#!/usr/bin/perl -w
use strict;

if ($#ARGV != 1) {
	print "Usage: $0 suse_machine git_range\n";
	exit 1;
}

my $machine = $ARGV[0];
my $range = $ARGV[1];
my $idsfile = "/dev/shm/ids";
my $patchfile = "/dev/shm/patch";
my $user = 'Jiri Slaby <jslaby@suse.cz>';
my $new_version = "";

if ($range =~ /^v(2\.6\.[0-9]+(\.[0-9]+)?)\.\.v(2\.6\.[0-9]+\.([0-9]+))$/ ||
    $range =~ /^v(3\.[0-9]+(\.[0-9]+)?)\.\.v(3\.[0-9]+\.([0-9]+))$/) {
	$new_version = $3;
	$patchfile .= "-";
	if (defined $2) {
		$patchfile .= "$1-$4";
	} else {
		$patchfile .= $3;
	}
}

open GIT, "git log --format=%B $range|" ||
	die "git log cannot be run";
open OUT, "|ssh -C $machine -o StrictHostKeyChecking=no 'cat >$idsfile'" ||
	die "ssh didn't start";

my @SHAs;
my $cont = 0;

while (<GIT>) {
	if ($cont) {
		if (/^\s+([0-9a-f]{40})\s*[\])]$/) {
			print OUT "$1\n";
			push @SHAs, $1;
			$cont = 0;
			next;
		}
	}
	if (/^commit ([0-9a-f]{40}) upstream\.?$/ ||
		/^[\[(]\s*[Uu]pstream commit ([0-9a-f]{40})\s*[\])]$/ ||
		/^[uU]pstream commit ([0-9a-f]{40})\.$/ ||
		/^This is a backport of ([0-9a-f]{40})$/ ||
		/^\(cherry picked from commit ([0-9a-f]{40})\)$/) {
		print OUT "$1\n";
		push @SHAs, $1;
	} elsif (/^[\[(]\s*[Uu]pstream commits ([0-9a-f]{40})\s+and\s*$/) {
		print OUT "$1\n";
		push @SHAs, $1;
		$cont = 1;
	} elsif (/\b[0-9a-f]{40}\b/) {
		print "\tUnmatched SHA: $_";
	}
}

close OUT;
close GIT;

print "Written $idsfile on $machine\n";

open GIT, "git diff $range|" ||
	die "git diff cannot be run";
open OUT, "|ssh -C $machine 'cat >$patchfile'" ||
	die "ssh didn't start";

print OUT "From: $user\n";
print OUT "Subject: Linux $new_version\n";
print OUT "Patch-mainline: $new_version\n";
foreach (@SHAs) {
	print OUT "Git-commit: $_\n";
}

print OUT "\n";
print OUT "Signed-off-by: $user\n";
print OUT "---\n";

while (<GIT>) {
	print OUT;
}

close OUT;
close GIT;

print "Written $patchfile on $machine\n";

0;