/*
 * main.c
 *
 *  Beej's Guide to Network Programming
 *  http://beej.us/guide/bgnet/output/html/multipage/index.html
 *  http://beej.us/guide/bgnet/output/html/multipage/clientserver.html
 *
 *  MySQL and C
 *  http://zetcode.com/db/mysqlc/
 *  http://www.kitebird.com/mysql-book/ch06-3ed.pdf
 *
 *  Omnik message info found here:
 *  Written in PHP
 *  https://github.com/micromys/Omnik
 *  Written in Python
 *  https://github.com/Woutrrr/Omnik-Data-Logger/blob/master/InverterMsg.py
 *  Written in C
 *  https://github.com/arjenv/omnikstats
 *
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <sys/socket.h>
#include <netdb.h>
#include <arpa/inet.h>
#include <netinet/in.h>
#include <errno.h>
#include <unistd.h>
#include <sys/wait.h>
#include <signal.h>
#include <time.h>
#include <mysql/mysql.h>

#define OMNIKPORTAL_PULL "8899"
#define PORT_LISTEN "8989"
#define BACKLOG 10


FILE * fp;

MYSQL *conn;
MYSQL_RES *res;
MYSQL_ROW row;

unsigned char mysql_enabled = 0;
char mysql_host[100] = "";
char mysql_user[32] = "omniklistener";
char mysql_pass[32] = "";
char mysql_db[100] = "energyportal";
unsigned int mysql_port = 3306;
unsigned char csv_enabled = 0;
char csvfile[250] = "";
unsigned char silent = 0;


void doChildProcess(int fd_client);
void printMessage(unsigned char *message, int length);

void sigchld_handler(int s){
	while(waitpid(-1, NULL,WNOHANG) > 0);
}

// get sockaddr, IPv4 or IPv6:
void *get_in_addr(struct sockaddr *sa)
{
    if (sa->sa_family == AF_INET) {
        return &(((struct sockaddr_in*)sa)->sin_addr);
    }

    return &(((struct sockaddr_in6*)sa)->sin6_addr);
}
int startswith(const char *prefix, const char *string){
	size_t lenstring = strlen(string);
	size_t lenprefix = strlen(prefix);
	if(lenstring < lenprefix){
		return 0;
	}
	else{
		return (strncmp(string,prefix,lenprefix) == 0);
	}
}

int main(int argc, char *argv[]){
	int fd_server;	//Listening socket
	int fd_client;  //Client connected socket
	struct addrinfo hints, *res, *p;
	struct sockaddr_storage their_addr;
	struct sigaction sa;
	int status;
	char ipstr[INET6_ADDRSTRLEN];
	socklen_t addr_size;
	char s[INET6_ADDRSTRLEN];
	pid_t pid;


	//Loop through command line arguments
	int i = 0;
	for(i = 0; i < argc; i++){
		if(startswith("--mysql-host=",argv[i])){
			strcpy(mysql_host,argv[i]+strlen("--mysql-host="));
		}
		if(startswith("--mysql-user=",argv[i])){
			strcpy(mysql_user,argv[i]+strlen("--mysql-user="));
		}
		if(startswith("--mysql-pass=",argv[i])){
			strcpy(mysql_pass,argv[i]+strlen("--mysql-pass="));
		}
		if(startswith("--mysql-db=",argv[i])){
			strcpy(mysql_db,argv[i]+strlen("--mysql-db="));
		}
		if(startswith("--mysql-port=",argv[i])){
			sscanf(argv[i]+strlen("--mysql-port="),"%d",&mysql_port);
		}
		if(startswith("--csv-file=",argv[i])){
			strcpy(csvfile,argv[i]+strlen("--csv-file="));
		}
		if(startswith("--silent",argv[i])){
			silent = 1;
		}
	}

	//When --mysql-host is filled, then enable mysql export
	if(strlen(mysql_host) > 0){
		mysql_enabled = 1;
	}
	//When --csv-file is filled, then enable csv export
	if(strlen(csvfile) > 0){
		csv_enabled = 1;
	}


