Chat Lifecycle Signals

import { InjectionToken, Signal } from '@angular/core';
 
export interface ChatLifecycle {
  /** True after <chat> initializes with a non-null agent binding. */
  readonly componentReady: Signal<boolean>;
  /** True after the first user submit. Sticky for the life of the chat instance — does NOT reset on clearThread. */
  readonly firstMessageSent: Signal<boolean>;
  /** Count of user submits. Resets on clearThread. */
  readonly messageCount: Signal<number>;
  /** Epoch ms of the most recent user submit. Resets on clearThread. */
  readonly inputSubmittedAt: Signal<number | null>;
}
 
export const CHAT_LIFECYCLE = new InjectionToken<ChatLifecycle>('CHAT_LIFECYCLE');

import { Component, inject, effect } from '@angular/core';
import { CHAT_LIFECYCLE } from '@threadplane/chat';
 
@Component({ /* ... */ })
export class MyComponent {
  private lifecycle = inject(CHAT_LIFECYCLE);
 
  constructor() {
    effect(() => {
      if (this.lifecycle.firstMessageSent()) {
        console.log('User sent their first message at', this.lifecycle.inputSubmittedAt());
      }
    });
  }
}