import { asn1, pki } from "node-forge";
import { GlobalMethods } from "./GlobalMethods";
import ERROR_GENERAL_ERROR from "./errors/ERROR_GENERAL_ERROR";
export class PrivateKey {
  private readonly asn1Object: asn1.Asn1;
  private readonly encryptedPrivateKeyValidator = {
    tagClass: asn1.Class.UNIVERSAL,
    type: asn1.Type.SEQUENCE,
    constructed: true,
    value: [
      {
        tagClass: asn1.Class.UNIVERSAL,
        type: asn1.Type.SEQUENCE,
        constructed: true,
        value: [
          {
            tagClass: asn1.Class.UNIVERSAL,
            type: asn1.Type.OID,
            constructed: false,
          },
          {
            tagClass: asn1.Class.UNIVERSAL,
            type: asn1.Type.SEQUENCE,
            constructed: true,
            value: [
              {
                tagClass: asn1.Class.UNIVERSAL,
                type: asn1.Type.SEQUENCE,
                constructed: true,
                value: [
                  {
                    tagClass: asn1.Class.UNIVERSAL,
                    type: asn1.Type.OID,
                    constructed: false,
                  },

                  {
                    tagClass: asn1.Class.UNIVERSAL,
                    type: asn1.Type.SEQUENCE,
                    constructed: true,
                    value: [
                      {
                        tagClass: asn1.Class.UNIVERSAL,
                        type: asn1.Type.OCTETSTRING,
                        constructed: false,
                      },
                      {
                        tagClass: asn1.Class.UNIVERSAL,
                        type: asn1.Type.INTEGER,
                        constructed: false,
                      },
                    ],
                  },
                ],
              },
              {
                tagClass: asn1.Class.UNIVERSAL,
                type: asn1.Type.SEQUENCE,
                constructed: true,
                value: [
                  {
                    tagClass: asn1.Class.UNIVERSAL,
                    type: asn1.Type.OID,
                    constructed: false,
                  },
                  {
                    tagClass: asn1.Class.UNIVERSAL,
                    type: asn1.Type.OCTETSTRING,
                    constructed: false,
                  },
                ],
              },
            ],
          },
        ],
      },
      {
        // encryptedData
        tagClass: asn1.Class.UNIVERSAL,
        type: asn1.Type.OCTETSTRING,
        constructed: false,
      },
    ],
  };

  constructor(x509Binary: string) {
    this.asn1Object = GlobalMethods.readASN1(x509Binary);
    let errors: Array<string> = [];
    // @ts-ignore
    const isEncrypted = asn1["validate"](
      this.asn1Object,
      this.encryptedPrivateKeyValidator,
      null,
      errors,
    );
    if (!isEncrypted) {
      const message = `Llave privada no válida \n${errors.join("\n")}`;
      throw new ERROR_GENERAL_ERROR(message);
    }
  }

  rsaDecrypt(encryptedText: string, passwordKey: string) {
    const privateKeyInfo = pki.decryptPrivateKeyInfo(
      this.asn1Object,
      passwordKey,
    );
    const pem = pki.privateKeyInfoToPem(privateKeyInfo);
    const privateKey = pki.privateKeyFromPem(pem);
    const plainText = privateKey.decrypt(encryptedText);
    return plainText;
  }

  rsaSign(message: string, passwordKey: string, encoding?: "utf8") {
    const privateKeyInfo = pki.decryptPrivateKeyInfo(
      this.asn1Object,
      passwordKey,
    );
    const pem = pki.privateKeyInfoToPem(privateKeyInfo);
    const privateKey = pki.privateKeyFromPem(pem);
    const messageHash = GlobalMethods.hash(message, "sha256", true, encoding);
    console.log("mnessageHash", messageHash);
    const signature = privateKey.sign(messageHash);
    return signature;
  }
}