##############################################################################
# Copyright (c) 2013, Lawrence Livermore National Security, LLC.
# Produced at the Lawrence Livermore National Laboratory.
#
# This file is part of Spack.
# Written by Todd Gamblin, tgamblin@llnl.gov, All rights reserved.
# LLNL-CODE-647188
#
# For details, see https://scalability-llnl.github.io/spack
# Please also see the LICENSE file for our notice and the LGPL.
#
# This program 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 2.1 dated February 1999.
#
# This program is distributed in the hope that it will be useful, but
# WITHOUT ANY WARRANTY; without even the IMPLIED WARRANTY OF
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the terms and
# conditions of the GNU General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public License
# along with this program; if not, write to the Free Software Foundation,
# Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
##############################################################################
import os

from external import argparse
import llnl.util.tty as tty
from llnl.util.tty.colify import colify

import spack
from spack.util.executable import *

description = "Query packages associated with particular git revisions in spack."

def setup_parser(subparser):
    sp = subparser.add_subparsers(
        metavar='SUBCOMMAND', dest='pkg_command')

    list_parser = sp.add_parser('list', help=pkg_list.__doc__)
    list_parser.add_argument('rev', default='HEAD', nargs='?',
                             help="Revision to list packages for.")

    diff_parser = sp.add_parser('diff', help=pkg_diff.__doc__)
    diff_parser.add_argument('rev1', nargs='?', default='HEAD^',
                             help="Revision to compare against.")
    diff_parser.add_argument('rev2', nargs='?', default='HEAD',
                             help="Revision to compare to rev1 (default is HEAD).")

    add_parser = sp.add_parser('added', help=pkg_added.__doc__)
    add_parser.add_argument('rev1', nargs='?', default='HEAD^',
                             help="Revision to compare against.")
    add_parser.add_argument('rev2', nargs='?', default='HEAD',
                            help="Revision to compare to rev1 (default is HEAD).")

    rm_parser = sp.add_parser('removed', help=pkg_removed.__doc__)
    rm_parser.add_argument('rev1', nargs='?', default='HEAD^',
                           help="Revision to compare against.")
    rm_parser.add_argument('rev2', nargs='?', default='HEAD',
                           help="Revision to compare to rev1 (default is HEAD).")


def get_git():
    # cd to spack prefix to do git operations
    os.chdir(spack.prefix)

    # If this is a non-git version of spack, give up.
    if not os.path.isdir('.git'):
        tty.die("No git repo in %s. Can't use 'spack pkg'" % spack.prefix)

    return which("git", required=True)


def list_packages(rev):
    git = get_git()
    relpath = spack.packages_path[len(spack.prefix + os.path.sep):] + os.path.sep
    output = git('ls-tree', '--full-tree', '--name-only', rev, relpath,
                 return_output=True)
    return sorted(line[len(relpath):] for line in output.split('\n') if line)


def pkg_list(args):
    """List packages associated with a particular spack git revision."""
    colify(list_packages(args.rev))


def diff_packages(rev1, rev2):
    p1 = set(list_packages(rev1))
    p2 = set(list_packages(rev2))
    return p1.difference(p2), p2.difference(p1)


def pkg_diff(args):
    """Compare packages available in two different git revisions."""
    u1, u2 = diff_packages(args.rev1, args.rev2)

    if u1:
        print "%s:" % args.rev1
        colify(sorted(u1), indent=4)
        if u1: print

    if u2:
        print "%s:" % args.rev2
        colify(sorted(u2), indent=4)


def pkg_removed(args):
    """Show packages removed since a commit."""
    u1, u2 = diff_packages(args.rev1, args.rev2)
    if u1: colify(sorted(u1))


def pkg_added(args):
    """Show packages added since a commit."""
    u1, u2 = diff_packages(args.rev1, args.rev2)
    if u2: colify(sorted(u2))


def pkg(parser, args):
    action = { 'diff'    : pkg_diff,
               'list'    : pkg_list,
               'removed' : pkg_removed,
               'added'   : pkg_added }
    action[args.pkg_command](args)

Add command to show packages added in particular git revisions.