#include <stdio.h>
#include <unistd.h>
#include <string.h>
#include <errno.h>
#include<netdb.h> //hostent
#ifdef USE_OPENSSL
#include <openssl/ssl.h>
#include <openssl/err.h>
#endif
#include <sys/time.h>
#include <ifaddrs.h>
#include <arpa/inet.h>

#include "utils.h"
#include "handle.h"

#include "ws.h"
static void ws_gen_mask_key(ws_msg_header_t * header)
{
	int r = rand();
	header->mask_key[0]  = (r >> 24) & 0xFF;
	header->mask_key[1]  = (r >> 16) & 0xFF;
	header->mask_key[2]  = (r >> 8) & 0xFF;
	header->mask_key[3]  = r & 0xFF;
}
/**
* Read a frame header
* based on this header, we'll decide
* the appropriate handle for frame data
*/
ws_msg_header_t * ws_read_header(void* client)
{
	
	uint8_t byte = 0;
	uint8_t bytes[8];
	ws_msg_header_t* header = (ws_msg_header_t*) malloc(sizeof(*header));
	
	// get first byte
	if(antd_recv(client, &byte, sizeof(byte)) <0) goto fail;
	if(BITV(byte,6) || BITV(byte,5) || BITV(byte,4)) goto fail;// all RSV bit must be 0
	
	//printf("FIN: %d, RSV1: %d, RSV2: %d, RSV3:%d, opcode:%d\n", BITV(byte,7), BITV(byte,6), BITV(byte,5), BITV(byte,4),(byte & 0x0F) );
	// find and opcode
	header->fin = BITV(byte,7);
	header->opcode = (byte & 0x0F);
	
	// get next byte
	if(antd_recv(client, &byte, sizeof(byte)) <0) goto fail;
	
	//printf("MASK: %d paylen:%d\n", BITV(byte,7), (byte & 0x7F));
	// check mask bit, should be 1
	header->mask = BITV(byte,7);
	/*if(!BITV(byte,7))
	{
		// close the connection with protocol error
		ws_close(client, 1002);
		goto fail;
	}*/
	// get the data length of the frame
	int len = (byte & 0x7F);
	if(len <= 125)
	{
		header->plen = len;
	} else if(len == 126)
	{
		if(antd_recv(client,bytes, 2*sizeof(uint8_t)) <0) goto fail;
		header->plen = (bytes[0]<<8) + bytes[1];
		
	} else
	{
		//read only last 4 byte
		if(antd_recv(client,bytes, 8*sizeof(uint8_t)) <0) goto fail;
		header->plen = (bytes[4]<<24) + (bytes[5]<<16) + (bytes[6] << 8) + bytes[7] ;
	}
	//printf("len: %d\n", header->plen);
	// last step is to get the maskey
	if(header->mask)
		if(antd_recv(client,header->mask_key, 4*sizeof(uint8_t)) <0) goto fail;
	//printf("key 0: %d key 1: %d key2:%d, key3: %d\n",header->mask_key[0],header->mask_key[1],header->mask_key[2], header->mask_key[3] );
	
	// check wheather it is a ping or a close message
	// process it and return NULL
	//otherwise return the header
	//return the header
	switch(header->opcode){
		case WS_CLOSE: // client requests to close the connection
		// send back a close message
		ws_send_close(client,1000,header->mask?0:1);
		//goto fail;
		break;
		
		case WS_PING: // client send a ping
		// send back a pong message
		ws_pong(client,header, header->mask?0:1 );
		break;
		
		default: break;
	}
	return header;
	
	fail:
	free(header);
	return NULL;
	
