#!/usr/bin/python -tt

# 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; either version 2 of the License, or
# (at your option) any later version.
#
# 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.
# copyright 2006 Duke University
# author seth vidal

# sync all or the newest packages from a repo to the local path
# TODO:
#     have it print out list of changes
#     make it work with mirrorlists (silly, really)
#     man page/more useful docs
#     deal nicely with a package changing but not changing names (ie: replacement)

# criteria
# if a package is not the same and smaller then reget it
# if a package is not the same and larger, delete it and get it again
# always replace metadata files if they're not the same.





import os
import sys
import shutil
import stat

from optparse import OptionParser
from urlparse import urljoin

import yum
import yum.Errors
from yum.misc import getCacheDir
from yum.constants import *
from yum.packageSack import ListPackageSack
import rpmUtils.arch
import logging
from urlgrabber.progress import TextMeter, TextMultiFileMeter
import urlgrabber

# for yum 2.4.X compat
def sortPkgObj(pkg1 ,pkg2):
    """sorts a list of yum package objects by name"""
    if pkg1.name > pkg2.name:
        return 1
    elif pkg1.name == pkg2.name:
        return 0
    else:
        return -1
        
class RepoSync(yum.YumBase):
    def __init__(self, opts):
        yum.YumBase.__init__(self)
        self.logger = logging.getLogger('yum.verbose.reposync')
        self.opts = opts

def localpkgs(directory):
    names = os.listdir(directory)

    cache = {}
    for name in names:
        fn = os.path.join(directory, name)
        try:
            st = os.lstat(fn)
        except os.error:
            continue
        if stat.S_ISDIR(st.st_mode):
            subcache = localpkgs(fn)
            for pkg in subcache.keys():
                cache[pkg] = subcache[pkg]
        elif stat.S_ISREG(st.st_mode) and name.endswith(".rpm"):
            cache[name] = { 'path': fn, 'size': st.st_size, 'device': st.st_dev }
    return cache

def is_subpath(path, root):
    root = os.path.realpath(root)
    path = os.path.realpath(os.path.join(root, path))
    # join() is used below to ensure root ends with a slash
    return path.startswith(os.path.join(root, ''))

def parseArgs():
    usage = """
    Reposync is used to synchronize a remote yum repository to a local 
    directory using yum to retrieve the packages.
    
    %s [options]
    """ % sys.argv[0]

    parser = OptionParser(usage=usage)
    parser.add_option("-c", "--config", default='/etc/yum.conf',
        help='config file to use (defaults to /etc/yum.conf)')
    parser.add_option("-a", "--arch", default=None,
        help='act as if running the specified arch (default: current arch, note: does not override $releasever. x86_64 is a superset for i*86.)')
    parser.add_option("--source", default=False, dest="source", action="store_true",
                      help='operate on source packages')
    parser.add_option("-r", "--repoid", default=[], action='append',
        help="specify repo ids to query, can be specified multiple times (default is all enabled)")
    parser.add_option("-e", "--cachedir",
        help="directory in which to store metadata")
    parser.add_option("-t", "--tempcache", default=False, action="store_true", 
        help="Use a temp dir for storing/accessing yum-cache")
    parser.add_option("-d", "--delete", default=False, action="store_true",
        help="delete local packages no longer present in repository")
    parser.add_option("-p", "--download_path", dest='destdir', 
        default=os.getcwd(), help="Path to download packages to: defaults to current dir")
    parser.add_option("--norepopath", dest='norepopath', default=False, action="store_true",
        help="Don't add the reponame to the download path. Can only be used when syncing a single repository (default is to add the reponame)")
    parser.add_option("-g", "--gpgcheck", default=False, action="store_true",
        help="Remove packages that fail GPG signature checking after downloading")
    parser.add_option("-u", "--urls", default=False, action="store_true", 
        help="Just list urls of what would be downloaded, don't download")
    parser.add_option("-n", "--newest-only", dest='newest', default=False, action="store_true", 
        help="Download only newest packages per-repo")
    parser.add_option("-q", "--quiet", default=False, action="store_true", 
        help="Output as little as possible")
    parser.add_option("-l", "--plugins", default=False, action="store_true", 
        help="enable yum plugin support")
    parser.add_option("-m", "--downloadcomps", default=False, action="store_true",
        help="also download comps.xml")
    parser.add_option("","--download-metadata", dest="downloadmd", 
        default=False, action="store_true", 
        help="download all the non-default metadata")
    parser.add_option("", "--allow-path-traversal", default=False,
        action="store_true",
        help="Allow packages stored outside their repo directory to be synced "
             "(UNSAFE, USE WITH CAUTION!)")
    (opts, args) = parser.parse_args()
    return (opts, args)


