#!/usr/bin/python

# Copyright 2014 Google Inc. All rights reserved.
#
# 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.

"""Sync files from/to an Android device."""

from __future__ import unicode_literals
import argparse
import glob
import locale
import os
import re
import stat
import subprocess
import sys
import time


def _sprintf(s, *args):
    # To be able to use string formatting, we first have to covert to
    # unicode strings; however, we must do so in a way that preserves all
    # bytes, and convert back at the end. An encoding that maps all byte
    # values to different Unicode codepoints is cp437.
    return (s.decode('cp437') % tuple([
        (x.decode('cp437') if type(x) == bytes else x) for x in args
    ])).encode('cp437')


def _print(s, *args):
    """Writes a binary string to stdout.

    Args:
      s: The binary format string to write.
      args: The args for the format string.
    """
    if hasattr(sys.stdout, 'buffer'):
        # Python 3.
        sys.stdout.buffer.write(_sprintf(s, *args) + b'\n')
        sys.stdout.buffer.flush()
    else:
        # Python 2.
        sys.stdout.write(_sprintf(s, *args) + b'\n')


class AdbFileSystem(object):
  """Mimics os's file interface but uses the adb utility."""

  def __init__(self, adb):
    self.stat_cache = {}
    self.adb = adb

  # Regarding parsing stat results, we only care for the following fields:
  # - st_size
  # - st_mtime
  # - st_mode (but only about S_ISDIR and S_ISREG properties)
  # Therefore, we only capture parts of 'ls -l' output that we actually use.
  # The other fields will be filled with dummy values.
  LS_TO_STAT_RE = re.compile(br'''^
                             (?:
                               (?P<S_IFREG> -) |
                               (?P<S_IFBLK> b) |
                               (?P<S_IFCHR> c) |
                               (?P<S_IFDIR> d) |
                               (?P<S_IFLNK> l) |
                               (?P<S_IFIFO> p) |
                               (?P<S_IFSOCK> s))
                             [-r][-w][-xsS]
                             [-r][-w][-xsS]
                             [-r][-w][-xtT]  # Mode string.
                             [ ]+
                             (?:
                                [0-9]+  # number of hard links
                                [ ]+
                                )?
                             [^ ]+  # User name/ID.
                             [ ]+
                             [^ ]+  # Group name/ID.
                             [ ]+
                             (?(S_IFBLK) [^ ]+[ ]+[^ ]+[ ]+)    # Device numbers.
                             (?(S_IFCHR) [^ ]+[ ]+[^ ]+[ ]+)    # Device numbers.
                             (?(S_IFDIR) [0-9]+ [ ]+)?          # directory Size.
                             (?(S_IFREG)
                               (?P<st_size> [0-9]+)             # Size.
                               [ ]+)
                             (?P<st_mtime>
                               [0-9]{4}-[0-9]{2}-[0-9]{2}       # Date.
                               [ ]
                               [0-9]{2}:[0-9]{2})               # Time.
                             [ ]
                             # Don't capture filename for symlinks (ambiguous).
                             (?(S_IFLNK) .* | (?P<filename> .*))
                             $''', re.DOTALL | re.VERBOSE)
  def LsToStat(self, line):
    """Convert a line from 'ls -l' output to a stat result.

    Args:
      line: Output line of 'ls -l' on Android.

    Returns:
      os.stat_result for the line.

