#!/bin/sh

: <<=cut
=pod

=head1 NAME

marks - a tool for marking and acting on file paths

=head1 SYNOPSIS

    marks add <path>     # Add a file path to the mark list
    marks + <path>       # Shorthand for add
    marks remove <path>  # Remove a file path from the mark list
    marks - <path>       # Shorthand for remove
    marks clear          # Remove all marks from list
    marks ls             # List current marks
    marks cp             # Copy marked files to current directory
    marks mv             # Move files to current directory and unmark
    marks each <command> # Execute command with each marked file as parameter
    marks -h             # Print help message

=head1 DESCRIPTION

marks stores a list of marked file paths in an SQLite database called marks.db
in the user's home directory.  Once marked, files can be copied, moved, listed,
or passed as parameters to arbitrary shell commands.

Commands are intended to be invoked as subcommands of mark(1), in the style of
git(1).

=head1 COMMANDS

=head2 marks-add, marks +

Add one or more paths to the mark list.  Relative paths will be stored by their
absolute location.  Repeated commands are idempotent - a path can only appear
once in the mark list.

C<marks +> is a convenience shorthand for C<marks add>.

=head2 mark-remove

Remove one or more paths from the mark list.  Relative paths will be resolved
to their absolute location before the list is searched.

=head2 marks-clear

Clear the entire mark list.

=head2 marks-ls

List all currently marked paths, one line per path.

=head2 marks-ls --print0

List all currently marked paths, separated by null characters, for use when
piping to C<xargs -0> or other commands which expect null-terminated file
lists.  Analogous to C<find -print0>.  This is useful where filenames contain
whitespace, quotes, etc.

=head2 marks-cp

Copy all marked paths to the current working directory.

=head2 marks-mv

Move all marked paths to the current working directory, and remove them from
the mark list.

=head2 marks-each

Execute the provided command once per marked path, with the path as a
parameter, and print any output from the command.

This is crudely analogous to C<xargs>.  While good enough for simple commands,
it's likely to break in more complex cases, and may be slow for large mark
lists.  Consider using marks-ls --print0 and xargs(1) instead.

=head1 SEE ALSO

App::MarkFiles

=head1 LICENSE

    marks is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation, version 2 of the License.

=head1 AUTHOR

Brennen Bearnes

=cut

print_help() {
  echo "$0 - mark and operate on files"
  echo
  echo "Usage: marks [command] [args]"
  echo "    marks               - List current marks (shortcut for mark ls)"
  echo "    marks add [path]    - Add a file path to the mark list"
  echo "    marks + [path]      - Shorthand for add"
  echo "    marks remove [path] - Remove a file path from the mark list"
  echo "    marks - [path]      - Shorthand for remove"
  echo "    marks clear         - Clear mark list"
  echo "    marks cp            - Copy marked files to current directory"
  echo "    marks each [cmd]    - Execute command for each marked file"
  echo "    marks ls            - List current marks"
  echo "    marks mv            - Move files to current directory and unmark"
  echo "    marks -h            - Print this help message"
}

if [ $# -lt 1 ]; then
  # No arguments - let's just list the existing marks:
  exec mark-ls
elif [ "$1" = "--help" ] || [ "$1" = "-h" ]; then
  print_help
  exit 0
elif [ "$1" = '+' ]; then
  subprog="marks-add"
elif [ "$1" = '-' ]; then
  subprog="marks-remove"
else
  subprog="marks-$1"
fi

# Make sure that the subcommand we're trying to run exists:
command -v "$subprog" >/dev/null 2>&1 || {
  echo "marks: '$1' is not a marks command."
  echo
  print_help
  exit 1
}

# Get rid of subcommand name from arguments:
shift
exec "$subprog" "$@"