refactor: move ContextExts to own folder, CommandTree / command defs to CommandMeta folder

PluralKit.Bot/CommandSystem/Context/Context.cs

@@ -0,0 +1,140 @@
+using System;
+using System.Threading.Tasks;
+
+using App.Metrics;
+
+using Autofac;
+
+using Myriad.Cache;
+using Myriad.Extensions;
+using Myriad.Gateway;
+using Myriad.Rest;
+using Myriad.Rest.Types;
+using Myriad.Rest.Types.Requests;
+using Myriad.Types;
+
+using PluralKit.Core;
+
+namespace PluralKit.Bot;
+
+public class Context
+{
+    private readonly ILifetimeScope _provider;
+
+    private readonly Parameters _parameters;
+
+    private readonly IMetrics _metrics;
+    private readonly CommandMessageService _commandMessageService;
+
+    private Command? _currentCommand;
+
+    public Context(ILifetimeScope provider, Shard shard, Guild? guild, Channel channel, MessageCreateEvent message, int commandParseOffset,
+                    PKSystem senderSystem, MessageContext messageContext)
+    {
+        Message = (Message)message;
+        Shard = shard;
+        Guild = guild;
+        Channel = channel;
+        System = senderSystem;
+        MessageContext = messageContext;
+        Cache = provider.Resolve<IDiscordCache>();
+        Database = provider.Resolve<IDatabase>();
+        Repository = provider.Resolve<ModelRepository>();
+        _metrics = provider.Resolve<IMetrics>();
+        _provider = provider;
+        _commandMessageService = provider.Resolve<CommandMessageService>();
+        _parameters = new Parameters(message.Content?.Substring(commandParseOffset));
+        Rest = provider.Resolve<DiscordApiClient>();
+        Cluster = provider.Resolve<Cluster>();
+    }
+
+    public readonly IDiscordCache Cache;
+    public readonly DiscordApiClient Rest;
+
+    public readonly Channel Channel;
+    public User Author => Message.Author;
+    public GuildMemberPartial Member => ((MessageCreateEvent)Message).Member;
+
+    public readonly Message Message;
+    public readonly Guild Guild;
+    public readonly Shard Shard;
+    public readonly Cluster Cluster;
+    public readonly MessageContext MessageContext;
+
+    public Task<PermissionSet> BotPermissions => Cache.PermissionsIn(Channel.Id);
+    public Task<PermissionSet> UserPermissions => Cache.PermissionsFor((MessageCreateEvent)Message);
+
+
+    public readonly PKSystem System;
+
+    public readonly Parameters Parameters;
+
+    internal readonly IDatabase Database;
+    internal readonly ModelRepository Repository;
+
+    public async Task<Message> Reply(string text = null, Embed embed = null, AllowedMentions? mentions = null)
+    {
+        var botPerms = await BotPermissions;
+
+        if (!botPerms.HasFlag(PermissionSet.SendMessages))
+            // Will be "swallowed" during the error handler anyway, this message is never shown.
+            throw new PKError("PluralKit does not have permission to send messages in this channel.");
+
+        if (embed != null && !botPerms.HasFlag(PermissionSet.EmbedLinks))
+            throw new PKError("PluralKit does not have permission to send embeds in this channel. Please ensure I have the **Embed Links** permission enabled.");
+
+        var msg = await Rest.CreateMessage(Channel.Id, new MessageRequest
+        {
+            Content = text,
+            Embed = embed,
+            // Default to an empty allowed mentions object instead of null (which means no mentions allowed)
+            AllowedMentions = mentions ?? new AllowedMentions()
+        });
+
+        if (embed != null)
+        {
+            // Sensitive information that might want to be deleted by :x: reaction is typically in an embed format (member cards, for example)
+            // This may need to be changed at some point but works well enough for now
+            await _commandMessageService.RegisterMessage(msg.Id, msg.ChannelId, Author.Id);
+        }
+
+        return msg;
+    }
+
+    public async Task Execute<T>(Command? commandDef, Func<T, Task> handler)
+    {
+        _currentCommand = commandDef;
+
+        try
+        {
+            using (_metrics.Measure.Timer.Time(BotMetrics.CommandTime, new MetricTags("Command", commandDef?.Key ?? "null")))
+                await handler(_provider.Resolve<T>());
+
+            _metrics.Measure.Meter.Mark(BotMetrics.CommandsRun);
+        }
+        catch (PKSyntaxError e)
+        {
+            await Reply($"{Emojis.Error} {e.Message}\n**Command usage:**\n> pk;{commandDef?.Usage}");
+        }
+        catch (PKError e)
+        {
+            await Reply($"{Emojis.Error} {e.Message}");
+        }
+        catch (TimeoutException)
+        {
+            // Got a complaint the old error was a bit too patronizing. Hopefully this is better?
+            await Reply($"{Emojis.Error} Operation timed out, sorry. Try again, perhaps?");
+        }
+    }
+
+    public LookupContext LookupContextFor(PKSystem target) =>
+        System?.Id == target.Id ? LookupContext.ByOwner : LookupContext.ByNonOwner;
+
+    public LookupContext LookupContextFor(SystemId systemId) =>
+        System?.Id == systemId ? LookupContext.ByOwner : LookupContext.ByNonOwner;
+
+    public LookupContext LookupContextFor(PKMember target) =>
+        System?.Id == target.System ? LookupContext.ByOwner : LookupContext.ByNonOwner;
+
+    public IComponentContext Services => _provider;
+}