class ComprehensiveURLObserver {
  constructor(options = {}) {
    this.options = {
      trackHash: true,
      trackSearch: true,
      trackPathname: true,
      debounce: 50,
      ...options
    }

    this.observers = []
    this.lastUrl = this.getCurrentURLState()
    this.debounceTimer = null
    this.init()
  }

  init() {
    // 监听标准事件
    window.addEventListener('popstate', this.handleChange.bind(this))

    if (this.options.trackHash) {
      window.addEventListener('hashchange', this.handleChange.bind(this))
    }

    // 拦截 History API
    this.interceptHistoryMethods()

    // 监听点击事件（捕获链接点击）
    document.addEventListener('click', this.handleClick.bind(this), true)

    // 可选：轮询作为备用方案
    if (this.options.polling) {
      this.startPolling()
    }
  }

  getCurrentURLState() {
    return {
      href: window.location.href,
      pathname: window.location.pathname,
      search: window.location.search,
      hash: window.location.hash,
      origin: window.location.origin
    }
  }

  interceptHistoryMethods() {
    const methods = ['pushState', 'replaceState']

    methods.forEach(method => {
      const original = history[method]
      history[method] = (...args) => {
        const oldState = this.getCurrentURLState()
        const result = original.apply(history, args)
        this.handleChange('history', oldState)
        return result
      }
    })
  }

  handleClick(event) {
    const link = event.target.closest('a')
    if (link && link.href) {
      const targetUrl = new URL(link.href, window.location.origin)
      const currentUrl = new URL(window.location.href)

      // 如果是同源导航且不是当前页面
      if (targetUrl.origin === currentUrl.origin &&
                targetUrl.href !== currentUrl.href) {
        event.preventDefault()

        this.handleChange('click', this.getCurrentURLState())

        // 执行实际导航
        setTimeout(() => {
          window.location.href = link.href
        }, 0)
      }
    }
  }

  handleChange(type, oldState = this.lastUrl) {
    if (this.debounceTimer) {
      clearTimeout(this.debounceTimer)
    }

    this.debounceTimer = setTimeout(() => {
      const newState = this.getCurrentURLState()

      if (this.hasUrlChanged(oldState, newState)) {
        const changeInfo = {
          oldUrl: oldState.href,
          newUrl: newState.href,
          type: type,
          timestamp: Date.now(),
          details: {
            pathname: { old: oldState.pathname, new: newState.pathname },
            search: { old: oldState.search, new: newState.search },
            hash: { old: oldState.hash, new: newState.hash }
          }
        }

        this.notifyObservers(changeInfo)
        this.lastUrl = newState
      }
    }, this.options.debounce)
  }

  hasUrlChanged(oldState, newState) {
    if (oldState.href !== newState.href) return true

    if (this.options.trackPathname && oldState.pathname !== newState.pathname) return true
    if (this.options.trackSearch && oldState.search !== newState.search) return true
    if (this.options.trackHash && oldState.hash !== newState.hash) return true

    return false
  }

  startPolling() {
    setInterval(() => {
      const currentState = this.getCurrentURLState()
      if (this.hasUrlChanged(this.lastUrl, currentState)) {
        this.handleChange('polling', this.lastUrl)
      }
    }, this.options.pollingInterval || 1000)
  }

  subscribe(callback) {
    this.observers.push(callback)
    return () => this.unsubscribe(callback)
  }

  unsubscribe(callback) {
    this.observers = this.observers.filter(obs => obs !== callback)
  }

  notifyObservers(changeInfo) {
    this.observers.forEach(observer => {
      try {
        observer(changeInfo)
      } catch (error) {
        console.error('URL观察者错误:', error)
      }
    })
  }

  destroy() {
    window.removeEventListener('popstate', this.handleChange)
    window.removeEventListener('hashchange', this.handleChange)
    document.removeEventListener('click', this.handleClick)

    if (this.debounceTimer) {
      clearTimeout(this.debounceTimer)
    }
  }
}

// const unsubscribe = urlWatcher.subscribe((change) => {
//     console.group('URL变化详情');
//     console.log('类型:', change.type);
//     console.log('从:', change.oldUrl);
//     console.log('到:', change.newUrl);
//     console.log('路径变化:', change.details.pathname);
//     console.log('查询参数变化:', change.details.search);
//     console.log('哈希变化:', change.details.hash);
//     console.groupEnd();
// });
export default {
  urlWatcher: new ComprehensiveURLObserver({
    trackHash: true,
    trackSearch: true,
    trackPathname: true,
    debounce: 100
  })
}