todo.pl

#!/usr/bin/perl
# added an undo feature <Fri May 11 17:38:57 CDT 2012>
use feature qw/switch/;
use File::Basename;
use File::Copy;

my $todo = "$ENV{HOME}/TODO";
my $todo_dir = "$ENV{HOME}/.tood";
my $todo_tmp = "/tmp/tood_TODO";
my @todo_backups = sort {
    ($b =~ /\.(\d+)$/)[0] <=> ($a =~ /\.(\d+)$/)[0]
        ||
        uc($a) cmp uc($b)
} glob "$todo_dir/TODO.{[0-9],[0-9][0-9]}";
my $todo_nbackups = 10;
sub usage
{
    print "Usage: ", basename($0) , " <subcommand> [<arguments>]\n";
    print "Subcommands\n";
    print "\tshow\n";
    print "\tadd <new_task>\n";
    print "\tins <position> <new_task>\n";
    print "\tmv <position> <new_position>\n";
    print "\trep <position> <new_task>\n";
    print "\ttail <position> <tail text>\n";
    print "\trm <position>\n";
    print "\tundo\n";
}

sub show
{
    if (! -z $todo)
    {
        open(TODO, '<', $todo);
        $line = 1;

        while(<TODO>)
        {
            if ($line < 10)
            {
                print " ";
            }
            print "[$line] $_";
            $line++;
        }
    }
    else {
        print "Nothing to do!\n";
    }
}

sub add
{
    open(TODO, '>>', $todo);
    if (@_ > 0) { print TODO join (" ", @_) . "\n";}
    else
    {
        while (<STDIN>)
        {
            print TODO;
        }
    }
    close(TODO);
}

sub insert
{
    my $pos = 0;
    my @new_tasks = ();
    if (@_ and $_[0] =~ /[0-9]+/)
    {
        ($pos, @new_tasks) = @_;
    }
    else
    {
        $pos = 1;
        @new_tasks = @_;
    }
    open(TODO, '<', $todo);
    @items = <TODO>;
    close(TODO);
    if ($pos > @items)
    {
        add(@new_tasks);
        return;
    }
    #$pos > 0 or $pos = 1;
    open(TODO, '>', $todo);
    $line_num = 1;
    foreach $item (@items)
    {
        if ($line_num == $pos)
        {
            add(@new_tasks);
            open(TODO, '>>', $todo);
        }
        print TODO $item;
        $line_num++;
    }
    close(TODO);
}

sub remove
{
    my @completed_tasks = @_;
    open(TODO, '<', $todo);
    @items = <TODO>;
    close(TODO);
    open(TODO, '>', $todo);
    $line_num = 1;
    foreach $item (@items)
    {
        $print_item = 1;
        foreach (@completed_tasks)
        {
            if ($line_num == $_)
            {
               $print_item = 0;
               $removed = $item;
               last;
            }
        }
        if ($print_item)
        {
            print TODO $item;
        }
        $line_num++;
    }
    close(TODO);
    $removed;
}

sub make_tmp_TODO
{
    copy($todo, $todo_tmp);
}

sub unbackup_TODO
{
        copy("$todo_dir/TODO.0", $todo);
        for (reverse @todo_backups)
        {
            m/\.([0-9]+)$/;
            my $new_number = $1;
            $new_number = ($new_number - 1);
            ($new_number >= 0) and
                copy($_, "$todo_dir/TODO." . $new_number);
        }
}

sub back_up_TODO
{
    # rename the old ones
    system("diff", $todo, $todo_tmp);
    $return  = $?;
    if ($return)
    {
        for (@todo_backups)
        {
            m/\.([0-9]+)$/;
            my $new_number = $1;
            $new_number = ($new_number + 1);
            ($new_number < $todo_nbackups) and
                copy($_, "$todo_dir/TODO." . $new_number);
        }
        copy($todo_tmp, "$todo_dir/TODO.0");
    }
}
given (shift @ARGV)
{
    # save the current TODO file as .tood/TODO.#
    # where # is the count of other such files +1
    make_tmp_TODO();
    when (/show|ls|list/)
    {
        show;
    }
    when ("add")
    {
        add(@ARGV);
    }
    when ("ins")
    {
        insert(@ARGV);
    }
    when ("rm")
    {
        remove(@ARGV);
    }
    when ("mv")
    {
        # TODO: allow multiple items to move
        chomp($task = remove(shift));
        insert(shift, $task);
    }
    when ("tail")
    {
        chomp($task = remove($ARGV[0]));
        insert(shift, $task . shift);
    }
    when ("rep")
    {
        remove($ARGV[0]);
        insert(@ARGV);
    }
    when ("undo")
    {
        unbackup_TODO();
    }
    default
    {
        usage;
    }
    # if the real TODO does not differ from
    # the recently made backup, then just delete it
}
back_up_TODO();

# vim:set ft=perl