// log_any.c
// $Id: log_any.c 124 2011-09-11 16:05:51Z csherwood $

// Testing using standard library calls to write to a file
// Developing UNSAFE signal interupt handler
//
//  requires one argument- 
//    the configuration file name- format expected port#_instid_baud.conf
//
//  has a function that just adds the Moxa time, since serialByteRead() gets parts of
//  a logical data message, we only want to add the time to the entire line, once read
//
//   csherwood@usgs.gov, emontgomery@usgs.gov, July-Aug 2011

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include <signal.h>
#include "serial.h"
#include "moxadevice.h"
#include <unistd.h>
#include <sys/time.h>

#define MAX_FNAME_SIZE 255

// Global variables or structure for passing clean-up info to signal interrupt handler?
FILE *fdp, *fdp_log, *fdp_cfg, *fdp_data; /* file stream pointer for stdio library calls */
int   fds,  fds_log,  fds_cfg,  fds_data, fds_port; /* file descriptor for system calls */
char tmp[255], instid[12];
char bufd[1024];
char datafilename[127]="/var/sda/testdata/instrument_YYYYMMDDHHMMSS.dat";
unsigned int baud_rate=9600;
int parity=0, data_bits=8, stop_bit=1, flow;
fd_set readfds;
int tmpfd, maxfd = -1;
int portnum;

// function declarations
static void my_exit(int sig);
int tsout( FILE *fd, char *buf );

int main(int argc, char *argv[])
{
  int len, ier;
  ssize_t iw;
  char buf[255]; /* may be too small */
  char nbuf[1024];
  char logfname[255];
  time_t now, tt;
  struct tm gm, *gmp;

  unsigned int iseconds = 30;
  pid_t my_pid, parent_pid;

  // params from Sam's code to read config file
  //char tmp[300];  // name of the symlinked log file (in get_data)
  //char outarchfilename[255];  // name of the archive file (in archive)
  //char syscmdbuf[512];  // a buffer to hold system commands    
  //int serport = 99;    // the "linux" name of the port (e.g. tty0)
  char portname[30];
  unsigned int sermode, baudrate;
  int parity, databits, stopbits, flowcontrol;
  int result, nchars, tstat, knt=0;
  char str1[10], str2[10], str3[10], str4[10], str5[10], str6[10], str7[10], str8[10];
  char *p, *p2, *lastc;
  struct timeval tv;
  // Set to check every 2 seconds to see if that fixes getting YSI in 2 parts
  tv.tv_sec = 2;
  tv.tv_usec = 0;

// on dell that has an actual db9 serial port, use /dev/ttyS0
// on lenovo with just USB, not sure what is right- maybe /dev/ttyUSB0?
// on Moxa ?? /dev/ttyM0

  signal(SIGINT,my_exit);  /* terminal interuppt (e.g., ctrl-C) */
  signal(SIGTERM,my_exit); /* terminate process */

  now=time(NULL);
  gmp = gmtime(&now);
  gm = *gmp;
  my_pid = getpid();
  parent_pid = getppid();
  
  // Required argument: name of config file
  if( argc != 2 ){

    snprintf(buf,sizeof(buf),"Config file name required: argc: %2d",argc);
    ier = tsout( fdp_log, buf );
    ier = tsout( stdout, buf );
    my_exit( SIGUSR1 );
  }
  // config file name second section has the string to use in logging
  p=index(argv[1],'_');
  p2=rindex(argv[1],'_');
   nchars=(int)p2-(int)p;
   strncpy(instid,p+1, nchars-1);
  
