// CS19, Cabrillo College
// Steve J. Hodges
// ANSII C++ string class example
// tests strings for palindrome-ness

// This example is intended to replace
// the palindrome example program from our textbook
// I believe that program (09-06.cpp) has several flaws including:
//   * lack of use of standard library functions
//   * improper/inadequate/non-standard re-creation of same
//   * poor overall detection algorithm
//     (perhaps easier to understand but at the penalty of doing extra work)

#include <iostream>
#include <string>
#include <cctype>
using std::string;
using std::cin;
using std::cout;
using std::endl;

string transformString(const string& s);
bool isPalindrome(const string& s);


// generate a string without punctuation
// or whitespace
// and all lowercase characters
// by appending all non-punct characters 
// to a new string
string transformString(const string& s){
  string fixed=""; //initially empty
  char c; // a character to examine
  int sLength = s.length( );
  for (int i = 0; i < sLength; i++){
    c = s.at(i);
    if (!ispunct(c) && !isspace(c))
      fixed += tolower(c);
  }
  return fixed;
}

//uses function transformString
// compare first half of transformed string
// to last half (in reverse)
bool isPalindrome(const string& s){
  string str=transformString(s);
  int len = str.length();
  int half = len/2;
  for (int i=0; i< half; i++){
    if (str.at(i) != str.at(len-1-i))
      return false;
  }
  return true;
}



int main( ){
  string str;
  cout << "Enter a candidate for palindrome test\n:";
  getline(cin, str);
  
  if (isPalindrome(str))
    cout << "is a palindrome.";
  else
    cout << "is not a palindrome.";

  cout << endl;
  return 0;
}