#!/usr/bin/env python
# 
# Attribution Notice
# ------------------
# This file uses parts of Node.js `configure`.
# Please refer to https://github.com/joyent/node.
#
import optparse
import os
import pprint
import re
import shlex
import subprocess
import sys
import platform

CC = os.environ.get('CC', 'cc')

root_dir = os.path.dirname(__file__)
build_dir = './build'

# Parse options
parser = optparse.OptionParser()
parser.add_option("--debug",
    action="store_true",
    dest="debug",
    help="Also build the debug build.")

parser.add_option("--dest-cpu",
    action="store",
    dest="dest_cpu",
    help="CPU architecture to build for. Valid values are: ia32, x64.")

parser.add_option("--shared",
    action="store_true",
    dest="shared",
    help="Build and use shared libsnowcrash instead of static one.")

parser.add_option("--include-integration-tests",
    action="store_true",
    dest="include_integration_tests",
    help="Configure for integration testing using Cucumber")

(options, args) = parser.parse_args()

def write(filename, data):
  filename = os.path.join(root_dir, filename)
  print "creating ", filename
  f = open(filename, 'w+')
  f.write(data)

def cc_macros():
  """Checks predefined macros using the CC command."""

  try:
    p = subprocess.Popen(shlex.split(CC) + ['-dM', '-E', '-'],
                         stdin=subprocess.PIPE,
                         stdout=subprocess.PIPE,
                         stderr=subprocess.PIPE)
  except OSError:
    print '''Configure error: No acceptable C compiler found!

        Please make sure you have a C compiler installed on your system and/or
        consider adjusting the CC environment variable if you installed
        it in a non-standard prefix.
        '''
    sys.exit()

  p.stdin.write('\n')
  out = p.communicate()[0]

  out = str(out).split('\n')

  k = {}
  for line in out:
    lst = shlex.split(line)
    if len(lst) > 2:
      key = lst[1]
      val = lst[2]
      k[key] = val
  return k

def host_arch_cc():
  """Host architecture check using the CC command."""

  k = cc_macros()

  matchup = {
    '__x86_64__'  : 'x64',
    '__i386__'    : 'ia32',
    '__arm__'     : 'arm',
  }

  rtn = 'ia32' # default

  for i in matchup:
    if i in k and k[i] != '0':
      rtn = matchup[i]
      break

  return rtn

def host_arch_win():
  """Host architecture check using environ vars (better way to do this?)"""

  arch = os.environ.get('PROCESSOR_ARCHITECTURE', 'x86')

  matchup = {
    'AMD64'  : 'x64',
    'x86'    : 'ia32',
    'arm'    : 'arm',
  }

  return matchup.get(arch, 'ia32')  

def configure_snowcrash(o):
  # Build configuration
  o['default_configuration'] = 'Debug' if options.debug else 'Release'

  # Architecture
  host_arch = host_arch_win() if os.name == 'nt' else host_arch_cc()
  target_arch = options.dest_cpu or host_arch
  o['variables']['host_arch'] = host_arch
  o['variables']['target_arch'] = target_arch
  o['variables']['libsnowcrash_type'] = 'shared_library' if options.shared else 'static_library'

#
# Cucumber testing environment
#
# TODO: use bundle check
if options.include_integration_tests:
    print "Installing dependencies for integration tests..."
    try:
        if sys.platform == 'win32':
            subprocess.call(["bundle.bat", "install"])
        else:
            subprocess.call(["bundle", "install"])
    except OSError as e:
        if e.errno == os.errno.ENOENT:
            raise RuntimeError(
                "Integration test dependecies rely on Ruby Bundler "
                "but it cannot be find in the system $PATH. "
                "Please make sure to install Bundler or/and to "
                "add it to the $PATH."
            )
        else:
            raise

#
# config.gypi
#
output = {
  'variables': { 'python': sys.executable },
  'include_dirs': [],
  'libraries': [],
  'defines': [],
  'cflags': [],
}

configure_snowcrash(output)

# variables should be a root level element,
# move everything else to target_defaults
variables = output['variables']
del output['variables']
output = {
  'variables': variables,
  'target_defaults': output
}

write('config.gypi', "# Do not edit. Generated by the configure script.\n" +
  pprint.pformat(output, indent=2) + "\n")

#
# config.mk
# 
config = {
  'BUILDTYPE': 'Debug' if options.debug else 'Release',
  'PYTHON': sys.executable,
  'BUILD_DIR': build_dir,
  'INTEGRATION_TESTS': '1' if options.include_integration_tests else ''
}
config = '\n'.join(map('='.join, config.iteritems())) + '\n'

write('config.mk',
      '# Do not edit. Generated by the configure script.\n' + config)

#
# Gyp call
#
print "creating makefiles"

gyp_args = ['--generator-output', build_dir, '--depth', '.']
if sys.platform == 'win32':
  # Windows
  gyp_args.extend(['-f', 'msvs'])
else:
  # Posix systems
  gyp_args.extend(['-f', 'make'])

# Include common.gypi and config.gypi 
if sys.platform == 'win32':
  options_fn = os.path.join(root_dir, 'config.gypi')
else:
  options_fn = os.path.join(os.path.abspath(root_dir), 'config.gypi')

if os.path.exists(options_fn):
  gyp_args.extend(['-I', options_fn])

subprocess.call([sys.executable, 'tools/gyp/gyp_main.py'] + gyp_args)

# All done
print "All OK."