/*---------------------------------------------------------------------------
   
   File name 	:	pafs.c
   Author 		:	Nicolas Devillard
   Created on	:	February 1999
   Description	:	paf format I/O

 *--------------------------------------------------------------------------*/

/*
	$Id: pafs.c,v 1.3 2001/12/03 13:11:31 ndevilla Exp $
	$Author: ndevilla $
	$Date: 2001/12/03 13:11:31 $
	$Revision: 1.3 $
*/

/*---------------------------------------------------------------------------
   								Includes
 ---------------------------------------------------------------------------*/

#include "pafs.h"
#include "userid.h"
#include "t_iso8601.h"
#include "strlib.h"

#ifdef _ECLIPSE_
#include "comm.h"
#include "static_sz.h"
#else
#include "e_error.h"
#define ASCIILINESZ	1024
#endif

#define PAF_MAGIC       "PAF.HDR.START"
#define PAF_MAGIC_SZ    13


/*---------------------------------------------------------------------------
  							Function codes
 ---------------------------------------------------------------------------*/


/*-------------------------------------------------------------------------*/
/**
  @name		paf_print_header
  @memo		Open a new PAF file, output a default header.
  @param	filename	Name of the file to create.
  @param	paf_id		PAF identificator.
  @param	paf_desc	PAF description.
  @return	Opened file pointer.
  @doc

  This function creates a new PAF file with the requested file name.
  If another file already exists with the same name, it will be
  overwritten (if the file access rights allow it).

  A default header is produced according to the VLT DICB standard. You
  need to provide an identificator (paf_id) of the producer of the
  file. Typically, something like "ISAAC/zero_point".

  The PAF description (paf_desc) is meant for humans. Typically,
  something like "Zero point computation results".

  This function returns an opened file pointer, ready to receive more
  data through fprintf's. The caller is responsible for fclose()ing
  the file.
 */
/*--------------------------------------------------------------------------*/

FILE * paf_print_header(
	char *  filename,
	char *	paf_id,
	char *	paf_desc)
{
	FILE * paf ;
	
	if ((paf=fopen(filename, "w"))==NULL) {
		e_error("cannot create PAF file [%s]", filename);
		return NULL ;
	}
	fprintf(paf, "PAF.HDR.START         ;# start of header\n");
	fprintf(paf, "PAF.TYPE              \"pipeline product\" ;\n");
	fprintf(paf, "PAF.ID                \"%s\"\n", paf_id);
	fprintf(paf, "PAF.NAME              \"%s\"\n", filename);
	fprintf(paf, "PAF.DESC              \"%s\"\n", paf_desc);
	fprintf(paf, "PAF.CRTE.NAME         \"%s\"\n", get_login_name()) ;
	fprintf(paf, "PAF.CRTE.DAYTIM       \"%s\"\n", get_datetime_iso8601()) ;
	fprintf(paf, "PAF.LCHG.NAME         \"%s\"\n", get_login_name()) ;
	fprintf(paf, "PAF.LCHG.DAYTIM       \"%s\"\n", get_datetime_iso8601()) ;
	fprintf(paf, "PAF.CHCK.CHECKSUM     \"\"\n");
	fprintf(paf, "PAF.HDR.END           ;# end of header\n");
	fprintf(paf, "\n");
	return paf ;
}



/*-------------------------------------------------------------------------*/
/**
  @name		paf_query
  @memo		Query a PAF file for a value.
  @param	filename	Name of the PAF to query.
  @param	key			Name of the key to query.
  @return	1 pointer to statically allocated string, or NULL.
  @doc

  This function parses a PAF file and returns the value associated to a
  given key, as a pointer to an internal statically allocated string.
  Do not try to free or modify the contents of the returned string!

  If the key is not found, this function returns NULL.
 */
/*--------------------------------------------------------------------------*/

char * paf_query(char * filename, char * key)
{
	static char value[ASCIILINESZ];
	FILE	*	paf ;
	char		line[ASCIILINESZ+1];
	char		val[ASCIILINESZ+1];
	char		head[ASCIILINESZ+1];
	int			found ;
	int			len ;

	/* Check inputs */
	if (filename==NULL || key==NULL) return NULL ;

	/* Check PAF validity */
	if (is_paf_file(filename)!=1) {
		e_error("not a PAF file: [%s]", filename);
		return NULL ;
	}

	/* Open file and read it */
	paf = fopen(filename, "r");
	if (paf==NULL) {
		e_error("opening [%s]", filename);
		return NULL ;
	}
	
	found = 0 ;
	while (fgets(line, ASCIILINESZ, paf)!=NULL) {
		sscanf(line, "%[^ ]", head);
		if (!strcmp(head, key)) {
			/* Get value */
			sscanf(line, "%*[^ ] %[^;]", value);
			found ++ ;
			break ;
		}
	}
	if (!found) return NULL ;
	
	/* Remove trailing blanks */
	strcpy(val, strcrop(value));
	/* Get rid of possible quotes */
	len = strlen(val);
	if (val[0]=='\"' && val[len-1]=='\"') {
		strncpy(value, val+1, len-2);
		value[len-2]=(char)0;
	} else {
		strcpy(value, val);
	}
	return value ;
}


/*-------------------------------------------------------------------------*/
/**
  @name		is_paf_file
  @memo		returns 1 if file is in PAF format, 0 else
  @param	filename name of the file to check
  @return	int 0, 1, or -1
  @doc
  Returns 1 if the file name corresponds to a valid PAF file. Returns
  0 else. If the file does not exist, returns -1. Validity of the PAF file 
  is checked with the presence of PAF.HDR.START at the beginning
 */
/*--------------------------------------------------------------------------*/
int is_paf_file(char *filename)
{
	FILE	*	fp ;
	int			is_paf ;
	char		line[ASCIILINESZ] ;
	
	if (filename==NULL) return -1 ;

	/* Initialize is_paf */
	is_paf = 0 ;

	/* Open file */
	if ((fp = fopen(filename, "r"))==NULL) {
		e_error("cannot open file [%s]", filename) ;
		return -1 ;
	}

	/* Parse file */
	while (fgets(line, ASCIILINESZ, fp) != NULL) {
		if (line[0] != '#') {
			if (!strncmp(line, PAF_MAGIC, PAF_MAGIC_SZ)) is_paf = 1 ;
			(void)fclose(fp) ;
			return is_paf ;
		}
	}

	(void)fclose(fp) ;
	return is_paf ;
}