GmRelayBot/src/GmRelay.DiscordBot/Features/Sessions/DiscordNewSessionCommand.cs

using GmRelay.DiscordBot.Rendering;
using NetCord.Rest;
using NetCord.Services.ApplicationCommands;

namespace GmRelay.DiscordBot.Features.Sessions;

[SlashCommand("newsession", "Create a new game session")]
public class DiscordNewSessionCommand : ApplicationCommandModule<SlashCommandContext>
{
    private readonly DiscordNewSessionHandler _handler;
    private readonly ILogger<DiscordNewSessionCommand> _logger;

    public DiscordNewSessionCommand(DiscordNewSessionHandler handler, ILogger<DiscordNewSessionCommand> logger)
    {
        _handler = handler;
        _logger = logger;
    }

    public async Task ExecuteAsync(
        [SlashCommandParameter(Name = "title", Description = "Game title")] string title,
        [SlashCommandParameter(Name = "time", Description = "Session time (YYYY-MM-DD HH:mm or DD.MM.YYYY HH:mm)")] string time,
        [SlashCommandParameter(Name = "seats", Description = "Maximum number of players")] long? seats = null,
        [SlashCommandParameter(Name = "link", Description = "Join link")] string? link = null)
    {
        var guild = Context.Guild
            ?? throw new InvalidOperationException("This command can only be used in a guild.");

        var timeResult = DiscordNewSessionHandler.ParseTimeInput(time);
        if (!timeResult.IsSuccess)
        {
            await Context.Interaction.SendResponseAsync(
                InteractionCallback.Message($"X {timeResult.Error}"));
            return;
        }

        var resolvedPermissions = GetResolvedPermissions(guild, Context.User.Id);

        try
        {
            var view = await _handler.HandleAsync(
                guildId: guild.Id.ToString(),
                channelId: Context.Channel.Id.ToString(),
                userId: Context.User.Id,
                userDisplayName: Context.User.GlobalName ?? Context.User.Username,
                resolvedPermissions: resolvedPermissions,
                guildOwnerId: guild.OwnerId,
                title: title,
                scheduledAt: timeResult.Value,
                maxPlayers: seats is null ? null : (int)seats.Value,
                joinLink: link,
                CancellationToken.None);

            var (embeds, actionRows) = DiscordSessionBatchRenderer.Render(view);
            await Context.Interaction.SendResponseAsync(
                InteractionCallback.Message(new InteractionMessageProperties()
                    .WithContent(":white_check_mark: **Session created successfully!**")
                    .WithEmbeds(embeds)
                    .WithComponents(actionRows)));
        }
        catch (UnauthorizedAccessException ex)
        {
            await Context.Interaction.SendResponseAsync(
                InteractionCallback.Message($":no_entry: {ex.Message}"));
        }
        catch (Exception ex)
        {
            _logger.LogError(ex, "Failed to create session for user {UserId} in guild {GuildId}", Context.User.Id, guild.Id);
            await Context.Interaction.SendResponseAsync(
                InteractionCallback.Message(":boom: An error occurred while creating the session."));
        }
    }

    private static ulong GetResolvedPermissions(NetCord.Gateway.Guild guild, ulong userId)
    {
        if (!guild.Users.TryGetValue(userId, out var guildUser))
            return 0;

        ulong resolved = 0;
        foreach (var roleId in guildUser.RoleIds)
        {
            if (guild.Roles.TryGetValue(roleId, out var role))
                resolved |= (ulong)role.Permissions;
        }

        return resolved;
    }
}