#
# 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 os
import optparse
import platform
import re
import sys

from error import NoSuchProjectError
from error import InvalidProjectGroupsError

class Command(object):
  """Base class for any command line action in repo.
  """

  common = False
  manifest = None
  _optparse = None

  def WantPager(self, opt):
    return False

  @property
  def OptionParser(self):
    if self._optparse is None:
      try:
        me = 'repo %s' % self.NAME
        usage = self.helpUsage.strip().replace('%prog', me)
      except AttributeError:
        usage = 'repo %s' % self.NAME
      self._optparse = optparse.OptionParser(usage = usage)
      self._Options(self._optparse)
    return self._optparse

  def _Options(self, p):
    """Initialize the option parser.
    """

  def Usage(self):
    """Display usage and terminate.
    """
    self.OptionParser.print_usage()
    sys.exit(1)

  def Execute(self, opt, args):
    """Perform the action, after option parsing is complete.
    """
    raise NotImplementedError

  def _ResetPathToProjectMap(self, projects):
    self._by_path = dict((p.worktree, p) for p in projects)

  def _UpdatePathToProjectMap(self, project):
    self._by_path[project.worktree] = project

  def _GetProjectByPath(self, path):
    project = None
    if os.path.exists(path):
      oldpath = None
      while path \
        and path != oldpath \
        and path != self.manifest.topdir:
        try:
          project = self._by_path[path]
          break
        except KeyError:
          oldpath = path
          path = os.path.dirname(path)
    else:
      try:
        project = self._by_path[path]
      except KeyError:
        pass
    return project

  def GetProjects(self, args, missing_ok=False):
    """A list of projects that match the arguments.
    """
    all_projects = self.manifest.projects
    result = []

    mp = self.manifest.manifestProject

    groups = mp.config.GetString('manifest.groups')
    if not groups:
      groups = 'all,-notdefault,platform-' + platform.system().lower()
    groups = [x for x in re.split('[,\s]+', groups) if x]

    if not args:
      all_projects_list = all_projects.values()
      derived_projects = []
      for project in all_projects_list:
        if project.Registered:
          # Do not search registered subproject for derived projects
          # since its parent has been searched already
          continue
        derived_projects.extend(project.GetDerivedSubprojects())
      all_projects_list.extend(derived_projects)
      for project in all_projects_list:
        if ((missing_ok or project.Exists) and
            project.MatchesGroups(groups)):
          result.append(project)
    else:
      self._ResetPathToProjectMap(all_projects.values())

      for arg in args:
        project = all_projects.get(arg)

        if not project:
          path = os.path.abspath(arg).replace('\\', '/')
          project = self._GetProjectByPath(path)

          # If it's not a derived project, update path->project mapping and
          # search again, as arg might actually point to a derived subproject.
          if project and not project.Derived:
            search_again = False
            for subproject in project.GetDerivedSubprojects():
              self._UpdatePathToProjectMap(subproject)
              search_again = True
            if search_again:
              project = self._GetProjectByPath(path) or project

        if not project:
          raise NoSuchProjectError(arg)
        if not missing_ok and not project.Exists:
          raise NoSuchProjectError(arg)
        if not project.MatchesGroups(groups):
          raise InvalidProjectGroupsError(arg)

        result.append(project)

    def _getpath(x):
      return x.relpath
    result.sort(key=_getpath)
    return result

# pylint: disable-msg=W0223
# Pylint warns that the `InteractiveCommand` and `PagedCommand` classes do not
# override method `Execute` which is abstract in `Command`.  Since that method
# is always implemented in classes derived from `InteractiveCommand` and
# `PagedCommand`, this warning can be suppressed.
class InteractiveCommand(Command):
  """Command which requires user interaction on the tty and
     must not run within a pager, even if the user asks to.
  """
  def WantPager(self, opt):
    return False

class PagedCommand(Command):
  """Command which defaults to output in a pager, as its
     display tends to be larger than one screen full.
  """
  def WantPager(self, opt):
    return True

# pylint: enable-msg=W0223

class MirrorSafeCommand(object):
  """Command permits itself to run within a mirror,
     and does not require a working directory.
  """