text: // Copyright (c) 2011-2014 The Bitcoin developers
  // Copyright (c) 2014-2015 The Dash developers
  // Copyright (c) 2015-2017 The PIVX developers
  // Copyright (c) 2018-2019 The esbcoin Core developers
  // Distributed under the MIT/X11 software license, see the accompanying
  // file COPYING or http://www.opensource.org/licenses/mit-license.php.
  
  #include "bitcoinaddressvalidator.h"
  
  #include "base58.h"
  
  /* Base58 characters are:
       "123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz"
  
    This is:
    - All numbers except for '0'
    - All upper-case letters except for 'I' and 'O'
    - All lower-case letters except for 'l'
  */
  
  BitcoinAddressEntryValidator::BitcoinAddressEntryValidator(QObject* parent) : QValidator(parent)
  {
  }
  
  QValidator::State BitcoinAddressEntryValidator::validate(QString& input, int& pos) const
  {
      Q_UNUSED(pos);
  
      // Empty address is "intermediate" input
      if (input.isEmpty())
          return QValidator::Intermediate;
  
      // Correction
      for (int idx = 0; idx < input.size();) {
          bool removeChar = false;
          QChar ch = input.at(idx);
          // Corrections made are very conservative on purpose, to avoid
          // users unexpectedly getting away with typos that would normally
          // be detected, and thus sending to the wrong address.
          switch (ch.unicode()) {
          // Qt categorizes these as "Other_Format" not "Separator_Space"
          case 0x200B: // ZERO WIDTH SPACE
          case 0xFEFF: // ZERO WIDTH NO-BREAK SPACE
              removeChar = true;
              break;
          default:
              break;
          }
  
          // Remove whitespace
          if (ch.isSpace())
              removeChar = true;
  
          // To next character
          if (removeChar)
              input.remove(idx, 1);
          else
              ++idx;
      }
  
      // Validation
      QValidator::State state = QValidator::Acceptable;
      for (int idx = 0; idx < input.size(); ++idx) {
          int ch = input.at(idx).unicode();
  
          if (((ch >= '0' && ch <= '9') ||
                  (ch >= 'a' && ch <= 'z') ||
                  (ch >= 'A' && ch <= 'Z')) &&
              ch != 'l' && ch != 'I' && ch != '0' && ch != 'O') {
              // Alphanumeric and not a 'forbidden' character
          } else {
              state = QValidator::Invalid;
          }
      }
  
      return state;
  }
  
  BitcoinAddressCheckValidator::BitcoinAddressCheckValidator(QObject* parent) : QValidator(parent)
  {
  }
  
  QValidator::State BitcoinAddressCheckValidator::validate(QString& input, int& pos) const
  {
      Q_UNUSED(pos);
      // Validate the passed esbcoin address
      CBitcoinAddress addr(input.toStdString());
      if (addr.IsValid())
          return QValidator::Acceptable;
  
      return QValidator::Invalid;
  }
  