#!/usr/bin/perl

# migrate old samba2 smb.conf settings to new samba3 setup
# as well as merge local configuration settings
# Dec 3 2003 Stew Benedict <sbenedict@mandrakesoft.com>
# revised Jan 6 2004 - dropping some parameters
# revised Feb 11 2004 - don't try to process a config a second time

# check command line arguments
my $numargs = @ARGV;
if ($numargs lt 1) {
	print "useage: smb-migrate test|test-commit|commit\n";
	exit(1);
}

# define some variables
my $user_parms = 0;
my $new_conf_file = "/etc/samba/smb.conf";
my @new_conf;
my $merged_conf_file = "/etc/samba/smb.conf";
my $merge_comment = "# *** merged from original smb.conf: ***\n";
my $uncomment_comment = "# *** uncommented from original smb.conf: ***\n";
my $unique_comment = "# *** unique added from original smb.conf: ***\n";
my @merge_log;
my $log_file = "/var/log/samba/smb-migrate.log";
my $to_merge = "/etc/samba/smb.conf.tomerge";

if ($ARGV[0] eq "test" || $ARGV[0] eq "test-commit") {
	$to_merge = "smb.conf"; 
	$log_file = "smb-migrate.log";
	$merged_conf_file = "smb.conf.merged";
}

# if the file has already been processed, don't do it again
my $processed = `grep -c 'original smb.conf: ***' $to_merge`;
if ($processed > 0) {
	`cp $to_merge $new_conf_file`;
	print "Already processed, aborting.\n";	
	exit 0;
}
	
# get the stripped, uncommented data from old smb.conf
my @old_conf = `grep -v "^#" $to_merge | grep -v "^;" | grep -v "^\$"` or die;

# use a clean config file as a starting point
`cp /usr/share/samba/smb.conf.clean $new_conf_file` if $ARGV[0] !~ /test/;

# and the whole new conf file we're going to merge with
my @new_conf_org = `cat $new_conf_file` or die;

mlog("Data to change/add in standard sections of smb.conf:\n\n");

sub mlog {
	my (@dstring) = @_;
	if ($ARGV[0] eq "test") {
		print "@dstring";
	} else {
		push @merge_log, @dstring;
	}
}

sub merge_conf {
	my ($header, $new_value) = @_;
	my @parmlist = split " = ", $new_value;
	my $match = 0;
	my $comment = '';
	$comment = $unique_comment if $continuation = 0;
	$continuation = 1;
	
	# find the header in question
	$index = 0;
	foreach (@new_conf_org) {
 		if (/^\[$header\]|;\[$header\]|^; \[$header\]|^\[$header\$\]|;\[$header\$\]|^; \[$header\$\]/) {
			# restore print$
			$header = "print" . '$' if $header eq "print";
			# if the header is commented, remove the comment
			if (/^;\[|^#\[|^; \[/) {
				my $entry = $_;
				@new_conf_org[$index] =~ s/^;|^; |^#//g;
				mlog("uncomment: $header line $index: $entry -> @new_conf_org[$index]");
				splice(@new_conf_org, $index, 0, $uncomment_comment);
				$index++
			}
			$start_loc = $index;
#			print "[$header]: $start_loc\n";
			last;
		}
		$index++
	}
	
	my $elements = @new_conf_org;

	# walk through this header's entries, update as needed
	for ($i = $start_loc + 1; $i < $elements; $i++) {
		# if we hit a new header, may be commented - bail out
		my $is_header = @new_conf_org[$i];
		$is_header =~ s/^ |\t|\n//;
		if ($is_header =~ /^\[|;\[|#\[/) { 
#			print "new header: $is_header at $i\n";
			if ($match == 0) {
				# it's possible the parameter is continued across multiple lines
				$continuation = 0 if  $new_value !~ /\\$/;
				# completely new entry, try to place it under the correct header
#				print "new entry for [$header]: $new_value\n";
				mlog("unique: $header line $last_index: $new_value");
				splice(@new_conf_org, $last_index + 1, 0, $comment, $new_value);
				$last_index++;$last_index++;
			}
			return;
		}

		# some syntax changes
		if ($new_value =~ /winbind/) {
			$old_value = $new_value; 
			$new_value =~ s/winbind/idmap/;
			mlog("syntax: $header: $old_value -> $new_value");
		}

		# partial match, decide whether to add or replace
		if (@new_conf_org[$i] =~ /@parmlist[0]/) {
			if (@new_conf_org[$i] !~ /^;|^#/) {
				if (@new_conf_org[$i] ne $_) { 
					mlog("update: $header line $i: @new_conf_org[$i] -> $new_value");
					@new_conf_org[$i] = ";" . $new_conf_org[$i];
					splice(@new_conf_org, $i + 1, 0, $merge_comment, $new_value);
#					$match = 1;
				}
				$match = 1;
			} else {
				# is it really a definition or just a comment?
				if (@new_conf_org[$i] =~ / = /) {
					# commented in new config, add the old entry
					mlog("add: $header line $i: @new_conf_org[$i] -> $new_value");
					splice(@new_conf_org, $i + 1, 0, $merge_comment, $new_value);
					$i++;$i++;
					$match = 1;
				}
			}
#			$match = 1 if $new_value eq @new_conf_org[$i];
			$last_index = $i;
			return if ($match eq 1);
			$match = 0;
		}	
	}
	return;
}

foreach (@old_conf) {
	# check for section headers
	if (/^\[/) {
		# standard headers?
		if (!/^\[global\]|^\[homes\]|^\[netlogon\]|^\[Profiles\]|^\[printers\]|^\[print\$\]|^\[pdf-generator\]/) {
			# non-standard - add to new config
			$user_parms = 1;
			push (@new_conf, $_);
		} else {
			$user_parms = 0;
			chop;
			$header = $_;
			s/\[|\]|\$//g;
			$bare_header = $_;
		}
	} else {
		# non-standard - add to new config
		if ($user_parms == 1) {
			push (@new_conf, $_);
		} else {
			# now we're working with standard settings
			# update new config with values if they differ or are commented out
			# translate any old nomenclature to the new style
			# may still be some commented lines buried
			# throw those out and try to merge into new config
			if (!/^[ ]+#|^[ ]+;|^#|^;/) {
#				print "$header: $_\n";
				merge_conf($bare_header, $_);
			}
		}
	}
}

# write the user config data to new smb.conf

mlog("\nNew data for smb.conf:\n\n");
mlog("@new_conf");

if ($ARGV[0] eq "commit" || $ARGV[0] eq "test-commit") {
	local *NEWCONF;
	open(NEWCONF, "> $merged_conf_file");
	print NEWCONF @new_conf_org;
	print NEWCONF @new_conf;
	close NEWCONF;
	local *LOGFILE;
	open(LOGFILE, "> $log_file");
	print LOGFILE @merge_log;
	close LOGFILE
}