#include<stdio.h>
#include<stdlib.h>
#include<conio.h>
#include<string.h>
struct infor {
	char ID[50];
	char NAME[50];
	float PRICE;
	long  NUMBER;
}g[1000],m[1000],x;
struct inf {
	char id[50];
	char name[50];
	float price;
	long  number;
}c;
 FILE *p;
 void menu_s();
 void input();
 void output();
 void check();
 void updata();
 void add();
 void dele();
 int len();
  int len2();
 int main()
 {
 	system("cls");//清屏
	int n;
	menu_s();
	scanf("%d",&n);
	while(n)
	{
	system("cls");
	
		switch(n)
		{
			case 1:
			input() ;break;
			case 2:
			output();break;
			case 3:
			updata();break;
			case 4:
			check();break;
			case 5:
			 return 0;
		} 
		getch();
		menu_s();
		scanf("%d",&n);
	 }
}
	 void menu_s ()
{
	printf("----------------------------\n"); 
	printf("***********主菜单***********\n");
	printf("*********1:商品入库*********\n");
	printf("*********2:商品出库*********\n");
	printf("*********3:更新库存*********\n");
	printf("*********4:查询库存*********\n");
	printf("*********5:退出系统*********\n");
	printf("*********请输入选项*********\n");
	printf("----------------------------\n"); 
}
void input()
{    
     int i=0,s;
	char next[2]="y";
	p=fopen("1.txt","wb+");
	if(p==NULL)
	{
		printf("打开文件失败\n");
		fclose(p);
		exit(0);
	}
	while(strcmp(next,"y")==0||strcmp(next,"Y")==0)
	{   
		printf("\n请输入商品编号\n");
		scanf("%s",g[i].ID );
		printf("\n请输入商品名称\n");
		scanf("%s",&g[i].NAME );
		printf("\n请输入商品价格\n");
	    scanf("%f",&g[i].PRICE );
	    printf("\n请输入商品数量\n");
	    scanf("%d",&g[i].NUMBER );
		fwrite(&g[i],sizeof(struct infor),1,p);/*向文件写入数据*/
		printf("\n继续输入（y(Y)/n(N)）\n");
		fflush(stdin);//清空缓存区。
		i++;
	
		scanf("%s",next);
	}
	fclose(p);	 
}
int len()//读取当前文件长度 
{    int z=0;
	p=fopen("1.txt","r+");
	if(p==NULL)
	{
		printf("打开文件失败\n");
		exit(1);
    }
     rewind(p);//将文件指针移至文件开头。
      while(!feof(p))
     {
    if((fread(&g[z],sizeof(struct infor),1,p))==1);
    z++;
    }
    fclose(p);
    return z-1;
}
int len2()//读取当前文件长度 
{    int z=0;
    FILE *fp;
	fp=fopen("3.txt","r+");
	if(fp==NULL)
	{
		printf("打开文件失败\n");
		exit(1);
    }
     rewind(fp);//将文件指针移至文件开头。
      while(!feof(fp))
     {
    if((fread(&c,sizeof(struct inf),1,fp))==1);
    z++;
    }
    fclose(fp);
    return z;
}
   void check()
{   
    int i,s=0;
	long length;
	p=fopen("1.txt","rb+");
	if(p==NULL)
	{
		printf("打开文件失败\n");
		exit(1);
    }
     printf("\n----------------------------------------------------\n商品列表\n----------------------------------------------------\n");
     printf("编号\t\t品名\t\t价格\t\t数量\n");
     rewind(p);//将文件指针移至文件开头。
    s=len();
    rewind(p);
    fread(g,sizeof(struct infor),s,p);
    for(i=0;i<s;i++)
    printf("%-10s\t%s\t\t%.1f\t\t%ld\n",g[i].ID ,g[i].NAME ,g[i].PRICE,g[i].NUMBER  );
    printf("----------------------------------------------------\n");
	fclose(p);
}
 void output()
{
	FILE *p,*fp;
	char a[50],next[2]="y";
	int i,j,l,sum=0,num=0,s;
	p=fopen("1.txt","rb+");
	fp=fopen("3.txt","wb+");
	while(strcmp(next,"y")==0||strcmp(next,"Y")==0)
	{
	 l=len();
	printf("请输入售出的商品名称\n");
	scanf("%s",&a[50]);
	 	  for(i=0;i<l;i++)
	   {
	   	fseek(p,sizeof(struct infor)*(i),0);
	   	fscanf(p,"%s%s%d%d",&c.id ,&c.name ,&c.price ,&c.number );//printf("%-10s\t%s\t\t%.1f\t\t%ld\n",c.id ,c.name ,c.price ,c.number);
	}
	fclose(fp);
     printf("\n继续输入（y(Y)/n(N)）\n");
	 scanf("%s",next);
}    
    s=len2();
	fp=fopen("3.txt","rb+");
	printf("\n----------------------------------------------------\n商品列表\n----------------------------------------------------\n");
     for(i=0;i<s;i++)
	   {
	   	fseek(fp,sizeof(struct inf)*(i),0);
	   	fscanf(fp,"%s%s%d%d",&c.id ,&c.name ,&c.price ,&c.number );
	   	num+=c.price ;
	   	printf("%-10s\t%s\t\t%.1f\t\t%ld\n",c.id ,c.name ,c.price ,c.number);
	   	printf("总销售额：\t\t\t\t\t%d\n",num);
	   	}
	   	fclose(fp);
    printf("----------------------------------------------------");
}

