// Oldham, Jeffrey D.
// 2000Mar25
// CS1321

// Test the Deque Implementation

#include <iostream>
#include <stdlib.h>		// has EXIT_SUCCESS
#include "deque.h"
#include <assert.h>
#include <string>

int main()
{
  cout << "Hello, world.\n";
  deque dq;
  string prompt =
    "Please enter an operation to perform:\n"
    "q: quit\n"
    "f: return front char\n"
    "Pf<char>: push_front\n"
    "pf: pop_front\n"
    "b: return back char\n"
    "Pb<char>: push_back\n"
    "pb<char>: pop_back\n"
    "a<number>: access <number>'th element\n";
  string reply;
  cout << prompt;
  while (getline(cin, reply)) {
    if (reply.size() > 0) {
      char c = reply[0];
      if (c == 'q' || c == 'Q')
	return EXIT_SUCCESS;
      else if (c == 'P' && reply.size() >= 3) {	// push
	if (tolower(reply[1]) == 'f')
	  dq.push_front(reply[2]);
	else
	  dq.push_back(reply[2]);
      }
      else if (c == 'p' && reply.size() >= 2) {	// pop
	if (tolower(reply[1]) == 'f')
	  dq.pop_front();
	else
	  dq.pop_back();
      }
      else if (c == 'f')
	cout << "The front is " << dq.front() << ".\n";
      else if (c == 'b')
	cout << "The back is " << dq.back() << ".\n";
      else if (c == 'a')
	cout << "The " << reply.substr(1) << "'th element = " <<
	  dq[strtoul(reply.substr(1).c_str(), static_cast<char **>(0),0)] << ".\n";
      else
	cerr << "illegal character " << c << endl;
    }
    cout << dq << endl;
  }

  assert(false);		// impossible to reach here
  return EXIT_FAILURE;
}