def main():
    (opts, junk) = parseArgs()
    
    if not os.path.exists(opts.destdir) and not opts.urls:
        try:
            os.makedirs(opts.destdir)
        except OSError, e:
            print >> sys.stderr, "Error: Cannot create destination dir %s" % opts.destdir
            sys.exit(1)
    
    if not os.access(opts.destdir, os.W_OK) and not opts.urls:
        print >> sys.stderr, "Error: Cannot write to  destination dir %s" % opts.destdir
        sys.exit(1)
        
    my = RepoSync(opts=opts)
    my.doConfigSetup(fn=opts.config, init_plugins=opts.plugins)

    # Force unprivileged users to have a private temporary cachedir
    # if they've not given an explicit cachedir
    if os.getuid() != 0 and not opts.cachedir:
        opts.tempcache = True

    if opts.tempcache:
        if not my.setCacheDir(force=True):
            print >> sys.stderr, "Error: Could not make cachedir, exiting"
            sys.exit(50)
        my.conf.uid = 1 # force locking of user cache
    elif opts.cachedir:
        my.repos.setCacheDir(opts.cachedir)

    # Lock if they've not given an explicit cachedir
    if not opts.cachedir:
        try:
            my.doLock()
        except yum.Errors.LockError, e:
            print >> sys.stderr, "Error: %s" % e
            sys.exit(50)

    #  Use progress bar display when downloading repo metadata
    # and package files ... needs to be setup before .repos (ie. RHN/etc.).
    if not opts.quiet:
        my.repos.setProgressBar(TextMeter(fo=sys.stdout), TextMultiFileMeter(fo=sys.stdout))
    try:
        my.doRepoSetup()
    except yum.Errors.RepoError, e:
        print >> sys.stderr, "Error setting up repositories: %s" % e
        sys.exit(1)

    if len(opts.repoid) > 0:
        myrepos = []
        
        # find the ones we want
        for glob in opts.repoid:
            add_repos = my.repos.findRepos(glob)
            if not add_repos:
                print >> sys.stderr, "Warning: cannot find repository %s" % glob
                continue
            myrepos.extend(add_repos)

        if not myrepos:
            print >> sys.stderr, "No repositories found"
            sys.exit(1)
        
        # disable them all
        for repo in my.repos.repos.values():
            repo.disable()
        
        # enable the ones we like
        for repo in myrepos:
            repo.enable()

    # --norepopath can only be sensibly used with a single repository:
    if len(my.repos.listEnabled()) > 1 and opts.norepopath:
        print >> sys.stderr, "Error: Can't use --norepopath with multiple repositories"
        sys.exit(1)

    try:
        arches = rpmUtils.arch.getArchList(opts.arch)
        if opts.source:
            arches +=  ['src']
        my.doSackSetup(arches)
    except yum.Errors.RepoError, e:
        print >> sys.stderr, "Error setting up repositories: %s" % e
        # maybe this shouldn't be entirely fatal
        sys.exit(1)
    
    exit_code = 0
    for repo in my.repos.listEnabled():
        reposack = ListPackageSack(my.pkgSack.returnPackages(repoid=repo.id))

        if opts.newest:
            download_list = reposack.returnNewestByNameArch()
        else:
            download_list = list(reposack)
        
        if opts.norepopath:
            local_repo_path = opts.destdir
        else:
            local_repo_path = opts.destdir + '/' + repo.id