void updata()
{   
    int a;
	printf("\n请选择：1删除商品信息；2添加商品信息\n");
	scanf("%d",&a);
	switch(a)
{  
  case 1:dele();break;
  case 2:add();break;
}
}
void add()
{	 
    FILE *P;
    int i=0;
    char next[2]="y";
		while(strcmp(next,"y")==0||strcmp(next,"Y")==0)
	{   
		printf("\n请输入商品编号\n");
		scanf("%s",&g[i].ID );
		printf("\n请输入商品名称\n");
		scanf("%s",&g[i].NAME );
		printf("\n请输入商品价格\n");
	    scanf("%f",&g[i].PRICE );
	    printf("\n请输入商品数量\n");
	    scanf("%d",&g[i].NUMBER );
		
			p=fopen("1.txt","ab");
	if(p==NULL)
	{
		printf("打开文件失败\n");
		exit(0);
	}
	fwrite(&g[i],sizeof(struct infor),1,p);/*向文件写入数据*/
	fclose(p);
		printf("\n继续输入（y(Y)/n(N)）\n");		
		scanf("%s",next);
	}
	    
 } 
void dele()
{
	FILE *p,*fp;
	char r[50];
	int i=0,j,l;
	l=len();
	printf("请输入将要删除的商品名称\n");
	scanf("%s",&r);
	p=fopen("1.txt","rb+");
	fp=fopen("2.txt","wb+");
		  for(i=0;i<l;i++)
	   {
	   	fseek(p,sizeof(struct infor)*(i),0);
	   	fscanf(p,"%s%s%d%d",&c.id ,&c.name ,&c.price ,&c.number );
	   	if(strcmp(r,c.name )!=0)
	   	{
		   fwrite(&c,sizeof(struct inf),1,fp);
		   }
		 
}     
    rewind(fp);
	fclose(p);
	p=fopen("1.txt","wb+"); 
    for(i=0;i<l-1;i++)
   {
   	fseek(fp,sizeof(struct inf)*(i),0);
    fscanf(fp,"%s%s%d%d",&x.ID  ,&x.NAME,&x.PRICE ,&x.NUMBER );
    fwrite(&x,sizeof(struct infor),1,p);
   }
   	fclose(p);
	fclose(fp);
}