  // open a log file with a name that includes the PID and date
  //snprintf(logfname,sizeof(logfname),"./%s_%d.log", instid, my_pid);
  // for use with cron, use absolute path to open a log file with a name that includes the PID
   snprintf(logfname,MAX_FNAME_SIZE,"/var/sda/logs/%s_%04d%02d%02d%02d%02d%02d_%06d.log",
	    instid,1900+gm.tm_year,gm.tm_mon+1,gm.tm_mday,gm.tm_hour,gm.tm_min,gm.tm_sec,(int)my_pid);

  fdp_log = fopen(logfname,"wt");
  if(fdp_log == NULL)
    {
      // Send this message to a better place? stdout and stderr?
      printf("Problem opening log file\n");
      my_exit(SIGUSR1);
    }

  // Get system fd of log file. See TLPI p. 248
  printf("System i/o file descriptor for logfile: %d\n", (fds_log = fileno(fdp_log)));

  // Log program name and PID to log file
  snprintf(buf,sizeof(buf),"%s PID : %d",argv[0],my_pid );
  ier = tsout( fdp_log, buf );
  ier = tsout( stdout, buf );

  // Open the config file (based on Sam Laney's code)
  snprintf(buf,sizeof(buf),"Config file name: %s",argv[1]);
  ier = tsout( fdp_log, buf );
  ier = tsout( stdout, buf );
    if( (fdp_cfg=fopen( argv[1], "rt")) == NULL )
      {
	snprintf(buf,sizeof(buf),"Could not open config file: %s",argv[1] );
	ier = tsout( fdp_log, buf );
	ier = tsout( stdout, buf );
	my_exit( SIGUSR1 );
      }
    else 
      {
	// read and log the header
	snprintf(buf,sizeof(buf),"Opened config file: %s",argv[1] );
	ier = tsout( fdp_log, buf );
	ier = tsout( stdout, buf );
/* config file format: 1 header line, followed by a csv list- 1 line with 8 things:
 * port #, inst_identifier, serial mode (232), baud, parity, length, stop bits, flow ctl
 * they go into str1-str8
 */
	fgets(tmp, 200, fdp_cfg);    //read header
	snprintf(buf,sizeof(buf), "conf header: %s", tmp);
	ier = tsout( fdp_log, buf );
	ier = tsout( stdout, buf );

	// read the info we use from conf file
	if (fgets(tmp, 200, fdp_cfg) == NULL){
	  // if  EOF is reached on an fgets
	  snprintf(buf,sizeof(buf),"No data in config file %s",argv[1]);
	  ier = tsout( fdp_log, buf );
	  ier = tsout( stdout, buf );
	  my_exit( SIGUSR1 );
	}
	    
	// put the config data into the right records e.g.: 4,ysi,232,9600,N,8,1,N
	result = sscanf(tmp,"%[^','],%[^','],%[^','],%[^','],%[^','],%[^','],%[^','],%[^',']",
			str1, str2, str3, str4, str5, str6, str7, str8);
	printf("%s\n%s\n%s\n%s\n%s\n%s\n%s\n%s\n", str1, str2, str3, str4,str5,str6,str7,str8);	
	portnum = atoi(str1);
	    
	// save the name string to the global variable for later use
	strcpy(portname, str2);	    
	sermode = (unsigned int) atoi(str3);
	baudrate = (unsigned int) atoi(str4);
        parity = atoi(str5);
	databits = atoi(str6);
	stopbits = atoi(str7);
	flowcontrol = atoi(str8);
	printf("File label %s port %d BAUD %d PARITY %d DATA %d STOP %d FLOW %d\n",
	       portname, portnum, baudrate, parity, databits, stopbits, flowcontrol);	
	
	if ((portnum < 0) | (portnum > 7)) {
	    snprintf(buf,sizeof(buf),"Bad value requested for serial port number.");
	    ier = tsout( fdp_log, buf );
	    ier = tsout( stdout, buf );
	    my_exit( SIGUSR1 );
	  }
    
        // close the config file
        fclose(fdp_cfg);
	snprintf(buf,sizeof(buf),"Closed config file: %s",argv[1]);
	ier = tsout( fdp_log, buf );
	ier = tsout( stdout, buf );
      }