	//Print out active configuration
	printf("OmnikListenerTCP\n");
	printf(" MySQL enabled : %d\n",mysql_enabled);
	if(mysql_enabled){
		printf(" MySQL host    : %s\n",mysql_host);
		printf(" MySQL port    : %d\n",mysql_port);
		printf(" MySQL user    : %s\n",mysql_user);
		//Maybe hide password? ;)
		//printf(" MySQL pass    : %s\n",mysql_pass);
		printf(" MySQL db      : %s\n",mysql_db);
	}
	printf(" CSV enabled   : %d\n",csv_enabled);
	if(csv_enabled){
		printf(" CSV file      : %s\n",csvfile);
	}




	memset(&hints, 0, sizeof hints);
	hints.ai_family = AF_UNSPEC;
	hints.ai_socktype = SOCK_STREAM;
	hints.ai_flags = AI_PASSIVE;

	if((status = getaddrinfo(NULL, PORT_LISTEN, &hints, &res))!=0){
		fprintf(stderr, "getaddrinfo: %s\n", gai_strerror(status));
		return 2;
	}

	for(p = res; p != NULL; p=p->ai_next){
		void *addr;
		char *ipver;

		if(p->ai_family == AF_INET){
			struct sockaddr_in *ipv4 = (struct sockaddr_in *)p->ai_addr;
			addr = &(ipv4->sin_addr);
			ipver = "IPv4";
		}
		else{
			struct sockaddr_in6 *ipv6 = (struct sockaddr_in6 *)p->ai_addr;
			addr = &(ipv6->sin6_addr);
			ipver = "IPv6";
		}
		inet_ntop(p->ai_family, addr, ipstr, sizeof ipstr);
		//printf(" %s: %s\n",ipver,ipstr);
	}

	fd_server = socket(res->ai_family, res->ai_socktype, res->ai_protocol);

	if(fd_server == -1){
		perror("socket");
		return 3;
	}
	else{
		printf("Socket opened %d\n",fd_server);
	}


	if(bind(fd_server, res->ai_addr, res->ai_addrlen) == -1){
		perror("bind");
		return 4;
	}

	if(listen(fd_server,BACKLOG) == -1){
		perror("listen");
		return 5;
	}

	sa.sa_handler = sigchld_handler;
	sigemptyset(&sa.sa_mask);
	sa.sa_flags = SA_RESTART;
	if(sigaction(SIGCHLD, &sa, NULL) == -1){
		perror("sigaction");
		exit(1);
	}

	printf("server: waiting for connections...\n");

	while(1){
		addr_size = sizeof their_addr;
		fd_client = accept(fd_server, (struct sockaddr *)&their_addr, &addr_size);
		if(fd_client == -1){
			perror("accept");
			continue;
		}
		else{
			printf("Socket accepted %d\n",fd_client);
		}

		inet_ntop(their_addr.ss_family,
			get_in_addr((struct sockaddr *)&their_addr),
			s, sizeof s);

		printf("server: get connection from %s\n",s);

		pid = fork();
		if(pid == 0){
			close(fd_server); //child doesn't need the listener
			doChildProcess(fd_client);
		}
		close(fd_client);
	}



	return 0;
}

void doChildProcess(int fd_client)
{
	int numbytes;
	unsigned char recvbuf[512];

	if((numbytes = recv(fd_client, recvbuf, 511, 0)) == -1){
		perror("recv");
		exit(1);
	}
	printf("client: received bytes %d \n",numbytes);

	printMessage(recvbuf,numbytes);


	close(fd_client);
	exit(0);
}

void printMessage(unsigned char *message, int length){
	time_t timer;
	char timebuffer[26];
	struct tm* tm_info;
	int i = 0;
	unsigned char byte;

	char p_id[17];
	short p_temp;
	long p_etoday;
	long p_etotal;
	long p_htotal;
	short p_vpv1;
	short p_vpv2;
	short p_vpv3;
	short p_ipv1;
	short p_ipv2;
	short p_ipv3;
	short p_vac1;
	short p_vac2;
	short p_vac3;
	short p_iac1;
	short p_iac2;
	short p_iac3;
	short p_fac1;
	short p_fac2;
	short p_fac3;
	short p_pac1;
	short p_pac2;
	short p_pac3;

	time(&timer);
	tm_info = localtime(&timer);

	if(length < 143)
	{
		printf("Message to short? Do not process.\n");
		return;
	}

	for(i = 0; i < length; i++){
		byte = message[i];
		printf("%02X ",byte);
		if((i + 1) % 8 == 0){
			printf("\n");
		}
	}
	printf("\n");

	if(message[0] == 0x68 && message[1] == 0x81 && message[2] == 0x41 && message[3] == 0xB0){
		//OK
	}
	else{
		printf("Header does not match hex: 68 81 41 B0\n");
		printf("Skip message");
		return;
	}




	for(i = 0; i < length; i++){
		byte = message[i];