}
/**
* Read data from client
* and unmask data using the key
*/
int ws_read_data(void* client, ws_msg_header_t* header, int len, uint8_t* data)
{
	// if len  == -1 ==> read all remaining data to 'data';
	if(header->plen == 0) return 0;
	int dlen = (len==-1 || len > (int)header->plen)?(int)header->plen:len;
	if((dlen = antd_recv(client,data, dlen)) <0) return -1;
	header->plen = header->plen - dlen;
	// unmask received data
	if(header->mask)
		for(int i = 0; i < dlen; ++i)
			data[i] = data[i]^ header->mask_key[i%4];
	data[dlen] = '\0';
	return dlen;
}
void _send_header(void* client, ws_msg_header_t header)
{
	uint8_t byte = 0;
	uint8_t bytes[8];
	for(int i=0; i< 8; i++) bytes[i] = 0;
	//first byte |FIN|000|opcode|
	byte = (header.fin << 7) + header.opcode;
	//printf("BYTE: %d\n", byte);
	antd_send(client, &byte, 1);
	// second byte, payload length
	// mask may be 0 or 1
	//if(header.mask == 1)
	//	printf("Data is masked\n");
	if(header.plen <= 125)
	{
		byte =  (header.mask << 7) + header.plen;
		antd_send(client, &byte, 1);
	}
	else if(header.plen < 65536) // 16 bits
	{
		byte = (header.mask << 7) + 126;
		bytes[0] = (header.plen) >> 8;
		bytes[1] = (header.plen) & 0x00FF;
		antd_send(client, &byte, 1);
		antd_send(client, &bytes, 2);
	}
	else // > 16 bits
	{
		byte =  (header.mask << 7) + 127;
		bytes[4] = (header.plen) >> 24;
		bytes[5] = ((header.plen)>>16) & 0x00FF;
		bytes[6] = ((header.plen)>>8) & 0x00FF;
		bytes[7] = (header.plen) & 0x00FF;
		antd_send(client, &byte, 1);
		antd_send(client, &bytes, 8);
	}
	// send mask key
	if(header.mask)
	{
		antd_send(client, header.mask_key,4);
	}
}
/**
* Send a frame to client
*/
void ws_send_frame(void* client, uint8_t* data, ws_msg_header_t header)
{
	uint8_t * masked;
	masked = data;
	if(header.mask)
	{
		ws_gen_mask_key(&header);
		masked = (uint8_t*) malloc(header.plen);
		for(int i = 0; i < (int)header.plen; ++i)
			masked[i] = data[i]^ header.mask_key[i%4];
	}
	_send_header(client, header);
	if(header.opcode == WS_TEXT)
		antd_send(client,(char*)masked,header.plen);
	else
		antd_send(client,(uint8_t*)masked,header.plen);
	if(masked && header.mask)
		free(masked);
}
/**
* send a text data frame to client
*/
void ws_send_text(void* client, const char* data,int mask)
{
	ws_msg_header_t header;
	header.fin = 1;
	header.opcode = WS_TEXT;
	header.mask = mask;
	header.plen = strlen(data);
	//_send_header(client,header);
	//send(client, data, header.plen,0);
	ws_send_frame(client,(uint8_t*)data,header);
}
/**
* send a single binary data fram to client
* not tested yet, but should work
*/
void ws_send_binary(void* client, uint8_t* data, int l, int mask)
{
	ws_msg_header_t header;
	header.fin = 1;
	header.opcode = WS_BIN;
	header.plen = l;
	header.mask = mask;
	ws_send_frame(client,data, header);
	//_send_header(client,header);
	//send(client, data, header.plen,0);
}
/*
* send a file as binary data
*/
void ws_send_file(void* client, const char* file, int mask)
{
	uint8_t buff[1024];
	FILE *ptr;
	ptr = fopen(file,"rb");
	if(!ptr)
	{
		ws_send_close(client,1011,mask);
		return;
	}

	ws_msg_header_t header;
	size_t size;
	int first_frame = 1;
	//ws_send_frame(client,buff,header);
	header.mask = mask;
	while(!feof(ptr))
	{
		size = fread(buff,1,1024,ptr);
		if(feof(ptr))
			header.fin = 1;
		else
			header.fin = 0;
		// clear opcode
		if(first_frame)
		{
			header.opcode = WS_BIN;
			first_frame = 0;
		}
		else
			header.opcode = 0;
		header.plen = size;
		//printf("FIN: %d OC:%d\n", header.fin, header.opcode);
		ws_send_frame(client,buff,header);
	}
	fclose(ptr);
}
/**
* Not tested yet
* but should work
*/
void ws_pong(void* client, ws_msg_header_t* oheader, int mask)
{
	ws_msg_header_t pheader;
	pheader.fin = 1;
	pheader.opcode = WS_PONG;
	pheader.plen = oheader->plen;
	pheader.mask = mask;
	uint8_t *data = (uint8_t*)malloc(oheader->plen);
	if(!data) return;
	