  // Make a data file name
  // months in time structure are jan==0, so we need to add one to display correctly
  // this needs to be the full path name for when run in cron
     snprintf(datafilename,sizeof(buf),"/var/sda/data/%s/%s_%04d%02d%02d%02d%02d%02d_%06d.dat",
	    instid,instid,1900+gm.tm_year,gm.tm_mon+1,gm.tm_mday,gm.tm_hour,gm.tm_min,gm.tm_sec,(int)my_pid);
    
    // open data file
    fdp_data = fopen(datafilename,"w");
    if(fdp_data == NULL) {
     snprintf(buf,sizeof(buf),"Problem opening data file: %s",datafilename);
	ier = tsout( fdp_log, buf );
	ier = tsout( stdout, buf );
	my_exit( SIGUSR1 );
      }
    snprintf(buf,sizeof(buf),"Opened data file: %s",datafilename);
    ier = tsout( fdp_log, buf );
    ier = tsout( stdout, buf );

    // Get system fd of log file. See TLPI p. 248
    fds_data = fileno(fdp_data);
    snprintf(buf,sizeof(buf),"System fds for datafile: %2d",fds_data);
    ier = tsout( fdp_log, buf );
    ier = tsout( stdout, buf );
    snprintf(buf,sizeof(buf),"Trying to open serial port %4d",portnum);
    ier = tsout( fdp_log, buf );
    ier = tsout( stdout, buf );

    /* need something here to deal with not being able to open the port 
     * it can get into a state where SerialOpen() just doesn't return*/   
    ier = SerialOpen( portnum );
    snprintf(buf,sizeof(buf),"SerialOpen: %4d",ier);
    ier = tsout( fdp_log, buf );
    ier = tsout( stdout, buf );

    fds_port = FindFD( portnum );
    snprintf(buf,sizeof(buf),"Port open with fds_port=%4d",fds_port);
    ier = tsout( fdp_log, buf );
    ier = tsout( stdout, buf );

    /*
    // TODO: This does not work right
    if( (unsigned int)SerialGetMode( portnum ) !=sermode)
      {
	printf("Mode error!!\n");
	exit( -1);
      }
    
    if( SerialSetMode( portnum, sermode) < 0){
	printf("SerialSetMode error!!\n");
	exit(-1);
      }
    if( SerialGetMode( portnum ) !=sermode)
      {
	printf("Mode error!!\n");
	exit( -1);
      }
    */
    ier = SerialSetSpeed( portnum, baudrate);
    snprintf(buf,sizeof(buf),"Return from SerialSetSpeed: %2d",ier);
    ier = tsout( fdp_log, buf );
    ier = tsout( stdout, buf );
    
    ier = SerialSetParam( portnum, parity, databits, stopbits);
    snprintf(buf,sizeof(buf),"Return from SerialSetParam: %2d",ier);
    ier = tsout( fdp_log, buf );
    ier = tsout( stdout, buf );
    
    ier = SerialFlowControl( portnum, flow);
    snprintf(buf,sizeof(buf),"Return from SerialFlowControl: %2d",ier);
    ier = tsout( fdp_log, buf );
    ier = tsout( stdout, buf );
    
    //StartLogger();
     snprintf(buf,sizeof(buf),"Starting to log...");
    ier = tsout( fdp_log, buf );
    ier = tsout( stdout, buf );

    maxfd = fds_port;
	
    //This is where it waits until it get's something and then logs it
    while(1)
      {
	//sleep(1);
	FD_ZERO( &readfds);
	FD_SET( fds_port, &readfds);
	
	tmpfd= select( maxfd+1, &readfds, NULL, NULL, &tv);
	if( tmpfd <= 0)
	  continue;
	tstat=gettimeofday(&tv, NULL);
	if( FD_ISSET( fds_port, &readfds)){
	  len= SerialBlockRead( portnum, bufd, 1024);
	  bufd[len]= '\0';
	  
