# exchange.py - utily to exchange data between repo.

#

# Copyright 2005-2007 Matt Mackall <mpm@selenic.com>

#

# This software may be used and distributed according to the terms of the

# GNU General Public License version 2 or any later version.

from i18n import _

from node import hex

import errno

import util, scmutil, changegroup

import discovery, phases, obsolete, bookmarks

class pushoperation(object):

    """A object that represent a single push operation

    It purpose is to carry push related state and very common operation.

    A new should be created at the begining of each push and discarded

    afterward.

    """

    def __init__(self, repo):

        # repo we push from

        self.repo = repo

def push(repo, remote, force=False, revs=None, newbranch=False):

    '''Push outgoing changesets (limited by revs) from a local

    repository to remote. Return an integer:

      - None means nothing to push

      - 0 means HTTP error

      - 1 means we pushed and remote head count is unchanged *or*

        we have outgoing changesets but refused to push

      - other values as described by addchangegroup()

    '''

    pushop = pushoperation(repo)

    if remote.local():

        missing = set(pushop.repo.requirements) - remote.local().supported

        if missing:

            msg = _("required features are not"

                    " supported in the destination:"

                    " %s") % (', '.join(sorted(missing)))

            raise util.Abort(msg)

    # there are two ways to push to remote repo:

    #

    # addchangegroup assumes local user can lock remote

    # repo (local filesystem, old ssh servers).

    #

    # unbundle assumes local user cannot lock remote repo (new ssh

    # servers, http servers).

    if not remote.canpush():

        raise util.Abort(_("destination does not support push"))

    unfi = pushop.repo.unfiltered()

    def localphasemove(nodes, phase=phases.public):

        """move <nodes> to <phase> in the local source repo"""

        if locallock is not None:

            phases.advanceboundary(pushop.repo, phase, nodes)

        else:

            # repo is not locked, do not change any phases!

            # Informs the user that phases should have been moved when

            # applicable.

            actualmoves = [n for n in nodes if phase < pushop.repo[n].phase()]

            phasestr = phases.phasenames[phase]

            if actualmoves:

    # get local lock as we might write phase data

    locallock = None

    try:

        locallock = pushop.repo.lock()

    except IOError, err:

        if err.errno != errno.EACCES:

            raise

        # source repo cannot be locked.

        # We do not abort the push, but just disable the local phase

        # synchronisation.

        msg = 'cannot lock source repository: %s\n' % err

    try:

        pushop.repo.checkpush(force, revs)

        lock = None

        unbundle = remote.capable('unbundle')

        if not unbundle:

            lock = remote.lock()

        try:

            # discovery

            fci = discovery.findcommonincoming

            commoninc = fci(unfi, remote, force=force)

            common, inc, remoteheads = commoninc

            fco = discovery.findcommonoutgoing

            outgoing = fco(unfi, remote, onlyheads=revs,

                           commoninc=commoninc, force=force)

            if not outgoing.missing:

                # nothing to push

                scmutil.nochangesfound(unfi.ui, unfi, outgoing.excluded)

                ret = None

            else:

                # something to push

                if not force:

                    # if repo.obsstore == False --> no obsolete

                    # then, save the iteration

                    if unfi.obsstore:

                        # this message are here for 80 char limit reason

                        mso = _("push includes obsolete changeset: %s!")

                        mst = "push includes %s changeset: %s!"

                        # plain versions for i18n tool to detect them

                        _("push includes unstable changeset: %s!")

                        _("push includes bumped changeset: %s!")

                        _("push includes divergent changeset: %s!")