		//Byte 15, start of SerialNumber
		if(i >= 15 && i <= 30){
			p_id[i-15]=byte;
		}

		//Byte 31-32 contain temperature
		if(i == 31){
			p_temp = 0;
			p_temp = byte << 8;
		}
		if(i == 32){
			p_temp = p_temp | byte;
		}

		//Byte 33-34 PV 1 input voltage
		if(i == 33){
			p_vpv1 = 0;
			p_vpv1 = byte << 8;
		}
		if(i == 34){
			p_vpv1 = p_vpv1 | byte;
		}

		//Byte 35-36 PV 2 input voltage
		if(i == 35){
			p_vpv2 = 0;
			p_vpv2 = byte << 8;
		}
		if(i == 36){
			p_vpv2 = p_vpv2 | byte;
		}

		//Byte 37-38 PV 3 input voltage
		if(i == 37){
			p_vpv3 = 0;
			p_vpv3 = byte << 8;
		}
		if(i == 38){
			p_vpv3 = p_vpv3 | byte;
		}

		//Byte 39-40 PV 1 input current
		if(i == 39){
			p_ipv1 = 0;
			p_ipv1 = byte << 8;
		}
		if(i == 40){
			p_ipv1 = p_ipv1 | byte;
		}

		//Byte 41-42 PV 2 input current
		if(i == 41){
			p_ipv2 = 0;
			p_ipv2 = byte << 8;
		}
		if(i == 42){
			p_ipv2 = p_ipv2 | byte;
		}

		//Byte 43-44 PV 3 input current
		if(i == 43){
			p_ipv3 = 0;
			p_ipv3 = byte << 8;
		}
		if(i == 44){
			p_ipv3 = p_ipv3 | byte;
		}

		//Byte 45-46 AC output current phase 1
		if(i == 45){
			p_iac1 = 0;
			p_iac1 = byte << 8;
		}
		if(i == 46){
			p_iac1 = p_iac1 | byte;
		}
		//Byte 47-48 AC output current phase 2
		if(i == 47){
			p_iac2 = 0;
			p_iac2 = byte << 8;
		}
		if(i == 48){
			p_iac2 = p_iac2 | byte;
		}
		//Byte 49-50 AC output current phase 3
		if(i ==49){
			p_iac3 = 0;
			p_iac3 = byte << 8;
		}
		if(i == 50){
			p_iac3 = p_iac3 | byte;
		}

		//Byte 51-52 AC output voltage phase 1
		if(i == 51){
			p_vac1 = 0;
			p_vac1 = byte << 8;
		}
		if(i == 52){
			p_vac1 = p_vac1 | byte;
		}
		//Byte 53-54 AC output voltage phase 2
		if(i == 53){
			p_vac2 = 0;
			p_vac2 = byte << 8;
		}
		if(i == 54){
			p_vac2 = p_vac2 | byte;
		}
		//Byte 55-56 AC output voltage phase 3
		if(i == 55){
			p_vac3 = 0;
			p_vac3 = byte << 8;
		}
		if(i == 56){
			p_vac3 = p_vac3 | byte;
		}

		//Byte 57-58 AC output ??what?? phase 1
		if(i == 57){
			p_fac1 = 0;
			p_fac1 = byte << 8;
		}
		if(i == 58){
			p_fac1 = p_fac1 | byte;
		}
		//Byte 59-60 AC output power phase 1
		if(i == 59){
			p_pac1 = 0;
			p_pac1 = byte << 8;
		}
		if(i == 60){
			p_pac1 = p_pac1 | byte;
		}
		//Byte 61-62 AC output ??what?? phase 2
		if(i == 61){
			p_fac2 = 0;
			p_fac2 = byte << 8;
		}
		if(i == 62){
			p_fac2 = p_fac2 | byte;
		}
		//Byte 63-64 AC output power phase 2
		if(i == 63){
			p_pac2 = 0;
			p_pac2 = byte << 8;
		}
		if(i == 64){
			p_pac2 = p_pac2 | byte;
		}
		//Byte 63-64 AC output ??what?? phase 3
		if(i == 65){
			p_fac3 = 0;
			p_fac3 = byte << 8;
		}
		if(i == 66){
			p_fac3 = p_fac3 | byte;
		}
		//Byte 67-68 AC output power phase 3
		if(i == 67){
			p_pac3 = 0;
			p_pac3 = byte << 8;
		}
		if(i == 68){
			p_pac3 = p_pac3 | byte;
		}


