#include "pch.h"
#include <stdio.h>
#include <stdlib.h>
struct student {
	student *nextStudent;
	student *prevStudent;
	int studentAge;
	char *studentName;
	int studentGrade;
};
char* setStudentName(char* name) {
	int i = 0;
	if (!(name = (char*)malloc(sizeof(char)))) {
		printf("Memory allocation problem\n");
		exit(1);
	}
	while (1) {
		name[i++] = (char)getchar();
		if (name[i - 1] == '\n') {
			name[i - 1] = '\0';
			break;
		}
		if (!(name = (char*)realloc(name, i + 2))) {
			printf("Memory allocation problem\n");
			exit(1);
		}
	}
	i = 0;
	if (name[0] == '\0') {
		printf("Incorrect name,reenter!\n");
		rewind(stdin);
		setStudentName(name);
	}
	while (name[i] != '\0') {
		if (!(name[i] >= 'a' && name[i] <= 'z' || name[i] >= 'A' && name[i] <= 'Z')) {
			printf("Incorrect information in name,reenter!\n");
			free(name);
			rewind(stdin);
			setStudentName(name);
		}
		i++;
	}
	return name;
}
student* addElementInHead(student** head) {
	student *currentElement;
	if (!(currentElement = (student*)malloc(sizeof(student)))) {
		printf("Memory allocation problem\n");
		exit(1);
	}
	printf("Enter student name\n");
	rewind(stdin);
	currentElement->studentName = setStudentName(currentElement->studentName);
	printf("Enter student age\n");
	while ((scanf_s("%d", &currentElement->studentAge)) != 1 || currentElement->studentAge <= 0) {
		printf("Incorrect information,reenter!\n");
		rewind(stdin);
	}
	printf("What the grade of student?\n");
	while ((scanf_s("%d", &currentElement->studentGrade)) != 1 || currentElement->studentGrade <= 0 || currentElement->studentGrade >= 7) {
		printf("Incorrect information,reenter!\n");
		rewind(stdin);
	}
	currentElement->nextStudent = *head;
	(*head)->prevStudent = currentElement;
	currentElement->prevStudent = NULL;
	*head = currentElement;
	return *head;
}
student* addElementInTail(student** tail) {
	student *currentElement;
	if (!(currentElement = (student*)malloc(sizeof(student)))) {
		printf("Memory allocation problem\n");
		exit(1);
	}
	printf("Enter student name\n");
	rewind(stdin);
	currentElement->studentName = setStudentName(currentElement->studentName);
	printf("Enter student age\n");
	while ((scanf_s("%d", &currentElement->studentAge)) != 1 || currentElement->studentAge <= 0) {
		printf("Incorrect information,reenter!\n");
		rewind(stdin);
	}
	printf("What the grade of student?\n");
	while ((scanf_s("%d", &currentElement->studentGrade)) != 1 || currentElement->studentGrade <= 0 || currentElement->studentGrade >= 7) {
		printf("Incorrect information,reenter!\n");
		rewind(stdin);
	}
	currentElement->prevStudent = *tail;
	(*tail)->nextStudent = currentElement;
	currentElement->nextStudent = NULL;
	*tail = currentElement;
	return *tail;
}
student* setList(student** head, student** tail) {
	student *currentElement;
	if (!(currentElement = (student*)malloc(sizeof(student)))) {
		printf("Memory allocation problem\n");
		exit(1);
	}
	printf("Enter student name\n");
	rewind(stdin);
	currentElement->studentName = setStudentName(currentElement->studentName);
	printf("Enter student age\n");
	while ((scanf_s("%d", &currentElement->studentAge)) != 1 || currentElement->studentAge <= 0) {
		printf("Incorrect information,reenter!\n");
		rewind(stdin);
	}
	printf("What the grade of student?\n");
	while ((scanf_s("%d", &currentElement->studentGrade)) != 1 || currentElement->studentGrade <= 0 || currentElement->studentGrade >= 7) {
		printf("Incorrect information,reenter!\n");
		rewind(stdin);
