# discovery.py - protocol changeset discovery functions

#

# Copyright 2010 Olivia Mackall <olivia@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.

import functools

from .i18n import _

from .node import (

    hex,

    short,

)

from . import (

    bookmarks,

    branchmap,

    error,

    obsolete,

    phases,

    pycompat,

    scmutil,

    setdiscovery,

    treediscovery,

    util,

)

def findcommonincoming(repo, remote, heads=None, force=False, ancestorsof=None):

    """Return a tuple (common, anyincoming, heads) used to identify the common

    subset of nodes between repo and remote.

    "common" is a list of (at least) the heads of the common subset.

    "anyincoming" is testable as a boolean indicating if any nodes are missing

      locally. If remote does not support getbundle, this actually is a list of

      roots of the nodes that would be incoming, to be supplied to

      changegroupsubset. No code except for pull should be relying on this fact

      any longer.

    "heads" is either the supplied heads, or else the remote's heads.

    "ancestorsof" if not None, restrict the discovery to a subset defined by

      these nodes. Changeset outside of this set won't be considered (but may

      still appear in "common").

    If you pass heads and they are all known locally, the response lists just

    these heads in "common" and in "heads".

    Please use findcommonoutgoing to compute the set of outgoing nodes to give

    extensions a good hook into outgoing.

    """

    if not remote.capable(b'getbundle'):

        return treediscovery.findcommonincoming(repo, remote, heads, force)

    if heads:

        knownnode = repo.changelog.hasnode  # no nodemap until it is filtered

        if all(knownnode(h) for h in heads):

            return (heads, False, heads)

    res = setdiscovery.findcommonheads(

        repo.ui,

        repo,

        remote,

        abortwhenunrelated=not force,

        ancestorsof=ancestorsof,

    )

    common, anyinc, srvheads = res

    if heads and not anyinc:

        # server could be lying on the advertised heads

        has_node = repo.changelog.hasnode

        anyinc = any(not has_node(n) for n in heads)

    return (list(common), anyinc, heads or list(srvheads))

class outgoing:

    """Represents the result of a findcommonoutgoing() call.

    Members:

      ancestorsof is a list of the nodes whose ancestors are included in the

      outgoing operation.

      missing is a list of those ancestors of ancestorsof that are present in

      local but not in remote.

      common is a set containing revs common between the local and the remote

      repository (at least all of those that are ancestors of ancestorsof).

      commonheads is the list of heads of common.

      excluded is the list of missing changeset that shouldn't be sent

      remotely.

    Some members are computed on demand from the heads, unless provided upfront

    by discovery."""

    def __init__(

        self, repo, commonheads=None, ancestorsof=None, missingroots=None

    ):

        # at least one of them must not be set

        assert None in (commonheads, missingroots)

        cl = repo.changelog

        if ancestorsof is None:

            ancestorsof = cl.heads()

        if missingroots:

            discbases = []

            for n in missingroots:

                discbases.extend([p for p in cl.parents(n) if p != repo.nullid])

            # TODO remove call to nodesbetween.

            # TODO populate attributes on outgoing instance instead of setting

            # discbases.

            csets, roots, heads = cl.nodesbetween(missingroots, ancestorsof)

            included = set(csets)

            ancestorsof = heads

            commonheads = [n for n in discbases if n not in included]

        elif not commonheads:

            commonheads = [repo.nullid]

        self.commonheads = commonheads

        self.ancestorsof = ancestorsof

        self._revlog = cl

        self._common = None

        self._missing = None

        self.excluded = []

    def _computecommonmissing(self):

        sets = self._revlog.findcommonmissing(

            self.commonheads, self.ancestorsof

        )

        self._common, self._missing = sets

    @util.propertycache

    def common(self):

        if self._common is None:

            self._computecommonmissing()

        return self._common

    @util.propertycache

    def missing(self):

        if self._missing is None:

            self._computecommonmissing()

        return self._missing

def findcommonoutgoing(

    repo, other, onlyheads=None, force=False, commoninc=None, portable=False

):

    """Return an outgoing instance to identify the nodes present in repo but

    not in other.

