#!/usr/athena/bin/perl

use File::Spec::Functions qw(:ALL);
use File::Copy;
use File::Path;
use Data::Dumper;
use Getopt::Long;
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";
(-d $outdir || mkdir($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 $outfiledir = catdir($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', $updatename, $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."

echo "[$PWD] begin dry run"

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 -p1 <"$patchdir/update.diff" || due "error: Patch dry run failed."

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

mv .scripts-version .scripts-version.old
patch -stN --no-backup-if-mismatch -p1 <"$patchdir/update.diff" || :
xargs rm -f <"$patchdir/files.delete"
cp -a "$patchdir/newfiles/." .
(cat .scripts-version.old; date; echo "%s"; echo "%s") >>.scripts-version
rm -f .scripts-version.old

rm -f .scripts-security-upd-lock

echo "[$PWD] done"

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