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

#

# Copyright 2011 Peter Arrenbrecht <peter.arrenbrecht@gmail.com>

#                Logilab SA        <contact@logilab.fr>

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

#

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

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

'''A set of command to make changeset evolve.'''

from mercurial import cmdutil

from mercurial import scmutil

from mercurial import node

from mercurial import error

from mercurial import extensions

from mercurial import commands

from mercurial import bookmarks

from mercurial import phases

from mercurial import context

from mercurial import commands

from mercurial import util

from mercurial.i18n import _

from mercurial.commands import walkopts, commitopts, commitopts2, logopt

from mercurial import hg

### util function

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

def noderange(repo, revsets):

    """The same as revrange but return node"""

    return map(repo.changelog.node,

               scmutil.revrange(repo, revsets))

### extension check

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

def extsetup(ui):

    try:

        obsolete = extensions.find('obsolete')

    except KeyError:

        raise error.Abort(_('evolution extension require obsolete extension.'))

    try:

        rebase = extensions.find('rebase')

    except KeyError:

        raise error.Abort(_('evolution extension require rebase extension.'))

### changeset rewriting logic

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

def rewrite(repo, old, updates, head, newbases, commitopts):

    if len(old.parents()) > 1: #XXX remove this unecessary limitation.

        raise error.Abort(_('cannot amend merge changesets'))

    base = old.p1()

    bm = bookmarks.readcurrent(repo)

    wlock = repo.wlock()

    try:

        # commit a new version of the old changeset, including the update

        # collect all files which might be affected

        files = set(old.files())

        for u in updates:

            files.update(u.files())

        # prune files which were reverted by the updates

        def samefile(f):

            if f in head.manifest():

                a = head.filectx(f)

                if f in base.manifest():

                    b = base.filectx(f)

                    return (a.data() == b.data()

                            and a.flags() == b.flags()

                            and a.renamed() == b.renamed())

                else:

                    return False

            else:

                return f not in base.manifest()

        files = [f for f in files if not samefile(f)]

        # commit version of these files as defined by head

        headmf = head.manifest()

        def filectxfn(repo, ctx, path):

            if path in headmf:

                return head.filectx(path)

            raise IOError()

        if commitopts.get('message') and commitopts.get('logfile'):

            raise util.Abort(_('options --message and --logfile are mutually'

                               ' exclusive'))

        if commitopts.get('logfile'):

            message= open(commitopts['logfile']).read()

        elif commitopts.get('message'):

            message = commitopts['message']

        else:

            message = old.description()

        new = context.memctx(repo,

                             parents=newbases,

                             text=message,

                             files=files,

                             filectxfn=filectxfn,

                             user=commitopts.get('user') or None,

                             date=commitopts.get('date') or None,

                             extra=commitopts.get('extra') or None)

        if commitopts.get('edit'):

            new._text = cmdutil.commitforceeditor(repo, new, [])

        newid = repo.commitctx(new)

        new = repo[newid]

        # update the bookmark

        if bm:

            repo._bookmarks[bm] = newid

            bookmarks.write(repo)

        # add evolution metadata

        repo.addobsolete(new.node(), old.node())

        for u in updates:

            repo.addobsolete(u.node(), old.node())

            repo.addobsolete(new.node(), u.node())

        oldbookmarks = repo.nodebookmarks(old.node())

        for book in oldbookmarks:

            repo._bookmarks[book] = new.node()

        if oldbookmarks:

            bookmarks.write(repo)

    finally:

        wlock.release()

    return newid

def relocate(repo, orig, dest):

    """rewrite <rev> on dest"""

    try:

        rebase = extensions.find('rebase')

        # dummy state to trick rebase node

        assert orig.p2().rev() == node.nullrev, 'no support yet'

        destbookmarks = repo.nodebookmarks(dest.node())

        cmdutil.duplicatecopies(repo, orig.node(), dest.node())

        rebase.rebasenode(repo, orig.node(), dest.node(), {node.nullrev: node.nullrev})

        nodenew = rebase.concludenode(repo, orig.node(), dest.node(), node.nullid)

        nodesrc = orig.node()

        repo.addobsolete(nodenew, nodesrc)

        phases.retractboundary(repo, repo[nodesrc].phase(), [nodenew])

        oldbookmarks = repo.nodebookmarks(nodesrc)

        for book in oldbookmarks:

            repo._bookmarks[book] = nodenew

        for book in destbookmarks: # restore bookmark that rebase move

            repo._bookmarks[book] = dest.node()

        if oldbookmarks or destbookmarks:

            bookmarks.write(repo)

    except util.Abort:

        # Invalidate the previous setparents

        repo.dirstate.invalidate()

        raise

### new command

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

cmdtable = {}

command = cmdutil.command(cmdtable)

@command('^stabilize',

    [

     ('n', 'dry-run', False, 'Do nothing but printing what should be done')

    ],

    '')

def stabilize(ui, repo, **opts):

    """move changeset out of they unstable state"""

    obsolete = extensions.find('obsolete')

    unstable = list(repo.set('unstable()'))

    if not unstable:

        ui.write_err(_('no unstable changeset\n'))

        return 1

    node = unstable[0]

    obs = node.parents()[0]

    if not obs.obsolete():

        obs = node.parents()[1]

    assert obs.obsolete()

    newer = obsolete.newerversion(repo, obs.node())

    if len(newer) > 1:

        ui.write_err(_("conflict rewriting. can't choose destination\n"))

        return 2

    targets = newer[0]

    if not targets:

        ui.write_err(_("does not handle kill parent yet\n"))

        return 2

    if len(targets) > 1:

        ui.write_err(_("does not handle splitted parent yet\n"))

        return 2

    target = targets[0]

    displayer = cmdutil.show_changeset(ui, repo, {'template': shorttemplate})

    target = repo[target]

    repo.ui.status(_('move:'))

    displayer.show(node)

    repo.ui.status(_('atop:'))

    displayer.show(target)

    todo= 'hg rebase -Dr %s -d %s\n' % (node, target)

    if opts['dry_run']:

        repo.ui.status(todo)

    else:

        repo.ui.note(todo)

        lock = repo.lock()

        try:

            relocate(repo, node, target)

        finally:

            lock.release()

shorttemplate = '[{rev}] {desc|firstline}\n'

