deerflow-code/frontend-web/src/open-canvas/hooks/useAIWritingSessions.ts

import { useCallback, useMemo, useState } from 'react';

import {
  listAIWritingSessions,
  renameAIWritingSession,
  deleteAIWritingSession,
} from '../api/ai-writing-sessions';
import type { AIWritingSessionSummary } from '../api/ai-writing-sessions';

export function useAIWritingSessions() {
  const [sessions, setSessions] = useState<AIWritingSessionSummary[]>([]);
  const [loading, setLoading] = useState(false);
  // 「后台挂起」乐观标记：点击挂起后立刻让历史下拉显示「挂起中」，不必等后端确认。
  // 后端状态（status='background'）刷新到位后由调用方 clearBackground 清除。
  const [pendingBackground, setPendingBackground] = useState<Set<string>>(() => new Set());

  const markBackground = useCallback((id: string) => {
    setPendingBackground((prev) => {
      if (prev.has(id)) return prev;
      const next = new Set(prev);
      next.add(id);
      return next;
    });
  }, []);

  const clearBackground = useCallback((id: string) => {
    setPendingBackground((prev) => {
      if (!prev.has(id)) return prev;
      const next = new Set(prev);
      next.delete(id);
      return next;
    });
  }, []);

  const refresh = useCallback(async () => {
    setLoading(true);
    try {
      const data = await listAIWritingSessions();
      setSessions(data);
    } catch {
      // silently ignore — history is non-critical
    } finally {
      setLoading(false);
    }
  }, []);

  const rename = useCallback(async (id: string, title: string) => {
    try {
      const updated = await renameAIWritingSession(id, title);
      setSessions((prev) => prev.map((s) => (s.id === id ? updated : s)));
    } catch {
      // ignore
    }
  }, []);

  const remove = useCallback(async (id: string) => {
    try {
      await deleteAIWritingSession(id);
      setSessions((prev) => prev.filter((s) => s.id !== id));
    } catch {
      // ignore
    }
  }, []);

  // 把乐观「挂起中」标记叠加到真实列表上：已在列表里的会话立刻显示 background。
  const displaySessions = useMemo(
    () =>
      pendingBackground.size === 0
        ? sessions
        : sessions.map((s) =>
            pendingBackground.has(s.id) && s.status !== 'done'
              ? { ...s, status: 'background' }
              : s,
          ),
    [sessions, pendingBackground],
  );

  return { sessions: displaySessions, loading, refresh, rename, remove, markBackground, clearBackground };
}