# __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.

"""

from __future__ import absolute_import

import contextlib

import re

from mercurial.i18n import _

from mercurial import (

    branchmap,

    changegroup,

    cmdutil,

    commands,

    context,

    error,

    extensions,

    localrepo,

    lock,

    merge,

    namespaces,

    node,

    obsolete,

    patch,

    phases,

    util,

)

from . import (

    constants,

    revset as topicrevset,

    destination,

    stack,

    topicmap,

    discovery,

)

cmdtable = {}

command = cmdutil.command(cmdtable)

colortable = {'topic.stack.index': 'yellow',

              'topic.stack.state.base': 'dim',

              'topic.stack.state.clean': 'green',

              'topic.stack.index.current': 'cyan', # random pick

              'topic.stack.state.current': 'cyan bold', # random pick

              'topic.stack.desc.current': 'cyan', # random pick

              'topic.stack.state.unstable': 'red',

             }

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.modsetup(ui)

    topicrevset.modsetup(ui)

@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'),

    ] + commands.formatteropts)

def topics(ui, repo, topic='', clear=False, change=None, list=False, **opts):

    """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"))

        return stack.showstack(ui, repo, topic, opts)

    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(changegroup.cg1unpacker, 'apply', cgapply)

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

if util.safehasattr(cmdutil, 'extraexport'):

    cmdutil.extraexport.append('topic')

    cmdutil.extraexportmap['topic'] = _exporttopic