# __init__.py - topic extension

#

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

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

"""support for topic branches

Topic branches are lightweight branches which

disappear when changes are finalized.

This is sort of similar to a bookmark, but it applies to a whole

series instead of a single revision.

"""

import functools

import contextlib

import re

from mercurial.i18n import _

from mercurial import branchmap

from mercurial import bundle2

from mercurial import changegroup

from mercurial import cmdutil

from mercurial import commands

from mercurial import context

from mercurial import discovery as discoverymod

from mercurial import error

from mercurial import exchange

from mercurial import extensions

from mercurial import localrepo

from mercurial import lock

from mercurial import merge

from mercurial import namespaces

from mercurial import node

from mercurial import obsolete

from mercurial import patch

from mercurial import phases

from mercurial import util

from mercurial import wireproto

from . import constants

from . import revset as topicrevset

from . import destination

from . import stack

from . import topicmap

from . import discovery

cmdtable = {}

command = cmdutil.command(cmdtable)

testedwith = '3.7'

def _contexttopic(self):

    return self.extra().get(constants.extrakey, '')

context.basectx.topic = _contexttopic

topicrev = re.compile(r'^t\d+$')

def _namemap(repo, name):

    if topicrev.match(name):

        idx = int(name[1:])

        topic = repo.currenttopic

        if not topic:

            raise error.Abort(_('cannot resolve "%s": no active topic') % name)

        revs = list(stack.getstack(repo, topic))

        try:

            r = revs[idx]

        except IndexError:

            msg = _('cannot resolve "%s": topic "%s" has only %d changesets')

            raise error.Abort(msg % (name, topic, len(revs)))

        return [repo[r].node()]

    return [ctx.node() for ctx in

            repo.set('not public() and extra(topic, %s)', name)]

def _nodemap(repo, node):

    ctx = repo[node]

    t = ctx.topic()

    if t and ctx.phase() > phases.public:

        return [t]

    return []

def uisetup(ui):

    destination.setupdest()

@contextlib.contextmanager

def usetopicmap(repo):

    """use awful monkey patching to update the topic cache"""

    oldbranchcache = branchmap.branchcache

    oldfilename = branchmap._filename

    oldread = branchmap.read

    oldcaches =  getattr(repo, '_branchcaches', {})

    try:

        branchmap.branchcache = topicmap.topiccache

        branchmap._filename = topicmap._filename

        branchmap.read = topicmap.readtopicmap

        repo._branchcaches = getattr(repo, '_topiccaches', {})

        yield

        repo._topiccaches = repo._branchcaches

    finally:

        repo._branchcaches = oldcaches

        branchmap.branchcache = oldbranchcache

        branchmap._filename = oldfilename

        branchmap.read = oldread

def cgapply(orig, repo, *args, **kwargs):

    with usetopicmap(repo):

        return orig(repo, *args, **kwargs)

def reposetup(ui, repo):

    orig = repo.__class__

    if not isinstance(repo, localrepo.localrepository):

        return # this can be a peer in the ssh case (puzzling)

    class topicrepo(repo.__class__):

        def _restrictcapabilities(self, caps):

            caps = super(topicrepo, self)._restrictcapabilities(caps)

            caps.add('topics')

            return caps

        def commit(self, *args, **kwargs):

            backup = self.ui.backupconfig('ui', 'allowemptycommit')

            try:

                if repo.currenttopic != repo['.'].topic():

                    # bypass the core "nothing changed" logic

                    self.ui.setconfig('ui', 'allowemptycommit', True)

                return orig.commit(self, *args, **kwargs)

            finally:

                self.ui.restoreconfig(backup)

        def commitctx(self, ctx, error=None):

            if isinstance(ctx, context.workingcommitctx):

                current = self.currenttopic

                if current:

                    ctx.extra()[constants.extrakey] = current

            if (isinstance(ctx, context.memctx) and

                ctx.extra().get('amend_source') and

                ctx.topic() and

                not self.currenttopic):