	}
	*head = *tail = currentElement;
	(*head)->nextStudent = (*tail)->prevStudent = NULL;
	return *head;
}
void showStudent(student* head) {
	student *tmpElement = head;
	while (tmpElement) {
		printf("Student name : %s\n", tmpElement->studentName);
		printf("Student age : %d\n", tmpElement->studentAge);
		printf("Student grade : %d\n", tmpElement->studentGrade);
		tmpElement = tmpElement->nextStudent;
	}
}
student* deleteAllElements(student** head,student** tail) {
	while (*head != NULL) {
		*head = (*head)->nextStudent;
	}
	return *head;
}
int NumberOfElements(student* head) {
	student *tmpElement;
	int studentCounter = 0;
	tmpElement = head;
	while (tmpElement != NULL) {
		studentCounter++;
		tmpElement = tmpElement->nextStudent;
	}
	return studentCounter;
}
bool isEmpty(student* head) {
	student *tmpElement;
	int elementCounter = 0;
	tmpElement = head;
	while (tmpElement != NULL) {
		elementCounter++;
		tmpElement = tmpElement->nextStudent;
	}
	if (elementCounter == 0)
		return true;
	else return false;
}
student* deleteHead(student** head) {
	*head = (*head)->nextStudent;
	if (*head != NULL) {
		(*head)->prevStudent = NULL;
	}
	return *head;
}
student* deleteTail(student** tail) {
	*tail = (*tail)->prevStudent;
	if (*tail != NULL) {
		(*tail)->nextStudent = NULL;
	}
	return *tail;
}
int searchElement(student* head) {
	student *tmpElement = head;
	int age;
	while ((scanf_s("%d", &age)) != 1 || age <= 0) {
		printf("Incorrect information,reenter!\n");
		rewind(stdin);
	}
	while (tmpElement != NULL) {
		if (tmpElement->studentAge == age) {
			break;
		}
		else {
			tmpElement = tmpElement->nextStudent;
		}
	}
	if (tmpElement == NULL) {
		printf("No element's like this,reenter!\n");
		rewind(stdin);
		searchElement(head);
	}
	return age;
}
student* deleteElement(int newElement, student** head, student** tail) {
	student *tmpElement = *head, *currentElement = *head;
	while (currentElement->studentAge != newElement) {
		currentElement = currentElement->nextStudent;
	}
	if (currentElement == *head || currentElement == *tail) {
		if (currentElement == *head) {
			*head = (*head)->nextStudent;
			if (*head != NULL) {
				(*head)->prevStudent = NULL;
			}
		}
		else {
			*tail = (*tail)->prevStudent;
			if (*tail != NULL) {
				(*tail)->nextStudent = NULL;
			}
		}
	}
	else {
		while (tmpElement->nextStudent != currentElement) {
			tmpElement = tmpElement->nextStudent;
		}
		tmpElement->nextStudent = currentElement->nextStudent;
		if (currentElement->nextStudent != NULL) {
			currentElement->nextStudent->prevStudent = tmpElement;
		}
	}
	return *head;
}
void showMinAndMaxElements(student* head) {
	student *tmpElement = head;
	int min, max;
	min = tmpElement->studentAge;
	max = tmpElement->studentAge;
	while (tmpElement->nextStudent != NULL) {
		if (tmpElement->studentAge < min) {
			min = tmpElement->studentAge;
		}
		tmpElement = tmpElement->nextStudent;
	}
	tmpElement = head;
	while (tmpElement != NULL) {
		if (tmpElement->studentAge > max) {
			max = tmpElement->studentAge;
		}
		tmpElement = tmpElement->nextStudent;
	}
	printf("Minimal element in list - %d\nMaximal element in list - %d\n", min, max);
}
student* deleteAllElementsWithThisValue(int newElement, student** head, student** tail) {
	student *tmpElement = *head, *currentElement = *head;
	while (currentElement != NULL && head != NULL) {
		tmpElement = *head;
		if (currentElement->studentAge == newElement) {
			if (currentElement == *head || currentElement == *tail) {
