import re

import subprocess

from reviewboard.diffviewer.parser import DiffParser

from reviewboard.scmtools.core import FileNotFoundError, SCMError, \

                                      SCMTool

class MonotoneTool(SCMTool):

    def __init__(self, repository):

        SCMTool.__init__(self, repository)

        self.client = MonotoneClient(repository.path)

    def get_file(self, path, revision=None):

        # revision is actually the file id here...

        if not revision:

            return ""

        return self.client.get_file(revision)

    def file_exists(self, path, revision=None):

        # revision is actually the file id here...

        if not revision:

            return False

        try:

            self.client.get_file(revision)

        except FileNotFoundError:

            return False

        return True

    def parse_diff_revision(self, file_str, revision_str):

        return file_str, revision_str

    def get_diffs_use_absolute_paths(self):

        return True

    def get_fields(self):

        return ['diff_path']

    def get_parser(self, data):

        return MonotoneDiffParser(data)

class MonotoneDiffParser(DiffParser):

    INDEX_SEP = "=" * 60

    def parse_special_header(self, linenum, info):

        if self.lines[linenum].startswith("#"):

            if "is binary" in self.lines[linenum]:

                info['binary'] = True

                linenum += 1

            elif self.lines[linenum + 1] == self.INDEX_SEP:

                # this is a standard mtn diff header (comments with the file summary)

                linenum += 1

        return linenum

class MonotoneClient:

    def __init__(self, path):

        self.path = path

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

            raise ImportError

    def get_file(self, fileid):

        args = ['mtn', '-d', self.path, 'automate', 'get_file', fileid]

        p = subprocess.Popen(args, stderr=subprocess.PIPE, stdout=subprocess.PIPE, close_fds=True)

        out = p.stdout.read()

        err = p.stderr.read()

        status = p.wait()

        if status:

            if "mtn: misuse: no file" in err >= 0:

                raise FileNotFoundError

            else:

                raise SCMError(err)

        return out