Add the ability to add/remove friends in UserProfileHeader

osu.Game.Tests/Visual/Gameplay/TestSceneGameplayLeaderboard.cs

@@ -155,7 +155,7 @@ public void TestFriendScore()
                 var api = (DummyAPIAccess)API;
 
                 api.Friends.Clear();
-                api.Friends.Add(friend);
+                api.Friends.Add(CreateAPIRelationFromAPIUser(friend));
             });
 
             int playerNumber = 1;

osu.Game.Tests/Visual/Online/TestSceneDashboardOverlay.cs

@@ -30,15 +30,15 @@ private void load()
                 if (supportLevel > 3)
                     supportLevel = 0;
 
-                ((DummyAPIAccess)API).Friends.Add(new APIUser
+                ((DummyAPIAccess)API).Friends.Add(CreateAPIRelationFromAPIUser(new APIUser
                 {
                     Username = @"peppy",
                     Id = 2,
                     Colour = "99EB47",
                     CoverUrl = @"https://osu.ppy.sh/images/headers/profile-covers/c3.jpg",
                     IsSupporter = supportLevel > 0,
                     SupportLevel = supportLevel
-                });
+                }));
             }
         }
 

osu.Game.Tests/Visual/Online/TestSceneUserProfileHeader.cs

@@ -3,15 +3,20 @@
 
 using System;
 using System.Linq;
+using System.Threading;
+using System.Threading.Tasks;
 using NUnit.Framework;
 using osu.Framework.Allocation;
 using osu.Framework.Graphics;
 using osu.Framework.Testing;
 using osu.Game.Configuration;
 using osu.Game.Graphics.Containers;
+using osu.Game.Online.API;
+using osu.Game.Online.API.Requests;
 using osu.Game.Online.API.Requests.Responses;
 using osu.Game.Overlays;
 using osu.Game.Overlays.Profile;
+using osu.Game.Overlays.Profile.Header.Components;
 using osu.Game.Rulesets.Osu;
 using osu.Game.Users;
 
@@ -22,6 +27,10 @@ public partial class TestSceneUserProfileHeader : OsuTestScene
         [Cached]
         private readonly OverlayColourProvider colourProvider = new OverlayColourProvider(OverlayColourScheme.Green);
 
+        private DummyAPIAccess dummyAPI => (DummyAPIAccess)API;
+
+        private readonly ManualResetEventSlim requestLock = new ManualResetEventSlim();
+
         [Resolved]
         private OsuConfigManager configManager { get; set; } = null!;
 
@@ -400,5 +409,80 @@ public void TestManyTournamentBanners()
                 }
             }, new OsuRuleset().RulesetInfo));
         }
+
+        private APIUser nonFriend => new APIUser
+        {
+            Id = 727,
+            Username = "Whatever",
+        };
+
+        [Test]
+        public void TestAddFriend()
+        {
+            AddStep("Setup request", () =>
+            {
+                requestLock.Reset();
+
+                dummyAPI.HandleRequest = request =>
+                {
+                    if (request is not FriendAddRequest req)
+                        return false;
+
+                    if (req.TargetId != nonFriend.OnlineID)
+                        return false;
+
+                    var apiRelation = CreateAPIRelationFromAPIUser(nonFriend);
+
+                    Task.Run(() =>
+                    {
+                        requestLock.Wait(3000);
+                        dummyAPI.Friends.Add(apiRelation);
+                        req.TriggerSuccess(apiRelation);
+                    });
+
+                    return true;
+                };
+            });
+            AddStep("clear friend list", () => dummyAPI.Friends.Clear());
+            AddStep("Show non-friend user", () => header.User.Value = new UserProfileData(nonFriend, new OsuRuleset().RulesetInfo));
+            AddStep("Click followers button", () => this.ChildrenOfType<FollowersButton>().First().TriggerClick());
+            AddStep("Complete request", () => requestLock.Set());
+            AddUntilStep("Friend added", () => API.Friends.Any(f => f.TargetID == nonFriend.OnlineID));
+        }
+
+        [Test]
+        public void TestAddFriendNonMutual()
+        {
+            AddStep("Setup request", () =>
+            {
+                requestLock.Reset();
+
+                dummyAPI.HandleRequest = request =>
+                {
+                    if (request is not FriendAddRequest req)
+                        return false;
+
+                    if (req.TargetId != nonFriend.OnlineID)
+                        return false;
+
+                    var apiRelation = CreateAPIRelationFromAPIUser(nonFriend);
+                    apiRelation.Mutual = false;
+
+                    Task.Run(() =>
+                    {
+                        requestLock.Wait(3000);
+                        dummyAPI.Friends.Add(apiRelation);
+                        req.TriggerSuccess(apiRelation);
+                    });
+
+                    return true;
+                };
+            });
+            AddStep("clear friend list", () => dummyAPI.Friends.Clear());
+            AddStep("Show non-friend user", () => header.User.Value = new UserProfileData(nonFriend, new OsuRuleset().RulesetInfo));
+            AddStep("Click followers button", () => this.ChildrenOfType<FollowersButton>().First().TriggerClick());
+            AddStep("Complete request", () => requestLock.Set());
+            AddUntilStep("Friend added", () => API.Friends.Any(f => f.TargetID == nonFriend.OnlineID));
+        }
     }
 }

