import { cryptoFramework } from '@kit.CryptoArchitectureKit';
import { buffer, util } from '@kit.ArkTS';


export const base = new util.Base64Helper();

const kBase64EncodeChars = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
const kBase64PaddingChar = '=';

export class AESEncryptionDecryption {

  // 字节流转成可理解的字符串
  static uint8ArrayToString(array: Uint8Array) {
    // 将UTF-8编码转换成Unicode编码
    let out: string = '';
    let index: number = 0;
    let len: number = array.length;
    while (index < len) {
      let character = array[index++];
      switch (character >> 4) {
        case 0:
        case 1:
        case 2:
        case 3:
        case 4:
        case 5:
        case 6:
        case 7:
          out += String.fromCharCode(character);
          break;
        case 12:
        case 13:
          out += String.fromCharCode(((character & 0x1F) << 6) | (array[index++] & 0x3F));
          break;
        case 14:
          out += String.fromCharCode(((character & 0x0F) << 12) | ((array[index++] & 0x3F) << 6) |
            ((array[index++] & 0x3F) << 0));
          break;
        default:
          break;
      }
    }
    return out;
  }

  // 字符串转成字节流
  static stringToUint8Array(str: string) {
    return new Uint8Array(buffer.from(str, 'utf-8').buffer);
  }

  // 获取密钥
  static async  getKey() {
    let symAlgName = 'AES128';
    let symKeyGenerator = cryptoFramework.createSymKeyGenerator(symAlgName);
    let dataUint8Array = AESEncryptionDecryption.stringToUint8Array('Whh82GtW/EVjBkD8');
    let keyBlob: cryptoFramework.DataBlob = { data: dataUint8Array };
    let promiseSymKey = await symKeyGenerator.convertKey(keyBlob);
    let key = base.encodeToStringSync(promiseSymKey.getEncoded().data); // 将密钥转换为base64存储
    return key;
  }

  // 加密
  static async aesEncrypt(text: string, puKey: string): Promise<string> {
    let globalResult = '';
    try {
      let cipherAlgName = 'AES128|ECB|PKCS7';
      let globalCipher = cryptoFramework.createCipher(cipherAlgName);
      let symAlgName = 'AES128';
      let symKeyGenerator = cryptoFramework.createSymKeyGenerator(symAlgName);
      // let dataUint8Array = base.decodeSync(puKey);
      let dataUint8Array = AESEncryptionDecryption.stringToUint8Array(puKey);
      let keyBlob: cryptoFramework.DataBlob = { data: dataUint8Array };
      let promiseSymKey = await symKeyGenerator.convertKey(keyBlob);
      await globalCipher.init(cryptoFramework.CryptoMode.ENCRYPT_MODE, promiseSymKey, null);
      let result = await globalCipher.doFinal({ data: AESEncryptionDecryption.stringToUint8Array(text) });
      globalResult = base.encodeToStringSync(result.data);
      console.info('加密后的明文:' + globalResult);
    } catch (err) {
      console.info('加密错误:' +err.message);
    }
    return globalResult;
  }
  // 使用 AES 密钥加密数据

  static encryptMessage(symKey: cryptoFramework.SymKey, plainText: cryptoFramework.DataBlob) {

    let cipher = cryptoFramework.createCipher('AES128|ECB|PKCS7');

    cipher.initSync(cryptoFramework.CryptoMode.ENCRYPT_MODE, symKey, null); // ECB模式params为null。

    let cipherData = cipher.doFinalSync(plainText);

    return cipherData;

  }

  // 解密
  static async aesDecrypt(text: string, key: string) {
    let globalResult = '';
    try {
      let cipherAlgName = 'AES128|ECB|PKCS7';
      let globalCipher = cryptoFramework.createCipher(cipherAlgName);
      let symAlgName = 'AES128';
      let symKeyGenerator = cryptoFramework.createSymKeyGenerator(symAlgName);
      let dataUint8Array = base.decodeSync(key);
      let keyBlob: cryptoFramework.DataBlob = { data: dataUint8Array };
      let promiseSymKey = await symKeyGenerator.convertKey(keyBlob);
      await globalCipher.init(cryptoFramework.CryptoMode.DECRYPT_MODE, promiseSymKey, null);
      let plainText: cryptoFramework.DataBlob = { data: base.decodeSync(text) };
      let result = await globalCipher.doFinal(plainText);
      globalResult = AESEncryptionDecryption.uint8ArrayToString(result.data);
      console.info('解密后的明文:' + globalResult);
    } catch (err) {
      console.info(err.message);
    }
  }

