// composables/useWindowWidth.ts
import { ref, onMounted, onBeforeUnmount, type Ref } from 'vue'

// 同步获取当前窗口宽度
function getCurrentWidth(): number {
  // #ifdef H5
  if (typeof window !== 'undefined') {
    return window.innerWidth
  }
  // #endif

  // #ifdef APP-PLUS
  // @ts-ignore
  if (typeof uni !== 'undefined' && uni.getSystemInfoSync) {
    // @ts-ignore
    const systemInfo = uni.getSystemInfoSync()
    return systemInfo.windowWidth
  }
  // #endif

  return 0 // 兜底值
}

export function useWindowWidth(debounceMs: number = 0): Ref<number> {
  // ✅ 关键：立即同步获取宽度，不再初始为 0
  const width = ref(getCurrentWidth())

  let timer: ReturnType<typeof setTimeout> | null = null
  let resizeHandler: (res?: any) => void

  const updateWidth = () => {
    width.value = getCurrentWidth()
  }

  if (debounceMs > 0) {
    resizeHandler = () => {
      if (timer) clearTimeout(timer)
      timer = setTimeout(() => {
        updateWidth()
        timer = null
      }, debounceMs)
    }
  } else {
    resizeHandler = updateWidth
  }

  onMounted(() => {
    // 确保宽度最新（如屏幕旋转后组件才挂载的极端情况）
    updateWidth()

    // #ifdef H5
    if (typeof window !== 'undefined') {
      window.addEventListener('resize', resizeHandler)
    }
    // #endif

    // #ifdef APP-PLUS
    // @ts-ignore
    if (typeof uni !== 'undefined' && uni.onWindowResize) {
      // @ts-ignore
      uni.onWindowResize(resizeHandler)
    }
    // #endif
  })

  onBeforeUnmount(() => {
    if (timer) clearTimeout(timer)

    // #ifdef H5
    if (typeof window !== 'undefined') {
      window.removeEventListener('resize', resizeHandler)
    }
    // #endif

    // #ifdef APP-PLUS
    // @ts-ignore
    if (typeof uni !== 'undefined' && uni.offWindowResize) {
      // @ts-ignore
      uni.offWindowResize(resizeHandler)
    }
    // #endif
  })

  return width
}