# __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.

"""Adds topic branches. Topic branches are lightweight branches which

dissappear 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 import cmdutil

from mercurial import commands

from mercurial import extensions

from mercurial import namespaces

from mercurial import phases

from mercurial import util

cmdtable = {}

command = cmdutil.command(cmdtable)

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.extra().get('topic', '')

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

        return [t]

    return []

def reposetup(ui, repo):

    orig = repo.__class__

    class topicrepo(repo.__class__):

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

            current = self.currenttopic

            if current:

                ctx.extra()['topic'] = current

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

        @property

        def topics(self):

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

                topics.add(c.extra().get('topic', ''))

            topics.remove('')

            return topics

        @property

        def currenttopic(self):

            return self.vfs.tryread('topic')

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

        repo.names.addnamespace(namespaces.namespace(

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

    repo.__class__ = topicrepo

@command('topics', [

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

])

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

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

    if clear:

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

            repo.vfs.unlink('topic')

        return

    if topic is not None:

        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 updatewrap(orig, ui, repo, *args, **kwargs):

    ret = orig(ui, repo, *args, **kwargs)

    pctx = repo['.']

    if pctx.phase() == phases.public and repo.vfs.exists('topic'):

        repo.vfs.unlink('topic')

    else:

        # inherit the topic of the parent revision

        t = pctx.extra().get('topic', '')

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

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

                f.write(t)

    return ret

extensions.wrapcommand(commands.table, 'update', updatewrap)