#include <iostream>
#include "ListReader.h"
#include "SortedList.h"
#include "Node.h"

using namespace std;

istream*  ListReader::isr = &cin;
bool ListReader::eof = false;
int ListReader::lineLimit = -1;
int ListReader::lineCount = 0;


void ListReader::buildList(SortedList& list) {

  if (eof || (lineLimit!=-1 && lineCount>=lineLimit)) {
    throw 0;
  }

  list.header = new Node(random()%200-500,NULL,NULL);
  list.trailer = new Node(random()%200-500,NULL,NULL);
  list.header->next = list.trailer;
  list.trailer->prev = list.header;

  NodePtr current = list.header;
  cout << "Enter a list...\n";

  int value;
  int last=-1;
  (*isr) >> value;
  while (true) {

    lineCount++;

    if ((*isr).eof()) {
      // must be EOF
      if (isr != &cin) {
	// switch from file to cin
	isr = &cin;
	continue;
      } else {
	cout << "Unexpected end of input reached.\n";
	throw 0;
      }
    }


    if (!(*isr)) {
      // non-numeric input
      (*isr).clear();	
      (*isr).ignore(numeric_limits<streamsize>::max(),'\n');
      cout << "error on input line " << lineCount << ". Non-numeric data ignored.\n";
    } else if (value<0 || value > 999) {
      if (value==-1) {
	eof = true;
	break;
      }

      if (value==1000)
	break;

      // invalid
      cout << "error on input line " << lineCount << ". Invalid value " << value << " ignored.\n";
    } else {
      if (value < last) {
	// decreasing
      cout << "error on input line " << lineCount << ". Decreasing value " << value << " ignored.\n";
      } else {
	// valid
	last = value;
	NodePtr v = new Node(value,current,current->next);
	v->next->prev = v;
	v->prev->next = v;
	current = v;
      }
    }

    if (lineLimit!=-1 && lineCount>=lineLimit) {
      break;
    }

    (*isr) >> value;
  }

  if (lineLimit!=-1 && lineCount>=lineLimit) {
    cout << "ListReader reached the limit of "<< lineLimit << " lines of input.\n";
  }

}