Add switch commands for adding and moving

PluralKit.Bot/Bot.cs

@@ -1,5 +1,6 @@
 using System;
 using System.Data;
+using System.Diagnostics;
 using System.Linq;
 using System.Reflection;
 using System.Threading;
@@ -34,8 +35,6 @@ namespace PluralKit.Bot
             {
                 Console.WriteLine("- Connecting to database...");
                 var connection = services.GetRequiredService<IDbConnection>() as NpgsqlConnection;
-                connection.ConnectionString = services.GetRequiredService<CoreConfig>().Database;
-                await connection.OpenAsync();
                 await Schema.CreateTables(connection);
 
                 Console.WriteLine("- Connecting to Discord...");
@@ -54,7 +53,13 @@ namespace PluralKit.Bot
                 .AddTransient(_ => _config.GetSection("PluralKit").Get<CoreConfig>() ?? new CoreConfig())
                 .AddTransient(_ => _config.GetSection("PluralKit").GetSection("Bot").Get<BotConfig>() ?? new BotConfig())
                 
-                .AddScoped<IDbConnection>(svc => new NpgsqlConnection(svc.GetRequiredService<CoreConfig>().Database))
+                .AddScoped<IDbConnection>(svc =>
+                {
+                    
+                    var conn = new NpgsqlConnection(svc.GetRequiredService<CoreConfig>().Database);
+                    conn.Open();
+                    return conn;
+                })
                 
                 .AddSingleton<IDiscordClient, DiscordSocketClient>()
                 .AddSingleton<Bot>()
@@ -68,6 +73,7 @@ namespace PluralKit.Bot
                 .AddTransient<SystemStore>()
                 .AddTransient<MemberStore>()
                 .AddTransient<MessageStore>()
+                .AddTransient<SwitchStore>()
                 .BuildServiceProvider();
     }
     class Bot
@@ -138,7 +144,7 @@ namespace PluralKit.Bot
                     }
                 } else if ((_result.Error == CommandError.BadArgCount || _result.Error == CommandError.MultipleMatches) && cmd.IsSpecified) {
                     await ctx.Message.Channel.SendMessageAsync($"{Emojis.Error} {_result.ErrorReason}\n**Usage: **pk;{cmd.Value.Remarks}");
-                } else if (_result.Error == CommandError.UnknownCommand || _result.Error == CommandError.UnmetPrecondition) {
+                } else if (_result.Error == CommandError.UnknownCommand || _result.Error == CommandError.UnmetPrecondition || _result.Error == CommandError.ObjectNotFound) {
                     await ctx.Message.Channel.SendMessageAsync($"{Emojis.Error} {_result.ErrorReason}");
                 }
             }

