# darcs support for the convert extension

from mercurial.i18n import _

from mercurial import util

import os, shutil, tempfile

# The naming drift of ElementTree is fun!

try: from xml.etree.cElementTree import ElementTree

except ImportError:

    try: from xml.etree.ElementTree import ElementTree

    except ImportError:

        try: from elementtree.cElementTree import ElementTree

        except ImportError:

            try: from elementtree.ElementTree import ElementTree

            except ImportError: ElementTree = None

class darcs_source(converter_source):

    def __init__(self, ui, path, rev=None):

        super(darcs_source, self).__init__(ui, path, rev=rev)

        if not os.path.exists(os.path.join(path, '_darcs', 'inventory')):

            raise NoRepo("couldn't open darcs repo %s" % path)

        if ElementTree is None:

            raise util.Abort(_("Python ElementTree module is not available"))

        self.path = os.path.realpath(path)

        self.lastrev = None

        self.changes = {}

        self.parents = {}

        self.tags = {}

    def before(self):

        self.tmppath = tempfile.mkdtemp(

            prefix='convert-' + os.path.basename(self.path) + '-')

        output, status = self.run('init', repodir=self.tmppath)

        self.checkexit(status)

        tree = self.xml('changes', '--xml-output', '--summary')

        tagname = None

        child = None

        for elt in tree.findall('patch'):

            node = elt.get('hash')

            name = elt.findtext('name', '')

            if name.startswith('TAG '):

                tagname = name[4:].strip()

            elif tagname is not None:

                self.tags[tagname] = node

                tagname = None

            self.changes[node] = elt

            self.parents[child] = [node]

            child = node

        self.parents[child] = []

    def after(self):

        self.ui.debug('cleaning up %s\n' % self.tmppath)

        shutil.rmtree(self.tmppath, ignore_errors=True)

    def _run(self, cmd, *args, **kwargs):

        cmdline = ['darcs', cmd, '--repodir', kwargs.get('repodir', self.path)]

        cmdline += args

        cmdline = [util.shellquote(arg) for arg in cmdline]

        cmdline += ['<', util.nulldev]

        cmdline = util.quotecommand(' '.join(cmdline))

        self.ui.debug(cmdline, '\n')

        return os.popen(cmdline, 'r')

    def run(self, cmd, *args, **kwargs):

        fp = self._run(cmd, *args, **kwargs)

        output = fp.read()

        return output, fp.close()

    def checkexit(self, status, output=''):

        if status:

            if output:

                self.ui.warn(_('darcs error:\n'))

                self.ui.warn(output)

            msg = util.explain_exit(status)[0]

            raise util.Abort(_('darcs %s') % msg)

    def xml(self, cmd, *opts):

        etree = ElementTree()

        fp = self._run(cmd, *opts)

        etree.parse(fp)

        self.checkexit(fp.close())

        return etree.getroot()

    def getheads(self):

        return self.parents[None]

    def getcommit(self, rev):

        elt = self.changes[rev]

        date = util.strdate(elt.get('local_date'), '%a %b %d %H:%M:%S %Z %Y')

        desc = elt.findtext('name') + '\n' + elt.findtext('comment', '')

        return commit(author=elt.get('author'), date=util.datestr(date),

                      desc=desc.strip(), parents=self.parents[rev])

    def pull(self, rev):

        output, status = self.run('pull', self.path, '--all',

                                  '--match', 'hash %s' % rev,

                                  '--no-test', '--no-posthook',

                                  '--external-merge', '/bin/false',

                                  repodir=self.tmppath)

        if status:

            if output.find('We have conflicts in') == -1:

                self.checkexit(status, output)

            output, status = self.run('revert', '--all', repodir=self.tmppath)

            self.checkexit(status, output)

    def getchanges(self, rev):

        self.pull(rev)

        copies = {}

        changes = []

        for elt in self.changes[rev].find('summary').getchildren():

            if elt.tag in ('add_directory', 'remove_directory'):

                continue

            if elt.tag == 'move':

                changes.append((elt.get('from'), rev))

                copies[elt.get('from')] = elt.get('to')

            else:

                changes.append((elt.text.strip(), rev))

        changes.sort()

        self.lastrev = rev

        return changes, copies

    def getfile(self, name, rev):

        if rev != self.lastrev:

            raise util.Abort(_('internal calling inconsistency'))

        return open(os.path.join(self.tmppath, name), 'rb').read()

    def getmode(self, name, rev):

        mode = os.lstat(os.path.join(self.tmppath, name)).st_mode

        return (mode & 0111) and 'x' or ''

    def gettags(self):

        return self.tags