#!/usr/bin/env python
# Copyright (c) 2011 The Chromium Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.

"""Display active git branches and code changes in a ChromiumOS workspace."""

import optparse
import os
import re
import subprocess

def RunCommand(path, command):
  """Run a command in a given directory, return stdout."""

  return subprocess.Popen(command,
                          cwd=path,
                          stdout=subprocess.PIPE).communicate()[0].rstrip()

#
# Taken with slight modification from gclient_utils.py in the depot_tools
# project.
#
def FindFileUpwards(filename, path):
  """Search upwards from the a directory to find a file."""

  path = os.path.realpath(path)
  while True:
    file_path = os.path.join(path, filename)
    if os.path.exists(file_path):
      return file_path
    (new_path, _) = os.path.split(path)
    if new_path == path:
      return None
    path = new_path


def ShowName(relative_name, color):
  """Display the directory name."""

  if color:
    print('\033[44m\033[37m%s\033[0m' % relative_name)
  else:
    print relative_name


def GetBranches(full_name, relative_name, color):
  """Return a list of branch descriptions."""

  command = ['git', 'branch', '-vv']

  if color:
    command.append('--color')

  branches = RunCommand(full_name, command).splitlines()

  if re.search(r"\(no branch\)", branches[0]):
    return []

  return branches

def GetStatus(full_name, relative_name, color):
  """Return a list of files that have modifications."""

  command = ['git', 'status', '-s']

  return RunCommand(full_name, command).splitlines()


def GetHistory(full_name, relative_name, color, author, days):
  """Return a list of oneline log messages.

  The messages are for the author going back a specified number of days.
  """

  command = ['git', 'log',
             '--author=' + author,
             '--after=' + '-' + str(days) + 'days',
             '--pretty=oneline',
             'm/master']

  return RunCommand(full_name, command).splitlines()


def ShowDir(full_name, relative_name, color, logs, author, days):
  """Display active work in a single git repository."""

  branches = GetBranches(full_name, relative_name, color)
  status = GetStatus(full_name, relative_name, color)

  if logs:
    history = GetHistory(full_name, relative_name, color, author, days)
  else:
    history = []

  if branches or status or history:
    ShowName(relative_name, color)

  if branches: print '\n'.join(branches)
  if status: print '\n'.join(status)
  if history: print '\n'.join(history)

  if branches or status or history:
    print ""


def FindRoot():
  """Returns the repo root."""

  repo_file = '.repo'
  repo_path = FindFileUpwards(repo_file, os.getcwd())

  if repo_path is None:
    raise Exception('Failed to find %s.' % repo_file)

  return os.path.dirname(repo_path)


def main():
  parser = optparse.OptionParser(usage = 'usage: %prog [options]\n')

  parser.add_option('-l', '--logs', default=False,
                    help='Show the last few days of your commits in short '
                         'form.',
                    action='store_true',
                    dest='logs')

  parser.add_option('-d', '--days', default=8,
                    help='Set the number of days of history to show.',
                    type='int',
                    dest='days')

  parser.add_option('-a', '--author', default=os.environ['USER'],
                    help='Set the author to filter for.',
                    type='string',
                    dest='author')

  options, arguments = parser.parse_args()

  if arguments:
    parser.print_usage()
    return 1

  color = os.isatty(1)
  root = FindRoot()
  repos = RunCommand(root, ['repo', 'forall', '-c', 'pwd']).splitlines()

  # We want to use the full path for testing, but we want to use the relative
  # path for display.
  reldirs = [re.sub('^' + re.escape(root) + '/', '', p) for p in repos]

  for full, relative in zip(repos, reldirs):
    ShowDir(full, relative, color, options.logs, options.author, options.days)


if __name__ == '__main__':
  main()