!7

abstract sclass DynConvo > DynModule {
  L<JChatConvo.Post> posts_raw = new L; // underlying list
  transient L<JChatConvo.Post> posts; // list with notify

  S userInput;
  
  transient JChatConvo view;
  
  start {
    posts = dm_synchroList(this, posts_raw);
  }
  
  Pt minimumSize() { ret pt(300, 300); }
  
  O[] menuItems() {
    ret litarray("Clear", rEnter clearPosts);
  }
  
  visualize {
    print("Have posts: " + posts);
    view = swing(() -> new JChatConvo);
    view.usePostsList(posts);
    ret centerAndSouth(
      jscroll_trackWidth(view),
      withMargin(bottomPart()));
  }
  
  JComponent bottomPart() {
    ret dm_textFieldAndSubmit userInput('sendInput, buttonText := "Send");
  }
  
  void sendInput {
    S s = trim(userInput);
    if (nempty(s)) {
      setField(userInput := "");
      sendInput2(s);
    }
  }

  void sendInput2(S s) {  
    if "clear"
      ret with clearPosts();
    addPost(htmlEncode2(s), false);
    vmBus_send chatUserInput(module(), s);
  }
  
  // API
  
  void addPost(S html, bool right) swing {
    JChatConvo.Post post = new(html, right);
    posts.add(post);
    programLog("New post: " + struct(post));
    view?.updateAndScrollDown();
  }
  
  void clearPosts swing {
    posts.clear();
    programLog("Cleared posts");
    view?.updateAndScrollDown();
  }
  
  void reply(S s) {
    if (empty(s = trim(s))) ret;
    addPost(htmlEncode2(s), true);
  }
  
  S lastInput() {
    for (Post p : lazyReversed(posts))
      if (!p.right)
        ret p.html;
    null;
  }
}