package com.github.davidmoten.rx.jdbc;
   
   import java.util.ArrayList;
   import java.util.List;
   
   public class NamedParameters {
   
       public static final JdbcQuery parse(String namedSql) {
           // was originally using regular expressions, but they didn't work well
          // for ignoring parameter-like strings inside quotes.
          List<String> names = new ArrayList<String>();
          int length = namedSql.length();
          StringBuffer parsedQuery = new StringBuffer(length);
          boolean inSingleQuote = false;
          boolean inDoubleQuote = false;
          for (int i = 0; i < length; i++) {
              char c = namedSql.charAt(i);
              if (inSingleQuote) {
                  if (c == '\'') {
                      inSingleQuote = false;
                  }
              } else if (inDoubleQuote) {
                  if (c == '"') {
                      inDoubleQuote = false;
                  }
              } else {
                  if (c == '\'') {
                      inSingleQuote = true;
                  } else if (c == '"') {
                      inDoubleQuote = true;
                  } else if (c == ':' && i + 1 < length
                          && Character.isJavaIdentifierStart(namedSql.charAt(i + 1))) {
                      int j = i + 2;
                      while (j < length && Character.isJavaIdentifierPart(namedSql.charAt(j))) {
                          j++;
                      }
                      String name = namedSql.substring(i + 1, j);
                      c = '?'; // replace the parameter with a question mark
                      i += name.length(); // skip past the end if the parameter
                      names.add(name);
                  }
              }
              parsedQuery.append(c);
          }
          return new JdbcQuery(parsedQuery.toString(), names);
      }
      
      public static class JdbcQuery {
          private final String sql;
          private List<String> names;
  
          public JdbcQuery(String sql, List<String> names) {
              this.sql = sql;
              this.names = names;;
          }
  
          public String sql() {
              return sql;
          }
  
          public List<String> names() {
              return names;
          }
          
  
      }
  
  }