		//Byte 69-70 contain total kwh of today
		if(i == 69){
			p_etoday = 0;
			p_etoday = byte << 8;
		}
		if(i == 70){
			p_etoday = p_etoday | byte;
		}

		//Byte 71-74 contain total kwh
		if(i == 71){
			p_etotal = 0;
			p_etotal = p_etotal | (byte << 24);
		}
		if(i == 72){
			p_etotal = p_etotal | (byte << 16);
		}
		if(i == 73){
			p_etotal = p_etotal | (byte << 8);
		}
		if(i == 74){
			p_etotal = p_etotal | byte;
		}

		//Byte 75-78 contain hours online
		if(i == 75){
			p_htotal = 0;
			p_htotal = p_htotal | (byte << 24);
		}
		if(i == 76){
			p_htotal = p_htotal | (byte << 16);
		}
		if(i == 77){
			p_htotal = p_htotal | (byte << 8);
		}
		if(i == 78){
			p_htotal = p_htotal | byte;
		}
	}

	p_id[16] = 0;

	if(!silent){
		strftime(timebuffer, sizeof(timebuffer), "%Y-%m-%d %H:%M:%S", tm_info);
		printf("Time    : %s \n", timebuffer);
		printf("Serial  : %s     \n", p_id);
		printf("Temp    : %f     \n", ((double) p_temp / 10));
		printf("E-Today : %f kWh \n", ((double) p_etoday / 100));
		printf("E-Total : %f kWh \n", ((double) p_etotal / 10));
		printf("H-Total : %ld H   \n", p_htotal);

		printf("PV 1 U  : %f V \n", ((double) p_vpv1 / 10));
		printf("PV 1 I  : %f A \n", ((double) p_ipv1 / 10));
		printf("PV 2 U  : %f V \n", ((double) p_vpv2 / 10));
		printf("PV 2 I  : %f A \n", ((double) p_ipv2 / 10));
		printf("PV 3 U  : %f V \n", ((double) p_vpv3 / 10));
		printf("PV 3 I  : %f A \n", ((double) p_ipv3 / 10));


		printf("AC1 U   : %f V \n", ((double) p_vac1 / 10));
		printf("AC1 I   : %f A \n", ((double) p_iac1 / 10));
		printf("AC1 ?   : %f ? \n", ((double) p_fac1 / 100));
		printf("AC1 P   : %d W \n", p_pac1);
		printf("AC2 U   : %f V \n", ((double) p_vac2 / 10));
		printf("AC2 I   : %f A \n", ((double) p_iac2 / 10));
		printf("AC2 ?   : %f ? \n", ((double) p_fac2 / 100));
		printf("AC2 P   : %d W \n", p_pac2);
		printf("AC3 V   : %f V \n", ((double) p_vac3 / 10));
		printf("AC3 I   : %f A \n", ((double) p_iac3 / 10));
		printf("AC3 ?   : %f ? \n", ((double) p_fac3 / 100));
		printf("AC3 P   : %d W \n", p_pac3);

		strftime(timebuffer, sizeof(timebuffer), "%Y-%m-%d %H:%M:%S", tm_info);
		printf("%s,%s,%f,%f,%f,%ld,%f,%f,%f,%f,%f,%f,%f,%f,%f,%d,%f,%f,%f,%d,%f,%f,%f,%d\n",
			timebuffer,
			p_id,
			((double) p_temp / 10),
			((double) p_etoday / 100),
			((double) p_etotal / 10),
			p_htotal,
			((double) p_vpv1 / 10),
			((double) p_ipv1 / 10),
			((double) p_vpv2 / 10),
			((double) p_ipv2 / 10),
			((double) p_vpv3 / 10),
			((double) p_ipv3 / 10),
			((double) p_vac1 / 10),
			((double) p_iac1 / 10),
			((double) p_fac1 / 100),
			p_pac1,
			((double) p_vac2 / 10),
			((double) p_iac2 / 10),
			((double) p_fac2 / 100),
			p_pac2,
			((double) p_vac3 / 10),
			((double) p_iac3 / 10),
			((double) p_fac3 / 100),
			p_pac3);
	} //END !silent

