#!/usr/bin/python
##############################################################################
# Copyright (c) 2018 AT&T Intellectual Property. 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.                                             #
##############################################################################

#
#  jcopy.py - Copy a file or files to a target directory, making
#    substitutions as needed from the values contained in a YAML file.
#
#  usage: jcopy.py <yaml> <in_dir_or_file> <out_dir>
#
#  Note: jcopy.sh is for Python2, jcopy3.sh is for Python3
#

import os.path
import jinja2
import sys
import yaml

def expand_files(target_dir, dir_name, files):
  global total
  xlen = len(sys.argv[2])
  targdir = target_dir + dir_name[xlen:]
  if not os.path.exists(targdir):
    os.makedirs(targdir)
  env = jinja2.Environment()
  env.trim_blocks = True
  env.lstrip_blocks = True

  for f in files:
    if f.endswith(".j2"):
      t = f.replace(".j2", ".yaml")
      source_path = dir_name + '/' + f
      target_path = targdir + '/' + t
      if os.path.isfile(source_path):
        with open(source_path) as fd:
          template = env.from_string(fd.read())
        data = template.render(yaml=yaml)
        fd2 = open(target_path,'w')
        fd2.write(data)
        fd2.write("\n")
        fd2.close()
        print '{0} -> {1}'.format(source_path, target_path)
        total += 1

def expand_file(target_file, file):
  global total
  if not os.path.exists(os.path.dirname(target_file)):
    os.makedirs(os.path.dirname(target_file))
  env = jinja2.Environment()
  env.trim_blocks = True
  env.lstrip_blocks = True
  with open(file) as fd:
    template = env.from_string(fd.read())
  data = template.render(yaml=yaml)
  fd2 = open(target_file,'w')
  fd2.write(data)
  fd2.write("\n")
  fd2.close()
  print '{0} -> {1}'.format(file, target_file)
  total += 1

if len(sys.argv) != 4:
  print 'usage: jcopy.py <yaml> <in_dir_or_file> <out_dir>'
  sys.exit(1)

with open(sys.argv[1]) as f:
  yaml = yaml.safe_load(f)

total = 0
if os.path.isfile(sys.argv[2]):
  expand_file(sys.argv[3], sys.argv[2])
else:
  os.path.walk(sys.argv[2], expand_files, sys.argv[3])
print '%d files processed.' % total
sys.exit(0)

# sudo python -m ensurepip --default-pip
# sudo python -m pip install --upgrade pip setuptools wheel
# pip install --user jinja2 PyYAML