#
# common.py - provides functions which are commonly used by the
#             ubuntu-dev-tools package.
#
# Copyright (C) 2008 Jonathan Davies <jpds@ubuntu.com>
# Copyright (C) 2008 Siegfried-Angel Gevatter Pujals <rainct@ubuntu.com>
#
# Some of the functions are based upon code written by Martin Pitt
# <martin.pitt@ubuntu.com> and Kees Cook <kees@ubuntu.com>.
#
# ##################################################################
#
# 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 3
# 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.
#
# See file /usr/share/common-licenses/GPL for more details.
#
# ##################################################################

import cookielib
import glob
import os.path
import re
import subprocess
import sys
import urllib2

# Clear https_proxy env var as it's not supported in urllib/urllib2; see
# LP #122551
if os.environ.has_key('https_proxy'):
    print >> sys.stderr, "Ignoring https_proxy (no support in urllib/urllib2; see LP #122551)"
    del os.environ['https_proxy']

def mkdir(directory):
    """ Create the given directory and all its parents recursively, but don't
        raise an exception if it already exists. """
    
    path = [x for x in directory.split('/') if x]
    
    for i in xrange(len(path)):
        current_path = '/' + '/'.join(path[:i+1])
        if not os.path.isdir(current_path):
            os.mkdir(current_path)

def readlist(filename, uniq=True):
    """ Read a list of words from the indicated file. """
    
    if not os.path.isfile(filename):
        print 'File "%s" does not exist.' % filename
        return False
    
    content = open(filename).read().replace('\n', ' ').replace(',', ' ')
    
    if not content.strip():
        print 'File "%s" is empty.' % filename
        return False
    
    items = [item for item in content.split() if item]
    
    if uniq:
        items = list(set(items))
    
    return items

def checkReleaseExists(release):
    """ Check that an Ubuntu release exists by opening
        https://launchpad.net/ubuntu/releaseName page on Launchpad.

        If an error is returned; the release does not exist. """
    release = release.split('-')[0] # Remove pocket
    try:
        urllib2.urlopen("https://launchpad.net/ubuntu/%s" % release)
    except urllib2.HTTPError:
        print >> sys.stderr, "The Ubuntu '%s' release does not appear to " \
            "exist on Launchpad." % release
        sys.exit(1)
    except urllib2.URLError, error: # Other error (NXDOMAIN, ...)
        (_, reason) = error.reason
        print >> sys.stderr, "Error while checking for Ubuntu '%s' " \
            "release on Launchpad: %s." % (release, reason)
        sys.exit(1)

def checkSourceExists(package, release):
    """ Check that a package exists by opening its
        https://launchpad.net/ubuntu/+source/package page.
        
        Return the page and version in release. """
    if '-' in release:
        (release, pocket) = release.split('-', 1)
    else:
        pocket = 'release'

    try:
        page = urllib2.urlopen('https://launchpad.net/ubuntu/+source/' + package).read()

        m = re.search('<td>%s</td>\s*\n.*"/ubuntu/%s/\+source/%s/(\d[^"]+)"' % (
                pocket, release, package.replace('+', '\+')), page)
        if not m:
            print >> sys.stderr, "Unable to find source package '%s' in " \
                "the %s-%s pocket." % (package, release.capitalize(), pocket)
            sys.exit(1)
    except urllib2.HTTPError, error: # Raised on 404.
        if error.code == 404:
            print >> sys.stderr, "The source package '%s' does not appear to " \
                "exist in Ubuntu." % package
        else: # Other error code, probably Launchpad malfunction.
            print >> sys.stderr, "Error while checking Launchpad for Ubuntu " \
                "package: %s." % error.code
        sys.exit(1) # Exit. Error encountered.
    except urllib2.URLError, error: # Other error (NXDOMAIN, ...)
        (_, reason) = error.reason
        print >> sys.stderr, "Error while checking Launchpad for Ubuntu " \
            "package: %s." % reason
        sys.exit(1)

    # Get package version.
    version = m.group(1)

    return page, version

def prepareLaunchpadCookie():
    """ Search for a cookie file in the places as defined by try_globs.
        We shall use this cookie for authentication with Launchpad. """
    
