Subissue: Lift chat input state to ChatModel

[dlqqq]

Problem

While building #161, I noticed that I had to pass input and setInput from the <ChatInput /> component to the chat command providers, since they need to read & write from the input. This results in a weird interface:

export interface IChatCommandProvider {
    id: string;
    ready?: Promise<void>;
    getChatCommands(partialInput: string): Promise<ChatCommand[]>;
    handleChatCommand(command: ChatCommand, partialInput: string, replacePartialInput: (newPartialInput: string) => void): Promise<void>;
}

If a ChatModel instance could provide methods for reading & writing to the input, the interface can then be simplified to:

export interface IChatCommandProvider {
    id: string;
    ready?: Promise<void>;
    getChatCommands(chatModel: IChatModel): Promise<ChatCommand[]>;
    handleChatCommand(command: ChatCommand, chatModel: IChatModel): Promise<void>;
}

Proposed Solution

Lift chat input state up to the ChatModel instance. The <ChatInput /> component should be updated accordingly.

Additional context

Chat commands PR: #161

[dlqqq]

Discussed this briefly with @brichet on Thursday 02/13. Nicolas mentioned that it may make more sense for this to live in a InputModel under the ChatModel. This sounds reasonable to me since it namespaces methods for getting & setting the input under chatModel.input.

[dlqqq]

@brichet Here is an interface that describes the methods & properties needed by the Chat Commands framework:

interface IInputModel {
  /* the entire input */
  get value(): string
  set value(newInput: string): void
  valueChanged: ISignal<IInputModel, string>;

  /**
   * the current cursor index.
   * this refers to the index of the character in front of the cursor.
   */
  get cursorIndex(): number
  set cursorIndex(newIndex: number): void
  cursorIndexChanged: ISignal<IInputModel, number>

  /**
   * the current word behind the user's cursor, space-separated.
   * should call functions defined under `input/utils.ts`.
   */
  get currentWord(): string
  set currentWord(newWord: string): void
  currentWordChanged: ISignal<IInputModel, string>;
}