#!/usr/bin/env python
# Copyright 2015 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.

'''Bundles the Blimp Engine and its runtime dependencies into a tarball.

   The created bundle can be passed as input to docker build.  E.g.
   docker build - < ../../out-linux/Debug/blimp_engine_deps.tar
'''


import argparse
import errno
import os
import subprocess
import sys
import tarfile

def ReadDependencies(manifest):
  """Read the manifest and return the list of dependencies.
  :raises IOError: if the manifest could not be read.
  """
  deps = []
  with open(manifest) as f:
    for line in f.readlines():
      # Strip comments.
      dep = line.partition('#')[0].strip()
      # Ignore empty strings.
      if dep:
        deps.append(dep)
  return deps

def main():
  parser = argparse.ArgumentParser(description=__doc__)
  parser.add_argument('--build-dir',
                      help=('build output directory (e.g. out/Debug)'),
                      required=True,
                      metavar='DIR')
  parser.add_argument('--dockerfile',
                      help=('Dockerfile to add to the bundle'),
                      required=True,
                      metavar='FILE')
  parser.add_argument('--startup-script',
                      help=('Engine startup script to add to the bundle'),
                      required=True,
                      metavar='FILE')
  parser.add_argument('--manifest',
                      help=('engine manifest'),
                      required=True)
  parser.add_argument('--output',
                      help=('name and path of bundle to create'),
                      required=True,
                      metavar='FILE')
  args = parser.parse_args()

  deps = ReadDependencies(args.manifest)

  # Add the deps to the tarball along with the Dockerfile.
  with tarfile.open(args.output, 'w') as tarball:
    tarball.add(args.dockerfile, arcname='Dockerfile')
    tarball.add(args.startup_script, arcname='start_engine.sh')
    os.chdir(args.build_dir)
    for dep in deps:
      try:
        tarball.add(dep)
      except OSError as e:
        if e.errno == errno.ENOENT:
          print >> sys.stderr, dep + " not found (did you build the engine?)"
          exit(1)

if __name__ == "__main__":
  main()