#!/usr/bin/env perl

use File::Spec::Functions qw(:ALL);
use File::Copy;
use File::Path;
use Data::Dumper;
use Getopt::Long;
use Archive::Tar;
use Cwd;
use strict;
use warnings;

my $scriptsdev = "";

GetOptions(
#"redo-delete" => \$redodelete,
#	   "redo-add" => \$redoadd,
#	   "redo-replace" => \$redoreplace,
#	   "redo-diff" => \$redodiff,
#	   "redo-all" => sub {$redodelete = $redoadd = $redoreplace = $redodiff = 1;},
	   "dev" => sub {$scriptsdev = "dev";},
		  );

if (@ARGV < 3) {
  print STDERR "Usage: $0 package oldversion newversion\n";
  exit(1);
}

my ($package, $oldversion, $newversion) = @ARGV;
my ($old, $new, $updatename) = ($package.'-'.$oldversion, $package.'-'.$newversion, $package.'-'.$oldversion.'-to-'.$newversion);

my $proposaldir = $updatename.".proposal";
my $outdir = catdir("/mit/scripts/deploy$scriptsdev/updates/", $updatename);

(-d $proposaldir) or die "Can't find $proposaldir, did you run propose-update?\n";
((! -e $outdir) && mkdir($outdir)) or die "mkdir($outdir) failed: $!";

my $olddir = catdir($proposaldir,$old);
my $newdir = catdir($proposaldir,$new);
(-d $olddir && -d $newdir) or die "Packages not unpacked?\n";

sub readFileList($) {
  my ($list) = @_;
  open(LIST, $list) or die "Can't read $list: $!\n";
  my @files = map { chomp; s|$newdir\/?||g; [split(' ', $_, 2)] } <LIST>;
  close(LIST);
  return @files;
}

my @todelete = readFileList(catfile($proposaldir, "files.delete"));
my @toadd = readFileList(catfile($proposaldir, "files.add"));
my @toreplace = readFileList(catfile($proposaldir, "files.replace"));

open(CHECKMD5, ">", catfile($outdir, "check.md5")) or die "Can't open check.md5: $!";
print CHECKMD5 map { join("  ", @{$_})."\n" } @todelete, @toreplace;
close(CHECKMD5);

open(ABSENT, ">", catfile($outdir, "oldfiles.absent")) or die "Can't open oldfiles.absent: $!";
print ABSENT map { $_->[1]."\n" } @toadd;
close(ABSENT);

open(DELETE, ">", catfile($outdir, "files.delete")) or die "Can't open files.delete: $!";
print DELETE map { $_->[1]."\n" } @todelete, @toreplace;
close(DELETE);

my $outfiletarball = catfile($outdir, "newfiles.tar.gz");
my $cwd = getcwd();

chdir($newdir);
my $tar = Archive::Tar->new;
$tar->add_files(map { $_->[1] } @toadd, @toreplace);
$tar->write($outfiletarball, 1);
chdir($cwd) or die "Couldn't chdir back to $cwd: $!\n";

if (0) {
    my $outfiledir = catdir($outdir, "newfiles");
    (-d $outfiledir || mkdir($outfiledir)) or die "Can't mkdir($outfiledir)\n";
    
    foreach my $file (@toadd, @toreplace) {
	my $filename = $file->[1];
	my $src = catfile($newdir, $filename);
	my $dest = catfile($outfiledir, $filename);
	my (undef, $dir, undef) = splitpath($dest);
	mkpath($dir);
	copy($src, $dest) or die "Couldn't copy $filename from $src to $dest: $!";
    }
}

copy(catfile($proposaldir, "update.diff"), catfile($outdir, "update.diff")) or die "Couldn't copy update.diff: $!";

open (SCRIPT, ">", catfile($outdir, "update")) or die "Couldn't write update: $!";
printf SCRIPT <<'EOF', catfile("/mit/scripts/deploy/", $old), catfile("/mit/scripts/deploy/", $new);
#!/bin/bash
set -e -o noclobber

die () { echo "$1" >&2; exit 1; }

patchdir=$(dirname "$0")

>.scripts-security-upd-lock || die "error: Unable to obtain update lock."

packages=$(tail -n 1 .scripts-version)

echo "[$PWD] begin dry run"

found=""
newpackages=""
for package in $packages; do
    if [ "$package" = "%s" ]; then
    found="yes"
    newpackages="$newpackages%s "
    else
    newpackages="$newpackages$package "
    fi
done

[ "$found" = "yes" ] || die "error: Correct version not found."
xargs -n1 test ! -e <"$patchdir/oldfiles.absent" || die "error: Conflicting files exist."
md5sum -c "$patchdir/check.md5" || die "error: MD5 check failed."
patch -stN --dry-run --no-backup-if-mismatch -p2 <"$patchdir/update.diff" || die "error: Patch dry run failed."

echo "[$PWD] dry run OK, applying update"

mv .scripts-version .scripts-version.old
patch -stN --no-backup-if-mismatch -p2 <"$patchdir/update.diff" || :
xargs rm -f <"$patchdir/files.delete"
tar -xzf "$patchdir/newfiles.tar.gz"
(cat .scripts-version.old; date "+%%F %%T %%z"; echo "$USER@$(hostname)"; echo "$patchdir"; echo "$newpackages") >>.scripts-version
rm -f .scripts-version.old

rm -f .scripts-security-upd-lock

echo "[$PWD] done"

exit 0
EOF
chmod 0755, catfile($outdir, "update");