#!/usr/bin/python
#
# Check components of build dependencies and warn about universe/multiverse
# ones, for a package destined for main/restricted
#
# Copyright (C) 2011 Canonical
#
# Authors:
#  Martin Pitt
#
# 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 3.
#
# 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 GNU General Public License for more
# details.
#
# You should have received a copy of the GNU General Public License along with
# this program; if not, write to the Free Software Foundation, Inc.,
# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

import apt, sys, os.path

apt_cache = apt.Cache()

def check_support(pkgname, alt=False):
    '''Check if pkgname is in main or restricted.

    This prints messages if a package is not in main/restricted, or only
    partially (i.  e. source in main, but binary in universe).
    '''
    if alt:
        prefix = '  ... alternative ' + pkgname
    else:
        prefix = ' * ' + pkgname

    try:
        pkg = apt_cache[pkgname]
    except KeyError:
        print >> sys.stderr, pkgname, 'does not exist (pure virtual?)'
        return False
    
    section = pkg.candidate.section
    if section.startswith('universe') or section.startswith('multiverse'):
        # check if the source package is in main and thus will only need binary
        # promotion
        sr = apt.apt_pkg.SourceRecords()
        if not sr.lookup(pkg.candidate.source_name):
            print >> sys.stderr, 'ERROR: Cannot lookup source package for', pkg.name
            print prefix, 'package is in', section.split('/')[0]
            return False
        src = apt.apt_pkg.TagSection(sr.record)
        if src['Section'].startswith('universe') or src['Section'].startswith('multiverse'):
            print prefix, 'binary and source package is in', section.split('/')[0]
            return False
        else:
            print prefix, 'is in', section.split('/')[0] + ', but its source', pkg.candidate.source_name, 'is already in main; file an ubuntu-archive bug for promoting the current preferred alternative'
            return True

    if alt:
        print prefix, 'is already in main; consider preferring it'

    return True


#
# main
#

if not os.path.exists('debian/control'):
    print >> sys.stderr, 'debian/control not found. You need to run this tool in a source package directory'
    sys.exit(1)

print 'Checking support status of build dependencies...'

# get build dependencies from debian/control
control=apt.apt_pkg.TagFile(open('debian/control'))
control.next()


any_unsupported = False

for field in ('Build-Depends', 'Build-Depends-Indep'):
    if field not in control.section:
        continue
    for or_group in apt.apt_pkg.parse_src_depends(control.section[field]):
        pkgname = or_group[0][0]
        if not check_support(pkgname):
            # check non-preferred alternatives
            for altpkg in or_group[1:]:
                if check_support(altpkg[0], alt=True):
                    break
            else:
                any_unsupported = True

if any_unsupported:
    print '\nPlease check https://wiki.ubuntu.com/MainInclusionProcess if this source package needs to get into in main/restricted, or reconsider if the package really needs above dependencies.'
else:
    print 'All build dependencies are supported in main or restricted.'