TentacleBot/Services/BotService.cs

using Discord;
using Discord.WebSocket;
using Discord.Interactions;
using Microsoft.Extensions.Logging;
using Microsoft.Extensions.Configuration;

namespace TentacleBot.Services;

public class BotService
{
    private readonly DiscordSocketClient _client;
    private readonly InteractionService _interactionService;
    private readonly ILogger<BotService> _logger;
    private readonly IConfiguration _configuration;
    private readonly IServiceProvider _serviceProvider;

    public BotService(
        DiscordSocketClient client,
        InteractionService interactionService,
        ILogger<BotService> logger,
        IConfiguration configuration,
        IServiceProvider serviceProvider)
    {
        _client = client;
        _interactionService = interactionService;
        _logger = logger;
        _configuration = configuration;
        _serviceProvider = serviceProvider;
    }

    public async Task InitializeAsync()
    {
        _client.Log += LogAsync;
        _interactionService.Log += LogAsync;

        _client.Ready += ClientReadyAsync;
        _client.InteractionCreated += InteractionCreatedAsync;

        var token = Environment.GetEnvironmentVariable("DISCORD_BOT_TOKEN");
        if (string.IsNullOrWhiteSpace(token))
        {
            token = _configuration["Discord:BotToken"];
        }

        if (string.IsNullOrEmpty(token))
        {
            throw new InvalidOperationException("Discord bot token not found. Set DISCORD_BOT_TOKEN or Discord:BotToken in appsettings.json");
        }

        await _client.LoginAsync(TokenType.Bot, token);
        await _client.StartAsync();

        _logger.LogInformation("Bot service initialized");
    }

    private async Task ClientReadyAsync()
    {
        _logger.LogInformation("Bot connected as {BotName}#{Discriminator}", _client.CurrentUser?.Username, _client.CurrentUser?.Discriminator);

        // Register slash commands
        await _interactionService.RegisterCommandsGloballyAsync();

        _logger.LogInformation("Slash commands registered");
    }

    private async Task InteractionCreatedAsync(SocketInteraction interaction)
    {
        try
        {
            var ctx = new SocketInteractionContext(_client, interaction);
            await _interactionService.ExecuteCommandAsync(ctx, _serviceProvider);
        }
        catch (Exception ex)
        {
            _logger.LogError(ex, "Error handling interaction");

            if (interaction.Type == InteractionType.ApplicationCommand)
            {
                await interaction.GetOriginalResponseAsync().ContinueWith(async msg =>
                {
                    if (msg.IsCompletedSuccessfully)
                    {
                        await interaction.FollowupAsync("An error occurred while executing the command.");
                    }
                });
            }
        }
    }

    private static Task LogAsync(LogMessage message)
    {
        Console.WriteLine($"[{message.Severity}] {message.Source}: {message.Message}");
        return Task.CompletedTask;
    }

    public async Task StopAsync()
    {
        await _client.StopAsync();
        _client.Dispose();
        _logger.LogInformation("Bot service stopped");
    }
}