    If onlyheads is given, only nodes ancestral to nodes in onlyheads

    (inclusive) are included. If you already know the local repo's heads,

    passing them in onlyheads is faster than letting them be recomputed here.

    If commoninc is given, it must be the result of a prior call to

    findcommonincoming(repo, other, force) to avoid recomputing it here.

    If portable is given, compute more conservative common and ancestorsof,

    to make bundles created from the instance more portable."""

    # declare an empty outgoing object to be filled later

    og = outgoing(repo, None, None)

    # get common set if not provided

    if commoninc is None:

        commoninc = findcommonincoming(

            repo, other, force=force, ancestorsof=onlyheads

        )

    og.commonheads, _any, _hds = commoninc

    # compute outgoing

    mayexclude = repo._phasecache.phaseroots[phases.secret] or repo.obsstore

    if not mayexclude:

        og.ancestorsof = onlyheads or repo.heads()

    elif onlyheads is None:

        # use visible heads as it should be cached

        og.ancestorsof = repo.filtered(b"served").heads()

        og.excluded = [ctx.node() for ctx in repo.set(b'secret() or extinct()')]

    else:

        # compute common, missing and exclude secret stuff

        sets = repo.changelog.findcommonmissing(og.commonheads, onlyheads)

        og._common, allmissing = sets

        og._missing = missing = []

        og.excluded = excluded = []

        for node in allmissing:

            ctx = repo[node]

            if ctx.phase() >= phases.secret or ctx.extinct():

                excluded.append(node)

            else:

                missing.append(node)

        if len(missing) == len(allmissing):

            ancestorsof = onlyheads

        else:  # update missing heads

            ancestorsof = phases.newheads(repo, onlyheads, excluded)

        og.ancestorsof = ancestorsof

    if portable:

        # recompute common and ancestorsof as if -r<rev> had been given for

        # each head of missing, and --base <rev> for each head of the proper

        # ancestors of missing

        og._computecommonmissing()

        cl = repo.changelog

        missingrevs = {cl.rev(n) for n in og._missing}

        og._common = set(cl.ancestors(missingrevs)) - missingrevs

        commonheads = set(og.commonheads)

        og.ancestorsof = [h for h in og.ancestorsof if h not in commonheads]

    return og

def _headssummary(pushop):

    """compute a summary of branch and heads status before and after push

    return {'branch': ([remoteheads], [newheads],

                       [unsyncedheads], [discardedheads])} mapping

    - branch: the branch name,

    - remoteheads: the list of remote heads known locally

                   None if the branch is new,

    - newheads: the new remote heads (known locally) with outgoing pushed,

    - unsyncedheads: the list of remote heads unknown locally,

    - discardedheads: the list of heads made obsolete by the push.

    """

    repo = pushop.repo.unfiltered()

    remote = pushop.remote

    outgoing = pushop.outgoing

    cl = repo.changelog

    headssum = {}

    missingctx = set()

    # A. Create set of branches involved in the push.

    branches = set()

    for n in outgoing.missing:

        ctx = repo[n]

        missingctx.add(ctx)

        branches.add(ctx.branch())

    with remote.commandexecutor() as e:

        remotemap = e.callcommand(b'branchmap', {}).result()

    knownnode = cl.hasnode  # do not use nodemap until it is filtered

    # A. register remote heads of branches which are in outgoing set

    for branch, heads in remotemap.items():

        # don't add head info about branches which we don't have locally

        if branch not in branches:

            continue

        known = []

        unsynced = []

        for h in heads:

            if knownnode(h):

                known.append(h)

            else:

                unsynced.append(h)

        headssum[branch] = (known, list(known), unsynced)

    # B. add new branch data

    for branch in branches:

        if branch not in headssum:

            headssum[branch] = (None, [], [])

