#include <stdio.h>
#include <stdlib.h>
#include <malloc.h>
#include <iostream>
#include <windows.h>
#define L 81

struct Student{
	struct{
		char name[L];
		char surname[L];
		char patronymic[L];
	} fullName;
	char group[L];
	struct{
		int b[5];
		double average;
	} marks;
	Student *prev;
	Student *next;
};

float calculateAverage(int marks[]){
	int sum = 0;
	for (int i = 0; i < 5; i++){
		sum += marks[i];
	}
	return float(sum) / 5;
}

bool checkIsNotDigit(char s[]){
	char *p;
	for (p = s; *p && !(*p >= '0' &&*p <= '9'); p++);
	if (*p)
		return false;
	return true;
}
//здесь надо дописать isdigit и запустить проект в КуТи, иначе можно словить вылет и сдохнуть
bool checkMark(int m){
	return (m >= 0 && m <= 10);
}

void inputInfo(Student *uk, FILE *f){
	int a = 0;
	bool check;
	if (!fscanf(f, "%s", uk->fullName.surname) || !checkIsNotDigit(uk->fullName.surname)
		|| !fscanf(f, "%s", uk->fullName.name) || !checkIsNotDigit(uk->fullName.name)
		|| !fscanf(f, "%s", uk->fullName.patronymic) || !checkIsNotDigit(uk->fullName.patronymic)
		) {
		printf("Error in input.\n");
		exit(1);
	}
	if (!fscanf(f, "%s", uk->group)){
		printf("Error in input.\n");
		exit(1);
	}
	for (int i = 0; i < 5; i++)
		if (!fscanf(f, "%d", &uk->marks.b[i]) || !checkMark(uk->marks.b[i])){
			printf("Error in input.\n");
			exit(1);
		};
	uk->marks.average = calculateAverage(uk->marks.b);
}

Student *input(char filename[])
{
	FILE *f; char *n;
	Student *uk, *first = NULL, *add, *last = NULL;
	bool check;
	if (!(f = fopen(filename, "r")))
	{
		printf("No such file.\n");
		exit(1);
	}
	while (!(feof(f)))
	{
		if (!first){
			first = new Student;
			inputInfo(first, f);
			last = first;
		}
		add = new Student; //память для добавляемой записи
		inputInfo(add, f);
		last->next = add; //присоединим эту запись к списку
		add->prev = last; // сделаем в обратную сторону
		last = add; //сделаем эту запись последней
	}
	last->next = first; //зацикливаем
	first->prev = last;
	return(first); //вернем адрес начала списка
}

void output(Student *catalog){
	int j = 0;
	Student *head = catalog;
	if (!catalog) puts("The list is empty\n");
	else
		do
		{
			printf("\nStudent %d:\n", j);
			printf("%s\n", catalog->fullName.surname);
			printf("%s\n", catalog->fullName.name);
			printf("%s\n", catalog->fullName.patronymic);
			printf("%s\n", catalog->group);
			for (int i = 0; i < 5; i++)
				printf("%3d", catalog->marks.b[i]);
			printf("\n Average mark: %.2f", catalog->marks.average);
			printf("\n\n");
			j++;
			catalog = catalog->next;
		} while (catalog != head);
}

Student *filtrate(Student *catalog, char name[L], bool *flag){
	Student *old,*uk, *stack = NULL;
	old = catalog;
	do
	{
		if (strcmp(old->fullName.name, name) != 0){
			uk = new Student;
			uk->next = stack;
			stack = uk;
			strcpy(uk->fullName.name, old->fullName.name);
			strcpy(uk->fullName.surname, old->fullName.surname);
			strcpy(uk->fullName.patronymic, old->fullName.patronymic);
			strcpy(uk->group, old->group);
			for (int i = 0; i < 5; i++)
				uk->marks.b[i] = old->marks.b[i];
			uk->marks.average = old->marks.average;
			uk->prev = NULL;
			*flag = true;
		}
		old = old->next;
	} while (old && old != catalog);
	return (stack);
}

Student *filtrateByMarks(Student *catalog, bool *flag){
	Student *old, *uk, *stack = NULL;
	old = catalog;


	return (catalog);
}


void to_file(Student *catalog, char *filename2)
{
	FILE *f;
	int i;
	f = fopen(filename2, "w");
	while (catalog)
	{
		fprintf(f, "%s\n", catalog->fullName.name);
		fprintf(f, "%s\n", catalog->fullName.surname);
		fprintf(f, "%s\n", catalog->fullName.patronymic);
		fprintf(f, "%s\n", catalog->group);
		for (i = 0; i < 5; i++)
			fprintf(f, "%3d", catalog->marks.b[i]);
		fprintf(f, "\nAverage mark: %.3f\n\n", catalog->marks.average);
		catalog = catalog->next;
	}
	fclose(f);
}

void freemem(Student *catalog)
{
	Student *next = catalog;
	do
	{
		next = catalog->next;
		delete (catalog);     // Освобождение памяти
		catalog = next;
	} while (next && next != catalog);
}

int main()
{
	SetConsoleOutputCP(1251);
	SetConsoleCP(1251);

	char filename[L], filename2[L], name[L];
	bool flag = false;
	Student *catalog, *head;
	printf("Enter filename: \n");
	gets(filename);
	printf("\n");
	catalog = input(filename);
	output(catalog);
	printf("Enter name: \n");
	gets(name);
	head = filtrate(catalog, name, &flag);
	if (!head) puts("\nNone of the students have other name\n");
	else if (!flag) puts("\nNo filtration is needed\n");
	else
	{
		printf("Enter filename of other file\n");
		gets(filename2);
		to_file(head, filename2);
		printf("\nSuccessful sorting\n");
	}
	freemem(catalog);
	if (head)freemem(head);
	return 0;
}