const app = getApp()

function safeDecode(value) {
  try {
    return decodeURIComponent(value || '')
  } catch (_) {
    return String(value || '')
  }
}

function normalizeHttpUrl(raw) {
  let s = String(raw || '').trim()
  if (!s) return ''
  if (/^\/\//.test(s)) return 'https:' + s
  if (!/^https?:\/\//i.test(s)) s = 'https://' + s.replace(/^\/+/, '')
  return s
}

// 为外链补充移动端提示参数：目标站支持时按手机网页输出
function appendMobileHints(rawUrl) {
  const url = normalizeHttpUrl(rawUrl)
  if (!url) return ''
  const hasQuery = url.indexOf('?') >= 0
  const hasFrom = /(?:\?|&)from=/i.test(url)
  const hasView = /(?:\?|&)view=/i.test(url)
  const extras = []
  if (!hasFrom) extras.push('from=miniprogram')
  if (!hasView) extras.push('view=mobile')
  if (!extras.length) return url
  return url + (hasQuery ? '&' : '?') + extras.join('&')
}

Page({
  data: {
    url: '',
    title: '链接预览',
    statusBarHeight: 44,
    navBarHeight: 88,
    loadError: false,
  },

  onLoad(options) {
    const rawUrl = safeDecode(options.url || '')
    const url = appendMobileHints(rawUrl)
    const title = options.title ? safeDecode(options.title) : '链接预览'
    this.setData({
      url,
      title,
      statusBarHeight: app.globalData.statusBarHeight || 44,
      navBarHeight: app.globalData.navBarHeight || 88,
    })
  },

  onWebViewError() {
    this.setData({ loadError: true })
    wx.showModal({
      title: '无法在小程序内打开',
      content: '该链接无法在小程序内预览，是否复制链接到浏览器打开？',
      confirmText: '复制链接',
      cancelText: '返回',
      success: (res) => {
        if (res.confirm) {
          wx.setClipboardData({
            data: this.data.url,
            success: () => wx.showToast({ title: '链接已复制，请在浏览器打开', icon: 'none', duration: 2000 }),
          })
        } else {
          this.goBack()
        }
      },
    })
  },

  goBack() {
    const pages = getCurrentPages()
    if (pages.length > 1) {
      wx.navigateBack()
    } else {
      wx.switchTab({ url: '/pages/index/index' })
    }
  },

  copyLink() {
    const url = (this.data.url || '').trim()
    if (!url) {
      wx.showToast({ title: '暂无可复制链接', icon: 'none' })
      return
    }
    wx.setClipboardData({
      data: url,
      success: () => wx.showToast({ title: '链接已复制', icon: 'none' }),
    })
  },
})