//
// Graphs
//

#include <iostream>
#include <string>
#include <fstream>

using namespace std ;

#include "Graph.h"

void Insert(Graph & gr) ;
void Dijkstra(Graph & gr) ;
char GetMenuChoice(void) ;

int main(int argc, char * argv[]){
    Graph gr ;
    char menuChoice = GetMenuChoice() ;

    while(menuChoice != 'X')
    {
	if(menuChoice == '1')
		Insert(gr) ;
	else if(menuChoice == '2')
		Dijkstra(gr) ; 
	else
	    cout << "Invalid Menu Choice." << endl ;
	menuChoice = GetMenuChoice() ;
    }

    cout << "Goodbye!" << endl ;

    return 0 ;
}

// Function Definitions
// Pre - None
// Post - Displays the Menu & Gets the user's choice & Returns it
char GetMenuChoice(void)
{
    char menuChoice[500] ;
    
    do
    {
	cout << "--------------------" << endl ;
	cout << "Homework 6 MAIN MENU" << endl ;
	cout << "--------------------" << endl ;
	cout << "1 - Insert Cities and Roads from File" << endl ;
	cout << "2 - Shortest Path, Dijkstras Algorithm" << endl ;
	cout << "X - EXIT PROGRAM" << endl ;
	cout << "--------------------" << endl ;
	cout << "Choose an Option (hit enter): " ;
	cin.getline(menuChoice, 499) ;
    }while(strlen(menuChoice) != 1) ;
    return toupper(menuChoice[0]) ;
}


void Insert(Graph & gr)
{
	string filename ;
	cout << "Enter a filename: " ;
	cin >> filename ;
	cin.get() ;

	ifstream in ;
	in.open(filename.c_str(), ios::in) ;
	int numCities = 0 ;
	in >> numCities ;
	int counter = 0 ;
	while(counter < numCities)
	{
		string city ;
		in >> city ;

		gr.InsertCity(city) ;

		// debug
		cout << "read from file : " << city << endl ;
		counter++ ;
	}

	int numRoads = 0 ;
	in >> numRoads ;
	counter = 0 ;
	while(counter < numRoads)
	{
		string city1 ;
		string city2 ;
		int distance ;
		in >> city1 ;
		in >> city2 ;
		in >> distance ;

		gr.InsertRoad(city1, city2, distance) ;

		// debug
		cout << "read from file : " << city1 << " to " << city2 << " is " << distance << endl ;
		counter++ ;
	}

	in.close() ;
}

void Dijkstra(Graph & gr) 
{
	string City1 ;
	string City2 ;
	cout << "Enter City 1: " ;
	cin >> City1 ;
	cout << "Enter City 2: " ;
	cin >> City2 ;
	cin.get() ;

	cout << "Dijkstra's Algorithm says shortest distance is : " << gr.Dijkstra(City1, City2) << endl ; 
	
}