#!/work/bin/nawk -f
# ------------------------------------------------
# format.idx -- prepare formatted index
# Author:  Dale Dougherty
# Version 1.1   7/10/90
# 
# input should be PRIMARY:SECONDARY:PAGE:VOLUME
# Args:  FMT = 0 (default) format for screen
#        FMT = 1 output with troff macros
#        MACDIR = pathname of index troff macro file 
# ------------------------------------------------
BEGIN {		FS = ":"
		upper = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
		lower = "abcdefghijklmnopqrstuvwxyz" 
}

# Output initial macros if troff FMT 
NR == 1 && FMT == 1 {
		if (MACDIR)
			printf (".so %s/indexmacs\n", MACDIR) 
		else
			printf (".so indexmacs\n") 
		printf (".Se \"\" \"Index\"\n") 
		printf (".XC\n") 
} # end of NR == 1
 

# main routine - apply to all lines
# determine which fields to output
{
   # convert octal colon to "literal" colon 
   # make sub for each field, not $0, so that fields are not parsed
	gsub(/\\72/, ":", $1)
	gsub(/\\72/, ":", $2)
	gsub(/\\72/, ":", $3)

   # assign field to variables
	PRIMARY = $1
	SECONDARY = $2
	TERTIARY = ""
	PAGE = $3
	if (NF == 2) {
		SECONDARY = ""
		PAGE = $2
	}
   # Look for empty fields to determine what to output
	if (! PRIMARY) {  
		if (! SECONDARY) {
			TERTIARY = $3
			PAGE = $4	
			if (FMT == 1)
				printf (".XF 3 \"%s", TERTIARY)
			else
				printf ("  %s", TERTIARY)
		}
		else
			if (FMT == 1)
				printf (".XF 2 \"%s", SECONDARY)
			else
				printf ("  %s", SECONDARY)
	}
	else { # if primary entry exists
	
	     # extract first char of primary entry
		firstChar = substr($1, 1, 1)
	     # see if it is in lower string.
		char = index(lower, firstChar) 
	     # char is an index to lower or upper letter 
		if (char == 0)  {
		# if char not found, see if it is upper
			char = index(upper, firstChar)
			if (char == 0)
				char = prevChar
		}
		# if new char, then start group for new letter of alphabet
		if (char != prevChar) {
			if (FMT == 1)
				printf(".XF A \"%s\"\n", substr(upper, char, 1))
			else
				printf("\n\t\t%s\n", substr(upper, char, 1))
			prevChar = char
		}
		# now output primary and secondary entry
		if (FMT == 1)
			if (SECONDARY)
				printf (".XF 1 \"%s\" \"%s", PRIMARY, SECONDARY)
			else
				printf (".XF 1 \"%s\" \"", PRIMARY)
		else
			if (SECONDARY)
				printf ("%s, %s", PRIMARY, SECONDARY)
			else
				printf ("%s", PRIMARY)
	}
	
   # if page number, call pageChg to replace "^" with ":"
   # for multi-volume page lists.
	if (PAGE) {
		if (FMT == 1) {
			# added to omit comma after bold entry
			if (! SECONDARY && ! TERTIARY)
				printf ("%s\"", pageChg(PAGE))
			else
				printf (", %s\"", pageChg(PAGE))
		}
		else
			printf (", %s", pageChg(PAGE))
	}
	else if (FMT == 1)
		printf("\"")
	
	printf ("\n")

} # End of main routine

# Supporting function

# pageChg -- convert "^" to ":" in list of volume^page 
#	Arg: pagelist -- list of numbers 

function pageChg(pagelist) {
	 gsub(/\^/, ":", pagelist)
	 if (FMT == 1) {
		gsub(/[1-9]+\*/, "\\fB&\\fP", pagelist)
		gsub(/\*/, "", pagelist)
	}
	return pagelist
}# End of pageChg function