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

#pragma warning(disable: 4996)

struct Item{                       // a node to hold personal details
    char name[255];
    float price;  // Price for each item.
    int quantity;
    struct Item *next;
}*head=NULL;

void flush();                         // forward declaration of functions
void branching(char c);
int insert();
void print();
struct search();
void delete();

int main() {  // print a menu for selection
    char ch = 'i';

    ungetc('\n', stdin); // inject input buffer with a return character

    do {
        printf("Enter your selection\n");
        printf("\ti: insert a new item\n");
        printf("\td: delete an item\n");
        printf("\tp: print all items\n");
        printf("\tq: quit \n");

        flush();                    // flush input buffer
        ch = tolower(getchar());
        branching(ch);
    } while (ch != 113);

    return 0;
}

void flush() {
    int c;
    do {
        c = getchar();
    } while (c != '\n' && c != EOF);
}

void branching(char c) {    // branch to different tasks
    switch (c) {
    case 'i':
        insert();
        break;
    case 'd':
        delete();
        break;
    case 'p':
        print();
        break;
    case 'q':
        break;
    default:
        printf("Invalid input\n");
    }
}

int insert() {    // insert a new entry
    struct Item *p;
    p = malloc(sizeof(struct Item));
    if (p == 0) {
        printf("out of memory\n");  return -1;
    }
    printf("Enter name, price, quantity: \n");
    scanf("%s", p->name);   // p->name is array
    scanf("%f", &p->price);
    scanf("%d", &p->quantity);
    p->next = head;
    head = p;
    return 0;
}

struct Item* search() {    // search for position to delete
    char sname[32];
    struct Item *p = head, *b = p;
    printf("please enter the name to be searched for:\n");
    scanf("%s", sname);
    while (p != 0)
        if (stricmp(sname, p->name)== 0) {
            return p;
        }
        else {b = p; p = p->next;}
    printf("The name does not exist.\n");
    return 0;
}

void delete() {
    struct Item *b;
    if (head == 0)  return;     // nothing to delete
    b = search();       // find the position
    if (b == 0) {   // free head        // case 1
        free(head); // C garbage collection
        head = head->next;
        return;
    }
    if (b->next->next == 0) {   // case 2
        free(b->next);
        b->next = 0;
        return;
    } else {
        free(b->next);
        b->next = b->next->next;    // case 3
        return;
    }
}

void print(){
    float total = 0;
    // .. element to L

    // Iterate each node and print
     struct Item* n = &ShoppingList;

    do{
        printf("Item: %s\n", n->name);
        printf("Quantity: %d\n", &n->quantity);
        printf("Price: %f\n", &n->price);
        total += (&n->quantity)*(&n->price);
        n = n->next;
    }
        while(n != NULL)
    printf("Grand Total: %f\n", total);
}