const privacyAuthorizationHandlers = []
let hasBoundPrivacyAuthorizationListener = false

function getActivePrivacyAuthorizationHandler() {
  return privacyAuthorizationHandlers.length
    ? privacyAuthorizationHandlers[privacyAuthorizationHandlers.length - 1]
    : null
}

export function bindPrivacyAuthorizationListener(handler) {
  if (typeof handler !== 'function') {
    return
  }

  const existedIndex = privacyAuthorizationHandlers.indexOf(handler)
  if (existedIndex !== -1) {
    privacyAuthorizationHandlers.splice(existedIndex, 1)
  }
  privacyAuthorizationHandlers.push(handler)

  // #ifdef MP-WEIXIN
  if (hasBoundPrivacyAuthorizationListener || typeof wx === 'undefined' || !wx.onNeedPrivacyAuthorization) {
    return
  }

  wx.onNeedPrivacyAuthorization((resolve) => {
    const activeHandler = getActivePrivacyAuthorizationHandler()
    if (typeof activeHandler === 'function') {
      activeHandler(resolve)
    }
  })
  hasBoundPrivacyAuthorizationListener = true
  // #endif
}

export function unbindPrivacyAuthorizationListener(handler) {
  const existedIndex = privacyAuthorizationHandlers.lastIndexOf(handler)
  if (existedIndex !== -1) {
    privacyAuthorizationHandlers.splice(existedIndex, 1)
  }
}

export function getPrivacyAuthorizationStatus() {
  // #ifdef MP-WEIXIN
  return new Promise((resolve) => {
    if (typeof wx === 'undefined' || !wx.getPrivacySetting) {
      resolve({ needAuthorization: false })
      return
    }

    wx.getPrivacySetting({
      success: (res) => {
        resolve({
          ...res,
          needAuthorization: !!(res && res.needAuthorization)
        })
      },
      fail: () => {
        resolve({ needAuthorization: false })
      }
    })
  })
  // #endif
  // #ifndef MP-WEIXIN
  return Promise.resolve({ needAuthorization: false })
  // #endif
}

export function openWechatPrivacyContract() {
  // #ifdef MP-WEIXIN
  return new Promise((resolve, reject) => {
    if (typeof wx === 'undefined' || !wx.openPrivacyContract) {
      resolve()
      return
    }

    wx.openPrivacyContract({
      success: resolve,
      fail: reject
    })
  })
  // #endif
  // #ifndef MP-WEIXIN
  return Promise.resolve()
  // #endif
}