@command('^gdown',

    [],

    'update to working directory parent an display summary lines')

def cmdgdown(ui, repo):

    wkctx = repo[None]

    wparents = wkctx.parents()

    if len(wparents) != 1:

        raise util.Abort('merge in progress')

    parents = wparents[0].parents()

    displayer = cmdutil.show_changeset(ui, repo, {'template': shorttemplate})

    if len(parents) == 1:

        p = parents[0]

        hg.update(repo, p.rev())

        displayer.show(p)

        return 0

    else:

        for p in parents:

            displayer.show(p)

        ui.warn(_('multiple parents, explicitly update to one\n'))

        return 1

@command('^gup',

    [],

    'update to working directory children an display summary lines')

def cmdup(ui, repo):

    wkctx = repo[None]

    wparents = wkctx.parents()

    if len(wparents) != 1:

        raise util.Abort('merge in progress')

    children = [ctx for ctx in wparents[0].children() if not ctx.obsolete()]

    displayer = cmdutil.show_changeset(ui, repo, {'template': shorttemplate})

    if not children:

        ui.warn(_('No non-obsolete children\n'))

        return 1

    if len(children) == 1:

        c = children[0]

        hg.update(repo, c.rev())

        displayer.show(c)

        return 0

    else:

        for c in children:

            displayer.show(c)

        ui.warn(_('Multiple non-obsolete children, explicitly update to one\n'))

        return 1

@command('^kill',

    [

    ('n', 'new', [], _("New changeset that justify this one to be killed"))

    ],

    '<revs>')

def kill(ui, repo, *revs, **opts):

    """mark a changeset as obsolete

    This update the parent directory to a not-killed parent if the current

    working directory parent are killed.

    XXX bookmark support

    XXX handle merge

    XXX check immutable first

    """

    wlock = repo.wlock()

    try:

        new = opts['new']

        targetnodes = set(noderange(repo, revs))

        if not new:

            new = [node.nullid]

        for n in targetnodes:

            if not repo[n].mutable():

                ui.warn(_("Can't kill immutable changeset %s") % repo[n])

            else:

                for ne in new:

                    repo.addobsolete(ne, n)

        # update to an unkilled parent

        wdp = repo['.']

        newnode = wdp

        while newnode.obsolete():

            newnode = newnode.parents()[0]

        if newnode.node() != wdp.node():

            commands.update(ui, repo, newnode.rev())

            ui.status(_('working directory now at %s\n') % newnode)

    finally:

        wlock.release()

@command('^amend',

    [('A', 'addremove', None,

     _('mark new/missing files as added/removed before committing')),

    ('n', 'note', '',

     _('use text as commit message for this update')),

    ('c', 'change', '',

     _('specifies the changeset to amend'), _('REV')),

    ('b', 'branch', '',

     _('specifies a branch for the new.'), _('REV')),

    ('e', 'edit', False,

     _('edit commit message.'), _('')),

    ] + walkopts + commitopts + commitopts2,

    _('[OPTION]... [FILE]...'))

def amend(ui, repo, *pats, **opts):

    """combine a changeset with updates and replace it with a new one

    Commits a new changeset incorporating both the changes to the given files

    and all the changes from the current parent changeset into the repository.

    See :hg:`commit` for details about committing changes.

    If you don't specify -m, the parent's message will be reused.

    If you specify --change, amend additionally considers all changesets between

    the indicated changeset and the working copy parent as updates to be subsumed.

    This allows you to commit updates manually first. As a special shorthand you

    can say `--amend .` instead of '--amend p1(p1())', which subsumes your latest

    commit as an update of its parent.

    Behind the scenes, Mercurial first commits the update as a regular child

    of the current parent. Then it creates a new commit on the parent's parents

    with the updated contents. Then it changes the working copy parent to this

    new combined changeset. Finally, the old changeset and its update are hidden

    from :hg:`log` (unless you use --hidden with log).

    Returns 0 on success, 1 if nothing changed.

    """

    # determine updates to subsume

    change = opts.get('change')

    if change == '.':

        change = 'p1(p1())'

    old = scmutil.revsingle(repo, change)

    branch = opts.get('branch')

    if branch:

        opts.setdefault('extra', {})['branch'] = branch

    else:

        if old.branch() != 'default':

            opts.setdefault('extra', {})['branch'] = old.branch()

    lock = repo.lock()

    try:

        wlock = repo.wlock()

        try:

            if not old.phase():

                raise util.Abort(_("can not rewrite immutable changeset %s") % old)

            # commit current changes as update

            # code copied from commands.commit to avoid noisy messages

            ciopts = dict(opts)

            ciopts.pop('message', None)

            ciopts.pop('logfile', None)

            ciopts['message'] = opts.get('note') or ('amends %s' % old.hex())

            e = cmdutil.commiteditor

            def commitfunc(ui, repo, message, match, opts):

                return repo.commit(message, opts.get('user'), opts.get('date'), match,

                                   editor=e)

            cmdutil.commit(ui, repo, commitfunc, pats, ciopts)

            # find all changesets to be considered updates

            cl = repo.changelog

            head = repo['.']

            updatenodes = set(cl.nodesbetween(roots=[old.node()],

                                              heads=[head.node()])[0])

            updatenodes.remove(old.node())