    Raises:
      OSError: if the given string is not a 'ls -l' output line (but maybe an
      error message instead).
    """

    match = self.LS_TO_STAT_RE.match(line)
    if match is None:
      _print(b'Warning: could not parse %r.', line)
      raise OSError('Unparseable ls -al result.')
    groups = match.groupdict()

    # Get the values we're interested in.
    st_mode = (  # 0755
      stat.S_IRWXU | stat.S_IRGRP | stat.S_IXGRP | stat.S_IROTH | stat.S_IXOTH)
    if groups['S_IFREG']: st_mode |= stat.S_IFREG
    if groups['S_IFBLK']: st_mode |= stat.S_IFBLK
    if groups['S_IFCHR']: st_mode |= stat.S_IFCHR
    if groups['S_IFDIR']: st_mode |= stat.S_IFDIR
    if groups['S_IFIFO']: st_mode |= stat.S_IFIFO
    if groups['S_IFLNK']: st_mode |= stat.S_IFLNK
    if groups['S_IFSOCK']: st_mode |= stat.S_IFSOCK
    st_size = groups['st_size']
    if st_size is not None:
      st_size = int(st_size)
    st_mtime = time.mktime(time.strptime(match.group('st_mtime').decode('utf-8'),
                                         '%Y-%m-%d %H:%M'))

    # Fill the rest with dummy values.
    st_ino = 1
    st_rdev = 0
    st_nlink = 1
    st_uid = -2  # Nobody.
    st_gid = -2  # Nobody.
    st_atime = st_ctime = st_mtime

    stbuf = os.stat_result((st_mode, st_ino, st_rdev, st_nlink, st_uid, st_gid,
                            st_size, st_atime, st_mtime, st_ctime))
    filename = groups['filename']
    return stbuf, filename

  def Stdout(self, *popen_args):
    """Closes the process's stdout when done.

    Usage:
      with Stdout(...) as stdout:
        DoSomething(stdout)

    Args:
      popen_args: Arguments for subprocess.Popen; stdout=PIPE is implicitly
      added.

    Returns:
      An object for use by 'with'.
    """

    class Stdout(object):
      def __init__(self, popen):
        self.popen = popen

      def __enter__(self):
        return self.popen.stdout

      def __exit__(self, exc_type, exc_value, traceback):
        self.popen.stdout.close()
        if self.popen.wait() != 0:
          raise OSError('Subprocess exited with nonzero status.')
        return False

    return Stdout(subprocess.Popen(*popen_args, stdout=subprocess.PIPE))

  def QuoteArgument(self, arg):
    # Quotes an argument for use by adb shell.
    # Usually, arguments in 'adb shell' use are put in double quotes by adb,
    # but not in any way escaped.
    arg = arg.replace(b'\\', b'\\\\')
    arg = arg.replace(b'"', b'\\"')
    arg = arg.replace(b'$', b'\\$')
    arg = arg.replace(b'`', b'\\`')
    arg = b'"' + arg + b'"'
    return arg

  def IsWorking(self):
    """Tests the adb connection."""
    # This string should contain all possible evil, but no percent signs.
    # Note this code uses 'date' and not 'echo', as date just calls strftime
    # while echo does its own backslash escape handling additionally to the
    # shell's. Too bad printf "%s\n" is not available.
    test_strings = [
        b'(',
        b'(;  #`ls`$PATH\'"(\\\\\\\\){};!\xc0\xaf\xff\xc2\xbf'
    ]
    for test_string in test_strings:
      good = False
      with self.Stdout(self.adb + [b'shell', _sprintf(b'date +%s',
                                   self.QuoteArgument(test_string))]) as stdout:
        for line in stdout:
          line = line.rstrip(b'\r\n')
          if line == test_string:
            good = True
      if not good:
        return False
    return True

  def listdir(self, path):  # os's name, so pylint: disable=g-bad-name
    """List the contents of a directory, caching them for later lstat calls."""
    with self.Stdout(self.adb + [b'shell', _sprintf(b'ls -al %s',
                      self.QuoteArgument(path + b'/'))]) as stdout:
      for line in stdout:
        if line.startswith(b'total '):
            continue
        line = line.rstrip(b'\r\n')
        try:
          statdata, filename = self.LsToStat(line)
        except OSError:
          continue
        if filename is None:
          _print(b'Warning: could not parse %s', line)
        else:
          self.stat_cache[path + b'/' + filename] = statdata
          yield filename

