// Student rank
// M.Menault 2024

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

void generate_grades(int **students_array, size_t students_number, size_t grades_number) {
    for (size_t i = 0; i < students_number; i++) {
        students_array[i] = malloc(grades_number * sizeof(int));
        generate_array(students_array[i], grades_number);
    }
}

void generate_ranks(int **students_array, size_t students_number, size_t grades_number) {
    for (size_t i = 0; i < students_number; i++) {
        students_array[i] = calloc(grades_number, sizeof(int));
        for (size_t j = 0; j < grades_number; j++) {
            students_array[i][j] = -1;
        }
    }
}

void free_array(int **students_array, size_t students_number) {
    for (size_t i = 0; i < students_number; i++) {
        free(students_array[i]);
    }
}

void print_student_array(int **students_array, size_t students_number, size_t grades_number) {
    printf("----------------------\n");
    for (size_t i = 0; i < students_number; i++) {
        printf("Student %zu : ", i);
        print_array(students_array[i], grades_number);
    }
    printf("----------------------\n");
}

int find_rank_student(int student_grade, int *grades_array, size_t students_number) {
    for (size_t i = 0; i < students_number; i++) {
        if (grades_array[i] == student_grade) {
            return i + 1;
        }
    }
    return -1;
}

void sort_students(int **students_rank, int **students_array, size_t students_number, size_t grades_number) {
    int *grades = malloc(students_number * sizeof(int));
    int *sorted_grades = malloc(students_number * sizeof(int));
    int *sums = calloc(students_number, sizeof(int));

    for (size_t i = 0; i < grades_number; i++) {
        for (size_t j = 0; j < students_number; j++) {
            sums[j] += students_array[j][i];
            grades[j] = sums[j] / (i + 1);
            sorted_grades[j] = grades[j];
        }

        heapsort(sorted_grades, students_number);
        for (size_t j = 0, k = students_number - 1; j < k; j++, k--) {
            int temp = sorted_grades[j];
            sorted_grades[j] = sorted_grades[k];
            sorted_grades[k] = temp;
        }

        for (size_t j = 0; j < students_number; j++) {
            students_rank[j][i] = find_rank_student(grades[j], sorted_grades, students_number);
        }
    }

    free(grades);
    free(sorted_grades);
    free(sums);
}

int main(int argc, char **argv) {
    if (argc != 4) {
        printf("Usage : %s <number of student> <number of grade per student> <debug mode : 0|1>\n", argv[0]);
        return -1;
    }

    size_t students_length = atoi(argv[1]);
    size_t grades_length = atoi(argv[2]);
    int debug_mode = atoi(argv[3]);

    int **student_grades = malloc(students_length * sizeof(int *));
    int **student_ranks = malloc(students_length * sizeof(int *));
    generate_grades(student_grades, students_length, grades_length);
    generate_ranks(student_ranks, students_length, grades_length);

    sort_students(student_ranks, student_grades, students_length, grades_length);

    if (debug_mode) {
        print_student_array(student_grades, students_length, grades_length);
        print_student_array(student_ranks, students_length, grades_length);
    }

    free_array(student_grades, students_length);
    free_array(student_ranks, students_length);
    free(student_grades);
    free(student_ranks);
    return 0;
}