#
# Copyright (C) 2008 The Android Open Source Project
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#      http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.


import re
import sys

from command import Command

CHANGE_RE = re.compile(r'^([1-9][0-9]*)(?:[/\.-]([1-9][0-9]*))?$')


class Download(Command):
    common = True
    helpSummary = "Download and checkout a change"
    helpUsage = """
%prog {project change[/patchset]}...
"""
    helpDescription = """
The '%prog' command downloads a change from the review system and
makes it available in your project's local working directory.
"""

    def _Options(self, p):
        p.add_option('-c', '--cherry-pick',
                     dest='cherrypick', action='store_true',
                     help="cherry-pick instead of checkout")
        p.add_option('-r', '--revert',
                     dest='revert', action='store_true',
                     help="revert instead of checkout")
        p.add_option('-f', '--ff-only',
                     dest='ffonly', action='store_true',
                     help="force fast-forward merge")

    def _ParseChangeIds(self, args):
        if not args:
            self.Usage()

        to_get = []
        project = None

        for a in args:
            m = CHANGE_RE.match(a)
            if m:
                if not project:
                    self.Usage()
                chg_id = int(m.group(1))
                if m.group(2):
                    ps_id = int(m.group(2))
                else:
                    ps_id = 1
                to_get.append((project, chg_id, ps_id))
            else:
                project = self.GetProjects([a])[0]
        return to_get

    def Execute(self, opt, args):
        for project, change_id, ps_id in self._ParseChangeIds(args):
            dl = project.DownloadPatchSet(change_id, ps_id)
            if not dl:
                print('[%s] change %d/%d not found'
                      % (project.name, change_id, ps_id),
                      file=sys.stderr)
                sys.exit(1)

            if not opt.revert and not dl.commits:
                print('[%s] change %d/%d has already been merged'
                      % (project.name, change_id, ps_id),
                      file=sys.stderr)
                continue

            if len(dl.commits) > 1:
                print('[%s] %d/%d depends on %d unmerged changes:' \
                      % (project.name, change_id, ps_id, len(dl.commits)),
                      file=sys.stderr)
                for c in dl.commits:
                    print('  %s' % (c), file=sys.stderr)
            if opt.cherrypick:
                project._CherryPick(dl.commit)
            elif opt.revert:
                project._Revert(dl.commit)
            elif opt.ffonly:
                project._FastForward(dl.commit, ffonly=True)
            else:
                project._Checkout(dl.commit)
