//===================================================================
// Matt Kretchmar
// A simple program illustrating
// - nested structs
// - malloc and free
// - tokenizer with strtok
//===================================================================

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

typedef struct exam_t
{
    float grade;
    float bonuspoints;
} Exam_T;

typedef struct homework_t
{
    int score;
    struct homework_t *next;
} Homework_T;

typedef struct student_t
{
    char name[20];
    Exam_T *exams;
    Homework_T *homeworks;
} Student_T;

int main ( int argc, char *argv[] )
{

    int i,j,n;
    char *filename;
    if ( argc >= 2 ) filename = argv[1];
    else             filename = "students.txt";
    
    // Open the data file for reading
    FILE *fp = fopen(filename,"r");
    if ( !fp )
    {
        printf("Error opening file [%s]\n",filename);
        exit(1);
    }

    // Read n from file.  Create an array of n students.
    Student_T *class;
    fscanf(fp,"%d\n",&n);
    class = (Student_T *) malloc ( sizeof(Student_T) * n );
    
    // read the set of 3 exams for each student
    char buffer[200];
    for (i = 0; i < n; i++ )
    {
        fgets(buffer,200,fp);
        printf("Processing student %d: %s\n",i,buffer);
        char *s = strtok(buffer," \t\n");
        strcpy(class[i].name,s);
        printf("\tName: %s \t",class[i].name);
        class[i].exams = (Exam_T *) malloc (sizeof(Exam_T) * 3);
        for (j = 0; j < 3; j++ )
        {
            char *score = strtok(NULL," \t\n");
            class[i].exams[j].grade = atof(score);
            class[i].exams[j].bonuspoints = 0;
            printf("(%4.1f) \n",class[i].exams[j].grade);
        }
            
    }
    
    // You might have a part here that reads in the variable number
    // of homeworks into a linked list
    
    // free the exam memory
    for (i = 0; i < n; i++ )
    {
        free(class[i].exams);
    }
    
    // free the student array
    free(class);
    
    // close the file
    fclose(fp);
    return 0;
}



/*
 Sample data file below

 2
 Mary   82 70 88       50 77 83 80
 Tom    65 88 92       100 90 56
*/