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

typedef struct Node
{
    char id[20];
    char phone[20];
    char dept[20];
    char bg[5];
    char adress[20];
    char name[20];
    struct Node *next;
} node;

void insert_after(node *p,char name[20], char id[20], char dept[20], char bg[5], char cont[20])
{
    while(p->next != NULL)
    {
        p = p->next;
    }
    p->next = (node *)malloc(sizeof(node));

    strcpy(p->next->name,name);
    strcpy(p->next->id,id);
    strcpy(p->next->dept,dept);
    strcpy(p->next->bg,bg);
    strcpy(p->next->phone,cont);
    p->next->next = NULL;
}
void insert_first(node *p,char name[20], char id[20], char dept[20], char bg[5], char cont[20])
{
    node *temp;
    temp = (node *)malloc(sizeof(node));

    strcpy(temp->name,name);
    strcpy(temp->id,id);
    strcpy(temp->dept,dept);
    strcpy(temp->bg,bg);
    strcpy(temp->phone,cont);

    temp->next = p->next;
    p->next = temp;
}
void edit_data(node *p,char id[])
{
    int n,ct=0;
    char name1[20];
    char id1[20];
    char dept1[20];
    char bg1[20];
    char phone1[20];
    //node *temp = search(p,id);
    p = p->next;
    while(p != NULL)
    {
        if(strcmp(p->id,id) == 0)
        {
            printf("\n---------------------------------------------------------------\n");
            printf("                 ****Student's Data To Edit****                 ");
            printf("\n---------------------------------------------------------------\n");

            printf("1.Student name       : %s\n", p->name);
            printf("2.Student ID         : %s\n", p->id);
            printf("3.Student Department : %s\n", p->dept);
            printf("4.Student Blood group: %s\n", p->bg);
            printf("5.Student Contact    : %s\n\n",p->phone);

            printf("Select your option to Edit: ");

            scanf("%d",&n);

            if(n == 1)
            {
                printf("Enter the name: ");
                scanf(" %[^\n]s",name1);
                strcpy(p->name,name1);
            }
            else if(n == 2)
            {
                printf("Enter the ID: ");
                scanf(" %s",id1);
                strcpy(p->id,id1);
            }
            else if(n == 3)
            {
                printf("Enter the Department: ");
                scanf("%s",dept1);
                strcpy(p->dept,dept1);
            }
            else if(n == 4)
            {
                printf("Enter the Blood Group: ");
                scanf("%s",bg1);
                strcpy(p->bg,bg1);
            }
            else if(n == 5)
            {
                printf("Enter the Contact: ");
                scanf("%s",phone1);
                strcpy(p->phone,phone1);
            }
            else
            {
                printf("\nError Selection!!\n");
            }
        }
        ct++;
        p = p -> next;
    }
    if(ct == 0)
        printf("\nElement not Found!\n");

}

int search(node *p, char id[20])
{
    p = p->next;
    while(p != NULL)
    {
        if(strcmp(p->id,id) == 0)
        {
            printf("\n---------------------------------------------------------------\n");
            printf("            ****Displaying Searched Information****              ");
            printf("\n---------------------------------------------------------------\n");

            printf("Student name       : %s\n", p->name);
            printf("Student ID         : %s\n", p->id);
            printf("Student Department : %s\n", p->dept);
            printf("Student Blood group: %s\n", p->bg);
            printf("Student Contact    : %s\n\n",p->phone);

            return;
        }
        p = p -> next;
    }
    printf("Sorry!Element not found.\n");
    return;
}
void blood_grp(node *p, char bg[5])
{
    int ct=0;
    p = p->next;
    printf("\n---------------------------------------------------------------\n");
    printf("            ****Information of Desired Blood Group****            ");
    printf("\n---------------------------------------------------------------\n");

    while(p != NULL)
    {
        if(strcmp(p->bg,bg)==0)
        {
            ct++;
            printf("\nStudent Name  : %s\n",p->name);
            printf("Blood Group   : %s\n",p->bg);
            printf("Contact number: %s\n",p->phone);
        }
        p = p->next;
    }
    if(ct == 0)
        printf("\nNot found\n");
}

void dept_search(node *p, char dept[20])
{
    int ct=0;
    p = p->next;
    printf("\n---------------------------------------------------------------\n");
    printf("            ****Department Wise Student Information****            ");
    printf("\n---------------------------------------------------------------\n");

    while(p != NULL)
    {
        if(strcmp(p->dept,dept)==0)
        {
            ct++;
            printf("Student name       : %s\n", p->name);
            printf("Student ID         : %s\n", p->id);
            printf("Student Department : %s\n", p->dept);
            printf("Student Blood group: %s\n", p->bg);
            printf("Student Contact    : %s\n\n", p->phone);
        }
        p = p->next;
    }
    if(ct == 0)
        printf("\nNot found\n");
}
void delete(node *p, char id[20])
{
    int ct=0;
    node *temp;
    while(p->next != NULL)
    {
        if(strcmp(p->next->id,id) == 0)
        {
            ct++;
            temp = p->next;
            p->next = temp->next;
            free(temp);
            return 0;
        }
        p = p->next;
    }
    if(ct == 0)
    {
        printf("Element Not Found!!\n");
    }
}