	if(ws_read_data(client, oheader, pheader.plen,data) == -1)
	{
		ERROR("Cannot read ping data %d", pheader.plen);
		free(data);
		return;
	}
	ws_send_frame(client,data,pheader);
	free(data);
	//_send_header(client, pheader);
	//send(client, data, len, 0);
}
void ws_ping(void* client, const char* echo, int mask)
{
	ws_msg_header_t pheader;
	pheader.fin = 1;
	pheader.opcode = WS_PING;
	pheader.plen = strlen(echo);
	pheader.mask = mask;
	ws_send_frame(client,(uint8_t*)echo,pheader);
}
/*
* Not tested yet, but should work
*/
void ws_send_close(void* client, unsigned int status, int mask)
{
	//printf("CLOSED\n");
	ws_msg_header_t header;
	header.fin = 1;
	header.opcode = WS_CLOSE;
	header.plen = 2;
	header.mask=mask;
	uint8_t bytes[2];
	bytes[0] = status >> 8;
	bytes[1] = status & 0xFF;
	/*if(mask)
	{
		// XOR itself
		header.mask_key[0] = bytes[0];
		header.mask_key[1] = bytes[1];
		bytes[0] = bytes[1] ^ bytes[1];
	}*/
	ws_send_frame(client,bytes,header);
	//_send_header(client, header);
	//send(client,bytes,2,0);
}
int ip_from_hostname(const char * hostname , char* ip)
{
    struct hostent *he;
    struct in_addr **addr_list;
    int i;    
    if ( (he = gethostbyname( hostname ) ) == NULL) 
    {
        // get the host info
        ERROR("gethostbyname:%s",strerror(errno));
        return -1;
    }
    addr_list = (struct in_addr **) he->h_addr_list;
     
    for(i = 0; addr_list[i] != NULL; i++) 
    {
        //Return the first one;
        strcpy(ip , inet_ntoa(*addr_list[i]) );
        return 0;
    }
    return -1;
}

/*
send a request
*/
int request_socket(const char* ip, int port)
{
	int sockfd;
	struct sockaddr_in dest;
	
	// time out setting
	struct timeval timeout;
	timeout.tv_sec = CONN_TIME_OUT_S;
	timeout.tv_usec = 0;//3 s
	if ( (sockfd = socket(AF_INET, SOCK_STREAM, 0)) < 0 )
	{
		ERROR("Socket: %s", strerror(errno));
		return -1;
	}
	if (setsockopt (sockfd, SOL_SOCKET, SO_RCVTIMEO, (char *)&timeout,sizeof(timeout)) < 0)
	    ERROR("setsockopt failed:%s", strerror(errno));

    if (setsockopt (sockfd, SOL_SOCKET, SO_SNDTIMEO, (char *)&timeout,sizeof(timeout)) < 0)
        ERROR("setsockopt failed:%s",strerror(errno));
	/*struct linger lingerStruct;
    lingerStruct.l_onoff = 0;  // turn lingering off for sockets
    setsockopt(sockfd, SOL_SOCKET, SO_LINGER, &lingerStruct, sizeof(lingerStruct));*/
	
    bzero(&dest, sizeof(dest));
    dest.sin_family = AF_INET;
    dest.sin_port = htons(port);
    if ( inet_aton(ip, &dest.sin_addr) == 0 )
    {
		perror(ip);
		close(sockfd);
		return -1;
    }
	if ( connect(sockfd, (struct sockaddr*)&dest, sizeof(dest)) != 0 )
	{
		close(sockfd);
		ERROR("Connect:%s",strerror(errno));
		return -1;
	}
	return sockfd;
}

void ws_client_close(ws_client_t* wsclient)
{
	antd_close(wsclient->antdsock);

