#!/usr/bin/perl

# Copyright (c) 1996
# Silicon Graphics, Inc.
#
# Permission to use, copy, modify, distribute and sell this software
# and its documentation for any purpose is hereby granted without fee,
# provided that the above copyright notice appear in all copies and
# that both that copyright notice and this permission notice appear
# in supporting documentation.  Silicon Graphics makes no
# representations about the suitability of this software for any
# purpose.  It is provided "as is" without express or 
# implied warranty.

$non_numeric_base = "generic/object";
$numeric_base = "generic/numeric";
$generic_type = "generic";
$generic_package = "GENERIC";
@files = ("BinaryOperator",    "Modification",      "Sorting",
	  "BinaryPredicate",   "Numeric",           "UnaryOperator",
	  "Generator",         "Predicate",         "VoidFunction",
	  "Inspection",        "Range",             "Equals",
	  );
$extension = ".java";

$word_count = 0;
while ($_ = shift) {
    if (/^-/) {
	if (/^-n$/)
	  { $is_numeric_type = 1; }
	else
	  { goto print_usage; }
    }
    else 
      { $words[$word_count++] = $_; }
}

if ($word_count < 1 || $word_count > 2)
    { goto print_usage; }
$type_name = $words[0];
$package_name = $words[$word_count - 1];
$source_directory = $is_numeric_type ? $numeric_base : $non_numeric_base;
$dest_directory = $package_name;

if (-d $dest_directory) {
    print "Performing instantiation in directory $dest_directory, ";
    print "which already exists.\n";
}
elsif (-e $dest_directory) {
    print "$0: Error:  The package $package_name must be instantiated in the\n";
    print "directory $dest_directory.  A non-directory file of that name\n";
    print "already exists.\n";
    exit 1;
}
else {
    print "Creating directory $dest_directory for instantiation.\n";
    mkdir $dest_directory, 0777 || die "Error: couldn't create directory.\n";
}

while ($base_name = pop(@files)) {
    $file_name = $base_name . $extension;
    $source_file = $source_directory . "/" . $file_name;
    $dest_file   = $dest_directory. "/" . $file_name;

    print "  Instantiating $file_name...\n";
    if (-e $dest_file) {
	$backup_file = $dest_file . ".bak";
	print "    $dest_file already exists.\n    Saving it in $backup_file.\n";
	unlink $backup_file if -e $backup_file;
	rename $dest_file, $backup_file;
    }

    $in_ok = open IN, $source_file;
    $out_ok = open OUT, ">" . $dest_file;

    if (!$in_ok) {
	print "    Instantiation failed.  Can't open $source_file for reading.\n";
    }
    elsif (!$out_ok) {
	print "    Instantiation failed.  Can't open $dest_file for writing.\n";
    }
    else {
	while(<IN>) {
	    s/$generic_package/$package_name/g;
	    s/$generic_type/$type_name/g;
	    print OUT;
	}
    }

    close IN;
    close OUT;
}
print "Done.\n";
exit 0;


print_usage:
    die "Usage: $0 [-n] type_name [package_name]\n";