                        # If we are to push if there is at least one

                        # obsolete or unstable changeset in missing, at

                        # least one of the missinghead will be obsolete or

                        # unstable. So checking heads only is ok

                        for node in outgoing.missingheads:

                            ctx = unfi[node]

                            if ctx.obsolete():

                                raise util.Abort(mso % ctx)

                            elif ctx.troubled():

                                raise util.Abort(_(mst)

                                                 % (ctx.troubles()[0],

                                                    ctx))

                    discovery.checkheads(unfi, remote, outgoing,

                                         remoteheads, newbranch,

                                         bool(inc), newbm)

                # TODO: get bundlecaps from remote

                bundlecaps = None

                # create a changegroup from local

                if revs is None and not (outgoing.excluded

                                        or pushop.repo.changelog.filteredrevs):

                    # push everything,

                    # use the fast path, no race possible on push

                    bundler = changegroup.bundle10(pushop.repo, bundlecaps)

                    cg = pushop.repo._changegroupsubset(outgoing,

                                                        bundler,

                                                        'push',

                                                        fastpath=True)

                else:

                    cg = pushop.repo.getlocalbundle('push', outgoing,

                                                    bundlecaps)

                # apply changegroup to remote

                if unbundle:

                    # local repo finds heads on server, finds out what

                    # revs it must push. once revs transferred, if server

                    # finds it has different heads (someone else won

                    # commit/push race), server aborts.

                    if force:

                        remoteheads = ['force']

                    # ssh: return remote's addchangegroup()

                    # http: return remote's addchangegroup() or 0 for error

                    ret = remote.unbundle(cg, remoteheads, 'push')

                else:

                    # we return an integer indicating remote head count

                    # change

                    ret = remote.addchangegroup(cg, 'push', pushop.repo.url())

            if ret:

                # push succeed, synchronize target of the push

                cheads = outgoing.missingheads

            elif revs is None:

                # All out push fails. synchronize all common

                cheads = outgoing.commonheads

            else:

                # I want cheads = heads(::missingheads and ::commonheads)

                # (missingheads is revs with secret changeset filtered out)

                #

                # This can be expressed as:

                #     cheads = ( (missingheads and ::commonheads)

                #              + (commonheads and ::missingheads))"

                #              )

                #

                # while trying to push we already computed the following:

                #     common = (::commonheads)

                #     missing = ((commonheads::missingheads) - commonheads)

                #

                # We can pick:

                # * missingheads part of common (::commonheads)

                common = set(outgoing.common)

                nm = pushop.repo.changelog.nodemap

                cheads = [node for node in revs if nm[node] in common]

                # and

                # * commonheads parents on missing

                revset = unfi.set('%ln and parents(roots(%ln))',

                                 outgoing.commonheads,

                                 outgoing.missing)

                cheads.extend(c.node() for c in revset)

            # even when we don't push, exchanging phase data is useful

            remotephases = remote.listkeys('phases')

                and remotephases    # server supports phases

                and ret is None # nothing was pushed

                and remotephases.get('publishing', False)):

                # When:

                # - this is a subrepo push

                # - and remote support phase

                # - and no changeset was pushed

                # - and remote is publishing

                # We may be in issue 3871 case!

                # We drop the possible phase synchronisation done by

                # courtesy to publish changesets possibly locally draft

                # on the remote.

                remotephases = {'publishing': 'True'}

            if not remotephases: # old server or public only repo

                localphasemove(cheads)

                # don't push any phase data as there is nothing to push

            else:

                ana = phases.analyzeremotephases(pushop.repo, cheads,

                                                 remotephases)

                pheads, droots = ana

                ### Apply remote phase on local

                if remotephases.get('publishing', False):

                    localphasemove(cheads)

                else: # publish = False

                    localphasemove(pheads)

                    localphasemove(cheads, phases.draft)

                ### Apply local phase on remote

                # Get the list of all revs draft on remote by public here.

                # XXX Beware that revset break if droots is not strictly

                # XXX root we may want to ensure it is but it is costly

                outdated =  unfi.set('heads((%ln::%ln) and public())',

                                     droots, cheads)

                for newremotehead in outdated:

                    r = remote.pushkey('phases',

                                       newremotehead.hex(),

                                       str(phases.draft),

                                       str(phases.public))

                    if not r:

            obsolete.syncpush(pushop.repo, remote)

        finally:

            if lock is not None:

                lock.release()

    finally:

        if locallock is not None:

            locallock.release()

    return ret