<perl>
use Encode;

    # common functions for all recent_list_*.wml
    
sub get_recent_list {
    my ($time, $number, $rel_path, $english_dir, $files_match, $data_callback, $format_list_callback, $format_item_callback) =@_;

    #warn "get_recent_list($time, $number, $rel_path, $english_dir, $files_match, $data_callback, $format_list_callback, $format_item_callback)\n";
    my $since_date = determine_since_date($time);
    #warn "since_date=$since_date\n";
    my $files = get_matching_filenames_by_time($rel_path, $english_dir, $files_match, $since_date);
    my $data = get_files_data($files, $english_dir, $data_callback);
    my $filtered_data = filter_items($data, $since_date, $number);

    my $str = $format_list_callback->($filtered_data, $format_item_callback);

    return $str;
}

    
sub slurp_file_openrecode {
    my ($file, $eng_dir) = @_;

    (my $trans_title = $file) =~ s/\.wml$/\.title/;
    # read file in
    my $fh = openrecode($file, $trans_title, "$eng_dir/$file")
	or die "couldn't open $eng_dir/$file: $!\n";
    my $content;
    <protect pass=2>
    {
	local $/;
	$content = <$fh>;
    }
    </protect>
	close $fh;

    return $content;
}
sub slurp_file {
    my ($file) = @_;

    open my $fh, '<', $file
	or die "couldn't open $file: $!\n";
    my $content;
    <protect pass=2>
    {
	local $/;
	$content = <$fh>;
    }
    </protect>
    close $fh;

    return $content;
}

sub match_tag {
    my ($content, $tag) = @_;

    my $value;
    $content = Encode::decode_utf8($content);
    <protect pass=2>
    if ($content =~ m|^<define-tag $tag>\s*(.*?)\s*</define-tag>|ms) {
	$value = Encode::encode_utf8(qq/$1/); }      # all
    </protect>
    return $value;
}

sub match_tag_first_p {
    my ($content, $tag) = @_;

    my $value;
    <protect pass=2>
    if ($content =~ m"^<define-tag $tag>\s*(?:(.*?</p>)|(.*?)</define-tag>)"ms) {
	$value = qq/$1/; }      # all
    </protect>
    return $value;
}

sub determine_since_date {
    my ($time) = @_;

    return parse_time($time) if $time;
    return '';
}
	
sub determine_relevant_years {
    my ($since_date) = @_;
	
    my $year = $(CUR_YEAR);
    $since_year = $year;
    if ($since_date){
	$since_year = (gmtime($since_date))[5] + 1900;
	if ($since_year > $year) {
	    warn "since_year > year ($since_year > $year)\n";
	}
    }
    # djpig: take $since_year-1, perhaps better define an $oldest_year?
    # djpig: but there should be no more updates to an item after a year
    # djpig: we're saving time so.
    return [($since_year-1) .. $year];
}
    
sub get_matching_filenames_by_time {
    my ($rel_path, $english_dir, $match, $since_date) =@_;

    my @files;

    my $years = determine_relevant_years($since_date);
    for my $act_year (@$years) {
	my $act_path = $rel_path eq '.' ? $act_year : "$rel_path/$act_year"; 
	my $new_files = get_matching_filenames($act_path, "$english_dir/$act_year", $match);

	push @files, @$new_files;
    }

    return \@files;
}
    
sub get_matching_filenames {
    my ($rel_path, $eng_dir, $match) = @_;

    #warn "get_match_filesnames( $rel_path, $eng_dir, $match )\n";
    opendir my $dir_h, $eng_dir
	or die "couldn't open dir $eng_dir: $!\n";
    my @files = grep { ($_ =~ $match)
			   && -f "$eng_dir/$_"
			   && ($_="$rel_path/$_")
    } readdir($dir_h);
    closedir $dir_h;

    return \@files;
}

sub get_files_data {
    my ($files, $eng_dir, $callback) = @_;

    my %data;
    foreach my $file (@$files) {
	$callback->($file, $eng_dir, \%data);
    }

    return \%data;
}

sub filter_items {
    my ($data, $since_date, $minnumber) = @_;

    my @dates = sort { $b <=> $a } keys %$data;
    #warn "since_date: ".scalar gmtime($since_date)." minnum: $minnumber\n";
    my $count = 0;
    my %filtered_data;
    foreach my $date (@dates) {
	#warn "date: ".scalar gmtime($date)." ($count >= $minnumber) && ($date < $since_date)\n";
	if ($count >= $minnumber) {
	    if((!$since_date && $minnumber)
	       || (($since_date || !$minnum)
		   && ($date lt $since_date)) ) {
		last;
	    }
	}
	$filtered_data{$date} = $data->{$date};
	$count += scalar @{$data->{$date}};
    }

    return \%filtered_data;
}

# parse_time gets as argument a string and returns a unix timestamp
# Input: $time_str - String with the following format
#                    $time_str ::= <integer>(d|w|m|y)
# Output: integer timestamp
#
# parse_time subtracts <integer> days/weeks/months from the actual time and
# returns the corresponding timestamp. Years are handled special: 1y means
# "since January, 1st of actual year", 2y means "since January, 1st of
# last year", etc.
sub parse_time {
    my $time_str = shift;
    my $year = (gmtime())[5] + 1900;
    my $time = time();
    my $res;

    for ($time_str) {
	/\d{4}/ && do {
	    $res = timegm(0,0,0,1,0,$year);
	    last;
	};

	/(\d+)d/ && do {
	    $res = $time - 86400 * $1;
	    last;
	};

	/(\d+)w/ && do {
	    $res = $time - 86400 * 7 * $1;
	    last;
	};

	/(\d+)m/ && do {
	    # All months have 30 days,
	    # all other would be far more complicated
	    $res = $time - 86400 * 30 * $1;
	    last;
	};

	/(\d+)y/ && do {
	    # years are handled special
	    my $ryear = $year - $1 + 1; # the actual year count as a whole one
	    $res = timegm(0,0,0,1,0,$ryear); # 01.01.$ryear 00:00:00
	    last;
	};

    }

    return $res;
}

# iso2stamp converts a date in ISO format (YYYY-MM-DD) to an
# unix timestamp for 23:59:59 on the specified day
# Input: $time - String with the ISO date
# Output: integer timestamp
sub iso2stamp {
    my $time = shift;

    if ($time =~ /undated/) {
	return 0;
    }
    my ($year, $month, $day) = ($time =~ /(\d{4})-(\d{1,2})-(\d{1,2})/);
    unless ($year && $month && $day) { warn "not an ISO date: $time\n"; }

    return timegm( 59, 59, 23, $day, $month-1, $year);
}

</perl>