About

mruby-tui-chat provides a conversation widget for mruby-tui, optimized for AI chat interfaces. It supports word-wrapped text, role-prefixed messages, segmented rendering with colours, markdown AST content, and scroll.

Quick start

Basic chat

chat = TUI::Chat.new
chat.add(:user, "Hello")
chat.add(:assistant, "Hi there!")

Streaming output

chat = TUI::Chat.new
chat.replace_last(:assistant, "")
chat.append(:assistant, "Hello")
chat.append(:assistant, " world")

Markdown AST

ast = Markdown.new("# Hello\n\n**world**").ast
chat.replace_last(:assistant, ast)

Without role labels

chat = TUI::Chat.new(show_roles: false)
chat.add(:user, "just the message")

Features

TUI::Chat.new
Creates a chat widget with configurable foreground colours for user, assistant, and text, plus a background colour.

TUI::Chat#add
Appends a new message with the given role and text.

TUI::Chat#append
Appends text to the last message for the given role, or creates one if no matching message exists. Used for streaming output where content arrives incrementally.

TUI::Chat#replace_last
Replaces the last message for the given role. Used for updating a streaming response in place. Messages may be plain strings, segment arrays, or markdown AST hashes from mruby-markdown. Pass follow: true to scroll to the newest message while replacing the message.

TUI::Chat#scroll_up
Scrolls the view upward by one rendered row.

TUI::Chat#scroll_down
Scrolls the view downward by one rendered row.

TUI::Chat#append and TUI::Chat#replace_last
Both methods preserve the current visible viewport by default. Pass follow: true when an update should pull the viewport to the bottom.

TUI::Chat#follow!
Returns the viewport to the newest message. This is useful after manual scrolling when new input or streamed output should resume following the bottom of the conversation.

Integration

Add to your mruby build config:

MRuby::Build.new("app") do |conf|
  conf.toolchain
  conf.gembox "default"
  conf.gem github: "mrbgemz/mruby-tui-chat", branch: "main"
end

Dependencies are declared in mrbgem.rake:

Dependency	Purpose
mruby-tui	Widget base class, TUI.print, Utils

License

BSD Zero Clause
See LICENSE