/* This is the main portion of the RSVP program, by Christopher Aden <cbaden@ucdavis.edu>.
 * All output is handled in this file. The file takes in function
 * prototypes from vector.h, course.h, and student.h, and the functions written
 * in their corresponding c files. The main will read into two structures: a student struc and a course struc.
 * The read in file is specified by the user with a command line argument.
 * The user is then presented with the menu of options, asking if they want to find a CRN
 * or subject, which sends them to a corresponding function. They are also given the ability to
 * add or remove classes from a user using a student ID. */

#include <stdio.h>
#include "vector.h"
#include "course.h"

//This function prompts the user for their RSVP choice. Their choice is assigned as an int and returned.
int get_choice()
{
    int entry;
    printf("\n");
    printf("RSVP Menu\n");
    printf("0. Done.\n");
    printf("1. Find by CRN.\n");
    printf("2. Find by subject.\n");
    printf("3. Add course.\n");
    printf("4. Remove course.\n");
    printf("Your choice (0 - 4): ");
    scanf("%d", &entry);
    return entry;
}

//Function takes in courses struc, student struc, and associated array sizes.
//It will then enter a loop where it calls get_choice and gets an int value for the variable entry.
//If entry is zero, the loop breaks. An entry value of 1 finds a CRN, 2 finds a subject, 3 adds a course to a student,
// and 4 will remove a course. If neither 0, 1, 2, 3, nor 4 are entered, the choice is outside the range and the loop continues.
void display_info(courseStruct * courses, studentStruct * students, int courseArraySize, int studentArraySize)
{
    int entry=5;
    while (1)
    {
        entry = get_choice();
        if (entry == 0)
            break;
        else if (entry == 1)
            find_CRN(courses, students, courseArraySize, studentArraySize);
        else if (entry == 2)
            find_subject(courses, courseArraySize);
        else if (entry == 3)
            add_course(courses, &students, courseArraySize, studentArraySize);
        else if (entry == 4)
            remove_course(courses, &students, courseArraySize, studentArraySize);
        else
            printf("Your choice is outside the acceptable range.  Please try again.\n");
    }

}

//Main declares the course and student structures, and starting memory size ints.
//It then reads in the source course list from command line argument 1 with the function
//read_courses (written in course.c). Once the information is correctly entered into the strucs,
//the user is presented with a main menu and chooses what they'd like to do.
int main(int argc, char ** argv)
{
    courseStruct * courses; studentStruct * students;
    int courseArraySize = COURSE_ARRAY_SIZE, studentArraySize = STUDENT_ARRAY_SIZE;
    read_courses(argv[1], &courses, &courseArraySize);
    read_students(argv[2], &students, &studentArraySize);
    display_info(courses, students, courseArraySize, studentArraySize);
    return (0);
}