#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#define TRUE 1
#define FALSE 0

int main(void)
{
    int selection;
    srand(time(NULL));

    printf("~~ FAST FOOD RESTARAUNT SIMULATION ~~\n\nPress 1 to initialize scenario 1. \nPress 2 to initialize scenario 2. \nAny other key will exit the program.\n\nSelection: ");
    scanf("%d",&selection);

    switch(selection)
    {
        case 1:
            scenarioOne();
            break;
        case 2:
            scenarioTwo();
            break;
        default:
            break;
    }
return 0;
}

int scenarioOne(void)
{
    printf("SCENARIO ONE CHOSEN.\n\n");

/// USER DEFINES CUSTOMERS PER MINUTE
    double r;
    printf("Define the arrival rate of customers per minute: ");
    scanf("%lf",&r);

/// CUSTOMERS PER SECOND
    double customerArrive; // the chance a customer will arrive at any given second
    customerArrive=(r*1.0)/60;
    printf("Theoretically, there will be %f customers arriving per second.\n Press 'Enter' to continue.\n",customerArrive);

        getchar();
        getchar();

/// EACH ITERATION IS A 10-MINUTE INTERVAL
// THIS IS WRONG. TWO FOR-LOOPS CANNOT MAKE TIME A CONTINUOUS FUNCTION...
    int i;
    for (i=0; i<18; i++)
        interval(customerArrive);
}

int interval(double customerArrive)
{
        // Counter to determine which interval is currently running.
        static int intNum;
        intNum++;
        printf("---------------------------INTERVAL %d------------------------\n\n",intNum);

        int totalCustomer=0; // total # of customers
        int completedOrder=0; // total # of completed orders

        int totalOrderWait=0; // total wait time for ORDERS
        int totalDelayWait=0; // total wait time for DELAYS
        int avgWait=0; // AVERAGE wait time

        int delay1=0; // delay time
        int delay2=0; // delay time

        int queue=0; // customer queue count

        int cash1empty=1; // whether or not a customer can get served by cash 1
        int cash2empty=1; // whether or not a customer can get served by cash 2

        int cash1salad,cash1burger,cash2salad,cash2burger; // different types of orders

        /// EACH ITERATION IS ONE SECOND
            int t;
            for (t=0;t<600;t++)
            {
                /// Generate random value between 0 and 1. Used as a decimal to compare to chance of customer arrival
                double x;
                x= (double) rand() / (double) RAND_MAX;

                if (customerArrive>=x)
                {
                    // A customer arrived during this second!
                    totalCustomer++;
                    queue++;

                }
                if (queue > 0)
                {

                    // In the case that both cashiers are empty, the program must decide where the customer goes with a coin toss
                    if ((cash1empty==TRUE)&&(cash2empty==TRUE))
                    {
                        switch((rand()%2))
                        {
                            case 0:
                                cash2empty=FALSE;
                                break;
                            case 1:
                                cash1empty=FALSE;
                                break;
                        }
                    }
                    if (delay1>0)
                    {
                        delay1--;
                        totalDelayWait++;
                        cash1empty=FALSE;
                    }
                    else
                        cash1empty=TRUE;

                    if (cash1empty==TRUE)
                    {
                        cash1empty=FALSE;
                        queue--;
                        printf("Cash 1 is being used.\n");


                        switch((rand()%2))
                        {
                            case 0:
                                cash1salad=(rand()%(66-55)+55);
                                printf("At t=%d, salad order took %d seconds at Cash 1.\n\n",t,cash1salad);
                                delay1=cash1salad;
                                totalOrderWait+=cash1salad;
                                completedOrder++;

                                break;
                            case 1:
                                cash1burger=(rand()%(131-111)+111);
                                printf("At t=%d, burger order took %d seconds at Cash 1.\n\n",t,cash1burger);
                                delay1=cash1burger;
                                totalOrderWait+=cash1burger;
                                completedOrder++;
                                break;
                        }
                    }

                    else if (cash2empty==TRUE)
                    {
                        cash2empty=FALSE;
                        queue--;
                        printf("Cash 2 is being used.\n");


                        switch(rand()%2)
                        {
                            case 0:
                                cash2salad=(rand()%(76-65)+65);
                                printf("At t=%d, salad order took %d seconds at Cash 2.\n\n",t,cash2salad);
                                delay2=cash2salad;
                                totalOrderWait+=cash2salad;
                                completedOrder++;
                                break;
                            case 1:
                                cash2burger=(rand()%(141-121)+121);
                                printf("At t=%d, burger order took %d seconds at Cash 2. \n\n",t,cash2burger);
                                delay2=cash2burger;
                                totalOrderWait+=cash2burger;
                                completedOrder++;
                                break;
                        }
                    }
                }
            }

            // customer arrival rate per minute, by probability
            double R;
            R=(totalCustomer*1.0)/600;
            printf("Customers arriving per minute in interval %d: %f\n",intNum,R);
            if (completedOrder>0)
            {
                avgWait=((totalOrderWait+totalDelayWait)/(completedOrder));

                printf("Amount of customers that showed up: %d\n",totalCustomer);
                printf("Amount of customers that had their order completed: %d\n",completedOrder);

                printf("In total, %d seconds were spent by people lining up.\n",totalDelayWait);
                printf("In total, %d seconds were spent by people taking orders.\n",totalOrderWait);

                    if (avgWait>=0)
                    {
                        printf("Average wait time per customer: %d\n\n",avgWait);
                    }
            }
            else
            {
                printf("No customers arrived in this interval.\n\n");
            }
            printf("-----------------------END OF INTERVAL %d---------------------\n\n",intNum);

}

int scenarioTwo(void)
{
    printf("SCENARIO TWO CHOSEN.\n\n");
    // scenario two is not yet programmed...
}