    # C. Update newmap with outgoing changes.

    # This will possibly add new heads and remove existing ones.

    newmap = branchmap.remotebranchcache(

        repo,

        (

            (branch, heads[1])

            for branch, heads in headssum.items()

            if heads[0] is not None

        ),

    )

    newmap.update(repo, (ctx.rev() for ctx in missingctx))

    for branch, newheads in newmap.items():

        headssum[branch][1][:] = newheads

    for branch, items in headssum.items():

        for l in items:

            if l is not None:

                l.sort()

        headssum[branch] = items + ([],)

    # If there are no obsstore, no post processing are needed.

    if repo.obsstore:

        torev = repo.changelog.rev

        futureheads = {torev(h) for h in outgoing.ancestorsof}

        futureheads |= {torev(h) for h in outgoing.commonheads}

        allfuturecommon = repo.changelog.ancestors(futureheads, inclusive=True)

        for branch, heads in sorted(pycompat.iteritems(headssum)):

            remoteheads, newheads, unsyncedheads, placeholder = heads

            result = _postprocessobsolete(pushop, allfuturecommon, newheads)

            headssum[branch] = (

                remoteheads,

                sorted(result[0]),

                unsyncedheads,

                sorted(result[1]),

            )

    return headssum

def _oldheadssummary(repo, remoteheads, outgoing, inc=False):

    """Compute branchmapsummary for repo without branchmap support"""

    # 1-4b. old servers: Check for new topological heads.

    # Construct {old,new}map with branch = None (topological branch).

    # (code based on update)

    knownnode = repo.changelog.hasnode  # no nodemap until it is filtered

    oldheads = sorted(h for h in remoteheads if knownnode(h))

    # all nodes in outgoing.missing are children of either:

    # - an element of oldheads

    # - another element of outgoing.missing

    # - nullrev

    # This explains why the new head are very simple to compute.

    r = repo.set(b'heads(%ln + %ln)', oldheads, outgoing.missing)

    newheads = sorted(c.node() for c in r)

    # set some unsynced head to issue the "unsynced changes" warning

    if inc:

        unsynced = [None]

    else:

        unsynced = []

    return {None: (oldheads, newheads, unsynced, [])}

def _nowarnheads(pushop):

    # Compute newly pushed bookmarks. We don't warn about bookmarked heads.

    repo = pushop.repo.unfiltered()

    remote = pushop.remote

    localbookmarks = repo._bookmarks

    with remote.commandexecutor() as e:

        remotebookmarks = e.callcommand(

            b'listkeys',

            {

                b'namespace': b'bookmarks',

            },

        ).result()

    bookmarkedheads = set()

    # internal config: bookmarks.pushing

    newbookmarks = [

        localbookmarks.expandname(b)

        for b in pushop.ui.configlist(b'bookmarks', b'pushing')

    ]

    for bm in localbookmarks:

        rnode = remotebookmarks.get(bm)

        if rnode and rnode in repo:

            lctx, rctx = repo[localbookmarks[bm]], repo[rnode]

            if bookmarks.validdest(repo, rctx, lctx):

                bookmarkedheads.add(lctx.node())

        else:

            if bm in newbookmarks and bm not in remotebookmarks:

                bookmarkedheads.add(localbookmarks[bm])

    return bookmarkedheads

def checkheads(pushop):

    """Check that a push won't add any outgoing head

    raise StateError error and display ui message as needed.

    """

    repo = pushop.repo.unfiltered()

    remote = pushop.remote

    outgoing = pushop.outgoing

    remoteheads = pushop.remoteheads

    newbranch = pushop.newbranch

    inc = bool(pushop.incoming)

    # Check for each named branch if we're creating new remote heads.

    # To be a remote head after push, node must be either:

    # - unknown locally

    # - a local outgoing head descended from update

    # - a remote head that's known locally and not

    #   ancestral to an outgoing head

    if remoteheads == [repo.nullid]:

        # remote is empty, nothing to check.

        return

    if remote.capable(b'branchmap'):

        headssum = _headssummary(pushop)

    else:

        headssum = _oldheadssummary(repo, remoteheads, outgoing, inc)

    pushop.pushbranchmap = headssum

    newbranches = [

        branch for branch, heads in headssum.items() if heads[0] is None

    ]

    # 1. Check for new branches on the remote.