Implemented application emojis.

src/Disqord.Core/Entities/Core/Emoji/IApplicationEmoji.cs

@@ -0,0 +1,24 @@
+using Disqord.Models;
+
+namespace Disqord;
+
+/// <summary>
+///     Represents a custom emoji (e.g. <c>&lt;:professor:667582610431803437&gt;</c>) retrieved from an application.
+/// </summary>
+public interface IApplicationEmoji : ICustomEmoji, IApplicationEntity, IClientEntity, INamableEntity, IJsonUpdatable<EmojiJsonModel>
+{
+    /// <summary>
+    ///     Gets the user that created this emoji.
+    /// </summary>
+    IUser? Creator { get; }
+
+    /// <summary>
+    ///     Gets whether this emoji requires colons in chat.
+    /// </summary>
+    bool RequiresColons { get; }
+
+    /// <summary>
+    ///     Gets whether this emoji is managed by an integration.
+    /// </summary>
+    bool IsManaged { get; }
+}

src/Disqord.Core/Entities/Core/IApplicationEntity.cs

@@ -0,0 +1,12 @@
+namespace Disqord;
+
+/// <summary>
+///     Represents a Discord entity that exists within an application.
+/// </summary>
+public interface IApplicationEntity
+{
+    /// <summary>
+    ///     Gets the ID of the application this entity is tied to.
+    /// </summary>
+    Snowflake ApplicationId { get; }
+}

src/Disqord.Core/Entities/Transient/Emoji/TransientApplicationEmoji.cs

@@ -0,0 +1,59 @@
+using Disqord.Models;
+using Qommon;
+
+namespace Disqord;
+
+public class TransientApplicationEmoji : TransientClientEntity<EmojiJsonModel>, IApplicationEmoji
+{
+    /// <inheritdoc />
+    public Snowflake Id => Model.Id!.Value;
+
+    /// <inheritdoc />
+    public Snowflake ApplicationId { get; }
+
+    /// <inheritdoc cref="INamableEntity.Name"/>
+    public string Name => Model.Name!;
+
+    /// <inheritdoc/>
+    public bool IsAnimated => Model.Animated.Value;
+
+    /// <inheritdoc/>
+    public IUser? Creator => _creator ??= Optional.ConvertOrDefault(Model.User, static (user, client) => new TransientUser(client, user), Client);
+
+    private IUser? _creator;
+
+    /// <inheritdoc/>
+    public bool RequiresColons => Model.RequireColons.Value;
+
+    /// <inheritdoc/>
+    public bool IsManaged => Model.Managed.Value;
+
+    /// <inheritdoc/>
+    public string Tag => ToString();
+
+    public TransientApplicationEmoji(IClient client, Snowflake applicationId, EmojiJsonModel model)
+        : base(client, model)
+    {
+        ApplicationId = applicationId;
+    }
+
+    public bool Equals(IEmoji? other)
+    {
+        return Comparers.Emoji.Equals(this, other);
+    }
+
+    public bool Equals(ICustomEmoji? other)
+    {
+        return Comparers.Emoji.Equals(this, other);
+    }
+
+    public override int GetHashCode()
+    {
+        return Comparers.Emoji.GetHashCode(this);
+    }
+
+    public override string ToString()
+    {
+        return this.GetString();
+    }
+}

src/Disqord.Rest.Api/Content/Json/CreateApplicationEmojiJsonRestRequestContent.cs

@@ -0,0 +1,19 @@
+using System.IO;
+using Disqord.Serialization.Json;
+
+namespace Disqord.Rest.Api;
+
+public class CreateApplicationEmojiJsonRestRequestContent : JsonModelRestRequestContent
+{
+    [JsonProperty("name")]
+    public string Name;
+
+    [JsonProperty("image")]
+    public Stream Image;
+
+    public CreateApplicationEmojiJsonRestRequestContent(string name, Stream image)
+    {
+        Name = name;
+        Image = image;
+    }
+}

src/Disqord.Rest.Api/Content/Json/ModifyApplicationEmojiJsonRestRequestContent.cs

