csproj", "Model2Entities/"]

src/HeartTrackAPI/FileUploadSummary.cs

@@ -0,0 +1,44 @@
+using Microsoft.AspNetCore.Mvc;
+using Microsoft.AspNetCore.Mvc.Filters;
+using Microsoft.AspNetCore.Mvc.ModelBinding;
+
+namespace HeartTrackAPI;
+
+public class FileUploadSummary
+{
+    public int TotalFilesUploaded { get; set; }
+    public string TotalSizeUploaded { get; set; }
+    public IList<string> FilePaths { get; set; } = new List<string>();
+    public IList<string> NotUploadedFiles { get; set; } = new List<string>();
+}
+[AttributeUsage(AttributeTargets.Method | AttributeTargets.Class)]
+public class MultipartFormDataAttribute : ActionFilterAttribute
+{
+    public override void OnActionExecuting(ActionExecutingContext context)
+    {
+        var request = context.HttpContext.Request;
+
+        if (request.HasFormContentType 
+            && request.ContentType.StartsWith("multipart/form-data", StringComparison.OrdinalIgnoreCase))
+        {
+            return;
+        }
+
+        context.Result = new StatusCodeResult(StatusCodes.Status415UnsupportedMediaType);
+    }
+}
+[AttributeUsage(AttributeTargets.Class | AttributeTargets.Method)]
+public class DisableFormValueModelBindingAttribute : Attribute, IResourceFilter
+{
+    public void OnResourceExecuting(ResourceExecutingContext context)
+    {
+        var factories = context.ValueProviderFactories;
+        factories.RemoveType<FormValueProviderFactory>();
+        factories.RemoveType<FormFileValueProviderFactory>();
+        factories.RemoveType<JQueryFormValueProviderFactory>();
+    }
+
+    public void OnResourceExecuted(ResourceExecutedContext context)
+    {
+    }
+}

src/HeartTrackAPI/Program.cs

@@ -4,6 +4,10 @@ using HeartTrackAPI;
 var builder = WebApplication.CreateBuilder(args);
 
 builder.Logging.AddConsole();
+builder.WebHost.ConfigureKestrel(serverOptions =>
+{
+    serverOptions.Limits.MaxRequestBodySize = long.MaxValue;
+});
 
 var init = new AppBootstrap(builder.Configuration);
 

src/Model/Activity.cs

@@ -32,6 +32,7 @@ public class Activity
         public float AverageTemperature { get; set; }
         public bool HasAutoPause { get; set; }
         
+        public HashSet<User> Users { get; private set; } = new HashSet<User>();
         public Activity(int idActivity ,string type, DateTime date, DateTime startTime, DateTime endTime,
                         int effort, float variability, float variance, float standardDeviation,
                         float average, int maximum, int minimum, float averageTemperature, bool hasAutoPause)

src/Model/Repository/IActivityRepository.cs

@@ -4,10 +4,12 @@ namespace Model.Repository;
 
 public interface IActivityRepository
 {
-    public Task<IEnumerable<Activity>> GetActivities(int index, int count, ActivityOrderCriteria criteria, bool descending = false);
+    public Task<IEnumerable<Activity>?> GetActivities(int index, int count, ActivityOrderCriteria criteria, bool descending = false);
     public Task<Activity?> GetActivityByIdAsync(int id);
     public Task<Activity?> AddActivity(Activity activity);
     public Task<Activity?> UpdateActivity(int id, Activity activity);
     public Task<bool> DeleteActivity(int id);
     public Task<int> GetNbItems();
+    public Task<IEnumerable<Activity>?> GetActivitiesByUser(int userId, int index, int count, ActivityOrderCriteria orderCriteria, bool descending= false);
+    public Task<int> GetNbActivitiesByUser(int userId);
 }

src/Model/Repository/IUserRepository.cs

@@ -4,7 +4,14 @@ namespace Model.Repository;
 
 public interface IUserRepository : IGenericRepository<User>
 {
-    public Task<IEnumerable<User>> GetUsers(int index, int count, AthleteOrderCriteria? criteria , bool descending = false);
+    public Task<IEnumerable<User>?> GetUsers(int index, int count, AthleteOrderCriteria? criteria , bool descending = false);
     
