#include
#include
#pragma comment(lib,"ws2_32.lib")

//定義檔案型別對應的content-tyoe
struct doc_type{
	char *suffix;
	char *type;
};

//檔案
struct doc_type file_type[]=
{
	{"html",  "text/html"},
	{"gif",   "imag/gif"},
	{"jpeg",  "imag/jpeg"},
	{NULL,    NULL}
};

//響應首部內容
char *http_res_hdr_tmp1="HTTP/1.1 200 OK \r\nServer:Jiangwei's Server<0.1>\r\n"
                        "Accept-Ranges:bytes\r\nContent-Length:%d\r\nConnection:close\r\n"
						"Content-Type:%s\r\n\r\n";

//通過字尾，查詢到對應的content-type
char *http_get_type_by_suffix(const char *suffix)
{
	struct doc_type *type;
	for(type=file_type;type->suffix;type++)
	{
		if(strcmp(type->suffix,suffix)==0)
			return type->type;
	}
	return NULL;
}


//解析客戶端傳送過來的請求
void http_parse_request_cmd(char *buf,int buflen,char *file_name,char *suffix)
{
	int length=0;
	char *begin,*end,*bias;

	//查詢URL開始位置
	begin=strchr(buf,' ');
	begin++;
    
	//查詢URL結束位置
	end=strchr(begin,' ');
	*end=0;
    
	bias=strrchr(begin,'/');
	length=end-bias;

	//找到檔名開始的位置
	if((*bias=='/')||(*bias=='\\'))
	{
		bias++;
		length--;
	}

	//得到客戶端請求的檔名
	if(length>0)
	{
		memcpy(file_name,bias,length);
		file_name[length]=0;

		begin = strchr(file_name,'.');
		if(begin)
			strcpy(suffix,begin+1);
	}
}

int http_send_response(SOCKET soc,char *buf,int buf_len)
{
	int read_len,file_len,hdr_len,send_len;
	char *type;
	char read_buf[1024];
	char http_header[1024];
	char file_name[256]="index.html";
	char suffix[16]="html";
	FILE *res_file;

	//通過解析URL，得到檔名
	http_parse_request_cmd(buf,buf_len,file_name,suffix);

	//開啟檔案
	res_file=fopen(file_name,"rb+");

	if(res_file==NULL)
	{
		printf("[Web]檔案:%s 不存在!\n",file_name);
		return 0;
	}

	//計算檔案大小
	fseek(res_file,0,SEEK_END);
	file_len=ftell(res_file);
	fseek(res_file,0,SEEK_SET);

	//獲得檔案content-type
	type=http_get_type_by_suffix(suffix);
    
	if(type==NULL)
	{
		printf("[Web]沒有相關的檔案型別!\n");
		return 0;
	}
    
	//構造響應首部，加入檔案長度，content-type資訊
	hdr_len=sprintf(http_header,http_res_hdr_tmp1,file_len,type);
	send_len=send(soc,http_header,hdr_len,0);
	
	if(send_len==SOCKET_ERROR)
	{
		fclose(res_file);
		printf("[Web]傳送失敗，錯誤:%d\n",WSAGetLastError());
		return 0;
	}

	//傳送檔案
	do
	{
		read_len=fread(read_buf,sizeof(char),1024,res_file);
		if(read_len>0)
		{
			send_len=send(soc,read_buf,read_len,0);
			file_len-=read_len;
		}
	}while((read_len>0) && (file_len>0));
	fclose(res_file);
    return 1;
}
int main(){
	WSADATA wsa;
	WSAStartup(MAKEWORD(2,0),&wsa);
	SOCKET serversoc,acceptsoc;
	SOCKADDR_IN serveraddr;
	SOCKADDR_IN fromaddr;
	char Recv_buf[1024];
	int from_len=sizeof(fromaddr);
	int result;
	int Recv_len;

	//建立socket
	serversoc = socket(AF_INET,SOCK_STREAM,0);
	if(serversoc==INVALID_SOCKET)
    {
		printf("[Web]建立套接字失敗!");
		return -1;
	}

	//初始化伺服器IP,Port
	serveraddr.sin_family = AF_INET;
	serveraddr.sin_port = htons(8080);
	serveraddr.sin_addr.s_addr = htonl(INADDR_ANY);

	//繫結socket
	result=bind(serversoc,(SOCKADDR *)&serveraddr,sizeof(serveraddr));
	if(result==SOCKET_ERROR)
	{
		closesocket(serversoc);
		printf("[Web]繫結套接字失敗!");
		return -1;
	}
    
	//監聽socket請求
	result = listen(serversoc,3);
	printf("[Web]伺服器正在執行.....\n");

	while(1)
	{
		//接收請求
		acceptsoc = accept(serversoc,(SOCKADDR *)&fromaddr,&from_len);
		if(acceptsoc==INVALID_SOCKET)
		{
			printf("[Web]接收請求失敗!");
			break;
		}
		printf("[Web]連線來自 IP:  %s  Port:  %d  \n",inet_ntoa(fromaddr.sin_addr),ntohs(fromaddr.sin_port));
		
		//接收來自客戶端的請求
        Recv_len=recv(acceptsoc,Recv_buf,1024,0);
		if(Recv_len==SOCKET_ERROR)
		{
			printf("[Web]接收資料失敗!");
			break;
		}
		Recv_buf[Recv_len]=0;
		//向客戶端傳送響應資料
		result = http_send_response(acceptsoc,Recv_buf,Recv_len);

		closesocket(acceptsoc);
	}

	closesocket(serversoc);
	WSACleanup();

	return 0;
}