# -*- coding: utf-8 -*-

# Refactored parts from britney.py, which is/was:
# Copyright (C) 2001-2008 Anthony Towns <ajt@debian.org>
#                         Andreas Barth <aba@debian.org>
#                         Fabio Tranchitella <kobold@debian.org>
# Copyright (C) 2010-2012 Adam D. Barratt <adsb@debian.org>
# Copyright (C) 2012 Niels Thykier <niels@thykier.net>

# 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.


from functools import partial
from itertools import ifilter, ifilterfalse
import re
from consts import BINARIES, PROVIDES

binnmu_re = re.compile(r'^(.*)\+b\d+$')

def same_source(sv1, sv2, binnmu_re=binnmu_re):
    """Check if two version numbers are built from the same source

    This method returns a boolean value which is true if the two
    version numbers specified as parameters are built from the same
    source. The main use of this code is to detect binary-NMU.

    binnmu_re is an optimization to avoid "load global".
    """
    if sv1 == sv2:
        return 1

    m = binnmu_re.match(sv1)
    if m: sv1 = m.group(1)
    m = binnmu_re.match(sv2)
    if m: sv2 = m.group(1)

    if sv1 == sv2:
        return 1

    return 0


def ifilter_except(container, iterable=None):
    """Filter out elements in container

    If given an iterable it returns a filtered iterator, otherwise it
    returns a function to generate filtered iterators.  The latter is
    useful if the same filter has to be (re-)used on multiple
    iterators that are not known on beforehand.
    """
    if iterable is not None:
        return ifilterfalse(container.__contains__, iterable)
    return partial(ifilterfalse, container.__contains__)


def ifilter_only(container, iterable=None):
    """Filter out elements in which are not in container

    If given an iterable it returns a filtered iterator, otherwise it
    returns a function to generate filtered iterators.  The latter is
    useful if the same filter has to be (re-)used on multiple
    iterators that are not known on beforehand.
    """
    if iterable is not None:
        return ifilter(container.__contains__, iterable)
    return partial(ifilter, container.__contains__)


def undo_changes(lundo, systems, sources, binaries,
                 BINARIES=BINARIES, PROVIDES=PROVIDES):
    """Undoes one or more changes to testing

    * lundo is a list of (undo, item)-tuples
    * systems is the britney-py.c system
    * sources is the table of all source packages for all suites
    * binaries is the table of all binary packages for all suites
      and architectures

    The "X=X" parameters are optimizations to avoid "load global"
    in loops.
    """

    # We do the undo process in "4 steps" and each step must be
    # fully completed for each undo-item before starting on the
    # next.
    #
    # see commit:ef71f0e33a7c3d8ef223ec9ad5e9843777e68133 and
    # #624716 for the issues we had when we did not do this.


    # STEP 1
    # undo all the changes for sources
    for (undo, item) in lundo:
        for k in undo['sources']:
            if k[0] == '-':
                del sources["testing"][k[1:]]
            else:
                sources["testing"][k] = undo['sources'][k]

    # STEP 2
    # undo all new binaries (consequence of the above)
    for (undo, item) in lundo:
        if not item.is_removal and item.package in sources[item.suite]:
            for p in sources[item.suite][item.package][BINARIES]:
                binary, arch = p.split("/")
                if item.architecture in ['source', arch]:
                    del binaries["testing"][arch][0][binary]
                    systems[arch].remove_binary(binary)


    # STEP 3
    # undo all other binary package changes (except virtual packages)
    for (undo, item) in lundo:
        for p in undo['binaries']:
            binary, arch = p.split("/")
            if binary[0] == "-":
                del binaries['testing'][arch][0][binary[1:]]
                systems[arch].remove_binary(binary[1:])
            else:
                binaries_t_a = binaries['testing'][arch][0]
                binaries_t_a[binary] = undo['binaries'][p]
                systems[arch].remove_binary(binary)
                systems[arch].add_binary(binary, binaries_t_a[binary][:PROVIDES] + \
                     [", ".join(binaries_t_a[binary][PROVIDES]) or None])

    # STEP 4
    # undo all changes to virtual packages
    for (undo, item) in lundo:
        for p in undo['nvirtual']:
            j, arch = p.split("/")
            del binaries['testing'][arch][1][j]
        for p in undo['virtual']:
            j, arch = p.split("/")
            if j[0] == '-':
                del binaries['testing'][arch][1][j[1:]]
            else:
                binaries['testing'][arch][1][j] = undo['virtual'][p]


def old_libraries_format(libs):
    """Format old libraries in a smart table"""
    libraries = {}
    for i in libs:
        pkg, arch = i.split("/")
        pkg = pkg[1:]
        if pkg in libraries:
            libraries[pkg].append(arch)
        else:
            libraries[pkg] = [arch]
    return "\n".join("  " + k + ": " + " ".join(libraries[k]) for k in libraries) + "\n"