				if (currentElement == *head) {
					*head = (*head)->nextStudent;
					if (*head != NULL) {
						(*head)->prevStudent = NULL;
					}
				}
				else {
					*tail = (*tail)->prevStudent;
					if (*tail != NULL) {
						(*tail)->nextStudent = NULL;
					}
				}
			}
			else {
				while (tmpElement->nextStudent != currentElement) {
					tmpElement = tmpElement->nextStudent;
				}
				tmpElement->nextStudent = currentElement->nextStudent;
				if (currentElement->nextStudent != NULL) {
					currentElement->nextStudent->prevStudent = tmpElement;
				}
			}
		}
		currentElement = currentElement->nextStudent;
	}
	return *head;
}
student* replaceValueOfElements(int newElement, int newValue, student* head) {
	student *currentElement = head;
	while (currentElement != NULL) {
		if (currentElement->studentAge == newElement) {
			currentElement->studentAge = newValue;
		}
		currentElement = currentElement->nextStudent;
	}
	return head;
}
student* removeDuplicateElements(student** head, student** tail) {
	bool flag = true;
	student *tmpElement = *head, *currentElement = *head, *tmpElement2 = *head;
	if (*head != *tail) {
		while (currentElement->nextStudent != NULL) {
			tmpElement = currentElement->nextStudent;
			while (tmpElement != NULL) {
				if (tmpElement->studentAge == currentElement->studentAge) {
					if (tmpElement == *head || tmpElement == *tail) {
						if (tmpElement == *head) {
							*head = (*head)->nextStudent;
							if (*head != NULL) {
								(*head)->prevStudent = NULL;
							}
						}
						else
						{
							*tail = (*tail)->prevStudent;
							if (*tail != NULL) {
								(*tail)->nextStudent = NULL;
							}
						}
						flag = false;
					}
					else {
						tmpElement2 = *head;
						flag = false;
						while (tmpElement2->nextStudent != tmpElement)
							tmpElement2 = tmpElement2->nextStudent;
						tmpElement2->nextStudent = tmpElement->nextStudent;
						if (tmpElement->nextStudent != NULL) {
							tmpElement->nextStudent->prevStudent = tmpElement2;
						}
					}
				}
				tmpElement = tmpElement->nextStudent;
			}
			if (flag == false) {
				if (currentElement == *head || currentElement == *tail) {
					if (currentElement == *head) {
						*head = (*head)->nextStudent;
						if (*head != NULL) {
							(*head)->prevStudent = NULL;
						}
					}
					else {
						*tail = (*tail)->prevStudent;
						if (*tail != NULL) {
							(*tail)->nextStudent = NULL;
						}
					}
				}
				else {
					tmpElement2 = *head;
					while (tmpElement2->nextStudent != currentElement)
						tmpElement2 = tmpElement2->nextStudent;
					tmpElement2->nextStudent = currentElement->nextStudent;
					if (currentElement->nextStudent != NULL) {
						currentElement->nextStudent->prevStudent = tmpElement2;
					}
				}
			}
			if (currentElement != NULL) {
				currentElement = currentElement->nextStudent;
			}
			if (currentElement == NULL || *head == *tail) {
				break;
			}
			flag = true;
		}
	}
	return *head;
}
int main() {
	student *head = NULL, *tail = NULL;
	int typeOfOption = 0, element, newValue, newElement, numberOfStudents;
	bool isElement = false;
	printf("Choose option : \n1)Set list of students\n2)Add element in head\n3)Add element in tail\n4)Show elements\n5)Delete all elements\n6)Number of element's in list\n7)Is empty?\n8)Delete 1st element\n9)Delete last element\n10)Search 1 element\n11)Delete element\n12)Search minimal and maximal element\n13)Delete all elements with this value\n14)Replace value of all choosen elements\n15)Remove duplicate elements\n16)Exit\n");