osu.Game/Online/API/APIAccess.cs

@@ -57,7 +57,7 @@ public partial class APIAccess : Component, IAPIProvider
         private string password;
 
         public IBindable<APIUser> LocalUser => localUser;
-        public IBindableList<APIUser> Friends => friends;
+        public IBindableList<APIRelation> Friends => friends;
         public IBindable<UserActivity> Activity => activity;
         public IBindable<UserStatistics> Statistics => statistics;
 
@@ -67,7 +67,7 @@ public partial class APIAccess : Component, IAPIProvider
 
         private Bindable<APIUser> localUser { get; } = new Bindable<APIUser>(createGuestUser());
 
-        private BindableList<APIUser> friends { get; } = new BindableList<APIUser>();
+        private BindableList<APIRelation> friends { get; } = new BindableList<APIRelation>();
 
         private Bindable<UserActivity> activity { get; } = new Bindable<UserActivity>();
 
@@ -360,19 +360,7 @@ private void attemptConnect()
                 }
             }
 
-            var friendsReq = new GetFriendsRequest();
-            friendsReq.Failure += _ => state.Value = APIState.Failing;
-            friendsReq.Success += res =>
-            {
-                friends.Clear();
-                friends.AddRange(res);
-            };
-
-            if (!handleRequest(friendsReq))
-            {
-                state.Value = APIState.Failing;
-                return;
-            }
+            UpdateLocalFriends();
 
             // The Success callback event is fired on the main thread, so we should wait for that to run before proceeding.
             // Without this, we will end up circulating this Connecting loop multiple times and queueing up many web requests
@@ -624,6 +612,22 @@ public void UpdateStatistics(UserStatistics newStatistics)
                 localUser.Value.Statistics = newStatistics;
         }
 
+        public void UpdateLocalFriends()
+        {
+            if (!IsLoggedIn)
+                return;
+
+            var friendsReq = new GetFriendsRequest();
+            friendsReq.Failure += _ => state.Value = APIState.Failing;
+            friendsReq.Success += res =>
+            {
+                friends.Clear();
+                friends.AddRange(res);
+            };
+
+            Queue(friendsReq);
+        }
+
         private static APIUser createGuestUser() => new GuestUser();
 
         private void setLocalUser(APIUser user) => Scheduler.Add(() =>

osu.Game/Online/API/DummyAPIAccess.cs

@@ -26,7 +26,7 @@ public partial class DummyAPIAccess : Component, IAPIProvider
             Id = DUMMY_USER_ID,
         });
 
-        public BindableList<APIUser> Friends { get; } = new BindableList<APIUser>();
+        public BindableList<APIRelation> Friends { get; } = new BindableList<APIRelation>();
 
         public Bindable<UserActivity> Activity { get; } = new Bindable<UserActivity>();
 
@@ -201,6 +201,10 @@ public void UpdateStatistics(UserStatistics newStatistics)
                 LocalUser.Value.Statistics = newStatistics;
         }
 
+        public void UpdateLocalFriends()
+        {
+        }
+
         public IHubClientConnector? GetHubConnector(string clientName, string endpoint, bool preferMessagePack) => null;
 
         public IChatClient GetChatClient() => new TestChatClientConnector(this);
@@ -214,7 +218,7 @@ public void UpdateStatistics(UserStatistics newStatistics)
         public void SetState(APIState newState) => state.Value = newState;
 
