#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#define MAX_BOOKS 100
#define MAX_TITLE_LENGTH 50
#define MAX_AUTHOR_LENGTH 50
// 枚举定义书籍类别
typedef enum BookCategory {
    FICTION,
    NONFICTION,
    SCIENCE,
    SPORTS,
    CATEGORY_COUNT // 用于统计类别数量
} BookCategory;
// 类型定义书籍结构体
typedef struct Book {
    char title[MAX_TITLE_LENGTH];
    char author[MAX_AUTHOR_LENGTH];
    BookCategory category;
} Book;
// 宏定义
#define MENU_OPTIONS 4
// 函数声明
void addBook(Book **books, int *count);
void deleteBook(Book **books, int *count);
void printBooks(Book **books, int count);
void exitProgram(Book **books, int *count);
// 函数指针数组，用于菜单操作
void (*menuFunctions[MENU_OPTIONS])(Book **, int *) = {
    addBook,
    deleteBook,
    printBooks,
    exitProgram
};
// 主函数
int main() {
    Book *books[MAX_BOOKS] = {0}; // 结构体指针数组
    int bookCount = 0;
    int choice;
    while (1) {
        printf("\nMenu:\n");
        printf("1. Add Book\n");
        printf("2. Delete Book\n");
        printf("3. Print Books\n");
        printf("4. Exit\n");
        printf("Enter choice: ");
        scanf("%d", &choice);
        if (choice < 1 || choice > MENU_OPTIONS) {
            printf("Invalid choice. Please try again.\n");
            continue;
        }
        // 调用相应的函数
        menuFunctions[choice - 1](&books[0], &bookCount);
        if (choice == MENU_OPTIONS) break; // 退出循环
    }
    return 0;
}
// 实现函数
void addBook(Book **books, int *count) {
    if (*count >= MAX_BOOKS) {
        printf("Maximum number of books reached.\n");
        return;
    }
    Book *newBook = (Book *)malloc(sizeof(Book));
    if (!newBook) {
        printf("Memory allocation failed.\n");
        return;
    }
    printf("Enter book title: ");
    scanf("%49s", newBook->title); // 防止溢出
    printf("Enter author name: ");
    scanf("%49s", newBook->author);
    printf("Enter category (0 for Fiction, 1 for Nonfiction, 2 for Science, 3 for Sports): ");
    scanf("%u", (unsigned int *)&newBook->category);
    books[*count] = newBook;
    (*count)++;
    printf("Book added successfully.\n");
}
void deleteBook(Book **books, int *count) {
    int index;
    printf("Enter index of book to delete: ");
    scanf("%d", &index);
    if (index < 0 || index >= *count) {
        printf("Invalid index.\n");
        return;
    }
    free(books[index]);
    for (int i = index; i < *count - 1; i++) {
        books[i] = books[i + 1];
    }
    books[*count - 1] = NULL;
    (*count)--;
    printf("Book deleted successfully.\n");
}
void printBooks(Book **books, int count) {
    if (count == 0) {
        printf("No books to display.\n");
        return;
    }
    printf("Books:\n");
    for (int i = 0; i < count; i++) {
        printf("%d: %s by %s, Category: %d\n", i, books[i]->title, books[i]->author, books[i]->category);
    }
}
void exitProgram(Book **books, int *count) {
    for (int i = 0; i < *count; i++) {
        free(books[i]);
    }
    printf("Exiting program...\n");
}