#include <stdio.h>
#include <stdlib.h>

/*******************************************************************************
*
* Program: Read CSV File Data To An Array Of Structs
*
* Description: Example of reading CSV file data into an array of structs in C.
*
* YouTube Lesson: https://www.youtube.com/watch?v=rbVt5v8NNe8
*
* Author: Kevin Browne @ https://portfoliocourses.com
* 
*// https://github.com/portfoliocourses/c-example-code/blob/main/csv_to_struct_array.c
*******************************************************************************/



typedef struct
{
    // members for the student's type, name, age and average
    char type [5];
    char name[50];
    int age;
    double average;

} Student;

// total number of students stored in the array of structs
#define TOTAL_STUDENTS 6

int main() {

    // file pointer variable for accessing the file
    FILE *file;

    // Attempt to open the file file.csv for writing, if the file does not exist
    // it will be created and if it does any existing content will be erased
    // before we begin to write to the file.
    file = fopen("Students.csv", "w");

    // If the call to fopen() above is successful it will return a file pointer
    // we can use to write to the file, and if it fails it will return NULL.  So
    // if file is set to NULL we know there has been an error opening the file,
    // and we exit with an error message and status.
    if (file == NULL)
    {
        printf("Error opening file.\n");
        return 1;
    }

    int TotalStudents;
    printf("no. of students\n");
    scanf("%d", &TotalStudents);

    Student *student;
    student = malloc(sizeof( student) * TotalStudents);

    int i;
    printf("\nstudents information:\n\n");
    https://stackoverflow.com/questions/22344953/how-to-use-malloc-or-new-in-struct
    for (i = 0; i < TotalStudents; ++i) {
        printf("enter the type:");
        scanf(" %s", student[i].type);
        printf("enter the name:");
        scanf("%s", student[i].name);
        printf("enter age:");
        scanf("%d", &student[i].age);
        printf("enter the average:");
        scanf("%lf", &student[i].average);
    }
    for (int i = 0; i < TotalStudents; i++)
    {
        // Output to the file a line of comma separated values for the current
        // Student struct.  The placeholders %c %s %d and %.2f are used to output
        // a char, a string, an int and a double respectively for the members/fields
        // type, name, age and average.  The %.2f is used to output the average
        // with two decimal digits of accuracy.

        //fprintf(file,"type, Name      ,age, average\n");
        fprintf(file,
                "%-5s,%-10s,%-3d,%.2f\n",
                student[i].type,
                student[i].name,
                student[i].age,
                student[i].average);

        // If there is an error writing to the file we identify that it has
        // occurred using ferror(file) and exit with an error message and status
        // if so.
        if (ferror(file))
        {
            printf("Error writing to file.\n");
            return 1;
        }
    }

    // close the file since we are done working with it
    fclose(file);
    // output the total number of records written to the file
    printf("\n%d records written.\n\n", TotalStudents);


    // free memory when you are not using this.
    free(student)

            ;
    // student5 isnull
    student = NULL

            ;
    return 0;
}