         IBindable<APIUser> IAPIProvider.LocalUser => LocalUser;
-        IBindableList<APIUser> IAPIProvider.Friends => Friends;
+        IBindableList<APIRelation> IAPIProvider.Friends => Friends;
         IBindable<UserActivity> IAPIProvider.Activity => Activity;
         IBindable<UserStatistics?> IAPIProvider.Statistics => Statistics;
 

osu.Game/Online/API/IAPIProvider.cs

@@ -22,7 +22,7 @@ public interface IAPIProvider
         /// <summary>
         /// The user's friends.
         /// </summary>
-        IBindableList<APIUser> Friends { get; }
+        IBindableList<APIRelation> Friends { get; }
 
         /// <summary>
         /// The current user's activity.
@@ -134,6 +134,11 @@ public interface IAPIProvider
         /// </summary>
         void UpdateStatistics(UserStatistics newStatistics);
 
+        /// <summary>
+        /// Update the friends status of the current user.
+        /// </summary>
+        void UpdateLocalFriends();
+
         /// <summary>
         /// Schedule a callback to run on the update thread.
         /// </summary>

osu.Game/Online/API/Requests/FriendAddRequest.cs

@@ -0,0 +1,31 @@
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using System.Net.Http;
+using osu.Framework.IO.Network;
+using osu.Game.Online.API.Requests.Responses;
+
+namespace osu.Game.Online.API.Requests
+{
+    public class FriendAddRequest : APIRequest<APIRelation>
+    {
+        public readonly int TargetId;
+
+        public FriendAddRequest(int targetId)
+        {
+            TargetId = targetId;
+        }
+
+        protected override WebRequest CreateWebRequest()
+        {
+            var req = base.CreateWebRequest();
+
+            req.Method = HttpMethod.Post;
+            req.AddParameter("target", TargetId.ToString(), RequestParameterType.Query);
+
+            return req;
+        }
+
+        protected override string Target => @"friends";
+    }
+}

osu.Game/Online/API/Requests/FriendDeleteRequest.cs

@@ -0,0 +1,27 @@
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using System.Net.Http;
+using osu.Framework.IO.Network;
+
+namespace osu.Game.Online.API.Requests
+{
+    public class FriendDeleteRequest : APIRequest
+    {
+        public readonly int TargetId;
+
+        public FriendDeleteRequest(int targetId)
+        {
+            TargetId = targetId;
+        }
+
+        protected override WebRequest CreateWebRequest()
+        {
+            var req = base.CreateWebRequest();
+            req.Method = HttpMethod.Delete;
+            return req;
+        }
+
+        protected override string Target => $@"friends/{TargetId}";
+    }
+}

osu.Game/Online/API/Requests/GetFriendsRequest.cs

@@ -6,7 +6,7 @@
 
 namespace osu.Game.Online.API.Requests
 {
-    public class GetFriendsRequest : APIRequest<List<APIUser>>
+    public class GetFriendsRequest : APIRequest<List<APIRelation>>
     {
         protected override string Target => @"friends";
     }

osu.Game/Online/API/Requests/Responses/APIRelation.cs

@@ -0,0 +1,28 @@
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using Newtonsoft.Json;
+
+namespace osu.Game.Online.API.Requests.Responses
+{
+    public class APIRelation
+    {
+        [JsonProperty("target_id")]
+        public int TargetID { get; set; }
+
+        [JsonProperty("relation_type")]
+        public RelationType RelationType { get; set; }
+
+        [JsonProperty("mutual")]
+        public bool Mutual { get; set; }
+
+        [JsonProperty("target")]
+        public APIUser? TargetUser { get; set; }
+    }
+
+    public enum RelationType
+    {
+        Friend,
+        Block,
+    }
+}

osu.Game/Overlays/Dashboard/Friends/FriendDisplay.cs

@@ -44,7 +44,7 @@ public List<APIUser> Users
         private Container itemsPlaceholder;
         private LoadingLayer loading;
 
-        private readonly IBindableList<APIUser> apiFriends = new BindableList<APIUser>();
+        private readonly IBindableList<APIRelation> apiFriends = new BindableList<APIRelation>();
 
         public FriendDisplay()
         {
@@ -145,7 +145,7 @@ private void load(OverlayColourProvider colourProvider, IAPIProvider api)
             controlBackground.Colour = colourProvider.Background5;
 
             apiFriends.BindTo(api.Friends);
-            apiFriends.BindCollectionChanged((_, _) => Schedule(() => Users = apiFriends.ToList()), true);
+            apiFriends.BindCollectionChanged((_, _) => Schedule(() => Users = apiFriends.Select(f => f.TargetUser).ToList()), true);
         }
 
         protected override void LoadComplete()