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

struct bookinfo
{
char title[50],author[50];
int isbn,price;
};



struct Node
{

struct bookinfo book;
 struct Node *next;
}*Head;

struct bookinfo getBook()
{
char name[50],auth[50];
int cost,sr;
struct bookinfo tempbook;
printf("Enter ISBN Number : ");
scanf("%d",&sr);
printf("Enter Book Name : ");
scanf("%s", name);
printf("Enter Book Author : ");
scanf("%s",auth);
printf("Enter Price : ");
scanf("%d",&cost);
tempbook.isbn = sr;
strcpy(tempbook.title,name);
strcpy(tempbook.author,auth);
tempbook.price = cost;

return(tempbook);
}

void addBook()
{
long int recsize;
struct bookinfo newbook = getBook();
struct Node *temp1, *temp2;

  temp1=(struct Node *)malloc(sizeof(struct Node));
  temp1->book = newbook;

  // Copying the Head location into another node.
  temp2=Head;

  if(Head == NULL)
  {
     // If List is empty we create First Node.
     Head=temp1;
     Head->next=NULL;
  }
  else
  {
     // Traverse down to end of the list.
     while(temp2->next != NULL)
     temp2=temp2->next;

     // Append at the end of the list.
     temp1->next=NULL;
     temp2->next=temp1;
  }
system("clear");
printf("\nBook Added Successfully\n");

FILE *fp,*fs;
fp = fopen("bookrecord.txt","a");
if (fp == NULL)
{
printf("Cannot open file");
}
fprintf ( fp, "\n %d \n %s \n %s \n %d\n", newbook.isbn, newbook.title, newbook.author, newbook.price ) ;
fflush (stdin) ;
fclose(fp);

fs = fopen( "BOOK.DAT", "rb+" ) ;
if ( fs == NULL )
{
fs = fopen ( "BOOK.DAT", "wb+" ) ;
if ( fs == NULL )
{
puts ( "Cannot open file" ) ;
}
}
recsize = sizeof (newbook) ;
fseek ( fs, 0 , SEEK_END ) ;
fwrite ( &newbook, recsize, 1, fs ) ;
fflush (stdin) ;
fclose(fs);
}


void listFile()
{

long int recsize;
struct bookinfo b1;
recsize = sizeof ( b1 ) ;

FILE *fp;
fp = fopen("BOOK.DAT","rb+");
if (fp == NULL)
{
printf("Cannot open file");
}

rewind (fp) ;
while ( fread ( &b1, recsize, 1, fp ) == 1 )
{printf ( "\n ISBN:%d \n Title:%s \n Author:%s \n Price:%d\n", b1.isbn, b1.title, b1.author, b1.price ) ;}
fclose(fp);
}



void display()
{
  struct Node *cur_ptr;

  cur_ptr=Head;

  if(cur_ptr==NULL)
  {
system("clear");
     printf("\nThere are No BOOKS in the List\n\n");
  }
  else
  {
	system("clear");
      printf("\nBooks : \n\n");
      //traverse the entire linked list
      while(cur_ptr!=NULL)
      {
          printf("ISBN : %d \n",cur_ptr->book.isbn);
          printf("Title : %s \n",cur_ptr->book.title);
          printf("Author : %s \n",cur_ptr->book.author);
          printf("Price : %d \n",cur_ptr->book.price);
          cur_ptr=cur_ptr->next;
	  printf("\n");
      }
      printf("\n");
  }

listFile();

}

int delBook(int num)
{

  int flag = 0,error = 440;
  struct Node *prev_ptr, *cur_ptr;

  cur_ptr=Head;

  while(cur_ptr != NULL)
  {
     if(cur_ptr->book.isbn == num)
     {
        if(cur_ptr==Head)
        {
           Head=cur_ptr->next;
           free(cur_ptr);
		system("clear");
           printf("\n Book Removed\n\n");
		flag = 1;
		return(1);
	break;
        }
        else
        {
           prev_ptr->next=cur_ptr->next;
           free(cur_ptr);
		system("clear");
           printf("\n Book Removed\n\n");
		flag = 1;
		return(1);
	break;
        }

     }
     else
     {
        prev_ptr=cur_ptr;
        cur_ptr=cur_ptr->next;

     }
if(flag == 0){
flag = flag + error;
	system("clear");
	printf("\nBook(ISBN %d) not found in the List\n\n", num);
}
  }
return(flag);

}


int search(int num)
{

  int flag = 0,error=404;
  struct Node *prev_ptr, *cur_ptr;

  cur_ptr=Head;

  while(cur_ptr != NULL)
  {
     if(cur_ptr->book.isbn == num)
     {
		system("clear");
          printf("\nBook Found \n\n");
    	  printf("ISBN : %d \n",cur_ptr->book.isbn);
          printf("Title : %s \n",cur_ptr->book.title);
          printf("Author : %s \n",cur_ptr->book.author);
          printf("Price : %d \n",cur_ptr->book.price);
          cur_ptr=cur_ptr->next;
	  printf("\n");
	  flag = 1;
		return(1);
	  break;
     }
     else
     {
        prev_ptr=cur_ptr;
        cur_ptr=cur_ptr->next;

     }
if(flag == 0){
flag = flag + error;
		system("clear");
	printf("\nBook(ISBN %d) not found in the List\n\n", num);
}
  }
   return(flag);
}



void menu()
{
printf("\nMenu : ");
printf("\n**********************************************************************");
printf("\nEnter 1 to Add New Book");
printf("\nEnter 2 to Remove Existing Book");
printf("\nEnter 3 to List All Books");
printf("\nEnter 4 to Search a Book");
printf("\nEnter 0 to Quit");
printf("\n************************************************************************");
}

void main()
{
system("clear");
int success;
int found;
int delISBN;
int searchISBN;
int choice;

do
{
menu();
printf("\nEnter your choice : ");
scanf("%d",&choice);
switch(choice)
{
case 1:
addBook();break;
case 2:
printf("Enter ISBN to Delete Book : ");
scanf("%d",&delISBN);
success = delBook(delISBN);
if(success != 440 && success != 1){printf("\nBook Not Available\n");success = 9;}
break;
case 3:
display();
break;
case 4:
printf("Enter ISBN to Search Book : ");
scanf("%d",&searchISBN);
found = search(searchISBN);
if(found != 404 && found != 1){printf("\nBook Not Available\n");found = 10;}
break;
case 0:
printf("\nThank You for using our Service\n\n");
break;
default:
printf("Please Enter a Valid Choice !");
}
}while(choice!=0);

}