                # we are amending and need to remove a topic

                del ctx.extra()[constants.extrakey]

            with usetopicmap(self):

                return orig.commitctx(self, ctx, error=error)

        @property

        def topics(self):

            topics = set(['', self.currenttopic])

            for c in self.set('not public()'):

                topics.add(c.topic())

            topics.remove('')

            return topics

        @property

        def currenttopic(self):

            return self.vfs.tryread('topic')

        def branchmap(self, topic=True):

            if not topic:

                super(topicrepo, self).branchmap()

            with usetopicmap(self):

                branchmap.updatecache(self)

            return self._topiccaches[self.filtername]

        def destroyed(self, *args, **kwargs):

            with usetopicmap(self):

                return super(topicrepo, self).destroyed(*args, **kwargs)

        def invalidatecaches(self):

            super(topicrepo, self).invalidatecaches()

            if '_topiccaches' in vars(self.unfiltered()):

                self.unfiltered()._topiccaches.clear()

        def peer(self):

            peer = super(topicrepo, self).peer()

            if getattr(peer, '_repo', None) is not None: # localpeer

                class topicpeer(peer.__class__):

                    def branchmap(self):

                        usetopic = not self._repo.publishing()

                        return self._repo.branchmap(topic=usetopic)

                peer.__class__ = topicpeer

            return peer

    repo.__class__ = topicrepo

    if util.safehasattr(repo, 'names'):

        repo.names.addnamespace(namespaces.namespace(

            'topics', 'topic', namemap=_namemap, nodemap=_nodemap,

            listnames=lambda repo: repo.topics))

@command('topics [TOPIC]', [

    ('', 'clear', False, 'clear active topic if any'),

    ('', 'change', '', 'revset of existing revisions to change topic'),

    ('l', 'list', False, 'show the stack of changeset in the topic'),

    """View current topic, set current topic, or see all topics."""

    if list:

        if clear or change:

            raise error.Abort(_("cannot use --clear or --change with --list"))

    if change:

        if not obsolete.isenabled(repo, obsolete.createmarkersopt):

            raise error.Abort(_('must have obsolete enabled to use --change'))

        if not topic and not clear:

            raise error.Abort('changing topic requires a topic name or --clear')

        if any(not c.mutable() for c in repo.set('%r and public()', change)):

            raise error.Abort("can't change topic of a public change")

        rewrote = 0

        needevolve = False

        l = repo.lock()

        txn = repo.transaction('rewrite-topics')

        try:

           for c in repo.set('%r', change):

               def filectxfn(repo, ctx, path):

                   try:

                       return c[path]

                   except error.ManifestLookupError:

                       return None

               fixedextra = dict(c.extra())

               ui.debug('old node id is %s\n' % node.hex(c.node()))

               ui.debug('origextra: %r\n' % fixedextra)

               newtopic = None if clear else topic

               oldtopic = fixedextra.get(constants.extrakey, None)

               if oldtopic == newtopic:

                   continue

               if clear:

                   del fixedextra[constants.extrakey]

               else:

                   fixedextra[constants.extrakey] = topic

               if 'amend_source' in fixedextra:

                   # TODO: right now the commitctx wrapper in

                   # topicrepo overwrites the topic in extra if

                   # amend_source is set to support 'hg commit

                   # --amend'. Support for amend should be adjusted

                   # to not be so invasive.

                   del fixedextra['amend_source']

               ui.debug('changing topic of %s from %s to %s\n' % (

                   c, oldtopic, newtopic))

               ui.debug('fixedextra: %r\n' % fixedextra)

               mc = context.memctx(

                   repo, (c.p1().node(), c.p2().node()), c.description(),

                   c.files(), filectxfn,

                   user=c.user(), date=c.date(), extra=fixedextra)

               newnode = repo.commitctx(mc)

               ui.debug('new node id is %s\n' % node.hex(newnode))

               needevolve = needevolve or (len(c.children()) > 0)

               obsolete.createmarkers(repo, [(c, (repo[newnode],))])

               rewrote += 1

           txn.close()

        except:

            try:

                txn.abort()

            finally:

