# __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

from mercurial.i18n import _

from mercurial import cmdutil

from mercurial import commands

from mercurial import context

from mercurial import error

from mercurial import extensions

from mercurial import lock

from mercurial import merge

from mercurial import namespaces

from mercurial import obsolete

from mercurial import patch

from mercurial import phases

from mercurial import util

from . import constants

from . import revset as topicrevset

cmdtable = {}

command = cmdutil.command(cmdtable)

def _contexttopic(self):

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

context.basectx.topic = _contexttopic

def _namemap(repo, name):

    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 reposetup(ui, repo):

    orig = repo.__class__

    class topicrepo(repo.__class__):

        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]

            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')

    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'),

])

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

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

    if change:

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

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

        if not topic and not clear:

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

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

            raise util.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())

               newtopic = None if clear else topic

               if fixedextra.get(constants.extrakey, '') == topic:

                   continue

               if clear and constants.extrakey in fixedextra:

                   del fixedextra[constants.extrakey]

               else:

                   fixedextra[constants.extrakey] = topic

               c.parents()

               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)

               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, partial,

                    ancestor=None, mergeancestor=False, labels=None):

    wlock = repo.wlock()

    try:

        ret = orig(repo, node, branchmerge, force, partial, ancestor=ancestor,

                   mergeancestor=mergeancestor, labels=labels)

        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)

topicrevset.modsetup()

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

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

    cmdutil.extraexport.append('topic')

    cmdutil.extraexportmap['topic'] = _exporttopic

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

    cmdutil.extrapreimport.append('topic')

    cmdutil.extrapreimportmap['topic'] = _importtopic

if util.safehasattr(patch, 'patchheadermap'):

    patch.patchheadermap.append(('EXP-Topic', 'topic'))