// 简化的Fiber节点结构
class Fiber {
  constructor(tag, key, pendingProps) {
    this.tag = tag;
    this.key = key;
    this.pendingProps = pendingProps;
    this.return = null;
    this.child = null;
    this.sibling = null;
    this.alternate = null;
    this.effectTag = 0;
    this.nextEffect = null;
  }
}

// 简化的调度器
class Scheduler {
  constructor() {
    this.taskQueue = [];
    this.currentTask = null;
  }

  scheduleTask(task, priority) {
    this.taskQueue.push({ task, priority });
    this.taskQueue.sort((a, b) => b.priority - a.priority);
  }

  performWork(deadline) {
    while ((this.currentTask = this.taskQueue.shift()) && deadline.timeRemaining() > 0) {
      this.currentTask.task();
    }
    
    if (this.taskQueue.length > 0) {
      requestIdleCallback(this.performWork.bind(this));
    }
  }

  start() {
    requestIdleCallback(this.performWork.bind(this));
  }
}

// 简化的协调器（Reconciler）
function reconcile(currentFiber, element) {
  let newFiber;
  if (currentFiber == null) {
    newFiber = new Fiber(element.type, element.key, element.props);
  } else if (element == null) {
    // 删除节点
    currentFiber.effectTag = 'DELETION';
  } else if (currentFiber.type === element.type) {
    // 更新节点
    newFiber = new Fiber(element.type, element.key, element.props);
    newFiber.alternate = currentFiber;
    newFiber.effectTag = 'UPDATE';
  } else {
    // 替换节点
    newFiber = new Fiber(element.type, element.key, element.props);
    newFiber.effectTag = 'PLACEMENT';
  }
  return newFiber;
}

// 使用示例
const scheduler = new Scheduler();

function updateComponent(fiber) {
  console.log('Updating component:', fiber.key);
  // 模拟组件更新
}

scheduler.scheduleTask(() => updateComponent(new Fiber('div', 'root', {})), 1);
scheduler.scheduleTask(() => updateComponent(new Fiber('span', 'child1', {})), 2);
scheduler.scheduleTask(() => updateComponent(new Fiber('p', 'child2', {})), 3);

scheduler.start();