void display(node *p)
{
    while(p -> next != NULL)
    {
        printf("Student name       : %s\n", p->next->name);
        printf("Student ID         : %s\n", p->next->id);
        printf("Student Department : %s\n", p->next->dept);
        printf("Student Blood group: %s\n", p->next->bg);
        printf("Student Contact    : %s\n\n", p->next->phone);
        //printf("Student name: %s\n", p->next->name);
        p = p->next;
    }
}
void check_id(node *p,char id[])
{
    while(p->next != NULL)
    {
        if(strcmp(p->next->id,id)==0)
        {
            printf("\nThis ID Already exists!\n");
            printf("Enter a new ID please! :- ");
            scanf("%s",id);
        }
        p = p->next;
    }
}

int main()
{
    system("color f0");
    int s;
    char q;
    char name[20];
    char id[20];
    char dept[20];
    char bg[20];
    char phone[20];

    node *start = (node *)malloc(sizeof(node));
    start -> next = NULL;

    while(1)
    {

        printf("\n----------------------------------------------------------------------------\n");
        printf("                     Welcome to Student Database Management System"                    );
        printf("\n----------------------------------------------------------------------------\n");
        printf("\tLog in as:\n");
        printf(" \n\t\t 1. ADMIN \n\n\t\t 0. EXIT");
        printf("\n----------------------------------------------------------------------------\n");
        printf("                                                            "                    );
        printf("\n----------------------------------------------------------------------------\n");
        printf("\n\tEnter Choice:\t\t");
        int choice;
        scanf("%d",&choice);
        switch(choice)
        {
        case 1:
            while(1)
            {
                printf("\n\n1. Insert Student Data\n");
                printf("2. Delete Student Data\n");
                printf("3. Display\n");
                printf("4. Search\n");
                printf("5. Insert at first\n");
                printf("6. Edit Student information\n");
                printf("7. Search Blood Group\n");
                printf("8. Search Department\n");
                printf("9. Exit\n");

                printf("\nEnter your choice: ");

                scanf(" %c",&q);

                switch(q)
                {
                case '1':
                    system("CLS");
                    printf("\nIf your want to EXIT press '0' else press any key\n");
                    scanf("%d",&s);

                    if(s == 0)
                        break;
                    else
                    {
                        printf("\n---------------------------------------------------------------\n");
                        printf("                 Enter Student information                     ");
                        printf("\n---------------------------------------------------------------\n");
                        printf("Enter name: ");
                        scanf(" %[^\n]s", name);
                        printf("Enter ID: ");
                        scanf("%s", id);
                        check_id(start,id);
                        printf("Enter Department: ");
                        scanf(" %s", dept);
                        printf("Enter Blood Group: ");
                        scanf("%s", bg);
                        printf("Enter contact: ");
                        scanf("%s", phone);

                        insert_after(start,name,id,dept,bg,phone);
                    }
                    break;

                case '2':
                    system("CLS");
                    printf("\nIf your want to EXIT press '0' else press any key\n");
                    scanf("%d",&s);

                    if(s == 0)
                        break;
                    else
                    {
                        printf("Enter a Student's ID to Delete data: ");
                        scanf("%s", id);
                        delete(start,id);
                    }
                    break;

                case '3':
                    system("CLS");
                    printf("\nIf your want to EXIT press '0' else press any key\n");
                    scanf("%d",&s);

                    if(s == 0)
                        break;
                    else
                    {
                        printf("\n---------------------------------------------------------------\n");
                        printf("            ****Student's personal information****                ");
                        printf("\n---------------------------------------------------------------\n");
                        display(start);
                    }
                    break;
                case '4':
                    system("CLS");
                    printf("\nIf your want to EXIT press '0' else press any key\n");
                    scanf("%d",&s);

                    if(s == 0)
                        break;
                    else
                    {
                        printf("Enter the ID: ");
                        scanf("%s",id);
                        search(start,id);
                    }
                    break;
                case '5':
                    system("CLS");
                    printf("\nIf your want to EXIT press '0' else press any key\n");
                    scanf("%d",&s);

                    if(s == 0)
                        break;
                    else
                    {
                        printf("\n\nEnter student information\n\n");
                        printf("Enter name: ");
                        scanf(" %[^\n]s", name);
                        printf("Enter ID: ");
                        scanf("%s", id);
                        printf("Enter Department: ");
                        scanf(" %[^\n]s", dept);
                        printf("Enter Blood Group: ");
                        scanf("%s", bg);
                        printf("Enter contact: ");
                        scanf("%s", phone);

                        insert_first(start,name,id,dept,bg,phone);
                    }
                    break;
                case '6':
                    system("CLS");
                    printf("\nIf your want to EXIT press '0' else press any key\n");
                    scanf("%d",&s);

                    if(s == 0)
                        break;
                    else
                    {
                        printf("\nEnter the ID to Edit data: ");
                        scanf("%s",id);
                        edit_data(start,id);
                    }
                    break;
                case '7':
                    system("CLS");
                    printf("\nIf your want to EXIT press '0' else press any key\n");
                    scanf("%d",&s);

                    if(s == 0)
                        break;
                    else
                    {
                        printf("\nEnter the desired Blood Group: ");
                        scanf("%s",bg);
                        blood_grp(start,bg);
                    }
                    break;
                case '8':
                    system("CLS");
                    printf("\nIf your want to EXIT press '0' else press any key\n");
                    scanf("%d",&s);

                    if(s == 0)
                        break;
                    else
                    {
                        printf("\nEnter Department Name: ");
                        scanf("%s",dept);
                        dept_search(start,dept);
                    }
                    break;
                case '0':
                    exit(0);
                default:
                    system("CLS");
                    printf("Invalid choice.Try again!\n");
                    break;
                }
            }
            case 0:
                exit(0);
        }


    }
}