     public Task<bool> AddFriend(User user, User friend);
+    
+    public Task<bool> RemoveFriend(User user, User friend);
+    
+    // should be removed cause i just have to call the GetItem then get the friends
+    public Task<IEnumerable<User>?> GetFriends(User user, int index, int count, AthleteOrderCriteria? criteria, bool descending = false);
+    
+    public Task<int> GetNbFriends(User user);
 }

src/Model2Entities/ActivityRepository.cs

@@ -121,5 +121,15 @@ public partial class DbDataManager : IDataManager
                 throw;
             }
         }
+
+        public Task<IEnumerable<Activity>> GetActivitiesByUser(int userId, int index, int count, ActivityOrderCriteria criteria, bool descending = false)
+        {
+            throw new NotImplementedException();
+        }
+
+        public Task<int> GetNbActivitiesByUser(int userId)
+        {
+            throw new NotImplementedException();
+        }
     }
 }

src/Model2Entities/UserRepository.cs

@@ -54,5 +54,20 @@ public partial class DbDataManager
         {
             throw new NotImplementedException();
         }
+
+        public async Task<bool> RemoveFriend(User user, User friend)
+        {
+            throw new NotImplementedException();
+        }
+
+        public Task<IEnumerable<User>?>? GetFriends(User user, int index, int count, AthleteOrderCriteria? criteria, bool descending = false)
+        {
+            throw new NotImplementedException();
+        }
+
+        public Task<int> GetNbFriends(User user)
+        {
+            throw new NotImplementedException();
+        }
     }
 }

src/Shared/Extension.cs

@@ -2,7 +2,7 @@ namespace Shared;
 
 public static class Extensions
 {
-    public static U? ToU<T, U>(this T t, GenericMapper<T, U> mapper, Func<T, U> func) where U :class where  T :class
+    public static U ToU<T, U>(this T t, GenericMapper<T, U> mapper, Func<T, U> func) where U :class where  T :class
     {
         var u = mapper.GetU(t);
         if (u != null) {
@@ -14,7 +14,7 @@ public static class Extensions
         return u;
     }
 // , Action<T, U> action
-    public static T? ToT<T,U>(this U u, GenericMapper<T, U> mapper, Func<U, T> func) where U :class where  T :class
+    public static T ToT<T,U>(this U u, GenericMapper<T, U> mapper, Func<U, T> func) where U :class where  T :class
     {
         var t = mapper.GetT(u);
         if (t != null) {

src/StubAPI/ActivityService.cs

@@ -6,33 +6,73 @@ namespace StubAPI;
 
 public class ActivityService: IActivityRepository
 {
-    public async Task<IEnumerable<Activity>> GetActivities(int index, int count, ActivityOrderCriteria criteria, bool descending = false)
+    private List<Activity> _activities = new List<Activity>(
+        new Activity[]
         {
-        throw new NotImplementedException();
+            new Activity
+            {
+                Id = 1,
+                    Type = "Running",
+                    Date = new DateTime(2021, 10, 10),
+                    StartTime = new DateTime(2021, 10, 10, 10, 0, 0),
+                    EndTime = new DateTime(2021, 10, 10, 11, 0, 0),
+                    Effort = 3,
+                    Variability = 0.5f,
+                    Variance = 0.5f,
+                    StandardDeviation = 0.5f,
+                    Average = 5.0f,
+                    Maximum = 10,
+                    Minimum = 0,
+                    AverageTemperature = 20.0f,
+                    HasAutoPause = false,
+                    Users = {new User
+                        {
+                            Id = 3, Username = "Athlete3", ProfilePicture = "https://plus.unsplash.com/premium_photo-1705091981693-6006f8a20479?q=80&w=1974&auto=format&fit=crop&ixlib=rb-4.0.3&ixid=M3wxMjA3fDB8MHxwaG90by1wYWdlfHx8fGVufDB8fHx8fA%3D%3D", FirstName = "First3", LastName = "Last3",
+                            Sexe = "M", Lenght = 190, Weight = 80, DateOfBirth = new DateTime(1994, 3, 3), Email = "ath@ex.fr",
+                            Role = new Athlete()
+                        }}
+            },
         }
+    );
     
