#!/usr/bin/python

import os
import os.path
import re
import string
import sys
import time
import urllib2

def setup_paths():
    check_file = 'lib/python/debian_support.py'
    path = os.getcwd()
    while 1:
        if os.path.exists("%s/%s" % (path, check_file)):
            sys.path = [path + '/lib/python'] + sys.path
            return path
        idx = string.rfind(path, '/')
        if idx == -1:
            raise ImportError, "could not setup paths"
        path = path[0:idx]
os.chdir(setup_paths())

import debian_support

def fetch_dsc(url):
    u = urllib2.urlopen(url)
    assert u.readline()[0] == '-'       # OpenPGP cleartext signature header
    
    def parse(*regexps):
        result = [None] * len(regexps)
        for line in u:
            for i in range(len(regexps)):
                match = regexps[i].match(line)
                if match:
                    result[i] = match.groups()[0]
                    continue
            if line[0] == '-':
                break
        return result

    (source, version)= parse(re.compile("^Source: (\S+)$"),
                             re.compile("^Version: (\S+)$"))
    assert source is not None
    assert version is not None
    return (source, version)

re_title = re.compile(r'<h2>(DSA-\d+-\d+) (\S+) -- (.*)</h2>')
re_date = re.compile(r'^\s+<dd>(\d\d [A-Z][a-z][a-z] \d{4})</dd>$')

re_cve = re.compile('(CVE-\d{4}-\d{4})')
release_headline_re = re.compile(
    r'.*<h3>Debian GNU/Linux \S+ \(([a-z]+)\)</h3>.*')
dscurl_re = re.compile(r'.*"(http://[^">]+\.dsc)".*')

if len(sys.argv) <> 2:
    print "usage: dsa2list DSA-NUMBER"
    sys.exit(1)

try:
    dsa_number = int(sys.argv[1])
except ValueError:
    print `sys.argv[1]`, "is not an integer"
    sys.exit(1)

cve_names = {}
package_notes = []
for year in range(0, 6):
    try:
        url = "http://www.debian.org/security/%d/dsa-%d" % \
              ((time.gmtime().tm_year - year), dsa_number)
        u = urllib2.urlopen(url)
    except urllib2.HTTPError:
        continue

    title = ''
    release = ''
    date = ''
    for line in u.readlines():
        match = re_title.match(line)
        if match:
            title = "%s %s - %s" % match.groups()
            continue

        match = re_date.match(line)
        if match:
            (date,) = match.groups()
        
        for cve in re_cve.findall(line):
            cve_names[cve] = True
        
        match  = release_headline_re.match(line)
        if match:
            (release,) = match.groups()
            continue
            
        match = dscurl_re.match(line)
        if match:
            assert release
            (source, version) = fetch_dsc(match.groups()[0])
            package_notes.append((release, source, version))
    break

assert date
assert title
print "[%s] %s" % (date, title)

cve_names = cve_names.keys()
if cve_names:
    cve_names.sort()
    print "\t{ %s }" % (' '.join(cve_names))

for (release, source, version) in package_notes:
    print "\t[%s] - %s %s" % (release, source, version)