# states.py - introduce the state concept for mercurial changeset

#

# Copyright 2011 Pierre-Yves David <pierre-yves.david@ens-lyon.org>

#                Logilab SA        <contact@logilab.fr>

#                Augie Fackler     <durin42@gmail.com>

#

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

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

'''introduce the state concept for mercurial changeset

Change can be in the following state:

0 immutable

1 mutable

2 private

name are not fixed yet.

'''

from functools import partial

from mercurial.i18n import _

from mercurial import cmdutil

from mercurial import scmutil

from mercurial import context

from mercurial import revset

from mercurial import templatekw

from mercurial import util

from mercurial import node

from mercurial.node import nullid

from mercurial import discovery

from mercurial import extensions

_NOPULLPUSH=2

STATES = (0, _NOPULLPUSH)

def statename(state):

    return str(STATES)

# util function

#############################

def noderange(repo, revsets):

    return map(repo.changelog.node,

               scmutil.revrange(repo, revsets))

# Patch changectx

#############################

def state(ctx):

    return ctx._repo.nodestate(ctx.node())

context.changectx.state = state

# improve template

#############################

def showstate(ctx, **args):

    return ctx.state()

# New revset predicate

#############################

def revsetpublicheads(repo, subset, x):

    args = revset.getargs(x, 0, 0, 'publicheads takes no arguments')

    heads = map(repo.changelog.rev, repo._statesheads[0])

    heads.sort()

    return heads

def extsetup(ui):

    revset.symbols['publicheads'] = revsetpublicheads

REVSETHEADS = {0: 'publicheads()'}

# New commands

#############################

def cmdsetstate(ui, repo, state, *changesets):

    """turn private changesets into public ones"""

    #assert repo.ui.configbool('private', 'enable', False)

    state = int(state) #for now

    revs = scmutil.revrange(repo, changesets)

    repo.setstate(state, [repo.changelog.node(rev) for rev in revs])

    return 0

cmdtable = {

    'setstate':  (cmdsetstate,   [], _('state <revset>')),

    }

templatekw.keywords['state'] = showstate

def uisetup(ui):

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

        common, heads = orig(repo, *args, **kwargs)

        return common, repo._reducehead(heads)

    def filterprivatein(orig, repo, remote, *args, **kwargs):

        common, anyinc, heads = orig(repo, remote, *args, **kwargs)

        heads = remote._reducehead(heads)

        return common, anyinc, heads

    extensions.wrapfunction(discovery, 'findcommonoutgoing', filterprivateout)

    extensions.wrapfunction(discovery, 'findcommonincoming', filterprivatein)

def reposetup(ui, repo):

    if not repo.local():

        return

    class statefulrepo(repo.__class__):

        def nodestate(self, node):

            rev = self.changelog.rev(node)

            for head in self._publicheads:

                revhead = self.changelog.rev(head)

                if self.changelog.descendant(revhead, rev):

                    return STATES[1]

            return STATES[0]

        @property

        def _publicheads(self):

            if self.ui.configbool('states', 'private', False):

                return self._statesheads[0]

            return self.heads()

        @util.propertycache

        def _statesheads(self):

            return self._readstatesheads()

        def _readstatesheads(self):

            statesheads = {}

            try:

                f = self.opener('publicheads')

                try:

                    heads = sorted([node.bin(n) for n in f.read().split() if n])

                finally:

                    f.close()

            except IOError:

                heads = [nullid]

            statesheads[0] = heads

            return statesheads

        def _writestateshead(self):

            # transaction!

            f = self.opener('publicheads', 'w', atomictemp=True)

            try:

                for h in self._statesheads[0]:

                    f.write(node.hex(h) + '\n')

                f.rename()

            finally:

                f.close()

        def setstate(self, state, nodes):

            """freeze targets changeset and it's ancestors.

            Simplify the list of head."""

            heads = self._statesheads[state]

            olds = heads[:]

            heads.extend(nodes)

            heads[:] = set(heads)

            heads.sort()

            if olds != heads:

                heads[:] = noderange(repo, ["heads(::%s)" % REVSETHEADS[state]])

                heads.sort()

            if olds != heads:

                self._writestateshead()

        def _reducehead(self, candidates):

            selected = set()

            for candidate in candidates:

                rev = self.changelog.rev(candidate)

                ok = True

                for h in self._publicheads:

                    revh = self.changelog.rev(h)

                    if self.changelog.descendant(revh, rev):

                        ok = False

                        selected.add(h)

                if ok:

                    selected.add(candidate)

            return sorted(selected)

    repo.__class__ = statefulrepo