  // 解密
  static async aes128Decrypt(data: Uint8Array, key: string): Promise<Uint8Array> {
    try {
      // 创建对称密钥生成器
      const symKeyGenerator = cryptoFramework.createSymKeyGenerator('AES128');
      // 创建加密解密工具
      const cipher = cryptoFramework.createCipher('AES128|ECB|PKCS7');
      // 将字符串密钥转换为DataBlob格式
      const keyBlob: cryptoFramework.DataBlob = {
        data: new Uint8Array(new util.TextEncoder().encodeInto(key))
      };
      // 生成对称密钥
      const symKey = await symKeyGenerator.convertKey(keyBlob);
      // 初始化解密模式
      await cipher.init(cryptoFramework.CryptoMode.DECRYPT_MODE, symKey, null);
      // 执行解密
      const decryptData = await cipher.doFinal({ data: data });
      return decryptData.data;
    } catch (error) {
      console.error("AES解密过程中出错:", JSON.stringify(error));
      return data
    }
  }

  //加密
  static async aes128Encrypt(data: Uint8Array, key: string): Promise<Uint8Array> {
    const algorithm = 'AES128|ECB|PKCS7';
    try {
      const symKeyGenerator = cryptoFramework.createSymKeyGenerator('AES128');
      if (!symKeyGenerator) {
        console.error('创建密钥生成器失败')
      }
      const textEncoder = new util.TextEncoder();
      const keyData: Uint8Array = textEncoder.encodeInto(key);
      const keyBlob: cryptoFramework.DataBlob = { data: keyData };
      const symKey = await symKeyGenerator.convertKey(keyBlob);
      if (!symKey) {
        console.error('密钥转换失败')
      }
      const cipher = cryptoFramework.createCipher(algorithm)
      if (!cipher) {
        console.error('创建加密器失败')
      }
      await cipher.init(cryptoFramework.CryptoMode.ENCRYPT_MODE, symKey, null);
      const encryptResult = await cipher.doFinal({ data });
      return encryptResult.data;
    } catch (error) {
      console.error(`AES加密错误: ${JSON.stringify(error)}`);
      const emptyBuffer = new Uint8Array(0);
      return emptyBuffer
    }
  }

  static customBase64Encode(data: Uint8Array): string {
    if (!data || data.length === 0) {
      return "";
    }
    const inputLength = data.length;
    const maxLength = Math.floor((inputLength + 2) / 3) * 4;

    const resultChars: string[] = [];
    let srcIndex = 0;

    while (inputLength - srcIndex >= 3) {
      const byte1 = data[srcIndex++] & 0xFF;
      const byte2 = data[srcIndex++] & 0xFF;
      const byte3 = data[srcIndex++] & 0xFF;

      resultChars.push(kBase64EncodeChars.charAt(byte1 >>> 2));
      resultChars.push(kBase64EncodeChars.charAt(((byte1 & 0x03) << 4) | (byte2 >>> 4)));
      resultChars.push(kBase64EncodeChars.charAt(((byte2 & 0x0F) << 2) | (byte3 >>> 6)));
      resultChars.push(kBase64EncodeChars.charAt(byte3 & 0x3F));
    }

    if (inputLength - srcIndex > 0) {
      const byte1 = data[srcIndex++] & 0xFF;
      resultChars.push(kBase64EncodeChars.charAt(byte1 >>> 2));

      if (inputLength - srcIndex === 0) {
        resultChars.push(kBase64EncodeChars.charAt((byte1 & 0x03) << 4));
        resultChars.push(kBase64PaddingChar);
        resultChars.push(kBase64PaddingChar);
      } else {
        const byte2 = data[srcIndex] & 0xFF;
        resultChars.push(kBase64EncodeChars.charAt(((byte1 & 0x03) << 4) | (byte2 >>> 4)));
        resultChars.push(kBase64EncodeChars.charAt((byte2 & 0x0F) << 2));
        resultChars.push(kBase64PaddingChar);
      }
    }

    return resultChars.join('');
  }
}