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

#define MAXTEL 11
#define MAXNAME 10
#define MAXEMAIL 20

/*记录结构*/
struct record
{
    char name[MAXNAME+1];
    char sex;                   //'M' 或'F'
    char tel[MAXTEL+1];
    char email[MAXEMAIL+1];     //以email作为记录主键
};


/*链表节点结构*/
struct lnode
{
    struct record data;
    struct lnode *next;
};


/*函数声明*/
void Add(struct lnode *list);
void Search(struct lnode *list);
void Delete(struct lnode *list);
void Display(struct lnode *list);
struct lnode *SearchPrimarykey(struct lnode *list, char *key);
void InsertList(struct lnode *list, struct lnode *n);
void FreeList(struct lnode *list);
void DisplayTableHead(void);
void DisplayRecord(struct lnode *r);
void DisplayMenu(void);


/*主程序*/
int main(int argc, char *argv[])
{
    struct lnode *addressBook;
    /*功能选择，依次为：退出、添加、查找、删除、显示所有记录*/
    enum {EXIT, ADD, SEARCH, DEL, DISP} function = DISP;


    /*头结点*/
    addressBook = (struct lnode *)malloc(sizeof(struct lnode));
        if (addressBook != NULL)
    {
        addressBook->next = NULL;               //头结点next指针初始化为NULL*/
    }

    while (function != EXIT)
    {
        DisplayMenu();
        scanf("%d", &function);
        while (function < EXIT || function > DISP)
        {
            scanf("%d",&function);
        }

        switch(function)
        {
        case ADD:
            Add(addressBook);
            break;

        case SEARCH:
            Search(addressBook);
            break;
            
        case DEL:
            Delete(addressBook);
            break;

        case DISP:
            Display(addressBook);
            break;

        case EXIT:
            function = 0;
            break;

        default:
            printf("Input Error! Please input the right number.");
            break;
        }
    }

    FreeList(addressBook);
}


/*添加*/
void Add(struct londe *list)
{
    int i;
    struct record t;
    struct lnode *n, *r;


    /*录入记录*/
    printf("Please input the name: ");
    scanf("%s", t.name);
    fflush(stdin);
    printf("Please input the sex (M or F): ");
    scanf("%c", &t.sex);
    printf("Please input the tel: ");
    scanf("%s", t.tel);
    printf("Please input the email: ");
    scanf("%s", t.email);

    /*判断记录是否已经存在，若存在则显示记录，否则添加记录*/
    if ((r = SearchPrimarykey(list, t.email)) == NULL)
    {
        /*申请lnode空间并初始化*/
        n = (struct lnode *)malloc(sizeof(struct lnode));
        if (n != NULL)
        {
            /*复制记录*/
            strcpy((n->data).name, t.name);
            (n->data).sex = t.sex;
            strcpy((n->data).tel, t.tel);
            strcpy((n->data).email, t.email);
            /*插入链表*/
            InsertList(list, n);
        }
    }
    else
    {
        printf("Record Existed!\n");
        DisplayTableHead();
        DisplayRecord(r);
    }
}

/*查找*/
void Search(struct lnode *list)
{
    char e[MAXEMAIL];
    struct lnode *r;

    printf("Please input the Email you want to search: ");
    scanf("%s", e);

    if ((r = SearchPrimarykey(list, e)) != NULL)
    {
        DisplayTableHead();
        DisplayRecord(r);
    }
}


/*删除*/
void Delete(struct lnode *list)
{
    char e[MAXEMAIL];
    struct lnode *q, *p;
    q = list;
    p = list->next;

    printf("Please input the Email you want to Delete: ");
    scanf("%s", e);

    while (p != NULL)
    {
        if (strcmp((p->data).email, e) == 0)
        {
            q->next = p->next;
            free(p);          //释放空间
            return;           //函数返回
        }
        q = q;
        p = p->next;
    }
}


/*显示所有记录*/
void Display(struct lnode *list)
{
    int c = 0;
    struct lnode *p = list->next;


    printf("\n----------------- AddressBook Display -------------\n");
    DisplayTableHead();
    while (p != NULL)
    {
        DisplayRecord(p);
        c++;                    //记录条数
        p = p->next;
    }
    printf("\n----------------- Total: %d Reacord(s) -------------\n", c);
}

/*按主键查找*/
struct lnode *SearchPrimarykey(struct lnode *list, char *key)
{
    struct lnode *p = list->next;

    while (p !=NULL)
    {
        if (strcmp((p->data).email, key) == 0)
        {
            return p;               //返回函数
        }
        p = p->next;
    }
    return NULL;
}




/*将记录按姓名字母升序插入链表*/
void InsertList(struct lnode *list, struct lnode *n)
{
    struct lnode *p = list;

    while (p->next != NULL && strcmp((p->next->data).name, (n->data).name) < 0)
    {
        p = p->next;
    }
    n->next = p->next;
    p->next = n;
}

/*释放整个链表空间*/
void FreeList(struct lnode *list)
{
    struct lnode *p = list;
    while (p->next != NULL)
    {
        p = p->next;
        free(list);
        list = p;
    }
    free(p);
}


/*显示表头*/
void DisplayTableHead(void)
{
    printf("%-10s %c %s %13s\n", "NAME", 'S', "TEL", "EMAIL");
}

/*显示一条记录*/
void DisplayRecord(struct lnode *r)
{
    printf("%-10s %c %11s %s\n", (r->data).sex, (r->data).tel, (r->data).email);
}


/*显示菜单*/
void DisplayMenu(void)
{
    printf("\n----------------- AddressBook Display -------------\n");
    printf("\n1. Add\n2. Search\n3. Del\n4. Display\n0. Exit\n");
    printf("\nPlease select the function number (0-4) : ");
}