import { SM3 } from 'gm-crypto'

// 验证是否为有效的 hex 字符串
const isValidHex = (hex: string): boolean => {
  return /^[0-9a-fA-F]*$/.test(hex) && hex.length % 2 === 0
}

// ArrayBuffer 转 hex 字符串
const arrayBufferToHex = (buffer: ArrayBuffer): string => {
  const bytes = new Uint8Array(buffer)
  return Array.from(bytes).map(byte => byte.toString(16).padStart(2, '0')).join('')
}

// SM3 计算
export const sm3Digest = (message: string): string => {
  try {
    // 验证消息是否为有效的 hex 字符串
    if (!isValidHex(message)) {
      throw new Error('Invalid message: must be hex string')
    }
    
    console.log('Input hex message:', message)
    
    // 直接使用 hex 字符串计算 SM3
    const result = SM3.digest(message, 'hex')
    console.log('SM3 result:', result)
    
    // 处理返回结果
    const hexResult = typeof result === 'string' ? result : arrayBufferToHex(result)
    console.log('Hex result:', hexResult)
    
    return hexResult
  } catch (error) {
    console.error('SM3 digest error:', error)
    throw error
  }
}