// WebSocket 进度（可被 node --test 单测的纯逻辑部分）
export interface ProgressEvent { type?: string; step?: string; detail?: string; }
export interface WsHandlers { onProgress?: (e: ProgressEvent) => void; onClose?: () => void; }
export type RenderFn = (role: string, text: string) => void;

export function connectProgressWs(sid: string, handlers: WsHandlers): WebSocket | null {
  const proto = location.protocol === 'https:' ? 'wss' : 'ws';
  let ws: WebSocket;
  try {
    ws = new WebSocket(proto + '://' + location.host + '/api/sessions/' + encodeURIComponent(sid) + '/ws');
  } catch (err) {
    if (handlers.onClose) handlers.onClose();
    return null;
  }
  ws.onmessage = (ev: MessageEvent) => {
    let e: ProgressEvent;
    try { e = JSON.parse(ev.data as string) as ProgressEvent; } catch { return; }
    if (handlers.onProgress) handlers.onProgress(e);
  };
  ws.onerror = () => { try { ws.close(); } catch { /* ignore */ } };
  ws.onclose = () => { if (handlers.onClose) handlers.onClose(); };
  return ws;
}

export function applyProgressEvent(e: ProgressEvent, render: RenderFn): void {
  if (e.type === 'progress') render('progress', (e.step || '') + ': ' + (e.detail || ''));
  else if (e.type === 'error') render('error', e.detail || '错误');
}