-    public async Task<Activity?> GetActivityByIdAsync(int id)
+    public async Task<IEnumerable<Activity>?> GetActivities(int index, int count, ActivityOrderCriteria criteria, bool descending = false)
+    => await Task.FromResult(_activities.GetItemsWithFilterAndOrdering(c=>true,index, count,criteria != ActivityOrderCriteria.None ? criteria: null , descending));
+
+    public Task<Activity?> GetActivityByIdAsync(int id)
     {
-        throw new NotImplementedException();
+        return Task.FromResult(_activities.FirstOrDefault(s => s.Id == id));
     }
 
-    public async Task<Activity?> AddActivity(Activity activity)
+    public Task<Activity?> AddActivity(Activity activity)
+    => _activities.AddItem(activity);
+    
+
+    public async Task<Activity?> UpdateActivity(int id, Activity activity)
     {
-        throw new NotImplementedException();
+        var oldActivity = _activities.FirstOrDefault(s => s.Id == id);
+        if (oldActivity == null) return null;
+        return await _activities.UpdateItem(oldActivity, activity);
     }
 
-    public async Task<Activity?> UpdateActivity(int id, Activity activity)
+    public Task<bool> DeleteActivity(int id)
     {
-        throw new NotImplementedException();
+        var activity = _activities.FirstOrDefault(s => s.Id == id);
+        if (activity == null) return Task.FromResult(false);
+        return _activities.DeleteItem(activity);
     }
 
-    public async Task<bool> DeleteActivity(int id)
+    public Task<int> GetNbItems()
+    => Task.FromResult(_activities.Count);
+
+    public async Task<IEnumerable<Activity>?> GetActivitiesByUser(int userId, int index, int count, ActivityOrderCriteria criteria, bool descending = false)
     {
-        throw new NotImplementedException();
+        var activities = _activities.GetItemsWithFilterAndOrdering(c => c.Users.Any(u => u.Id == userId), index, count,
+            criteria != ActivityOrderCriteria.None ? criteria : null, descending);
+        return await Task.FromResult(activities);
     }
 
-    public async Task<int> GetNbItems()
+    public Task<int> GetNbActivitiesByUser(int userId)
     {
-        throw new NotImplementedException();
+        return Task.FromResult(_activities.Count(a => a.Users.Any(u => u.Id == userId)));
     }
 }

src/StubAPI/AthleteService.cs

@@ -51,14 +51,36 @@ public class UserService : IUserRepository
         return true; 
     }
 
-    public async Task<IEnumerable<User>> GetItems(int index, int count, string? orderingProperty = null,
-        bool descending = false)
+    public async Task<bool> RemoveFriend(User user, User friend)
+    {
+        if (user == null || friend == null)
+        {
+            return false;
+        }
+
+        if (!user.Users.Contains(friend))
         {
+            return false;
+        }
         
-        return await this.GetUsers(index, count, this.ToEnum(orderingProperty), descending);
+        user.Users.Remove(friend);
         
+        return true;
+    }
+
+    public async Task<IEnumerable<User>?>? GetFriends(User user, int index, int count, AthleteOrderCriteria? criteria, bool descending = false)
+        =>await Task.FromResult(athletes.FirstOrDefault(s => s.Id == user.Id)?.Users.GetItemsWithFilterAndOrdering(c=>true,index, count,criteria, descending));
+
+    public Task<int> GetNbFriends(User user)
+    {
+        return Task.FromResult(athletes.FirstOrDefault(s => s.Id == user.Id)?.Users.Count ?? 0);
     }
 
+    public async Task<IEnumerable<User>> GetItems(int index, int count, string? orderingProperty = null,
+        bool descending = false)
+    =>await GetUsers(index, count, this.ToEnum(orderingProperty), descending);
+        
+
     public async Task<User?> GetItemById(int id)
     =>await Task.FromResult(athletes.FirstOrDefault(s => s.Id == id));
 

src/StubAPI/Extensions.cs

@@ -39,13 +39,15 @@ public static class Extensions
     
     public static IEnumerable<T> GetItemsWithFilterAndOrdering<T>(this IEnumerable<T> list, Func<T, bool> filter, int index, int count, Enum? orderCriterium, bool descending = false ) where T : class
     {
-        var filteredList = list.Where(filter);
+        IEnumerable<T> query = list;
+
+       query = query.Where(filter);
         
         if(orderCriterium != null)
         {
-            filteredList = filteredList.OrderByCriteria(orderCriterium, descending);
+            query = query.OrderByCriteria(orderCriterium, descending);
         }        
-        return filteredList
+        return query
             .Skip(index * count)
             .Take(count);
     }