	if(csv_enabled){
		fp = fopen(csvfile,"a");
		if(fp == NULL){
			perror("fopen");
		}
		else{
			printf("Opened file for appending\n");
			strftime(timebuffer, sizeof(timebuffer), "%Y-%m-%d %H:%M:%S", tm_info);
			fprintf(fp, "%s,%s,%f,%f,%f,%ld,%f,%f,%f,%f,%f,%f,%f,%f,%f,%d,%f,%f,%f,%d,%f,%f,%f,%d\n",
				timebuffer,
				p_id,
				((double) p_temp / 10),
				((double) p_etoday / 100),
				((double) p_etotal / 10),
				p_htotal,
				((double) p_vpv1 / 10),
				((double) p_ipv1 / 10),
				((double) p_vpv2 / 10),
				((double) p_ipv2 / 10),
				((double) p_vpv3 / 10),
				((double) p_ipv3 / 10),
				((double) p_vac1 / 10),
				((double) p_iac1 / 10),
				((double) p_fac1 / 100),
				p_pac1,
				((double) p_vac2 / 10),
				((double) p_iac2 / 10),
				((double) p_fac2 / 100),
				p_pac2,
				((double) p_vac3 / 10),
				((double) p_iac3 / 10),
				((double) p_fac3 / 100),
				p_pac3);
			fflush(fp);
			fclose(fp);
		}
	}

	if(mysql_enabled){
		//Try to write to mysql
		conn = mysql_init(NULL);
		if(conn == NULL){
			perror("mysql_init");
		}
		else{

			if(!mysql_real_connect(conn,mysql_host,mysql_user,mysql_pass,mysql_db,mysql_port,NULL,0)){
				fprintf(stderr, "%s\n",mysql_error(conn));
			}
			else{
				char stmt_buf[1024];
				sprintf(stmt_buf,""
					"INSERT INTO `omnikdata` ("
					"`inverterid`,`moment`,`temperature`,`p_today`,`p_total`,`h_total`,"
					"`pv1_u`,`pv1_i`,`pv2_u`,`pv2_i`,`pv3_u`,`pv3_i`,"
					"`ac1_u`,`ac1_i`,`ac1_f`,`ac1_p`,"
					"`ac2_u`,`ac2_i`,`ac2_f`,`ac2_p`,"
					"`ac3_u`,`ac3_i`,`ac3_f`,`ac3_p`) "
					" VALUES ("
					"'%s',NOW(),%f,%f,%f,%ld,%f,%f,%f,%f,%f,%f,%f,%f,%f,%d,%f,%f,%f,%d,%f,%f,%f,%d);",
					p_id,
					((double) p_temp / 10),
					((double) p_etoday / 100),
					((double) p_etotal / 10),
					p_htotal,
					((double) p_vpv1 / 10),
					((double) p_ipv1 / 10),
					((double) p_vpv2 / 10),
					((double) p_ipv2 / 10),
					((double) p_vpv3 / 10),
					((double) p_ipv3 / 10),
					((double) p_vac1 / 10),
					((double) p_iac1 / 10),
					((double) p_fac1 / 100),
					p_pac1,
					((double) p_vac2 / 10),
					((double) p_iac2 / 10),
					((double) p_fac2 / 100),
					p_pac2,
					((double) p_vac3 / 10),
					((double) p_iac3 / 10),
					((double) p_fac3 / 100),
					p_pac3);


				int nQueryResult = mysql_query(conn,stmt_buf);
				if (nQueryResult > 0){
					fprintf(stdout,"%s\n",mysql_error(conn));
				}
				else{

				}

				//res = mysql_use_result(conn);

				//while((row = mysql_fetch_row(res)) != NULL){
				//	printf("Database: %s\n",row[0]);
				//	//int dumpresult = system("")
				//}

				//mysql_free_result(res);
				mysql_close(conn);

			} //END mysql_real_connect
		} //END mysql_init
	} //END mysql_enabled
}