	while (typeOfOption != 16) {
		printf("Enter option number\n");
		while ((scanf_s("%d", &typeOfOption)) != 1 || typeOfOption <= 0 || typeOfOption >= 17) {
			rewind(stdin);
			printf("Incorrect,reenter!\n");
		}
		switch (typeOfOption) {
		case 1: {
			if (isEmpty(head) == true) {
				head = setList(&head, &tail);
			}
			else {
				printf("Your already have list\n");
			}
			break;
		}
		case 2: {
			if (isEmpty(head) == true) {
				printf("List not created\n");
			}
			else {
				head = addElementInHead(&head);
			}
			break;
			if (isEmpty(head) == true) {
				printf("List not created\n");
			}
			else {
				tail = addElementInTail(&tail);
			}
			break;
		}
		case 3: {
			if (isEmpty(head) == true) {
				printf("List not created\n");
			}
			else {
				tail = addElementInTail(&tail);
			}
			break;
		}
		case 4: {
			if (isEmpty(head) == true) {
				printf("List not created\n");
			}
			else {
				showStudent(head);
			}
			break;
		}
		case 5: {
			if (isEmpty(head) == true) {
				printf("List not created\n");
			}
			else {
				head = deleteAllElements(&head, &tail);
			}
			break;
		}
		case 6: {
			printf("Elements in your list - %d\n", numberOfStudents = NumberOfElements(head));
			break;
		}
		case 7: {
			if ((isEmpty(head)) == true) {
				printf("Your list is empty\n");
			}
			else {
				printf("Your list is not empty\n");
			}
			break;
		}
		case 8: {
			if (isEmpty(head) == true) {
				printf("List not created\n");
			}
			else {
				head = deleteHead(&head);
			}
			break;
		}
		case 9: {
			if (isEmpty(head) == true) {
				printf("List not created\n");
			}
			else {
				tail = deleteTail(&tail);
			}
			break;
		}
		case 10: {
			if (isEmpty(head) == true) {
				printf("List not created\n");
			}
			else {
				printf("Enter value of element you want to search\n");
				newElement = searchElement(head);
				isElement = true;
			}
			break;
		}
		case 11: {
			if (isEmpty(head) == true) {
				printf("List not created\n");
			}
			else if (isElement == true) {
				head = deleteElement(newElement, &head, &tail);
				printf("Element deleted\n");
			}
			else {
				printf("No element's to search,type 10 on keyboard to choose what to find\n");
			}
			isElement = false;
			break;
		}
		case 12: {
			if (isEmpty(head) == true) {
				printf("List not created\n");
			}
			else {
				showMinAndMaxElements(head);
			}
			break;
		}
		case 13: {
			if (isEmpty(head) == true) {
				printf("List not created\n");
			}
			else if(isElement == true){
				head = deleteAllElementsWithThisValue(newElement, &head, &tail);
			}
			else {
				printf("No element's to search,type 10 on keyboard to choose what to find\n");
			}
			isElement = false;
			break;
		}
		case 14: {
			if (isEmpty(head) == true) {
				printf("List not created\n");
			}
			else if(isElement == true){
				printf("Enter new value for elements\n");
				while ((scanf_s("%d", &newValue)) != 1) {
					printf("Incorrect information,reenter!\n");
					rewind(stdin);
				}
				head = replaceValueOfElements(newElement, newValue, head);
			}
			else {
				printf("No element's to search,type 10 on keyboard to choose what to find\n");
			}
			isElement = false;
			break;
		}
		case 15: {
			if (isEmpty(head) == true) {
				printf("List not created\n");
			}
			else {
				head = removeDuplicateElements(&head, &tail);
			}
			break;
		}
		}
	}
	return 0;
}