  def lstat(self, path):  # os's name, so pylint: disable=g-bad-name
    """Stat a file."""
    if path in self.stat_cache:
      return self.stat_cache[path]
    with self.Stdout(self.adb + [b'shell', _sprintf(b'ls -ald %s',
                      self.QuoteArgument(path))]) as stdout:
      for line in stdout:
        if line.startswith(b'total '):
            continue
        line = line.rstrip(b'\r\n')
        statdata, filename = self.LsToStat(line)
        self.stat_cache[path] = statdata
        return statdata
    raise OSError('No such file or directory')

  def unlink(self, path):  # os's name, so pylint: disable=g-bad-name
    """Delete a file."""
    if subprocess.call(self.adb + [b'shell', _sprintf(b'rm %s',
                                   self.QuoteArgument(path))]) != 0:
      raise OSError('unlink failed')

  def rmdir(self, path):  # os's name, so pylint: disable=g-bad-name
    """Delete a directory."""
    if subprocess.call(self.adb + [b'shell', _sprintf(b'rmdir %s',
                                   self.QuoteArgument(path))]) != 0:
      raise OSError('rmdir failed')

  def makedirs(self, path):  # os's name, so pylint: disable=g-bad-name
    """Create a directory."""
    if subprocess.call(self.adb + [b'shell', _sprintf(b'mkdir -p %s',
                                   self.QuoteArgument(path))]) != 0:
      raise OSError('mkdir failed')

  def utime(self, path, times):
    # TODO(rpolzer): Find out why this does not work (returns status 255).
    """Set the time of a file to a specified unix time."""
    atime, mtime = times
    timestr = time.strftime(b'%Y%m%d.%H%M%S', time.localtime(mtime))
    if subprocess.call(self.adb + [b'shell', _sprintf(b'touch -mt %s %s',
                                   timestr, self.QuoteArgument(path))]) != 0:
      raise OSError('touch failed')
    timestr = time.strftime(b'%Y%m%d.%H%M%S', time.localtime(atime))
    if subprocess.call(self.adb + [b'shell',_sprintf( b'touch -at %s %s',
                                   timestr, self.QuoteArgument(path))]) != 0:
      raise OSError('touch failed')

  def glob(self, path):
    with self.Stdout(self.adb + [b'shell',
                                 _sprintf(b'for p in %s; do echo "$p"; done',
                                 path)]) as stdout:
      for line in stdout:
        yield line.rstrip(b'\r\n')

  def Push(self, src, dst):
    """Push a file from the local file system to the Android device."""
    if subprocess.call(self.adb + [b'push', src, dst]) != 0:
      raise OSError('push failed')

  def Pull(self, src, dst):
    """Pull a file from the Android device to the local file system."""
    if subprocess.call(self.adb + [b'pull', src, dst]) != 0:
      raise OSError('pull failed')


def BuildFileList(fs, path, prefix=b''):
  """Builds a file list.

  Args:
    fs: File system provider (can be os or AdbFileSystem()).
    path: Initial path.
    prefix: Path prefix for output file names.

  Yields:
    File names from path (prefixed by prefix).
    Directories are yielded before their contents.
  """
  try:
    statresult = fs.lstat(path)
  except OSError:
    return
  if stat.S_ISDIR(statresult.st_mode):
    yield prefix, statresult
    try:
      files = list(fs.listdir(path))
    except OSError:
      return
    files.sort()
    for n in files:
      if n == b'.' or n == b'..':
        continue
      for t in BuildFileList(fs, path + b'/' + n, prefix + b'/' + n):
        yield t
  elif stat.S_ISREG(statresult.st_mode) or stat.S_ISLNK(statresult.st_mode):
    yield prefix, statresult
  else:
    _print(b'Note: unsupported file: %s', path)


def DiffLists(a, b):
  """Compares two lists.

  Args:
    a: the first list.
    b: the second list.

