#define _CRT_SECURE_NO_WARNINGS
#include<stdio.h>
#include<string.h>
#include<stdlib.h>
#include<assert.h>
#include<windows.h>

//描述一个联系人的情况
typedef struct PersonInfo {
	char name[1024];
	char phone[1024];
}PersonInfo;

//描述一个通讯录.
typedef struct AddressBook {
	//最多保存1024个联系人
	PersonInfo persons[1024];
	//size表示当前保存了多少个联系人.
	int size;
}AddressBook;

//设置全局变量,实现通讯录,addressBook贯穿程序始终
AddressBook addressBook;

void init(AddressBook* addressBook) {
	//把通讯录的有效元素个数设为0.
	addressBook->size = 0;
	memset(addressBook->persons, 0, sizeof(addressBook->persons));
}

int menu() {
	printf("+------------------------------------------+\n");
	printf("|              欢迎使用通讯录!             |\n");
	printf("+------------------------------------------+\n");
	printf("|              1.新增联系人!               |\n");
	printf("|              2.删除联系人!               |\n");
	printf("|              3.查看联系人!               |\n");
	printf("|              4.修改联系人!               |\n");
	printf("|              0.退出                      |\n");
	printf("+------------------------------------------+\n");
	printf("请输入你的选项:");
	int choice = 0;
	scanf("%d", &choice);
	return choice;
}

void insert(AddressBook* addressBook) {
	printf("新增联系人!\n");
	//最大保存1024个联系人,如果超过1024则新增失败
	assert(addressBook != NULL);
	if (addressBook->size >= 1024) {
		printf("新增联系人失败!");
		return;
	}
	PersonInfo person = { 0 };
	printf("请输入新联系人的姓名:");
	scanf("%s", person.name);
	printf("请输入新联系人的电话:");
	scanf("%s", person.phone);
	//把person结构体放到AddressBook中
	addressBook->persons[addressBook->size] = person;
	addressBook->size++;
	printf("新增联系人成功!");
}

void drop(AddressBook* addressBook) {
	printf("删除联系人!\n");
	//用户输入一个序号根据序号删除.
	printf("请输入要删除联系人的序号:");
	int id = 0;
	scanf("%d", &id);
	//判断输入是否正确
	if (id < 0 || id >= addressBook->size) {
		printf("输入序号有误,删除失败");
		return;
	}
	if (id == addressBook->size - 1) {
		addressBook->size--;
		printf("删除成功!\n");
		return;
	}
	PersonInfo* lastPerson = &addressBook->persons[addressBook->size - 1];
	addressBook->persons[id] = *lastPerson;
	addressBook->size--;
	printf("删除成功!\n");
	return;
}

void show(AddressBook* addressBook) {
	printf("查看联系人!\n");
	//遍历联系人
	for (int i = 0; i < addressBook->size; i++) {
		PersonInfo* p = &addressBook->persons[i];
		printf("[%d] %s\t%s\n", i, p->name, p->phone);
	}
	printf("查看完毕!共有%d个联系人", addressBook->size);
}

void update(AddressBook* addressBook) {
	printf("修改联系人!\n");
	printf("请输入要修改的联系人序号:");
	int id = 0;
	scanf("%d", id);
	if (id < 0 || id >= addressBook->size) {
		printf("您输入的序号有误,修改失败!");
		return;
	}
	PersonInfo* p = &addressBook->persons[id];
	char name[1024] = { 0 };
	char phone[1024] = { 0 };
	printf("输入 * 表示该项不修改!");
	printf("请输入您新的用户名(旧的名字为%s):",p->name);
	scanf("%s", name);
	if (strcmp(name,"*") != 0) {
		strcpy(p->name,name);
	}
	printf("请输入新的电话号码(旧的电话为%s):",p->phone);
	scanf("%s", phone);
	if (strcmp(phone, "*") != 0) {
		strcpy(p->phone,phone);
	}
}

typedef void(*Func)(AddressBook*);
int main() {
	//进行初始化
	init(&addressBook);
	Func funcs[] = {
		NULL,//占位置,让insert和choice对上
		insert,
		drop,
		show,
		update
	};
	//和用户交互
	while (1) {
		int choice = menu();
		if (choice < 0 || choice >= sizeof(funcs)/sizeof(funcs[0])) {
			printf("您的输入有误!");
			continue;
		}
		if (choice == 0) {
			printf("goodbey!");
			break;
		}
		funcs[choice](&addressBook);
		system("pause");
		system("cls");
	}

	return 0;
}