#!/usr/bin/perl -w

########################################################################
#
# prtsweep
# ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
# This is a script for removing rubbish from a CRUX port tree.
# Distributed under the terms of the GPL license.
#
# ChangeLog and author information available in the prt-utils tarball.
#
########################################################################

use strict;
use Cwd qw(cwd getcwd);
use File::Path;
our $version = "1.2.1";
our %options = ( auto => 0, dryrun => 0, rmdir => 0, pkgtoo => 0, quiet => 0 );
our @portdirs;
our $argports;

######################### main routine ################################
parse_args();
print_usage() if ((2*$argports-1)*(1-2*$options{auto}) < 0);

if ($options{auto} == 1) {
	my @basedirs = getportdirs();
	foreach my $collection (@basedirs) {
		print "====> Sweeping port collection $collection\n";
		foreach my $port (list_subdirs($collection)) {
			do_sweep($port);
		}
	}
} else {
	foreach my $port (@portdirs) {
		do_sweep($port);
	}
}

######################### subroutines #################################
sub print_usage {
	print <<EOT;
Usage: prtsweep [OPTION]... [PORTDIRS]... 

  -a     automatic mode, only valid when [PORTDIRS] are omitted
  -d     remove directories of dropped ports (signature file not found)
  -n     dry-run, don't actually delete anything
  -p     delete any built packages too
  -q     quiet mode, only print messages when files are removed

Report bugs on libera.chat #crux-devel
EOT
	exit(0);
}

sub parse_args {
	foreach my $arg (@ARGV) {
		if ($arg eq "-a") {
			$options{auto} = 1;
		} elsif ($arg eq "-d") {
			$options{rmdir} = 1;
		} elsif ($arg eq "-n") {
			$options{dryrun} = 1;
		} elsif ($arg eq "-p") {
			$options{pkgtoo} = 1;
		} elsif ($arg eq "-q") {
			$options{quiet} = 1;
		} elsif ($arg eq "--version") {
			print $version."\n";
			exit 0;
		} elsif ((-d "$arg") ||        # false for symlink to a portdir,
		       (-f "$arg/.signature")) {  # so a second test is needed
			push (@portdirs, $arg);
		} elsif (-f "$arg") {
			print "WARN: $arg is not a port directory or recognized option, ignoring.\n";
		} else {
			print_usage();
		}
	}
	$argports = @portdirs;
}

sub list_subdirs {
	my $path = shift;
	my @list;
	while ($path =~ s/\/\//\//g) {}
	$path =~ s/\/$//;

	opendir(DIR, $path) or return;
	foreach my $entry(sort(readdir(DIR))) {
		next if ( substr($entry,0,1) eq '.' );
		push (@list, "$path/$entry") if ((-d "$path/$entry")
			or (-f "$path/$entry/.signature"));
	}
	closedir(DIR);
	return @list;
}

sub parse_signature {
	my @signed = ("Pkgfile",".footprint",".signature","README","README.md",
		"pre-install","post-install",".32bit",".nostrip");
	my $sigfile = shift;
	open (FILE, $sigfile) or return @signed;
	while (<FILE>) {
		if (/^SHA256 \(.+\) =.*$/) {
			$_ =~ s/^SHA256 \((.+)\) =.*$/$1/;
			push (@signed, $_)
		}
	}
	close (FILE);
	return @signed ;
}

sub sweep {
	my $port = shift;
	while ($port =~ s/\/\//\//g) {}
	$port =~ s/\/$//;
	my @path = split /\//, $port;

	print "=======> $port\n" unless $options{quiet}==1;
	my @wanted = parse_signature ("$port/.signature");
	my $builtpkg=$path[-1].'#.*pkg\.tar\.(bz2|gz|lz|xz)$';
	$builtpkg =~ s/\+/\\\+/; # plus sign in filenames interferes with regex search

	opendir (DIR, $port) or return;
	foreach my $f (sort(readdir(DIR))) {
		next if ( $f eq '.' or $f eq '..' );
		$f =~ s/\+/\\\+/;
		if ((grep /$f/, @wanted) >= 1 or
			($f =~ /$builtpkg/)*($options{pkgtoo}==0)) {
			print "... keeping file $port/$f.\n" unless $options{quiet} == 1;
		} else {
			remove ("$port/$f");
		}
	}
	closedir (DIR);
}

sub remove {
	my $path=shift;
	my $append = ($options{dryrun}==1) ? "(dry run)\n" : "\n";
	if (-d $path) {
		print "+ removing directory $path $append";
		rmtree ($path,0,1) if ($options{dryrun}==0);
	} else {
		print "+ removing file $path $append";
		if ($options{dryrun}==0) { unlink "$path" or return; }
	}
}

sub do_sweep {
	# argument either a real directory (not symlink) or has a signature;
	# this subroutine determines which condition was satisfied.
	my $port = shift; my $nf = 0;
	if (! -f "$port/.signature") {
		opendir (PORTDIR,$port) or return;
		foreach my $f (readdir PORTDIR) {
			next if ($f eq '.' or $f eq '..');
			$nf += 1;
		}
		closedir (PORTDIR);
		print "WARN: $port/.signature not found, invalid port directory.";
		rm_emptydir($port,$nf);
	} else {
		sweep($port);
	}
}

sub rm_emptydir {
	my $port = shift; my $nf = shift;
	my $msg = ($options{rmdir}==1) ? "\n":
		"\n  Use -d to remove empty directories.\n";
	my $modal = ($options{dryrun}==0) ? "" : "would be";
	my $post = ($nf == 0) ? "  Empty directory $port $modal deleted.\n" :
		"  Cannot remove $port: directory not empty\n";
	$msg = ($options{rmdir}==1) ? "$msg $post" : $msg ;
	print $msg;
	rmdir ($port) if (($nf == 0) and ($options{dryrun} == 0));
}

sub getportdirs {
	my $collection;
	my @basedirs;
	my $portetc = "/etc/ports/";
	opendir (PORTS_DEFS,$portetc) or die "cannot open $portetc for reading";
	foreach (readdir PORTS_DEFS) {
		next if ($_ eq '.' or $_ eq '..');
		if (/.*(rsync|httpup)$/) {
			open SYNC, $portetc.$_ or die "cannot open $portetc.$_";
			while (<SYNC>) {
				$collection=$2 if /^(destination|ROOT_DIR)=(.+)$/;
			}
			close SYNC;
			push (@basedirs , $collection);
		} elsif (/.*git$/) {
			open SYNC, $portetc.$_ or die "cannot open $portetc.$_";
			while (<SYNC>) {
				$collection="/usr/ports/$1" if /^NAME=(.+)$/;
			}
			close SYNC;
			push (@basedirs , $collection);
		} else {}
	}
	closedir PORTS_DEFS;
	return @basedirs ;
}