#ifdef USE_OPENSSL
	if(wsclient->ssl_ctx)
	{
		SSL_CTX_free(wsclient->ssl_ctx);
		FIPS_mode_set(0);
		// DEPRECATED: CONF_modules_unload(1);
		EVP_cleanup();
		EVP_PBE_cleanup();
		// DEPRECATED:ENGINE_cleanup();
		CRYPTO_cleanup_all_ex_data();
		// DEPRECATED: ERR_remove_state(0);
		ERR_free_strings();
	}
#endif
}

//this is for the client side, not use for now
int ws_client_connect(ws_client_t* wsclient, port_config_t pcnf)
{
    char ip[100];
	int stat = ip_from_hostname(wsclient->host,ip);
	if(stat == -1)
		return -1;
	int sock = request_socket(ip, pcnf.port);
	if(sock <= 0)
	{
		ERROR("Cannot request socket");
		return -1;
	}
	// will be free
	wsclient->antdsock->sock = sock;
	wsclient->antdsock->z_status = 0;
	wsclient->antdsock->last_io = time(NULL);
	wsclient->antdsock->zstream = NULL;
#ifdef USE_OPENSSL
	if(pcnf.usessl)
	{
		SSL_library_init();
		SSL_load_error_strings();
		ERR_load_crypto_strings();
    	OpenSSL_add_ssl_algorithms();
		const SSL_METHOD *method;
		unsigned long ssl_err = 0;
		method = SSLv23_client_method();
		ssl_err = ERR_get_error();
		if(!method)
		{
			ERROR("SSLv23_method: %s", ERR_error_string(ssl_err, NULL));
			return -1;
		}
		wsclient->ssl_ctx = SSL_CTX_new(method);
		ssl_err = ERR_get_error();
    	if (!wsclient->ssl_ctx) {
			ERROR("SSL_CTX_new: %s", ERR_error_string(ssl_err, NULL));
			return -1;
		}
		// configure the context
#if defined(SSL_CTX_set_ecdh_auto)
    	SSL_CTX_set_ecdh_auto(wsclient->ssl_ctx, 1);
#else
    	SSL_CTX_set_tmp_ecdh(wsclient->ssl_ctx, EC_KEY_new_by_curve_name(NID_X9_62_prime256v1));
#endif
		SSL_CTX_set_options(wsclient->ssl_ctx, SSL_OP_NO_TLSv1|SSL_OP_NO_TLSv1_1|SSL_OP_NO_SSLv2|SSL_OP_NO_TICKET);
		// set the cipher suit
		const char* suit = wsclient->ciphersuit?wsclient->ciphersuit:PREFERRED_WS_CIPHERS;
		//const char* suit = "AES128-SHA";
		if (SSL_CTX_set_cipher_list(wsclient->ssl_ctx, suit) != 1)
		{
			ssl_err = ERR_get_error();
			// TODO Close the context
			ERROR("SSL_CTX_set_cipher_list: %s", ERR_error_string(ssl_err, NULL));
			return -1;
		}

		if(wsclient->sslcert && wsclient->sslkey)
		{
			if (SSL_CTX_use_certificate_file(wsclient->ssl_ctx,wsclient->sslcert, SSL_FILETYPE_PEM) <= 0) {
				ssl_err = ERR_get_error();
				ERROR("SSL_CTX_use_certificate_file: %s", ERR_error_string(ssl_err, NULL));
				return -1;
			}
			if(wsclient->sslpasswd)
				SSL_CTX_set_default_passwd_cb_userdata(wsclient->ssl_ctx,(void*)wsclient->sslpasswd);
			if (SSL_CTX_use_PrivateKey_file(wsclient->ssl_ctx,wsclient->sslkey, SSL_FILETYPE_PEM) <= 0) {
				ssl_err = ERR_get_error();
				ERROR("SSL_CTX_use_PrivateKey_file: %s", ERR_error_string(ssl_err, NULL));
				return -1;
			}
			if (SSL_CTX_check_private_key(wsclient->ssl_ctx) == 0) {
				ssl_err = ERR_get_error();
				ERROR("SSL_CTX_check_private_key: %s", ERR_error_string(ssl_err, NULL));
				return -1;
			}
		}
		//

