import type { Task, Message, ExecutionResult } from '@/types';

const STORAGE_KEY = 'professor_session';

export interface LocalSession {
  topicId: string;
  task: Task;
  code: string;
  messages: Message[];
  executionResult: ExecutionResult | null;
}

export function saveLocalSession(session: LocalSession): void {
  if (typeof window === 'undefined') return;
  try {
    localStorage.setItem(STORAGE_KEY, JSON.stringify(session));
  } catch {
    // Ignore quota errors
  }
}

export function loadLocalSession(): LocalSession | null {
  if (typeof window === 'undefined') return null;
  try {
    const raw = localStorage.getItem(STORAGE_KEY);
    if (!raw) return null;
    return JSON.parse(raw) as LocalSession;
  } catch {
    return null;
  }
}

export function clearLocalSession(): void {
  if (typeof window === 'undefined') return;
  localStorage.removeItem(STORAGE_KEY);
}