PluralKit.Bot/Commands/SwitchCommands.cs

@@ -0,0 +1,92 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Threading.Tasks;
+using Discord;
+using Discord.Commands;
+using NodaTime;
+using NodaTime.TimeZones;
+
+namespace PluralKit.Bot.Commands
+{
+    [Group("switch")]
+    public class SwitchCommands: ModuleBase<PKCommandContext>
+    {
+        public SystemStore Systems { get; set; }
+        public SwitchStore Switches { get; set; }
+
+        [Command]
+        [Remarks("switch <member> [member...]")]
+        [MustHaveSystem]
+        public async Task Switch(params PKMember[] members) => await DoSwitchCommand(members);
+
+        [Command("out")]
+        [MustHaveSystem]
+        public async Task SwitchOut() => await DoSwitchCommand(new PKMember[] { });
+
+        private async Task DoSwitchCommand(ICollection<PKMember> members)
+        {
+            // Make sure there are no dupes in the list
+            // We do this by checking if removing duplicate member IDs results in a list of different length 
+            if (members.Select(m => m.Id).Distinct().Count() != members.Count) throw Errors.DuplicateSwitchMembers;
+            
+            // Find the last switch and its members if applicable
+            var lastSwitch = await Switches.GetLatestSwitch(Context.SenderSystem);
+            if (lastSwitch != null)
+            {
+                var lastSwitchMembers = await Switches.GetSwitchMembers(lastSwitch);
+                // Make sure the requested switch isn't identical to the last one
+                if (lastSwitchMembers.Select(m => m.Id).SequenceEqual(members.Select(m => m.Id)))
+                    throw Errors.SameSwitch(members);
+            }
+
+            await Switches.RegisterSwitch(Context.SenderSystem, members);
+
+            if (members.Count == 0)
+                await Context.Channel.SendMessageAsync($"{Emojis.Success} Switch-out registered.");
+            else
+                await Context.Channel.SendMessageAsync($"{Emojis.Success} Switch registered. Current fronter is now {string.Join(", ", members.Select(m => m.Name))}.");
+        }
+
+        [Command("move")]
+        [MustHaveSystem]
+        public async Task SwitchMove([Remainder] string str)
+        {
+            var tz = TzdbDateTimeZoneSource.Default.ForId(Context.SenderSystem.UiTz ?? "UTC");
+            
+            var result = PluralKit.Utils.ParseDateTime(str, true, tz);
+            if (result == null) throw Errors.InvalidDateTime(str);
+            
+            var time = result.Value;
+            if (time.ToInstant() > SystemClock.Instance.GetCurrentInstant()) throw Errors.SwitchTimeInFuture;
+
+            // Fetch the last two switches for the system to do bounds checking on
+            var lastTwoSwitches = (await Switches.GetSwitches(Context.SenderSystem, 2)).ToArray();
+            
+            // If we don't have a switch to move, don't bother
+            if (lastTwoSwitches.Length == 0) throw Errors.NoRegisteredSwitches;
+            
+            // If there's a switch *behind* the one we move, we check to make srue we're not moving the time further back than that
+            if (lastTwoSwitches.Length == 2)
+            {
+                if (lastTwoSwitches[1].Timestamp > time.ToInstant())
+                    throw Errors.SwitchMoveBeforeSecondLast(lastTwoSwitches[1].Timestamp.InZone(tz));
+            }
+            
+            // Now we can actually do the move, yay!
+            // But, we do a prompt to confirm.
+            var lastSwitchMembers = await Switches.GetSwitchMembers(lastTwoSwitches[0]);
+            
+            // yeet
+            var msg = await Context.Channel.SendMessageAsync($"{Emojis.Warn} This will move the latest switch ({string.Join(", ", lastSwitchMembers.Select(m => m.Name))}) from {lastTwoSwitches[0].Timestamp.ToString(Formats.DateTimeFormat, null)} ({SystemClock.Instance.GetCurrentInstant().Minus(lastTwoSwitches[0].Timestamp).ToString(Formats.DurationFormat, null)} ago) to {time.ToString(Formats.DateTimeFormat, null)} ({SystemClock.Instance.GetCurrentInstant().Minus(time.ToInstant()).ToString(Formats.DurationFormat, null)} ago). Is this OK?");
+            if (!await Context.PromptYesNo(msg))
+            {
+                throw Errors.SwitchMoveCancelled;
+            }
+            
+            // aaaand *now* we do the move
+            await Switches.MoveSwitch(lastTwoSwitches[0], time.ToInstant());
+            await Context.Channel.SendMessageAsync($"{Emojis.Success} Switch moved.");
+        }
+    }
+}

PluralKit.Bot/Errors.cs

@@ -1,5 +1,9 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
 using System.Net;
 using Humanizer;
+using NodaTime;
 
 namespace PluralKit.Bot {
     public static class Errors {
@@ -35,5 +39,21 @@ namespace PluralKit.Bot {
         public static PKError UnlinkingLastAccount => new PKError("Since this is the only account linked to this system, you cannot unlink it (as that would leave your system account-less).");
         public static PKError MemberLinkCancelled => new PKError("Member link cancelled.");
         public static PKError MemberUnlinkCancelled => new PKError("Member unlink cancelled.");
+
+        public static PKError SameSwitch(ICollection<PKMember> members)
+        {
+            if (members.Count == 0) return new PKError("There's already no one in front.");
+            if (members.Count == 1) return new PKError($"Member {members.First().Name} is already fronting.");
+            return new PKError($"Members {string.Join(", ", members.Select(m => m.Name))} are already fronting.");
+        }
+
+        public static PKError DuplicateSwitchMembers => new PKError("Duplicate members in member list.");
+
+        public static PKError InvalidDateTime(string str) => new PKError($"Could not parse '{str}' as a valid date/time.");
+        public static PKError SwitchTimeInFuture => new PKError("Can't move switch to a time in the future.");
+        public static PKError NoRegisteredSwitches => new PKError("There are no registered switches for this system.");
+
+        public static PKError SwitchMoveBeforeSecondLast(ZonedDateTime time) => new PKError($"Can't move switch to before last switch time ({time.ToString(Formats.DateTimeFormat, null)}), as it would cause conflicts.");
+        public static PKError SwitchMoveCancelled => new PKError("Switch move cancelled.");
     }
 }

PluralKit.Bot/Utils.cs

@@ -118,7 +118,7 @@ namespace PluralKit.Bot
             // do a standard by-hid search.
             var foundByHid = await members.GetByHid(input);
             if (foundByHid != null) return TypeReaderResult.FromSuccess(foundByHid);
-            return TypeReaderResult.FromError(CommandError.ObjectNotFound, "Member not found.");
+            return TypeReaderResult.FromError(CommandError.ObjectNotFound, $"Member '{input}' not found.");
         }
     }