  Returns:
    a_only: the items from list a.
    both: the items from both list, with the remaining tuple items combined.
    b_only: the items from list b.
  """
  a_only = []
  b_only = []
  both = []

  a_iter = iter(a)
  b_iter = iter(b)
  a_active = True
  b_active = True
  a_available = False
  b_available = False
  a_item = None
  b_item = None

  while a_active and b_active:
    if not a_available:
      try:
        a_item = next(a_iter)
        a_available = True
      except StopIteration:
        a_active = False
        break
    if not b_available:
      try:
        b_item = next(b_iter)
        b_available = True
      except StopIteration:
        b_active = False
        break
    if a_item[0] == b_item[0]:
      both.append(tuple([a_item[0]] + list(a_item[1:]) + list(b_item[1:])))
      a_available = False
      b_available = False
    elif a_item[0] < b_item[0]:
      a_only.append(a_item)
      a_available = False
    elif a_item[0] > b_item[0]:
      b_only.append(b_item)
      b_available = False
    else:
      raise

  if a_active:
    if a_available:
      a_only.append(a_item)
    for item in a_iter:
      a_only.append(item)
  if b_active:
    if b_available:
      b_only.append(b_item)
    for item in b_iter:
      b_only.append(item)

  return a_only, both, b_only


class FileSyncer(object):
  """File synchronizer."""

  def __init__(self, adb, local_path, remote_path, local_to_remote,
               remote_to_local, preserve_times, delete_missing, allow_overwrite,
               allow_replace, dry_run):
    self.local = local_path
    self.remote = remote_path
    self.adb = adb
    self.local_to_remote = local_to_remote
    self.remote_to_local = remote_to_local
    self.preserve_times = preserve_times
    self.delete_missing = delete_missing
    self.allow_overwrite = allow_overwrite
    self.allow_replace = allow_replace
    self.dry_run = dry_run
    self.local_only = None
    self.both = None
    self.remote_only = None
    self.num_bytes = 0
    self.start_time = time.time()

  def IsWorking(self):
    """Tests the adb connection."""
    return self.adb.IsWorking()

  def ScanAndDiff(self):
    """Scans the local and remote locations and identifies differences."""
    _print(b'Scanning and diffing...')
    locallist = BuildFileList(os, self.local)
    remotelist = BuildFileList(self.adb, self.remote)
    self.local_only, self.both, self.remote_only = DiffLists(locallist,
                                                             remotelist)
    if not self.local_only and not self.both and not self.remote_only:
      _print(b'No files seen. User error?')
    self.src_to_dst = (self.local_to_remote, self.remote_to_local)
    self.dst_to_src = (self.remote_to_local, self.local_to_remote)
    self.src_only = (self.local_only, self.remote_only)
    self.dst_only = (self.remote_only, self.local_only)
    self.src = (self.local, self.remote)
    self.dst = (self.remote, self.local)
    self.dst_fs = (self.adb, os)
    self.push = (b'Push', b'Pull')
    self.copy = (self.adb.Push, self.adb.Pull)

  def InterruptProtection(self, fs, name):
    """Sets up interrupt protection.

    Usage:
      with self.InterruptProtection(fs, name):
        DoSomething()

      If DoSomething() should get interrupted, the file 'name' will be deleted.
      The exception otherwise will be passed on.

    Args:
      fs: File system object.
      name: File name to delete.

    Returns:
      An object for use by 'with'.
    """

    dry_run = self.dry_run

    class DeleteInterruptedFile(object):
      def __enter__(self):
        pass

      def __exit__(self, exc_type, exc_value, traceback):
        if exc_type is not None:
          _print(b'Interrupted-%s-Delete: %s',
                 b'Pull' if fs == os else b'Push', name)
          if not dry_run:
            fs.unlink(name)
        return False

    return DeleteInterruptedFile()

