Lunaris2.0/Bot/Handler/MusicPlayer/README.md

README.md

Handlers

Handlers for the Lunaris2 bot, which is built using C#, Discord.Net, and Lavalink4NET. Below is a detailed description of each handler and their responsibilities.

Handlers

ClearQueueHandler

Handles the command to clear the music queue.

public class ClearQueueHandler : IRequestHandler<ClearQueueCommand>

DisconnectHandler

Handles the command to disconnect the bot from the voice channel.

public class DisconnectHandler : IRequestHandler<DisconnectCommand>

PauseHandler

Handles the command to pause the currently playing track.

public class PauseHandler : IRequestHandler<PauseCommand>

PlayHandler

Handles the command to play a track or playlist.

public class PlayHandler : IRequestHandler<PlayCommand>

ResumeHandler

Handles the command to resume the currently paused track.

public class ResumeHandler : IRequestHandler<ResumeCommand>

SkipHandler

Handles the command to skip the currently playing track.

public class SkipHandler : IRequestHandler<SkipCommand>

MessageReceivedHandler

Handles incoming messages and processes commands or statistics requests.

public class MessageReceivedHandler : INotificationHandler<MessageReceivedNotification>

Mermaid Diagrams

Class Diagram

sequenceDiagram
    participant User as User
    participant DiscordSocketClient as DiscordSocketClient
    participant MessageReceivedHandler as MessageReceivedHandler
    participant MessageReceivedNotification as MessageReceivedNotification
    participant EmbedBuilder as EmbedBuilder
    participant Channel as Channel

    User->>DiscordSocketClient: Send message "!LunarisStats"
    DiscordSocketClient->>MessageReceivedHandler: MessageReceivedNotification
    MessageReceivedHandler->>MessageReceivedNotification: Handle(notification, cancellationToken)
    MessageReceivedNotification->>MessageReceivedHandler: BotMentioned(notification, cancellationToken)
    MessageReceivedHandler->>DiscordSocketClient: Get guilds and voice channels
    DiscordSocketClient-->>MessageReceivedHandler: List of guilds and voice channels
    MessageReceivedHandler->>EmbedBuilder: Create embed with statistics
    EmbedBuilder-->>MessageReceivedHandler: Embed
    MessageReceivedHandler->>Channel: Send embed message

Sequence Diagram for PlayHandler

sequenceDiagram
    participant User
    participant Bot
    participant DiscordSocketClient
    participant IAudioService
    participant SocketSlashCommand
    participant LavalinkPlayer

    User->>Bot: /play [song]
    Bot->>DiscordSocketClient: Get user voice channel
    DiscordSocketClient-->>Bot: Voice channel info
    Bot->>IAudioService: Get or create player
    IAudioService-->>Bot: Player instance
    Bot->>SocketSlashCommand: Get search query
    SocketSlashCommand-->>Bot: Search query
    Bot->>IAudioService: Load tracks
    IAudioService-->>Bot: Track collection
    Bot->>LavalinkPlayer: Play track
    LavalinkPlayer-->>Bot: Track started
    Bot->>User: Now playing embed

Sequence Diagram for MessageReceivedHandler

sequenceDiagram
    participant User
    participant Bot
    participant DiscordSocketClient
    participant ISender
    participant MessageReceivedNotification

    User->>Bot: Send message
    Bot->>MessageReceivedNotification: Create notification
    Bot->>DiscordSocketClient: Check if bot is mentioned
    DiscordSocketClient-->>Bot: Mention info
    alt Bot is mentioned
        Bot->>ISender: Send ChatCommand
    end
    Bot->>DiscordSocketClient: Check for statistics command
    alt Statistics command found
        Bot->>DiscordSocketClient: Get server and channel info
        DiscordSocketClient-->>Bot: Server and channel info
        Bot->>User: Send statistics embed
    end

Extensions.cs

Namespaces

• Discord: Provides classes for interacting with Discord.
• Discord.WebSocket: Provides WebSocket-specific classes for Discord.
• Lavalink4NET: Provides classes for interacting with Lavalink.
• Lavalink4NET.Players: Provides player-related classes for Lavalink.
• Lavalink4NET.Players.Queued: Provides queued player-related classes for Lavalink.
• Microsoft.Extensions.Options: Provides classes for handling options and configurations.

Class: Extensions

This static class contains extension methods for various Discord and Lavalink operations.

Method: GetPlayerAsync

• Parameters:
  • IAudioService audioService: The audio service to retrieve the player from.
  • DiscordSocketClient client: The Discord client.
  • SocketSlashCommand context: The context of the slash command.
  • bool connectToVoiceChannel: Whether to connect to the voice channel (default is true).
• Returns: ValueTask<QueuedLavalinkPlayer?>
• Description: Retrieves a QueuedLavalinkPlayer for the given context. If the retrieval fails, it returns null and sends an appropriate error message.

Method: GetGuild

• Parameters:
  • SocketSlashCommand message: The slash command message.
  • DiscordSocketClient client: The Discord client.
• Returns: SocketGuild
• Description: Retrieves the guild associated with the given slash command message. Throws an exception if the guild ID is null.

Method: GetVoiceState

• Parameters:
  • SocketSlashCommand message: The slash command message.
• Returns: IVoiceState
• Description: Retrieves the voice state of the user who issued the slash command. Throws an exception if the user is not connected to a voice channel.

Method: RespondAsync

• Parameters:
  • SocketSlashCommand message: The slash command message.
  • string content: The content of the response.
• Returns: Task
• Description: Sends an ephemeral response to the slash command.

Method: GetOptionValueByName

• Parameters:
  • SocketSlashCommand command: The slash command.
  • string optionName: The name of the option to retrieve the value for.
• Returns: string
• Description: Retrieves the value of the specified option from the slash command. Returns an empty string if the option is not found.

MessageModule

The MessageModule class provides utility methods for sending and removing messages in a Discord guild using the Discord.Net library. It maintains a dictionary to keep track of message IDs for each guild, allowing for easy removal of messages when needed.

Methods

SendMessageAsync(SocketSlashCommand context, string message, DiscordSocketClient client)

Sends a follow-up message with the specified text content in response to a slash command.

• Parameters:
  • context: The SocketSlashCommand context in which the command was executed.
  • message: The text content of the message to be sent.
  • client: The DiscordSocketClient instance.

SendMessageAsync(SocketSlashCommand context, Embed message, DiscordSocketClient client)

Sends a follow-up message with the specified embed content in response to a slash command.

• Parameters:
  • context: The SocketSlashCommand context in which the command was executed.
  • message: The Embed content of the message to be sent.
  • client: The DiscordSocketClient instance.

RemoveMessages(SocketSlashCommand context, DiscordSocketClient client)

Removes all tracked messages for the guild in which the command was executed.

• Parameters:
  • context: The SocketSlashCommand context in which the command was executed.
  • client: The DiscordSocketClient instance.

StoreForRemoval(SocketSlashCommand context, DiscordSocketClient client)

Stores the message ID for removal and deletes any previously tracked messages for the guild.

• Parameters:

  • context: The SocketSlashCommand context in which the command was executed.
  • client: The DiscordSocketClient instance.

• Returns:

  • The guild ID as a ulong.

Usage

To use the MessageModule class, simply call the appropriate method from your command handling logic. For example:

await context.SendMessageAsync("Hello, world!", client);

This will send a follow-up message with the text "Hello, world!" in response to the slash command.