#!/usr/local/bin/perl
#
#	Add index entries for reference to Miranda stuff

$pgm = $0;

# 	Set up boolean values
$false = 0;
$true = 1;

# 	State variables
$curLineIsPgm = $false;		# This line has program code
$prevLineWasPgm = $false;	# Previous line had program code
$endOfBlock = $false;		# Previous line blank and the one before
				# that was program
$SavedIndexEntries = '';

# 	Patterns
$PgmLinePatt = "^(\\d|\\d-|\\d-\\d)?>";

$IdPatt = "[A-Za-z][A-Za-z0-9()][A-Za-z0-9()]+";
# Less than 3 chars is uninteresting
# Include brackets for let(rec)

$PackPatt = "Pack{[^,]+,[^}]+}";
# Pack{t,a}

$ConPatt = "[A-Z][A-Za-z0-9]*";

$SchemePatt = "A|I|J|B|D|E|F|R|V|AL|SC|C|DR|AR|DE|Alt_E|DB|AB";

while (<>) {

    $curLine = $_;
    $curLineIsPgm = /$PgmLinePatt/o;
			# The o says it can compile the pattern...

    if ($endOfBlock) {
	# spit out any accum index entries

	print $SavedIndexEntries;
	if ($curLineIsPgm) { print "\n"; }

	$SavedIndexEntries = '';

    }

    if ($curLine =~ /$PgmLinePatt(.*\n)/o) {
	# Processing for program lines
		$PgmLine = $2;
		# $PgmLine now has everything after "arrow"

		# Zap comments
		$PgmLine =~ s/\|\|.*//;

		# Function and variable defns
		if ($PgmLine =~ /^ ($IdPatt) /o) {
			# Matches "index this thing" criterion.
			$SavedIndexEntries .= "\\indexDTT{$1}%\n";
		}

		# First constructor of an alg data type
		if ($PgmLine =~ /::=\s*($ConPatt)/o) {
			$SavedIndexEntries .= "\\indexDTT{$1}%\n";
		}

		# Subsequent constructors
		while ($PgmLine =~ /\|\s*($ConPatt)(.*\n)/o) {
			$SavedIndexEntries .= "\\indexDTT{$1}%\n";
			$PgmLine = $2;
		}

    } else {

		# Non program line, so just add inline index use
		# entries for things in @@ quotes
		$curLine =~ s/@($IdPatt)@/@\1@\\indexTT{\1}/go;
		$curLine =~ s/@($PackPatt)@/@\1@\\indexTT{Pack}/go;

		# Ditto for definition points of compilation schemes
		$curLine =~ s/^\\($SchemePatt)\{/\\indexD{\$\\protect\\cal \\p\1\$}\\\1\{/o;
	    }

    $endOfBlock = $prevLineWasPgm && ($curLine =~ /^\s*$/);
    $prevLineWasPgm = $curLineIsPgm;

#print "eob $endOfBlock, plp $prevLineWasPgm \n";
    print $curLine;
}