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.