#!/usr/bin/env perl

# A hook script to verify what is about to be committed.
# Called by "git commit" with no arguments.  The hook should
# exit with non-zero status after issuing an appropriate message
# if it wants to stop the commit.

use strict;
use File::Temp qw/ :mktemp  /;
use File::Copy;
use Cwd;

$ENV{LC_ALL} = "C";

# attempt to fix whitespace in one file
# $1 - file to fix
# $2 - list of lines containing whitespace errors
sub fix_whitespace($$) {
    my ( $file, $lines ) = @_;

    # usually we have nothing to do ;-)
    return if ( keys( %{$lines} ) == 0 ||
                $file eq "" || $file eq "GNUmakefile" ||
                !( $file =~ /\.(c|cpp|cxx|h|hrc|hxx|idl|inl|java|map|MK|pl|pm|pmk|py|sdi|sh|src|tab)/ ) );

    open( IN, "$file" ) || die "Cannot open $file for reading";
    my ( $out, $tmpfile ) = mkstemp( "/tmp/whitespace-fixing-XXXXXX" );

    my $line_no = 1;
    while ( my $line = <IN> ) {
        if ( $lines->{$line_no} && $line =~ /^(.*[^ \t])[ \t]+$/ ) {
            print $out "$1\n";
        }
        elsif ( $lines->{$line_no} && $line =~ /^[ \t]+$/ ) {
            print $out "\n";
        }
        else {
            print $out $line;
        }
        ++$line_no;
    }
    close( $out );
    close( IN );

    move( $tmpfile, $file ) or die "Cannot move '$tmpfile' to '$file'";

    system( "git add $file" );
    print "Fixed whitespace in '$file'\n";
}

# go through the patch and collect lines to fix
sub check_and_fix_whitespace($)
{
    my ( $head ) = @_;

    my $file = "";
    my %lines = ();
    my $line_no = 0;
    my $line_max = -1;

    my $stash = "";

    # any not staged changes to stash away?
    system( "git update-index -q --refresh" );
    if ( `git diff --name-only --` ) {
        my $fd;
        ( $fd, $stash ) = mkstemp( "/tmp/unstaged-changes-XXXXXX" );
        close( $fd );
        # this will keep the staged changes
        system( "git diff > $stash" );
        system( "git checkout ." );
    }
    open( IN, "git diff-index -p --no-prefix --cached $head -- |" ) || die "Cannot get git diff-index";
    while ( my $line = <IN> ) {
        if ( $line =~ /^\+\+\+ (.*)/ ) {
            fix_whitespace( $file, \%lines );
            $file = $1;
            %lines = ();
            $line_no = 0;
            $line_max = -1;
        }
        elsif ( $line =~ /^@@ -[0-9]+,[0-9]+ \+([0-9]+),([0-9]+) @@/ ) {
            $line_no = $1;
            $line_max = $line_no + $2;
        }
        elsif ( ( $line_no < $line_max ) && ( $line =~ /^[ +]/ ) ) {
            if ( $line =~ /^\+.*[ \t]$/ ) {
                $lines{$line_no} = 1;
            }
            ++$line_no;
        }
    }
    fix_whitespace( $file, \%lines );
    close( IN );
    if ($stash) {
        system( "git apply < $stash" );
        unlink( $stash );
    }
}

# Do the work :-)

# Initial commit: diff against an empty tree object
my $against="4b825dc642cb6eb9a060e54bf8d69288fbee4904";
if ( system( "git rev-parse --verify HEAD >/dev/null 2>&1" ) == 0 ) {
    $against="HEAD"
}

# If you want to allow non-ascii filenames set this variable to true.
my $allownonascii=`git config hooks.allownonascii`;

# Cross platform projects tend to avoid non-ascii filenames; prevent
# them from being added to the repository. We exploit the fact that the
# printable range starts at the space character and ends with tilde.
if ( $allownonascii ne "true" &&
    # Note that the use of brackets around a tr range is ok here, (it's
    # even required, for portability to Solaris 10's /usr/bin/tr), since
    # the square bracket bytes happen to fall in the designated range.
    `git diff --cached --name-only --diff-filter=A -z $against | \
     LC_ALL=C tr -d '[ -~]\\0'` ne "" )
{
    print <<EOM;
Error: Attempt to add a non-ascii file name."

This can cause problems if you want to work"
with people on other platforms."

To be portable it is advisable to rename the file ..."

If you know what you are doing you can disable this"
check using:"

  git config hooks.allownonascii true"

EOM
    exit( 1 );
}

# check for missing doxygen comments in new files
my $doxycheck = "../../bin/find-undocumented-classes";
if (! -e $doxycheck) {
    # bootstrap repo
    $doxycheck =~ s|../../||;
}
open(FILES, "git diff-index --cached --name-only --diff-filter=A $against |") || die "Cannot run git diff-index.";
while (my $file = <FILES>) {
    chomp($file);
    if ($file =~ /\.hxx$/) {
        system("$doxycheck -q $file | sed 's|".getcwd()."/||;'");
    }
}

# be strict about tabs - we don't want them at all, setup your editor
# correctly ;-)
my $err_ext = "";

open( FILES, "git diff-index --cached --name-only $against |" ) || die "Cannot run git diff-index.";
while ( my $file = <FILES> ) {
    chomp( $file );
    if ( $file ne "GNUmakefile" &&
         $file =~ /\.(c|cpp|cxx|h|hrc|hxx|idl|inl|java|map|MK|pmk|pl|pm|sdi|sh|src|tab|xcu|xml)$/) {
        open( F, "git diff-index -p --cached $against -- '$file' |" );
        while ( my $line = <F> ) {
            if ( $line =~ /^\+ *\t/ ) {
                $err_ext .= "$file\n";
                last;
            }
        }
    }
    close( F );
}
close( FILES );

if ( $err_ext ne "" ) {
    print <<EOM;
Error: Your change in the following files introduces tabs in indentation:

$err_ext
Please setup your editor not to use tabs, fix the files, and try again.
We have had enough trouble with tabs in the past :-(

EOM
    exit( 1 );
}

# check for old licenses
my $check_licenses='^+.*\(Sun Industry Standards Source License Version\|GNU Lesser General Public License Version 2.1\)';
my $err_licenses=`git diff-index --cached --name-only $against | while read FILE ; do \
                      if git diff-index -p --cached $against -- "\$FILE" | grep -qs "$check_licenses" ; then \
                          echo "\$FILE" \
                      fi \
                  done`;
chomp( $err_licenses );
if ( $err_licenses ne "" && $err_licenses ne "git-hooks/pre-commit" ) {
    print <<EOM;
Error: Your change in the following files introduces old licenses:

$err_licenses

Please check with the author(s) that they agree with upgrading the
license to LGPL3, and change the license accondingly.

EOM
    exit( 1 );
}

# fix whitespace in code
check_and_fix_whitespace( $against );

# check the rest of the files
my $filter_patches=`git diff-index --check --cached $against -- | sed '/\.\(diff\|patch\):/,/.*/d'`;
chomp( $filter_patches );
if ( $filter_patches ne "" ) {
    print "WARNING:\n\n$filter_patches\n";
}

# all OK
exit( 0 );
# vi:set shiftwidth=4 expandtab: