#!/usr/bin/env python

import atexit
import contextlib
import errno
import shutil
import subprocess
import sys
import tarfile
import tempfile
import urllib2
import os
import zipfile


def tempdir(prefix=''):
  directory = tempfile.mkdtemp(prefix=prefix)
  atexit.register(shutil.rmtree, directory)
  return directory


@contextlib.contextmanager
def scoped_cwd(path):
  cwd = os.getcwd()
  os.chdir(path)
  try:
    yield
  finally:
    os.chdir(cwd)


def download(text, url, path):
  safe_mkdir(os.path.dirname(path))
  with open(path, 'w') as local_file:
    web_file = urllib2.urlopen(url)
    file_size = int(web_file.info().getheaders("Content-Length")[0])
    downloaded_size = 0
    block_size = 128

    ci = os.environ.get('CI') == '1'

    while True:
      buf = web_file.read(block_size)
      if not buf:
        break

      downloaded_size += len(buf)
      local_file.write(buf)

      if not ci:
        percent = downloaded_size * 100. / file_size
        status = "\r%s  %10d  [%3.1f%%]" % (text, downloaded_size, percent)
        print status,

    if ci:
      print "%s done." % (text)
    else:
      print
  return path


def extract_tarball(tarball_path, member, destination):
  with tarfile.open(tarball_path) as tarball:
    tarball.extract(member, destination)


def extract_zip(zip_path, destination):
  if sys.platform == 'darwin':
    # Use unzip command on Mac to keep symbol links in zip file work.
    execute(['unzip', zip_path, '-d', destination])
  else:
    with zipfile.ZipFile(zip_path) as z:
      z.extractall(destination)

def make_zip(zip_file_path, files, dirs):
  safe_unlink(zip_file_path)
  if sys.platform == 'darwin':
    files += dirs
    execute(['zip', '-r', '-y', zip_file_path] + files)
  else:
    zip_file = zipfile.ZipFile(zip_file_path, "w", zipfile.ZIP_DEFLATED)
    for filename in files:
      zip_file.write(filename, filename)
    for dirname in dirs:
      for root, _, filenames in os.walk(dirname):
        for f in filenames:
          zip_file.write(os.path.join(root, f))
    zip_file.close()


def rm_rf(path):
  try:
    shutil.rmtree(path)
  except OSError as e:
    if e.errno != errno.ENOENT:
      raise


def safe_unlink(path):
  try:
    os.unlink(path)
  except OSError as e:
    if e.errno != errno.ENOENT:
      raise


def safe_mkdir(path):
  try:
    os.makedirs(path)
  except OSError as e:
    if e.errno != errno.EEXIST:
      raise


def execute(argv):
  try:
    return subprocess.check_output(argv, stderr=subprocess.STDOUT)
  except subprocess.CalledProcessError as e:
    print e.output
    raise e


def get_atom_shell_version():
  return subprocess.check_output(['git', 'describe', '--tags']).strip()


def s3_config():
  config = (os.environ.get('ATOM_SHELL_S3_BUCKET', ''),
            os.environ.get('ATOM_SHELL_S3_ACCESS_KEY', ''),
            os.environ.get('ATOM_SHELL_S3_SECRET_KEY', ''))
  message = ('Error: Please set the $ATOM_SHELL_S3_BUCKET, '
             '$ATOM_SHELL_S3_ACCESS_KEY, and '
             '$ATOM_SHELL_S3_SECRET_KEY environment variables')
  assert all(len(c) for c in config), message
  return config


def s3put(bucket, access_key, secret_key, prefix, key_prefix, files):
  args = [
    's3put',
    '--bucket', bucket,
    '--access_key', access_key,
    '--secret_key', secret_key,
    '--prefix', prefix,
    '--key_prefix', key_prefix,
    '--grant', 'public-read'
  ] + files

  execute(args)