  def PerformDeletions(self):
    """Perform all deleting necessary for the file sync operation."""
    if not self.delete_missing:
      return
    for i in [0, 1]:
      if self.src_to_dst[i] and not self.dst_to_src[i]:
        if not self.src_only[i] and not self.both:
          _print(b'Cowardly refusing to delete everything.')
        else:
          for name, s in reversed(self.dst_only[i]):
            dst_name = self.dst[i] + name
            _print(b'%s-Delete: %s', self.push[i], dst_name)
            if stat.S_ISDIR(s.st_mode):
              if not self.dry_run:
                self.dst_fs[i].rmdir(dst_name)
            else:
              if not self.dry_run:
                self.dst_fs[i].unlink(dst_name)
          del self.dst_only[i][:]

  def PerformOverwrites(self):
    """Delete files/directories that are in the way for overwriting."""
    src_only_prepend = ([], [])
    for name, localstat, remotestat in self.both:
      if stat.S_ISDIR(localstat.st_mode) and stat.S_ISDIR(remotestat.st_mode):
        # A dir is a dir is a dir.
        continue
      elif stat.S_ISDIR(localstat.st_mode) or stat.S_ISDIR(remotestat.st_mode):
        # Dir vs file? Nothing to do here yet.
        pass
      else:
        # File vs file? Compare sizes.
        if localstat.st_size == remotestat.st_size:
          continue
      l2r = self.local_to_remote
      r2l = self.remote_to_local
      if l2r and r2l:
        # Truncate times to full minutes, as Android's "ls" only outputs minute
        # accuracy.
        localminute = int(localstat.st_mtime / 60)
        remoteminute = int(remotestat.st_mtime / 60)
        if localminute > remoteminute:
          r2l = False
        elif localminute < remoteminute:
          l2r = False
      if l2r and r2l:
        _print(b'Unresolvable: %s', name)
        continue
      if l2r:
        i = 0  # Local to remote operation.
        src_stat = localstat
        dst_stat = remotestat
      else:
        i = 1  # Remote to local operation.
        src_stat = remotestat
        dst_stat = localstat
      dst_name = self.dst[i] + name
      _print(b'%s-Delete-Conflicting: %s', self.push[i], dst_name)
      if stat.S_ISDIR(localstat.st_mode) or stat.S_ISDIR(remotestat.st_mode):
        if not self.allow_replace:
          _print(b'Would have to replace to do this. '
                 b'Use --force to allow this.')
          continue
      if not self.allow_overwrite:
        _print(b'Would have to overwrite to do this, '
               b'which --no-clobber forbids.')
        continue
      if stat.S_ISDIR(dst_stat.st_mode):
        kill_files = [x for x in self.dst_only[i]
                      if x[0][:len(name) + 1] == name + b'/']
        self.dst_only[i][:] = [x for x in self.dst_only[i]
                               if x[0][:len(name) + 1] != name + b'/']
        for l, s in reversed(kill_files):
          if stat.S_ISDIR(s.st_mode):
            if not self.dry_run:
              self.dst_fs[i].rmdir(self.dst[i] + l)
          else:
            if not self.dry_run:
              self.dst_fs[i].unlink(self.dst[i] + l)
        if not self.dry_run:
          self.dst_fs[i].rmdir(dst_name)
      elif stat.S_ISDIR(src_stat.st_mode):
        if not self.dry_run:
          self.dst_fs[i].unlink(dst_name)
      else:
        if not self.dry_run:
          self.dst_fs[i].unlink(dst_name)
      src_only_prepend[i].append((name, src_stat))
    for i in [0, 1]:
      self.src_only[i][:0] = src_only_prepend[i]