    # We do not have our cookie.
    launchpad_cookiefile = None
    # Look in common locations.
    try_globs = ('~/.lpcookie.txt', '~/.mozilla/*/*/cookies.sqlite',
        '~/.mozilla/*/*/cookies.txt')
    
    cookie_file_list = []
    if launchpad_cookiefile == None:
        for try_glob in try_globs:
            try:
                cookie_file_list += glob.glob(os.path.expanduser(try_glob))
            except:
                pass

    for cookie_file in cookie_file_list:
        launchpad_cookiefile = _check_for_launchpad_cookie(cookie_file)
        if launchpad_cookiefile != None:
            break

    # Unable to find a correct file.
    if launchpad_cookiefile == None:
        print >> sys.stderr, "Could not find cookie file for Launchpad. "
        print >> sys.stderr, "Looked in: %s" % ", ".join(try_globs)
        print >> sys.stderr, "You should be able to create a valid file by " \
            "logging into Launchpad with Firefox."
        sys.exit(1)

    return launchpad_cookiefile

def _check_for_launchpad_cookie(cookie_file):
    # Found SQLite file? Parse information from it.
    if 'cookies.sqlite' in cookie_file:
        import sqlite3 as sqlite

        con = sqlite.connect(cookie_file)
        cur = con.cursor()
        try:
            cur.execute("select host, path, isSecure, expiry, name, value from moz_cookies where host like ?", ['%%launchpad%%'])
        except sqlite.OperationalError:
            print 'Warning: Database "%s" is locked; ignoring it.' % cookie_file
            return None

        # No matching cookies?  Abort.
        items = cur.fetchall()
        if len(items) == 0:
            return None

        ftstr = ["FALSE", "TRUE"]

        # This shall be where our new cookie file lives - at ~/.lpcookie.txt
        newLPCookieLocation = os.path.expanduser("~/.lpcookie.txt")

        # Open file for writing.
        try:
            newLPCookie = open(newLPCookieLocation, 'w')
            # For security reasons, change file mode to write and read
            # only by owner.
            os.chmod(newLPCookieLocation, 0600)
            newLPCookie.write("# HTTP Cookie File for Launchpad.\n") # Header.

            for item in items:
                # Write entries.
                newLPCookie.write("%s\t%s\t%s\t%s\t%s\t%s\t%s\n" % (
                    item[0], ftstr[item[0].startswith('.')], item[1],
                    ftstr[item[2]], item[3], item[4], item[5]))
        finally:
            newLPCookie.close()     # And close file.

        return newLPCookieLocation
    else:
        if open(cookie_file).read().find('launchpad.net') != -1:
            return cookie_file

    return None

def setupLaunchpadUrlOpener(cookie):
    """ Build HTML opener with cookie file. """

    # Attempt to load our cookie file.
    try:
        cj = cookielib.MozillaCookieJar()
        cj.load(cookie)
    except cookielib.LoadError, error:
        print "Unable to load cookie file: %s (%s)" % (cookie, error)
        sys.exit(1)

    # Add cookie to our URL opener.
    urlopener = urllib2.build_opener()
    urlopener.add_handler(urllib2.HTTPCookieProcessor(cj))
    
    return urlopener

def isLPTeamMember(team):
    """ Checks if the user is a member of a certain team on Launchpad.

        We do this by opening the team page on Launchpad and checking if the
        text "You are not a member of this team" is present using the
        user's cookie file for authentication.

        If the user is a member of the team: return True.
        If the user is not a member of the team: return False.
    """

    # TODO: Check if launchpadlib may be a better way of doing this.

    # Prepare cookie.
    cookieFile = prepareLaunchpadCookie()
    # Prepare URL opener.
    urlopener = setupLaunchpadUrlOpener(cookieFile)

    # Try to open the Launchpad team page:
    try:
        lpTeamPage = urlopener.open("https://launchpad.net/~%s" % team).read()
    except urllib2.HTTPError, error:
        print >> sys.stderr, "Unable to connect to Launchpad. Received a %s." % error.code
        sys.exit(1)

    # Check if text is present in page.
    if ("You are not a member of this team") in lpTeamPage:
        return False

    return True

def packageComponent(package, release):
    madison = subprocess.Popen(['rmadison', '-u', 'ubuntu', '-a', 'source', \
        '-s', release, package], stdout = subprocess.PIPE)
    out = madison.communicate()[0]
    assert (madison.returncode == 0)
    
    for l in out.splitlines():
        (pkg, version, rel, builds) = l.split('|')
        component = 'main'
        if rel.find('/') != -1: 
            component = rel.split('/')[1]

    return component.strip()