	  // put the last char of each chunk in a place available to strncmp 
	  lastc=&bufd[len-1];
	  if ( knt > 0 && fds_data != -1){  // knt > 0 avoids partial first line
	    if (strncmp(lastc,"\n",1)==0)
	      {
		// use tsout only when there's a CR at the end of buffer
		strncat(nbuf,bufd,len);
		//write( fds_data, bufd, len);
		ier = tsout(fdp_data, nbuf);
		nbuf[0]='\0';
		//fflush(nbuf);  // empty the buffer accumulating the strings
	      } else {
	      // the write makes a sensible looking data record, but it's not written
	      // as one long record, it's a series of chunks, so pre-pending moxa
	      // time doesn't make sense.  If concatenate into a buffer until a <CR>
	      // is recieved, that works better.
	      //write( fds_data, bufd, len);
	      strncat(nbuf,bufd,len);
	    }
 	  }
 	  if (strncmp(lastc,"\n",1)==0)  // count lines read
	    knt+=1;
	}  
      }
    
    // Graceful exit
    my_exit( SIGUSR1 );
}


// MY_EXIT - Clean up, close files, write to log, exit
static void my_exit(int sig)
{
  // sig is assigned by signal or passed by user

  // UNSAFE use of printf() flush(), close(), and exit()
  // TODO - Do this with async-safe calls?

  int ier;
  char buf[255];

  // (0) identify cause of exit
  switch (sig) 
    {
    case SIGINT : {
      sprintf(buf,"Caught SIGINT\n");
      break;
    }
    case SIGTERM : {
      sprintf(buf,"Caught SIGTERM\n");
      break;
    }
    case SIGUSR1 : {
      sprintf(buf,"Caught SIGUSR1\n");
      break;
    }
    default : {
    sprintf(buf,"Unknown signal\n");
    }
  }

  // Close files in order of importance:
  // (1) close serial port
  if( (ier=SerialClose(portnum)) != SERIAL_OK )
    sprintf(buf,"Problem closing serial port %d; returned %d",portnum,ier);
  sprintf(buf,"Closed serial port %d",portnum);


  // (2) close data file
  if( fdp_data != NULL ){
	write( fds_data, "\n", 1 );
    fflush(fdp_data);
    fclose(fdp_data);
  }

  // (3) close log file
  if( fdp_log != NULL ){
    ier = tsout(fdp_log,buf);
    fflush(fdp_log);
    fclose(fdp_log);
  }
  exit(0);
}

// TSOUT - prepend time stamp, print contents of buf, add CR
int tsout( FILE *fd, char *buf )
{
  //time_t t;
  struct tm gm, *gmp;
  struct timeval tv;
  int iw=1, tstat, nlen=0;
  char tbuf[255];
  char *lastc;
   
  tstat=gettimeofday(&tv,NULL);
  //gmp = gmtime(&t);
  // pointing at the tv seconds gets the time from gettimeofday, so usecs will be synched
  gmp = gmtime(&tv.tv_sec);   
  gm = *gmp; // save local copy...see TLPI p. 192
 
  snprintf(tbuf,29,"%4d %02d %02d %02d %02d %10.7f ",
 	  1900+gm.tm_year,gm.tm_mon+1,gm.tm_mday,gm.tm_hour,gm.tm_min,(gm.tm_sec+((double)tv.tv_usec/1000000)));
 
  //printf("lengths of tbuf and buf are: %d, %d.\n",  strlen(tbuf), strlen(buf));
  nlen=strlen(buf);
  if ((strlen(tbuf) + strlen(buf)) < sizeof(tbuf)-1)
  {
    strncat(tbuf,buf,nlen);
    lastc=&buf[nlen-1];
    if (strncmp(lastc,"\n",1) != 0)
      strncat(tbuf,"\n",1);
    iw = fprintf(fd,"%s",tbuf);
    fflush(fd);
  }  
  else
  {
    printf("string too long- look for error in data!\n");
    printf("%s\n",buf);
    //email manager that something's wrong
     iw=-1;
   }
}