#!/usr/bin/python

import apt
import locale
import datetime
import os
import subprocess
import sys

from apt.utils import *
from gettext import gettext as _
from optparse import OptionParser
from UpdateManager.Core.utils import twrap

CODENAME = subprocess.Popen(["lsb_release","-c","-s"],
                            stdout=subprocess.PIPE).communicate()[0].strip()

def get_maintenance_status(cache, pkgname, supported_tag):
    if supported_tag.endswith("y"):
        supported_for_n_month = 12*int(supported_tag.rstrip("y"))
    elif supported_tag.endswith("m"):
        supported_for_n_month = int(supported_tag.rstrip("m"))
    else:
        raise Exception("Unsupported tag '%s'" % supported_tag)

    # try to figure out the support dates of the release and make
    # sure to look only for stuff in "Ubuntu" and "distro_codename"
    # (to exclude stuff in ubuntu-updates for the support time 
    # calculation because the "Release" file time for that gets
    # updated regularly)
    releasef = get_release_filename_for_pkg(cache, pkgname, 
                                            "Ubuntu", CODENAME)
    if not releasef:
        releasef = get_release_filename_for_pkg(cache, pkgname, 
                                            "Ubuntu", CODENAME + "-updates")

    time_t = get_release_date_from_release_file(releasef)
    # check the release date and show support information
    # based on this
    if not time_t:
        raise Exception("No date tag found")
    release_date = datetime.datetime.fromtimestamp(time_t)
    now = datetime.datetime.now()
    release_age = (now - release_date).days
    
    # mvo: we do not define the end date very precisely
    #      currently this is why it will just display a end
    #      range
    (support_end_year, support_end_month) = get_maintenance_end_date(release_date, supported_for_n_month)
    support_end_month_str = locale.nl_langinfo(getattr(locale,"MON_%d" % support_end_month))
    # check if the support has ended
    support_ended = (now.year >= support_end_year and 
                     now.month > support_end_month)

    # build dict for the argument string
    d = { 'support_tag' : supported_tag,
          'support_end_month_str' : support_end_month_str,
          'support_end_year' : support_end_year }

    if support_ended:
        (False, "%(support_end_month_str)s %(support_end_year)s (%(support_tag)s)" % d)
    return (True, "%(support_end_month_str)s %(support_end_year)s (%(support_tag)s)" % d)
            
if __name__ == "__main__":
    parser = OptionParser()
    parser.add_option("", "--show-unsupported",
                      action="store_true", default=False,
                      help=_("Show unsupported packages on this machine"))
    parser.add_option("", "--show-supported",
                      action="store_true", default=False,
                      help=_("Show supported packages on this machine"))
    parser.add_option("", "--show-all",
                      action="store_true", default=False,
                      help=_("Show all packages with their status"))
    parser.add_option("", "--list",
                      action="store_true", default=False,
                      help=_("Show all packages in a list"))

    (options, args) = parser.parse_args()

    # packages that are not downloadable
    no_candidate = set()

    # packages that we have no support information
    unsupported = set()

    # dict with pkgname : support time
    supported_time_for_pkgname = {}

    # dict with supporttime : set of packagenames
    supported_by_time = {}

    # total count, for statistics
    total = 0

    # analyize
    cache = apt.Cache()
    for pkg in cache:
        if pkg.is_installed:
            total += 1
            if not pkg.candidate or not pkg.candidate.downloadable:
                no_candidate.add(pkg.name)
                continue
            if not "Supported" in pkg.candidate.record:
                unsupported.add(pkg.name)
                continue
            # get support time
            support_tag = pkg.candidate.record["Supported"]
            (still_supported, support_str) = get_maintenance_status(cache, pkg.name, support_tag)
            if not still_supported:
                unsupported.add(pkg.name)
                continue
            supported_time_for_pkgname[pkg.name] = support_tag
            if not support_str in supported_by_time:
                supported_by_time[support_str] = set()
            supported_by_time[support_str].add(pkg.name)

    # output
    print "Support status summary of '%s':" % os.uname()[1]
    print
    for (time, tset) in supported_by_time.iteritems():
        print "You have %s packages (%.1f%%) supported until %s" % (
            len(tset), len(tset) * 100.0 / total, time)
    print

    print "You have %s packages (%.1f%%) that can not/no-longer be downloaded" % (
        len(no_candidate), len(no_candidate) * 100.0 / total)
    print "You have %s packages (%.1f%%) that are unsupported" % (
        len(unsupported), len(unsupported) * 100.0 / total)

    if not (options.show_unsupported or
            options.show_supported or
            options.show_all):
        print
        print "Run with --show-unsupported, --show-supported or --show-all to see more details"

    if options.show_unsupported or options.show_all:
        print
        print "No longer downloadable:"
        print twrap(" ".join(sorted(no_candidate)))
        
        print "Unsupported: "    
        print twrap(" ".join(sorted(unsupported)))
    
    if options.show_supported or options.show_all:
        for (time, tset) in supported_by_time.iteritems():
            print "Supported until %s:" % time
            print twrap(" ".join(sorted(tset)))

    if options.list:
        pkg = max(cache, key=lambda pkg: pkg.is_installed and len(pkg.name))
        field_width = len(pkg.name)
        format_str = "%-"+str(field_width)+"s  %s"
        for pkg in sorted(cache, cmp=lambda a,b: cmp(a.name, b.name)):
            if pkg.is_installed:
                support =  supported_time_for_pkgname.get(pkg.name, _("Unsupported"))
                print format_str % (pkg.name, support)