#include "CityGrouper.h"

CityGrouper::CityGrouper(string InputFileName)
{
		
	ifstream istream;
	
	string line, city, country;
	int pos;

	istream.open(InputFileName.c_str(), ios_base::in);


	if(!istream)
	{
		cout << "Error opening file: " << InputFileName << endl;
		system("pause");
		exit(0);
	}

	while (!istream.eof())
	{
		//get string
		getline(istream, line);
		
		//split string
		pos = line.find(',');
		city = line.substr(0, pos);
		country = line.substr(pos+2);

		//store string
		country2city.insert( make_pair(country, city) );
		
		//check to see if country is already in keys
		set<string>::iterator key = countries.find(country);

		//Didn't find the country(key) in keys
		if (key == countries.end())
		{
			//add it
			countries.insert(country);
		}


	}
	istream.close();
}


void CityGrouper::GroupCitiesByCountry(void)
{
	set<string>::iterator keyIt;
	for (keyIt = countries.begin(); keyIt != countries.end(); ++keyIt)
	{
		pair<hash_multimap<string,string>::iterator, hash_multimap<string,string>::iterator> itPair;
		hash_multimap<string,string>::iterator it;


		//get equal range of each country 
		itPair = country2city.equal_range(*keyIt);
		
		cout << itPair.first->first << endl << endl;
		for(it = itPair.first; it != itPair.second; ++it)
		{
			cout << "\t" << it->second << endl;
		}
		cout << endl;
	}
}