@@ -0,0 +1,10 @@
+using Disqord.Serialization.Json;
+using Qommon;
+
+namespace Disqord.Rest.Api;
+
+public class ModifyApplicationEmojiJsonRestRequestContent : JsonModelRestRequestContent
+{
+    [JsonProperty("name")]
+    public Optional<string> Name;
+}

src/Disqord.Rest.Api/Methods/RestApiClientExtensions.Emoji.cs

@@ -6,6 +6,46 @@ namespace Disqord.Rest.Api;
 
 public static partial class RestApiClientExtensions
 {
+    public static Task<EmojiJsonModel[]> FetchApplicationEmojisAsync(this IRestApiClient client,
+        Snowflake applicationId,
+        IRestRequestOptions? options = null, CancellationToken cancellationToken = default)
+    {
+        var route = Format(Route.Emoji.GetApplicationEmojis, applicationId);
+        return client.ExecuteAsync<EmojiJsonModel[]>(route, null, options, cancellationToken);
+    }
+
+    public static Task<EmojiJsonModel> FetchApplicationEmojiAsync(this IRestApiClient client,
+        Snowflake applicationId, Snowflake emojiId,
+        IRestRequestOptions? options = null, CancellationToken cancellationToken = default)
+    {
+        var route = Format(Route.Emoji.GetApplicationEmoji, applicationId, emojiId);
+        return client.ExecuteAsync<EmojiJsonModel>(route, null, options, cancellationToken);
+    }
+
+    public static Task<EmojiJsonModel> CreateApplicationEmojiAsync(this IRestApiClient client,
+        Snowflake applicationId, CreateApplicationEmojiJsonRestRequestContent content,
+        IRestRequestOptions? options = null, CancellationToken cancellationToken = default)
+    {
+        var route = Format(Route.Emoji.CreateApplicationEmoji, applicationId);
+        return client.ExecuteAsync<EmojiJsonModel>(route, content, options, cancellationToken);
+    }
+
+    public static Task<EmojiJsonModel> ModifyApplicationEmojiAsync(this IRestApiClient client,
+        Snowflake applicationId, Snowflake emojiId, ModifyApplicationEmojiJsonRestRequestContent content,
+        IRestRequestOptions? options = null, CancellationToken cancellationToken = default)
+    {
+        var route = Format(Route.Emoji.ModifyApplicationEmoji, applicationId, emojiId);
+        return client.ExecuteAsync<EmojiJsonModel>(route, content, options, cancellationToken);
+    }
+
+    public static Task DeleteApplicationEmojiAsync(this IRestApiClient client,
+        Snowflake applicationId, Snowflake emojiId,
+        IRestRequestOptions? options = null, CancellationToken cancellationToken = default)
+    {
+        var route = Format(Route.Emoji.DeleteApplicationEmoji, applicationId, emojiId);
+        return client.ExecuteAsync<EmojiJsonModel>(route, null, options, cancellationToken);
+    }
+
     public static Task<EmojiJsonModel[]> FetchGuildEmojisAsync(this IRestApiClient client,
         Snowflake guildId,
         IRestRequestOptions? options = null, CancellationToken cancellationToken = default)

src/Disqord.Rest.Api/Requests/Routing/Default/Route.Static.cs

@@ -112,6 +112,16 @@ public static class Channel
 
     public static class Emoji
     {
+        public static readonly Route GetApplicationEmojis = Get("applications/{0:application_id}/emojis");
+
+        public static readonly Route GetApplicationEmoji = Get("applications/{0:application_id}/emojis/{1:emoji_id}");
+
+        public static readonly Route CreateApplicationEmoji = Post("applications/{0:application_id}/emojis");
+
+        public static readonly Route ModifyApplicationEmoji = Patch("applications/{0:application_id}/emojis/{1:emoji_id}");
+
+        public static readonly Route DeleteApplicationEmoji = Delete("applications/{0:application_id}/emojis/{1:emoji_id}");
+
         public static readonly Route GetGuildEmojis = Get("guilds/{0:guild_id}/emojis");
 
         public static readonly Route GetGuildEmoji = Get("guilds/{0:guild_id}/emojis/{1:emoji_id}");

src/Disqord.Rest/ActionProperties/Modify/ModifyApplicationEmojiActionProperties.cs

