fix(commands): Fix handling of pulling context

Remora.Discord.Commands/Extensions/ServiceCollectionExtensions.cs

@@ -237,6 +237,7 @@ public static IServiceCollection AddDiscordCommands
             .AddParser<EmojiParser>()
             .AddParser<GuildMemberParser>()
             .AddParser<MessageParser>()
+            .AddParser<PartialMessageParser>()
             .AddParser<RoleParser>()
             .AddParser<UserParser>();
 

Remora.Discord.Commands/Parsers/MessageParser.cs

@@ -38,10 +38,10 @@
 namespace Remora.Discord.Commands.Parsers;
 
 /// <summary>
-/// Parses instances of <see cref="IMessage"/> and <see cref="IPartialMessage"/> from command-line inputs.
+/// Parses instances of <see cref="IMessage"/> from command-line inputs.
 /// </summary>
 [PublicAPI]
-public class MessageParser : AbstractTypeParser<IMessage>, ITypeParser<IPartialMessage>
+public class MessageParser : AbstractTypeParser<IMessage>
 {
     private static readonly Regex _messageLinkRegex = new
     (
@@ -100,65 +100,4 @@ public override async ValueTask<Result<IMessage>> TryParseAsync
 
         return await _channelAPI.GetChannelMessageAsync(channelId.Value, messageId.Value, ct);
     }
-
-    /// <inheritdoc/>
-    async ValueTask<Result<IPartialMessage>> ITypeParser<IPartialMessage>.TryParseAsync
-    (
-        IReadOnlyList<string> tokens,
-        CancellationToken ct
-    )
-    {
-        return (await (this as ITypeParser<IMessage>).TryParseAsync(tokens, ct)).Map(a => a as IPartialMessage);
-    }
-
-    /// <inheritdoc/>
-    async ValueTask<Result<IPartialMessage>> ITypeParser<IPartialMessage>.TryParseAsync
-    (
-        string token,
-        CancellationToken ct
-    )
-    {
-        _ = DiscordSnowflake.TryParse(token.Unmention(), out var messageID);
-        if (messageID is null)
-        {
-            var messageLinkMatch = _messageLinkRegex.Match(token);
-            if (!messageLinkMatch.Success)
-            {
-                return new ParsingError<IPartialMessage>(token, "Unrecognized input format.");
-            }
-
-            var messageIdRaw = messageLinkMatch.Groups["message_id"].Value;
-            if (!DiscordSnowflake.TryParse(messageIdRaw, out messageID))
-            {
-                return new ParsingError<IPartialMessage>(token, "Unrecognized input format.");
-            }
-        }
-
-        var resolvedMessage = GetResolvedMessageOrDefault(messageID.Value);
-        return resolvedMessage is null
-            ? (await (this as ITypeParser<IMessage>).TryParseAsync(token, ct)).Map(a => a as IPartialMessage)
-            : Result<IPartialMessage>.FromSuccess(resolvedMessage);
-    }
-
-    private IPartialMessage? GetResolvedMessageOrDefault(Snowflake messageID)
-    {
-        if (_context is not IInteractionContext interactionContext)
-        {
-            return null;
-        }
-
-        if (!interactionContext.Interaction.Data.TryGet(out var data))
-        {
-            return null;
-        }
-
-        var resolvedData = data.Match(a => a.Resolved, _ => default, _ => default);
-        if (!resolvedData.TryGet(out var resolved) || !resolved.Messages.TryGet(out var messages))
-        {
-            return null;
-        }
-
-        _ = messages.TryGetValue(messageID, out var message);
-        return message;
-    }
 }

Remora.Discord.Commands/Parsers/PartialMessageParser.cs

@@ -0,0 +1,92 @@
+//
+//  PartialMessageParser.cs
+//
+//  Author:
+//       Jarl Gullberg <[email protected]>
+//
+//  Copyright (c) Jarl Gullberg
+//
+//  This program is free software: you can redistribute it and/or modify
+//  it under the terms of the GNU Lesser General Public License as published by
+//  the Free Software Foundation, either version 3 of the License, or
+//  (at your option) any later version.
+//
+//  This program is distributed in the hope that it will be useful,
+//  but WITHOUT ANY WARRANTY; without even the implied warranty of
+//  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+//  GNU Lesser General Public License for more details.
+//
+//  You should have received a copy of the GNU Lesser General Public License
+//  along with this program.  If not, see <http://www.gnu.org/licenses/>.
+//
+
+using System.Threading;
+using System.Threading.Tasks;
+using JetBrains.Annotations;
+using Remora.Commands.Parsers;
+using Remora.Discord.API;
+using Remora.Discord.API.Abstractions.Objects;
+using Remora.Discord.Commands.Contexts;
+using Remora.Discord.Commands.Extensions;
+using Remora.Results;
+
+namespace Remora.Discord.Commands.Parsers;
+
+/// <summary>
+/// Parses instances of <see cref="IPartialMessage"/> from command-line inputs.
+/// </summary>
+[PublicAPI]
+public class PartialMessageParser : AbstractTypeParser<IPartialMessage>
+{
+    private readonly IInteractionContext? _context;
+    private readonly ITypeParser<IMessage> _messageParser;
+
+    /// <summary>
+    /// Initializes a new instance of the <see cref="PartialMessageParser"/> class.
+    /// </summary>
+    /// <param name="context">The interaction context, if available. </param>
+    /// <param name="messageParser">The message parser to delegate to, if necessary.</param>
+    public PartialMessageParser(IInteractionContext? context, ITypeParser<IMessage> messageParser)
+    {
+        _context = context;
+        _messageParser = messageParser;
+    }
+
+    /// <inheritdoc />
+    public override async ValueTask<Result<IPartialMessage>> TryParseAsync
+    (
+        string value,
+        CancellationToken ct = default
+    )
+    {
+        var resolvedValue = ResolveMessageFromContext(value);
+
+        return resolvedValue is not null ? Result<IPartialMessage>.FromSuccess(resolvedValue) : (await _messageParser.TryParseAsync(value, ct)).Map<IPartialMessage>(m => m);
+    }
+
+    private IPartialMessage? ResolveMessageFromContext(string value)
+    {
+        if (_context is null)
+        {
+            return null;
+        }
+
+        if (!DiscordSnowflake.TryParse(value.Unmention(), out var messageID))
+        {
+            return null;
+        }
+
+        if (!_context.Interaction.Data.TryGet(out var interactionData) || interactionData.TryPickT0(out var strongData, out _))
+        {
+            return null;
+        }
+
+        if (!strongData.Resolved.TryGet(out var resolved) || !resolved.Messages.TryGet(out var messages))
+        {
+            return null;
+        }
+
+        _ = messages.TryGetValue(messageID.Value, out var message);
+        return message;
+    }
+}