                repo.invalidate()

            raise

        finally:

            lock.release(txn, l)

        ui.status('changed topic on %d changes\n' % rewrote)

        if needevolve:

            evolvetarget = 'topic(%s)' % topic if topic else 'not topic()'

            ui.status('please run hg evolve --rev "%s" now\n' % evolvetarget)

    if clear:

        if repo.vfs.exists('topic'):

            repo.vfs.unlink('topic')

        return

    if topic:

        with repo.vfs.open('topic', 'w') as f:

            f.write(topic)

        return

    current = repo.currenttopic

    for t in sorted(repo.topics):

        marker = '*' if t == current else ' '

        ui.write(' %s %s\n' % (marker, t))

def summaryhook(ui, repo):

    t = repo.currenttopic

    if not t:

        return

    # i18n: column positioning for "hg summary"

    ui.write(_("topic:  %s\n") % t)

def commitwrap(orig, ui, repo, *args, **opts):

    if opts.get('topic'):

        t = opts['topic']

        with repo.vfs.open('topic', 'w') as f:

            f.write(t)

    return orig(ui, repo, *args, **opts)

def committextwrap(orig, repo, ctx, subs, extramsg):

    ret = orig(repo, ctx, subs, extramsg)

    t = repo.currenttopic

    if t:

        ret = ret.replace("\nHG: branch",

                          "\nHG: topic '%s'\nHG: branch" % t)

    return ret

def mergeupdatewrap(orig, repo, node, branchmerge, force, *args, **kwargs):

    partial = bool(len(args)) or 'matcher' in kwargs

    wlock = repo.wlock()

    try:

        ret = orig(repo, node, branchmerge, force, *args, **kwargs)

        if not partial and not branchmerge:

            ot = repo.currenttopic

            t = ''

            pctx = repo[node]

            if pctx.phase() > phases.public:

                t = pctx.topic()

            with repo.vfs.open('topic', 'w') as f:

                f.write(t)

            if t and t != ot:

                repo.ui.status(_("switching to topic %s\n") % t)

        return ret

    finally:

        wlock.release()

def _fixrebase(loaded):

    if not loaded:

        return

    def savetopic(ctx, extra):

        if ctx.topic():

            extra[constants.extrakey] = ctx.topic()

    def newmakeextrafn(orig, copiers):

        return orig(copiers + [savetopic])

    rebase = extensions.find("rebase")

    extensions.wrapfunction(rebase, '_makeextrafn', newmakeextrafn)

def _exporttopic(seq, ctx):

    topic = ctx.topic()

    if topic:

        return 'EXP-Topic %s'  % topic

    return None

def _importtopic(repo, patchdata, extra, opts):

    if 'topic' in patchdata:

        extra['topic'] = patchdata['topic']

extensions.afterloaded('rebase', _fixrebase)

entry = extensions.wrapcommand(commands.table, 'commit', commitwrap)

entry[1].append(('t', 'topic', '',

                 _("use specified topic"), _('TOPIC')))

extensions.wrapfunction(cmdutil, 'buildcommittext', committextwrap)

extensions.wrapfunction(merge, 'update', mergeupdatewrap)

extensions.wrapfunction(discoverymod, '_headssummary', discovery._headssummary)

extensions.wrapfunction(wireproto, 'branchmap', discovery.wireprotobranchmap)

extensions.wrapfunction(wireproto, '_capabilities', discovery.wireprotocaps)

extensions.wrapfunction(bundle2, 'handlecheckheads', discovery.handlecheckheads)

bundle2.handlecheckheads.params = frozenset() # we need a proper wrape b2 part stuff

bundle2.parthandlermapping['check:heads'] = bundle2.handlecheckheads

extensions.wrapfunction(exchange, '_pushb2phases', discovery._pushb2phases)

extensions.wrapfunction(changegroup.cg1unpacker, 'apply', cgapply)

exchange.b2partsgenmapping['phase'] = exchange._pushb2phases

topicrevset.modsetup()

cmdutil.summaryhooks.add('topic', summaryhook)