import { writeA7Payload } from '../core/packet'
import { waitForProtocolState } from '../core/stateWait'

const WIFI_FINAL_STATE_CODES = Object.freeze([1, 2, 3])

/**
 * 校验 WiFi 入参，规则来源于 profile.wifi。
 */
function validateWifi(profile, ssid, password) {
  const errors = []

  if (!ssid || ssid.length > profile.wifi.maxSsidLength) {
    errors.push(`SSID 长度需在 1-${profile.wifi.maxSsidLength} 之间`)
  }

  if (password.length < profile.wifi.minPasswordLength || password.length > profile.wifi.maxPasswordLength) {
    errors.push(`密码长度需在 ${profile.wifi.minPasswordLength}-${profile.wifi.maxPasswordLength} 之间`)
  }

  const invalidChars = profile.wifi.invalidChars || []
  if (invalidChars.some((char) => ssid.includes(char))) {
    errors.push(`SSID 不能包含特殊字符: ${invalidChars.join(' ')}`)
  }

  if (errors.length) {
    throw new Error(errors.join('；'))
  }
}

function requireAuthorized(ble) {
  const state = ble.getState()

  if (!state.auth || state.auth.keyMatched !== true) {
    throw new Error('请先完成密钥鉴权，再发送 WiFi 配置')
  }
}

/**
 * WiFi 配网模块：负责打包发送 ssid|password，并等待 STATE 回执。
 */
export function createWifiModule(ble) {
  function delay(ms) {
    return new Promise((resolve) => setTimeout(resolve, Number(ms) || 0))
  }
  const log = (...args) => { try { console.debug('[BLE][WiFi]', ...args) } catch (e) {} }

  async function configureWifi(ssid, password, options = {}) {
    const profile = ble.getProfile()
    const s = String(ssid || '').trim(), p = String(password || '').trim()
    validateWifi(profile, s, p); requireAuthorized(ble)
    const { wifi } = ble.getState().characteristics; if (!wifi || !wifi.uuid) throw new Error('未发现 UUID_WIFI 特征值')
    const waitPromise = waitForProtocolState(ble, { allowedCodes: WIFI_FINAL_STATE_CODES, rejectOnUnexpected: false, timeout: options.timeout || 12000, timeoutMessage: '等待 WiFi 状态超时' })
    const pre = options.preDelayMs ?? (ble.getProfile().id === 'ED713' ? 120 : 0); if (pre) { log('preDelay before WiFi write(ms)=', pre); await delay(pre) }
    log('write WiFi start', { service: ble.getState().serviceId, char: wifi.uuid })
    const sent = await writeA7Payload(ble, wifi.uuid, `${s}|${p}`, profile.packet, { packetInterval: Number(options.packetInterval) || 0 })
    log('write WiFi done, packets=', sent)
    const code = Number((await waitPromise).stateCode); log('STATE(final) received for WiFi=', code)
    return { success: code === 3, stateCode: code }
  }

  return { configureWifi, requireAuthorized }
}