//  To compile this in the CLAMV computers simply write "g++ -o Nagel-Schreckenberg_TrafficModel Nagel-Schreckenberg_TrafficModel.cpp"
//
//  main.cpp
//  trafficflow
//
//  Created by Alexandru Mihai on 10/19/14.
//  Copyright (c) 2014 JacobsUniversity. All rights reserved.
//

#include <iostream>
#include <cmath>
#include <fstream>

using namespace std;

int street1[100];
int street2[100];

//Here a random starting point is chosen for the 6 car traffic jam
int r = arc4random()%100;
int trafficjam[6] = {r,r+1,r+2,r+3,r+4,r+5};

//Here the dawdle probability is given
int probability = 250;

//This function give the starting points of the cars using a recursive function based on a random number generator, to ensure that the traffic jam is not overwritten
int initializing()
{
    int position = (arc4random() % 100);
    
    if (position == trafficjam[0] || position == trafficjam[1] || position == trafficjam[2] || position == trafficjam[3] || position == trafficjam[4] || position == trafficjam[5])
    {
        return initializing();
    }
    else
    {
        return position;
    }
}

// This function is the one that assigns the random initial velocities to the starting points using the previous function.
void startingpositions()
{
    street1[trafficjam[5]] = (arc4random() % 4) + 3;
    for( int k = 0; k < 5; k++)
    {
        street1[trafficjam[k]] = 1;
    }
    for( int i = 1; i < 25; i++)
    {
        street1[initializing()] = (arc4random() % 6) + 1;
    }
}

// This is the collision step, meaning the step in which the cars change the velocity with with they are traveling(excluding the dawdle prob.)
// Within teach larger If loop is a check that the max velocity is not surpassing the space the car has to move, therby ensuring nu accidents
void collision_step()
{
    for(int k=0;k<100;k++){street2[k] = 0;}
    
    for( int j = 0; j < 100; j++)
    {
        if(street1[j] == 6)
        {
            if(street1[(j+1)%100] != 0)
            {
                street2[j] = 1;
            }
            else if(street1[(j+2)%100] != 0)
            {
                street2[j] = 2;
            }
            else if(street1[(j+3)%100] != 0)
            {
                street2[j] = 3;
            }
            else if(street1[(j+4)%100] != 0)
            {
                street2[j] = 4;
            }
            else if(street1[(j+5)%100] != 0)
            {
                street2[j] = 5;
            }
            else
            {
                street2[j] = 6;
            }
        }
        
        if(street1[j] == 5)
        {
            if(street1[(j+1)%100] != 0)
            {
                street2[j] = 1;
            }
            else if(street1[(j+2)%100] != 0)
            {
                street2[j] = 2;
            }
            else if(street1[(j+3)%100] != 0)
            {
                street2[j] = 3;
            }
            else if(street1[(j+4)%100] != 0)
            {
                street2[j] = 4;
            }
            else if(street1[(j+5)%100] != 0)
            {
                street2[j] = 5;
            }
            else
            {
                street2[j] = 6;
            }
        }
        
        if(street1[j] == 4)
        {
            if(street1[(j+1)%100] != 0)
            {
                street2[j] = 1;
            }
            else if(street1[(j+2)%100] != 0)
            {
                street2[j] = 2;
            }
            else if(street1[(j+3)%100] != 0)
            {
                street2[j] = 3;
            }
            else if(street1[(j+4)%100] != 0)
            {
                street2[j] = 4;
            }
            else
            {
                street2[j] = 5;
            }
        }
        
        if(street1[j] == 3)
        {
            if(street1[(j+1)%100] != 0)
            {
                street2[j] = 1;
            }
            else if(street1[(j+2)%100] != 0)
            {
                street2[j] = 2;
            }
            else if(street1[(j+3)%100] != 0)
            {
                street2[j] = 3;
            }
            else
            {
                street2[j] = 4;
            }
        }
        
        if(street1[j] == 2)
        {
            if(street1[(j+1)%100] != 0)
            {
                street2[j] = 1;
            }
            else if(street1[(j+2)%100] != 0)
            {
                street2[j] = 2;
            }
            else
            {
                street2[j] = 3;
            }
        }
      
        if(street1[j] == 1)
        {
            if(street1[(j+1)%100] != 0)
            {
                street2[j] = 1;
            }
            else
            {
                street2[j] = 2;
            }
        }

        if(street2[j] == 0)
        {
            street2[j] = 0;
        }
        
    }
}

// In this function the dawdle probability of called and changes the velocities of the respective cars
void dawdle()
{
    for( int j = 0; j < 100; j++)
    {
        if(street2[j] == 2)
        {
            if(arc4random()%1000 < probability)
            {
                street2[j] = 1;
            }
            else
            {
                street2[j] = 2;
            }
        }
        if(street2[j] == 3)
        {
            if(arc4random()%1000 < probability)
            {
                street2[j] = 2;
            }
            else
            {
                street2[j] = 3;
            }
        }
        
        if(street2[j] == 4)
        {
            if(arc4random()%1000 < probability)
            {
                street2[j] = 3;
            }
            else
            {
                street2[j] = 4;
            }
        }
        
        if(street2[j] == 5)
        {
            if(arc4random()%1000 < probability)
            {
                street2[j] = 4;
            }
            else
            {
                street2[j] = 5;
            }
        }
        
        if(street2[j] == 6)
        {
            if(arc4random()%1000 < probability)
            {
                street2[j] = 5;
            }
            else
            {
                street2[j] = 6;
            }
        }
    }
}

// In the stream_step function we propegate the velocities we calculated in the collision function so that the iteration can continue
void stream_step()
{
    for(int k=0;k<100;k++){street1[k] = 0;}
    
    for( int j = 0; j < 100; j++)
    {
        //street1[j] = 0;
        
        if(street2[j] == 6)
        {
            street1[(j+5)%100] = 6;
        }
        
        if(street2[j] == 5)
        {
            street1[(j+4)%100] = 5;
        }
        
        if(street2[j] == 4)
        {
            street1[(j+3)%100] = 4;
        }
        
        if(street2[j] == 3)
        {
            street1[(j+2)%100] = 3;
        }
        
        if(street2[j] == 2)
        {
            street1[(j+1)%100] = 2;
        }
        
        if(street2[j] == 1)
        {
            street1[j] = 1;
        }
    }
}

// And here the final iteration with respect to time takes place, putting together all of the previous functions.
void iteration( int iter, ostream& output)
{
    startingpositions();
    for(int t = 0; t < iter; t++)
    {
        for( int k = 0; k < 100; k++)
        {
            if(street1[k] != 0)
            {
                street1[k] = 1;
            }
            else
            {
                street1[k] = 0;
            }
            output << street1[k];
        }
        output << "\n";
        
        collision_step();
        if(probability != 0)
        {
            dawdle();
        }
        stream_step();
    }
}
int main()
{
    ofstream myFileStream("street3");
    iteration(500,myFileStream);
    myFileStream.close();

    return 0;
}