  def PerformCopies(self):
    """Perform all copying necessary for the file sync operation."""
    for i in [0, 1]:
      if self.src_to_dst[i]:
        for name, s in self.src_only[i]:
          src_name = self.src[i] + name
          dst_name = self.dst[i] + name
          _print(b'%s: %s', self.push[i], dst_name)
          if stat.S_ISDIR(s.st_mode):
            if not self.dry_run:
              self.dst_fs[i].makedirs(dst_name)
          else:
            with self.InterruptProtection(self.dst_fs[i], dst_name):
              if not self.dry_run:
                self.copy[i](src_name, dst_name)
              self.num_bytes += s.st_size
          if not self.dry_run:
            if self.preserve_times:
              _print(b'%s-Times: accessed %s, modified %s',
                     self.push[i],
                     time.asctime(time.localtime(s.st_atime)).encode('utf-8'),
                     time.asctime(time.localtime(s.st_mtime)).encode('utf-8'))
              self.dst_fs[i].utime(dst_name, (s.st_atime, s.st_mtime))

  def TimeReport(self):
    """Report time and amount of data transferred."""
    if self.dry_run:
      _print(b'Total: %d bytes', self.num_bytes)
    else:
      end_time = time.time()
      dt = end_time - self.start_time
      rate = self.num_bytes / 1024.0 / dt
      _print(b'Total: %d KB/s (%d bytes in %.3fs)', rate, self.num_bytes, dt)


def ExpandWildcards(globber, path):
  if path.find(b'?') == -1 and path.find(b'*') == -1 and path.find(b'[') == -1:
    return [path]
  return globber.glob(path)


def FixPath(src, dst):
  # rsync-like path munging to make remote specifications shorter.
  append = b''
  pos = src.rfind(b'/')
  if pos >= 0:
    if src.endswith(b'/'):
      # Final slash: copy to the destination "as is".
      src = src[:-1]
    else:
      # No final slash: destination name == source name.
      append = src[pos:]
  else:
    # No slash at all - use same name at destination.
    append = b'/' + src
  # Append the destination file name if any.
  # BUT: do not append "." or ".." components!
  if append != b'/.' and append != b'/..':
    dst += append
  return (src, dst)


def main(*args):
  parser = argparse.ArgumentParser(
      description='Synchronize a directory between an Android device and the '+
      'local file system')
  parser.add_argument('source', metavar='SRC', type=str, nargs='+',
                      help='The directory to read files/directories from. '+
                      'This must be a local path if -R is not specified, '+
                      'and an Android path if -R is specified. If SRC does '+
                      'not end with a final slash, its last path component '+
                      'is appended to DST (like rsync does).')
  parser.add_argument('destination', metavar='DST', type=str,
                      help='The directory to write files/directories to. '+
                      'This must be an Android path if -R is not specified, '+
                      'and a local path if -R is specified.')
  parser.add_argument('-e', '--adb', metavar='COMMAND', default='adb', type=str,
                      help='Use the given adb binary and arguments.')
  parser.add_argument('--device', action='store_true',
                      help='Directs command to the only connected USB device; '+
                      'returns an error if more than one USB device is '+
                      'present. '+
                      'Corresponds to the "-d" option of adb.')
  parser.add_argument('--emulator', action='store_true',
                      help='Directs command to the only running emulator; '+
                      'returns an error if more than one emulator is running. '+
                      'Corresponds to the "-e" option of adb.')
  parser.add_argument('-s', '--serial', metavar='DEVICE', type=str,
                      help='Directs command to the device or emulator with '+
                      'the given serial number or qualifier. Overrides '+
                      'ANDROID_SERIAL environment variable. Use "adb devices" '+
                      'to list all connected devices with their respective '+
                      'serial number. '+
                      'Corresponds to the "-s" option of adb.')
  parser.add_argument('-H', '--host', metavar='HOST', type=str,
                      help='Name of adb server host (default: localhost). '+
                      'Corresponds to the "-H" option of adb.')
  parser.add_argument('-P', '--port', metavar='PORT', type=str,
                      help='Port of adb server (default: 5037). '+
                      'Corresponds to the "-P" option of adb.')
  parser.add_argument('-R', '--reverse', action='store_true',
                      help='Reverse sync (pull, not push).')
  parser.add_argument('-2', '--two-way', action='store_true',
                      help='Two-way sync (compare modification time; after '+
                      'the sync, both sides will have all files in the '+
                      'respective newest version. This relies on the clocks '+
                      'of your system and the device to match.')
  #parser.add_argument('-t', '--times', action='store_true',
  #                    help='Preserve modification times when copying.')
  parser.add_argument('-d', '--delete', action='store_true',
                      help='Delete files from DST that are not present on '+
                      'SRC. Mutually exclusive with -2.')
  parser.add_argument('-f', '--force', action='store_true',
                      help='Allow deleting files/directories when having to '+
                      'replace a file by a directory or vice versa. This is '+
                      'disabled by default to prevent large scale accidents.')
  parser.add_argument('-n', '--no-clobber', action='store_true',
                      help='Do not ever overwrite any '+
                      'existing files. Mutually exclusive with -f.')
  parser.add_argument('--dry-run',action='store_true',
                      help='Do not do anything - just show what would '+
                      'be done.')
  args = parser.parse_args()
  args_encoding = locale.getdefaultlocale()[1]