		// validate 
		if(wsclient->verify_location)
		{
			SSL_CTX_set_verify(wsclient->ssl_ctx, SSL_VERIFY_PEER, NULL);
        	SSL_CTX_set_verify_depth(wsclient->ssl_ctx, 5);
			if(!SSL_CTX_load_verify_locations(wsclient->ssl_ctx, wsclient->verify_location, NULL))
			{
				ssl_err = ERR_get_error();
				// TODO Close the context
				ERROR("SSL_CTX_load_verify_locations: %s", ERR_error_string(ssl_err, NULL));
				return -1;
			}
		}
		else
		{
			SSL_CTX_set_verify(wsclient->ssl_ctx, SSL_VERIFY_NONE, NULL);	
		}

		wsclient->antdsock->ssl = (void*)SSL_new(wsclient->ssl_ctx);
		if(!wsclient->antdsock->ssl)
		{
			ssl_err = ERR_get_error();
			ERROR("SSL_new: %s", ERR_error_string(ssl_err, NULL));
			return -1;
		}
		SSL_set_fd((SSL*)wsclient->antdsock->ssl, wsclient->antdsock->sock);
		int stat, ret;
		ERR_clear_error();
		while( (ret = SSL_connect(wsclient->antdsock->ssl)) <= 0)
		{
			stat = SSL_get_error(wsclient->antdsock->ssl, ret);
			switch (stat)
			{
				case SSL_ERROR_WANT_READ:
				case SSL_ERROR_WANT_WRITE:
				case SSL_ERROR_NONE:
					continue;
				default:
					ERR_print_errors_fp(stderr);
					ERROR("Error performing SSL handshake %d", stat);
					return -1;
			}
		}
	}
#endif
	return 0;
}




int ws_open_handshake(ws_client_t* client)
{
	char buf[MAX_BUFF];
	// now send ws request handshake 
   	sprintf(buf, CLIENT_RQ,client->resource,client->host);
	//printf("Send %s\n", buf);
    int size = antd_send(client->antdsock, buf, strlen(buf));
    if(size != (int)strlen(buf))
    {
        ERROR("Cannot send request \n");
        return -1;
    }
    // now verify if server accept the socket 
	size  = read_buf(client->antdsock,buf,MAX_BUFF);
	char* token;
    int done = 0;
	while (size > 0 && strcmp("\r\n",buf))
	{
		char* line = buf;
		token = strsep(&line,":");
		trim(token,' ');
		if(token != NULL &&strcasecmp(token,"Sec-WebSocket-Accept") == 0)
		{
			token = strsep(&line,":");
			trim(token,' ');
			trim(token,'\n');
			trim(token,'\r');
            if(strcasecmp(token, SERVER_WS_KEY) == 0)
            {
                //LOG("Handshake sucessfull\n");
                done = 1;
            } else
            {
                ERROR("WS handshake, Wrong key %s vs %s",token,SERVER_WS_KEY);
                return -1;
            }
		} 
		//if(line) free(line);
		size  = read_buf(client->antdsock,buf,MAX_BUFF);
	}
    if(done) 
		return 0;
    return -1;
}
char* get_ip_address()
{
	struct ifaddrs* addrs;
	getifaddrs(&addrs);
	struct ifaddrs* tmp = addrs;
	char* ip;
	while (tmp) 
	{
	    if (tmp->ifa_addr && tmp->ifa_addr->sa_family == AF_INET)
	    {
			struct sockaddr_in *pAddr = (struct sockaddr_in *)tmp->ifa_addr;
	        ip = inet_ntoa(pAddr->sin_addr);
			if(strcmp(ip,"127.0.0.1") != 0) 
				return ip;
	    }
	    tmp = tmp->ifa_next;
	}
	freeifaddrs(addrs);
	return "127.0.0.1";
}