# Patch transplanting extension for Mercurial

#

# Copyright 2006, 2007 Brendan Cully <brendan@kublai.com>

#

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

# of the GNU General Public License, incorporated herein by reference.

from mercurial.i18n import _

import os, tempfile

from mercurial import bundlerepo, changegroup, cmdutil, commands, hg, merge

from mercurial import patch, revlog, util

'''patch transplanting tool

This extension allows you to transplant patches from another branch.

Transplanted patches are recorded in .hg/transplant/transplants, as a map

from a changeset hash to its hash in the source repository.

'''

class transplantentry:

    def __init__(self, lnode, rnode):

        self.lnode = lnode

        self.rnode = rnode

class transplants:

    def __init__(self, path=None, transplantfile=None, opener=None):

        self.path = path

        self.transplantfile = transplantfile

        self.opener = opener

        if not opener:

            self.opener = util.opener(self.path)

        self.transplants = []

        self.dirty = False

        self.read()

    def read(self):

        abspath = os.path.join(self.path, self.transplantfile)

        if self.transplantfile and os.path.exists(abspath):

            for line in self.opener(self.transplantfile).read().splitlines():

                lnode, rnode = map(revlog.bin, line.split(':'))

                self.transplants.append(transplantentry(lnode, rnode))

    def write(self):

        if self.dirty and self.transplantfile:

            if not os.path.isdir(self.path):

                os.mkdir(self.path)

            fp = self.opener(self.transplantfile, 'w')

            for c in self.transplants:

                l, r = map(revlog.hex, (c.lnode, c.rnode))

                fp.write(l + ':' + r + '\n')

            fp.close()

        self.dirty = False

    def get(self, rnode):

        return [t for t in self.transplants if t.rnode == rnode]

    def set(self, lnode, rnode):

        self.transplants.append(transplantentry(lnode, rnode))

        self.dirty = True

    def remove(self, transplant):

        del self.transplants[self.transplants.index(transplant)]

        self.dirty = True

class transplanter:

    def __init__(self, ui, repo):

        self.ui = ui

        self.path = repo.join('transplant')

        self.opener = util.opener(self.path)

        self.transplants = transplants(self.path, 'transplants', opener=self.opener)

    def applied(self, repo, node, parent):

        '''returns True if a node is already an ancestor of parent

        or has already been transplanted'''

        if hasnode(repo, node):

            if node in repo.changelog.reachable(parent, stop=node):

                return True

        for t in self.transplants.get(node):

            # it might have been stripped

            if not hasnode(repo, t.lnode):

                self.transplants.remove(t)

                return False

            if t.lnode in repo.changelog.reachable(parent, stop=t.lnode):

                return True

        return False

    def apply(self, repo, source, revmap, merges, opts={}):

        '''apply the revisions in revmap one by one in revision order'''

        revs = revmap.keys()

        revs.sort()

        p1, p2 = repo.dirstate.parents()

        pulls = []

        diffopts = patch.diffopts(self.ui, opts)

        diffopts.git = True

        lock = repo.lock()

        try:

            for rev in revs:

                node = revmap[rev]

                revstr = '%s:%s' % (rev, revlog.short(node))

                if self.applied(repo, node, p1):

                    self.ui.warn(_('skipping already applied revision %s\n') %

                                 revstr)

                    continue

                parents = source.changelog.parents(node)

                if not opts.get('filter'):

                    # If the changeset parent is the same as the wdir's parent,

                    # just pull it.

                    if parents[0] == p1:

                        pulls.append(node)

                        p1 = node

                        continue

                    if pulls:

                        if source != repo:

                            repo.pull(source, heads=pulls, lock=lock)

                        merge.update(repo, pulls[-1], False, False, None,

                                     wlock=wlock)

                        p1, p2 = repo.dirstate.parents()

                        pulls = []

                domerge = False

                if node in merges:

                    # pulling all the merge revs at once would mean we couldn't

                    # transplant after the latest even if transplants before them

                    # fail.

                    domerge = True

                    if not hasnode(repo, node):

                        repo.pull(source, heads=[node], lock=lock)

                if parents[1] != revlog.nullid:

                    self.ui.note(_('skipping merge changeset %s:%s\n')

                                 % (rev, revlog.short(node)))

                    patchfile = None

                else:

                    fd, patchfile = tempfile.mkstemp(prefix='hg-transplant-')

                    fp = os.fdopen(fd, 'w')

                    patch.diff(source, parents[0], node, fp=fp, opts=diffopts)

                    fp.close()

                del revmap[rev]

                if patchfile or domerge:

                    try:

                        n = self.applyone(repo, node, source.changelog.read(node),

                                          patchfile, merge=domerge,

                                          log=opts.get('log'),

                                          filter=opts.get('filter'),

                                          lock=lock, wlock=wlock)

                        if n and domerge:

                            self.ui.status(_('%s merged at %s\n') % (revstr,

                                      revlog.short(n)))

                        elif n:

                            self.ui.status(_('%s transplanted to %s\n') % (revlog.short(node),

                                                                       revlog.short(n)))

                    finally:

                        if patchfile:

                            os.unlink(patchfile)

            if pulls:

                repo.pull(source, heads=pulls, lock=lock)

                merge.update(repo, pulls[-1], False, False, None, wlock=wlock)

        finally:

            self.saveseries(revmap, merges)

            self.transplants.write()

    def filter(self, filter, changelog, patchfile):

        '''arbitrarily rewrite changeset before applying it'''

        self.ui.status('filtering %s\n' % patchfile)

        user, date, msg = (changelog[1], changelog[2], changelog[4])

        fd, headerfile = tempfile.mkstemp(prefix='hg-transplant-')

        fp = os.fdopen(fd, 'w')

        fp.write("# HG changeset patch\n")

        fp.write("# User %s\n" % user)

        fp.write("# Date %d %d\n" % date)

        fp.write(changelog[4])

        fp.close()

        try:

            util.system('%s %s %s' % (filter, util.shellquote(headerfile),

                                   util.shellquote(patchfile)),

                        environ={'HGUSER': changelog[1]},

                        onerr=util.Abort, errprefix=_('filter failed'))

            user, date, msg = self.parselog(file(headerfile))[1:4]

        finally:

            os.unlink(headerfile)

        return (user, date, msg)

    def applyone(self, repo, node, cl, patchfile, merge=False, log=False,

                 filter=None, lock=None, wlock=None):

        '''apply the patch in patchfile to the repository as a transplant'''

        (manifest, user, (time, timezone), files, message) = cl[:5]

        date = "%d %d" % (time, timezone)

        extra = {'transplant_source': node}

        if filter:

            (user, date, message) = self.filter(filter, cl, patchfile)

        if log:

            message += '\n(transplanted from %s)' % revlog.hex(node)

        self.ui.status(_('applying %s\n') % revlog.short(node))

        self.ui.note('%s %s\n%s\n' % (user, date, message))

        if not patchfile and not merge:

            raise util.Abort(_('can only omit patchfile if merging'))

        if patchfile:

            try:

                files = {}

                try:

                    fuzz = patch.patch(patchfile, self.ui, cwd=repo.root,

                                       files=files)

                    if not files:

                        self.ui.warn(_('%s: empty changeset') % revlog.hex(node))