  localpatterns = [x.encode(args_encoding) for x in args.source]
  remotepath = args.destination.encode(args_encoding)
  adb = args.adb.encode(args_encoding).split(b' ')
  if args.device:
    adb += [b'-d']
  if args.emulator:
    adb += [b'-e']
  if args.serial != None:
    adb += [b'-s', args.serial.encode(args_encoding)]
  if args.host != None:
    adb += [b'-H', args.host.encode(args_encoding)]
  if args.port != None:
    adb += [b'-P', args.port.encode(args_encoding)]
  adb = AdbFileSystem(adb)

  # Expand wildcards.
  localpaths = []
  remotepaths = []
  if args.reverse:
    for pattern in localpatterns:
      for src in ExpandWildcards(adb, pattern):
        src, dst = FixPath(src, remotepath)
        localpaths.append(src)
        remotepaths.append(dst)
  else:
    for src in localpatterns:
      src, dst = FixPath(src, remotepath)
      localpaths.append(src)
      remotepaths.append(dst)

  preserve_times = False  # args.times
  delete_missing = args.delete
  allow_replace = args.force
  allow_overwrite = not args.no_clobber
  dry_run = args.dry_run
  local_to_remote = True
  remote_to_local = False
  if args.two_way:
    local_to_remote = True
    remote_to_local = True
  if args.reverse:
    local_to_remote, remote_to_local = remote_to_local, local_to_remote
    localpaths, remotepaths = remotepaths, localpaths
  if allow_replace and not allow_overwrite:
    _print(b'--no-clobber and --force are mutually exclusive.')
    parser.print_help()
    return
  if delete_missing and local_to_remote and remote_to_local:
    _print(b'--delete and --two-way are mutually exclusive.')
    parser.print_help()
    return

  # Two-way sync is only allowed with disjoint remote and local path sets.
  if (remote_to_local and local_to_remote) or delete_missing:
    if ((remote_to_local and len(localpaths) != len(set(localpaths))) or
        (local_to_remote and len(remotepaths) != len(set(remotepaths)))):
      _print(b'--two-way and --delete are only supported for disjoint sets of '
             b'source and destination paths (in other words, all SRC must '
             b'differ in basename).')
      parser.print_help()
      return

  for i in range(len(localpaths)):
    _print(b'Sync: local %s, remote %s', localpaths[i], remotepaths[i])
    syncer = FileSyncer(adb, localpaths[i], remotepaths[i],
                        local_to_remote, remote_to_local, preserve_times,
                        delete_missing, allow_overwrite, allow_replace, dry_run)
    if not syncer.IsWorking():
      _print(b'Device not connected or not working.')
      return
    try:
      syncer.ScanAndDiff()
      syncer.PerformDeletions()
      syncer.PerformOverwrites()
      syncer.PerformCopies()
    finally:
      syncer.TimeReport()

if __name__ == '__main__':
  main(*sys.argv)