@@ -0,0 +1,11 @@
+using Qommon;
+
+namespace Disqord;
+
+public class ModifyApplicationEmojiActionProperties
+{
+    public Optional<string> Name { internal get; set; }
+
+    internal ModifyApplicationEmojiActionProperties()
+    { }
+}

src/Disqord.Rest/Extensions/Entity/RestEntityExtensions.Application.cs

@@ -0,0 +1,49 @@
+using System;
+using System.Collections.Generic;
+using System.IO;
+using System.Threading;
+using System.Threading.Tasks;
+
+namespace Disqord.Rest;
+
+public static partial class RestEntityExtensions
+{
+    public static Task<IReadOnlyList<IApplicationEmoji>> FetchEmojisAsync(this IApplication application,
+        IRestRequestOptions? options = null, CancellationToken cancellationToken = default)
+    {
+        var client = application.GetRestClient();
+        return client.FetchApplicationEmojisAsync(application.Id, options, cancellationToken);
+    }
+
+    public static Task<IApplicationEmoji> FetchEmojiAsync(this IApplication application,
+        Snowflake emojiId,
+        IRestRequestOptions? options = null, CancellationToken cancellationToken = default)
+    {
+        var client = application.GetRestClient();
+        return client.FetchApplicationEmojiAsync(application.Id, emojiId, options, cancellationToken);
+    }
+
+    public static Task<IApplicationEmoji> CreateEmojiAsync(this IApplication application,
+        string name, Stream image,
+        IRestRequestOptions? options = null, CancellationToken cancellationToken = default)
+    {
+        var client = application.GetRestClient();
+        return client.CreateApplicationEmojiAsync(application.Id, name, image, options, cancellationToken);
+    }
+
+    public static Task<IApplicationEmoji> ModifyEmojiAsync(this IApplication application,
+        Snowflake emojiId, Action<ModifyApplicationEmojiActionProperties> action,
+        IRestRequestOptions? options = null, CancellationToken cancellationToken = default)
+    {
+        var client = application.GetRestClient();
+        return client.ModifyApplicationEmojiAsync(application.Id, emojiId, action, options, cancellationToken);
+    }
+
+    public static Task DeleteEmojiAsync(this IApplication application,
+        Snowflake emojiId,
+        IRestRequestOptions? options = null, CancellationToken cancellationToken = default)
+    {
+        var client = application.GetRestClient();
+        return client.DeleteApplicationEmojiAsync(application.Id, emojiId, options, cancellationToken);
+    }
+}

src/Disqord.Rest/Extensions/Entity/RestEntityExtensions.Emoji.cs

@@ -6,6 +6,21 @@ namespace Disqord.Rest;
 
 public static partial class RestEntityExtensions
 {
+    public static Task<IApplicationEmoji> ModifyAsync(this IApplicationEmoji emoji,
+        Action<ModifyApplicationEmojiActionProperties> action,
+        IRestRequestOptions? options = null, CancellationToken cancellationToken = default)
+    {
+        var client = emoji.GetRestClient();
+        return client.ModifyApplicationEmojiAsync(emoji.ApplicationId, emoji.Id, action, options, cancellationToken);
+    }
+
+    public static Task DeleteAsync(this IApplicationEmoji emoji,
+        IRestRequestOptions? options = null, CancellationToken cancellationToken = default)
+    {
+        var client = emoji.GetRestClient();
+        return client.DeleteApplicationEmojiAsync(emoji.ApplicationId, emoji.Id, options, cancellationToken);
+    }
+
     public static Task<IGuildEmoji> ModifyAsync(this IGuildEmoji emoji,
         Action<ModifyGuildEmojiActionProperties> action,
         IRestRequestOptions? options = null, CancellationToken cancellationToken = default)