                        return None

                finally:

                    files = patch.updatedir(self.ui, repo, files, wlock=wlock)

            except Exception, inst:

                if filter:

                    os.unlink(patchfile)

                seriespath = os.path.join(self.path, 'series')

                if os.path.exists(seriespath):

                    os.unlink(seriespath)

                p1 = repo.dirstate.parents()[0]

                p2 = node

                self.log(user, date, message, p1, p2, merge=merge)

                self.ui.write(str(inst) + '\n')

                raise util.Abort(_('Fix up the merge and run hg transplant --continue'))

        else:

            files = None

        if merge:

            p1, p2 = repo.dirstate.parents()

            repo.dirstate.setparents(p1, node)

        n = repo.commit(files, message, user, date, lock=lock, wlock=wlock,

                        extra=extra)

        if not merge:

            self.transplants.set(n, node)

        return n

    def resume(self, repo, source, opts=None):

        '''recover last transaction and apply remaining changesets'''

        if os.path.exists(os.path.join(self.path, 'journal')):

            n, node = self.recover(repo)

            self.ui.status(_('%s transplanted as %s\n') % (revlog.short(node),

                                                           revlog.short(n)))

        seriespath = os.path.join(self.path, 'series')

        if not os.path.exists(seriespath):

            self.transplants.write()

            return

        nodes, merges = self.readseries()

        revmap = {}

        for n in nodes:

            revmap[source.changelog.rev(n)] = n

        os.unlink(seriespath)

        self.apply(repo, source, revmap, merges, opts)

    def recover(self, repo):

        '''commit working directory using journal metadata'''

        node, user, date, message, parents = self.readlog()

        merge = len(parents) == 2

        if not user or not date or not message or not parents[0]:

            raise util.Abort(_('transplant log file is corrupt'))

        extra = {'transplant_source': node}

        wlock = repo.wlock()

        p1, p2 = repo.dirstate.parents()

        if p1 != parents[0]:

            raise util.Abort(_('working dir not at transplant parent %s') %

                             revlog.hex(parents[0]))

        if merge:

            repo.dirstate.setparents(p1, parents[1])

        n = repo.commit(None, message, user, date, wlock=wlock, extra=extra)

        if not n:

            raise util.Abort(_('commit failed'))

        if not merge:

            self.transplants.set(n, node)

        self.unlog()

        return n, node

    def readseries(self):

        nodes = []

        merges = []

        cur = nodes

        for line in self.opener('series').read().splitlines():

            if line.startswith('# Merges'):

                cur = merges

                continue

            cur.append(revlog.bin(line))

        return (nodes, merges)

    def saveseries(self, revmap, merges):

        if not revmap:

            return

        if not os.path.isdir(self.path):

            os.mkdir(self.path)

        series = self.opener('series', 'w')

        revs = revmap.keys()

        revs.sort()

        for rev in revs:

            series.write(revlog.hex(revmap[rev]) + '\n')

        if merges:

            series.write('# Merges\n')

            for m in merges:

                series.write(revlog.hex(m) + '\n')

        series.close()

    def parselog(self, fp):

        parents = []

        message = []

        node = revlog.nullid

        inmsg = False

        for line in fp.read().splitlines():

            if inmsg:

                message.append(line)

            elif line.startswith('# User '):

                user = line[7:]

            elif line.startswith('# Date '):

                date = line[7:]

            elif line.startswith('# Node ID '):

                node = revlog.bin(line[10:])

            elif line.startswith('# Parent '):

                parents.append(revlog.bin(line[9:]))

            elif not line.startswith('#'):

                inmsg = True

                message.append(line)

        return (node, user, date, '\n'.join(message), parents)

    def log(self, user, date, message, p1, p2, merge=False):

        '''journal changelog metadata for later recover'''

        if not os.path.isdir(self.path):

            os.mkdir(self.path)

        fp = self.opener('journal', 'w')

        fp.write('# User %s\n' % user)

        fp.write('# Date %s\n' % date)

        fp.write('# Node ID %s\n' % revlog.hex(p2))

        fp.write('# Parent ' + revlog.hex(p1) + '\n')

        if merge:

            fp.write('# Parent ' + revlog.hex(p2) + '\n')

        fp.write(message.rstrip() + '\n')

        fp.close()

    def readlog(self):

        return self.parselog(self.opener('journal'))