        # Ensure we don't traverse out of local_repo_path by dropping any
        # packages whose remote_path is absolute or contains up-level
        # references (unless explicitly allowed).
        # See RHBZ#1600221 for details.
        if not opts.allow_path_traversal:
            newlist = []
            skipped = False
            for pkg in download_list:
                if is_subpath(pkg.remote_path, local_repo_path):
                    newlist.append(pkg)
                    continue
                my.logger.warning(
                    'WARNING: skipping package %s: remote path "%s" not '
                    'within repodir, unsafe to mirror locally'
                    % (pkg, pkg.remote_path)
                )
                skipped = True
            if skipped:
                my.logger.info(
                    'You can enable unsafe remote paths by using '
                    '--allow-path-traversal (see reposync(1) for details)'
                )
            download_list = newlist

        if opts.delete and os.path.exists(local_repo_path):
            current_pkgs = localpkgs(local_repo_path)

            download_set = {}
            for pkg in download_list:
                rpmname = os.path.basename(pkg.remote_path)
                download_set[rpmname] = 1

            for pkg in current_pkgs:
                if pkg in download_set:
                    continue

                if not opts.quiet:
                    my.logger.info("Removing obsolete %s", pkg)
                os.unlink(current_pkgs[pkg]['path'])

        if opts.downloadcomps or opts.downloadmd:

            if not os.path.exists(local_repo_path):
                try:
                    os.makedirs(local_repo_path)
                except IOError, e:
                    my.logger.error("Could not make repo subdir: %s" % e)
                    my.closeRpmDB()
                    sys.exit(1)

            if opts.downloadcomps:
                wanted_types = ['group']
            
            if opts.downloadmd:
                wanted_types = repo.repoXML.fileTypes()

            for ftype in repo.repoXML.fileTypes():
                if ftype in ['primary', 'primary_db', 'filelists',
                             'filelists_db', 'other', 'other_db']:
                    continue
                if ftype not in wanted_types:
                    continue

                try:
                    resultfile = repo.retrieveMD(ftype)
                    basename  = os.path.basename(resultfile)
                    if ftype == 'group' and opts.downloadcomps: # for compat with how --downloadcomps saved the comps file always as comps.xml
                        basename = 'comps.xml'
                    shutil.copyfile(resultfile, "%s/%s" % (local_repo_path, basename))
                except yum.Errors.RepoMDError,e :
                    if not opts.quiet:
                        my.logger.error("Unable to fetch metadata: %s" % e)
                
        remote_size = 0
        local_size  = 0
        if not opts.urls:
            for pkg in download_list:
                local = os.path.join(local_repo_path, pkg.remote_path)
                sz = int(pkg.returnSimple('packagesize'))
                if os.path.exists(local) and os.path.getsize(local) == sz:
                    continue
                remote_size += sz

        if hasattr(urlgrabber.progress, 'text_meter_total_size'):
            urlgrabber.progress.text_meter_total_size(remote_size)

        download_list.sort(sortPkgObj)
        if opts.urls:
            for pkg in download_list:
                local = os.path.join(local_repo_path, pkg.remote_path)
                if not (os.path.exists(local) and my.verifyPkg(local, pkg, False)):
                    print urljoin(pkg.repo.urls[0], pkg.remote_path)
            continue

        # create dest dir
        if not os.path.exists(local_repo_path):
            os.makedirs(local_repo_path)

        # set localpaths
        for pkg in download_list:
            pkg.localpath = os.path.join(local_repo_path, pkg.remote_path)
            pkg.repo.copy_local = True
            pkg.repo.cache = 0
            localdir = os.path.dirname(pkg.localpath)
            if not os.path.exists(localdir):
                os.makedirs(localdir)

        # use downloader from YumBase
        probs = my.downloadPkgs(download_list)
        if probs:
            exit_code = 1
            for key in probs:
                for error in probs[key]:
                    my.logger.error('%s: %s', key, error)

        if opts.gpgcheck:
            for pkg in download_list:
                result, error = my.sigCheckPkg(pkg)
                if result != 0:
                    rpmfn = os.path.basename(pkg.remote_path)
                    if result == 1:
                        my.logger.warning('Removing %s, due to missing GPG key.' % rpmfn)
                    elif result == 2:
                        my.logger.warning('Removing %s due to failed signature check.' % rpmfn)
                    else:
                        my.logger.warning('Removing %s due to failed signature check: %s' % rpmfn)
                    os.unlink(pkg.localpath)
                    exit_code = 1
                    continue

    my.closeRpmDB()
    sys.exit(exit_code)

if __name__ == "__main__":
    main()