src/Disqord.Rest/Extensions/Entity/RestEntityExtensions.User.cs

@@ -1,4 +1,5 @@
 using System;
+using System.Collections.Generic;
 using System.Threading;
 using System.Threading.Tasks;
 

src/Disqord.Rest/Extensions/RestClientExtensions.Emoji.cs

@@ -12,6 +12,60 @@ namespace Disqord.Rest;
 
 public static partial class RestClientExtensions
 {
+    public static async Task<IReadOnlyList<IApplicationEmoji>> FetchApplicationEmojisAsync(this IRestClient client,
+        Snowflake applicationId,
+        IRestRequestOptions? options = null, CancellationToken cancellationToken = default)
+    {
+        var models = await client.ApiClient.FetchApplicationEmojisAsync(applicationId, options, cancellationToken).ConfigureAwait(false);
+        return models.ToReadOnlyList((client, applicationId), static (model, state) =>
+        {
+            var (client, applicationId) = state;
+            return new TransientApplicationEmoji(client, applicationId, model);
+        });
+    }
+
+    public static async Task<IApplicationEmoji> FetchApplicationEmojiAsync(this IRestClient client,
+        Snowflake applicationId, Snowflake emojiId,
+        IRestRequestOptions? options = null, CancellationToken cancellationToken = default)
+    {
+        var model = await client.ApiClient.FetchApplicationEmojiAsync(applicationId, emojiId, options, cancellationToken).ConfigureAwait(false);
+        return new TransientApplicationEmoji(client, applicationId, model);
+    }
+
+    public static async Task<IApplicationEmoji> CreateApplicationEmojiAsync(this IRestClient client,
+        Snowflake applicationId, string name, Stream image,
+        IRestRequestOptions? options = null, CancellationToken cancellationToken = default)
+    {
+        var content = new CreateApplicationEmojiJsonRestRequestContent(name, image);
+
+        var model = await client.ApiClient.CreateApplicationEmojiAsync(applicationId, content, options, cancellationToken).ConfigureAwait(false);
+        return new TransientApplicationEmoji(client, applicationId, model);
+    }
+
+    public static async Task<IApplicationEmoji> ModifyApplicationEmojiAsync(this IRestClient client,
+        Snowflake applicationId, Snowflake emojiId, Action<ModifyApplicationEmojiActionProperties> action,
+        IRestRequestOptions? options = null, CancellationToken cancellationToken = default)
+    {
+        Guard.IsNotNull(action);
+
+        var properties = new ModifyApplicationEmojiActionProperties();
+        action.Invoke(properties);
+        var content = new ModifyApplicationEmojiJsonRestRequestContent()
+        {
+            Name = properties.Name
+        };
+
+        var model = await client.ApiClient.ModifyApplicationEmojiAsync(applicationId, emojiId, content, options, cancellationToken).ConfigureAwait(false);
+        return new TransientApplicationEmoji(client, applicationId, model);
+    }
+
+    public static Task DeleteApplicationEmojiAsync(this IRestClient client,
+        Snowflake applicationId, Snowflake emojiId,
+        IRestRequestOptions? options = null, CancellationToken cancellationToken = default)
+    {
+        return client.ApiClient.DeleteApplicationEmojiAsync(applicationId, emojiId, options, cancellationToken);
+    }
+
     public static async Task<IReadOnlyList<IGuildEmoji>> FetchGuildEmojisAsync(this IRestClient client,
         Snowflake guildId,
         IRestRequestOptions? options = null, CancellationToken cancellationToken = default)