# -*- coding: utf-8 -*-

import os
import subprocess
import re


def LoadSystemIncludes( filetype ):
    regex = re.compile(r'(?:\#include \<...\> search starts here\:)(?P<list>.*?)(?:End of search list)', re.DOTALL)
    process = subprocess.Popen(['clang', '-v', '-E', '-x', filetype, '-'], stdin=subprocess.PIPE, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
    process_out, process_err = process.communicate('')
    output = process_out + process_err
    includes = []
    for p in re.search(regex, output.decode('utf-8')).group('list').split('\n'):
        p = p.strip()
        if len(p) > 0 and p.find('(framework directory)') < 0:
            includes.append('-isystem')
            includes.append(p)
    return includes


def DirectoryOfThisScript():
  return os.path.dirname( os.path.abspath( __file__ ) )


def MakeRelativePathsInFlagsAbsolute( flags, working_directory ):
  if not working_directory:
    return list( flags )
  new_flags = []
  make_next_absolute = False
  path_flags = [ '-isystem', '-I', '-iquote', '--sysroot=' ]
  for flag in flags:
    new_flag = flag

    if make_next_absolute:
      make_next_absolute = False
      if not flag.startswith( '/' ):
        new_flag = os.path.join( working_directory, flag )

    for path_flag in path_flags:
      if flag == path_flag:
        make_next_absolute = True
        break

      if flag.startswith( path_flag ):
        path = flag[ len( path_flag ): ]
        new_flag = path_flag + os.path.join( working_directory, path )
        break

    if new_flag:
      new_flags.append( new_flag )
  return new_flags


def FlagsForFile(filename, **kwargs):
  base_flags = [
    '-Wall',
    '-Wextra',
    '-Werror'
    '-pedantic',
    '-I',
    '.'
  ]
  extra_flags = []

  data = kwargs['client_data']
  filetype = data['&filetype']

  if filetype == 'c':
    language = 'c'
  elif filetype == 'cpp':
    language = 'c++'
    extra_flags += ['-std=c++11']
  elif filetype == 'objc':
    language = 'objective-c'

  flags = base_flags + extra_flags + ['-x', language] + LoadSystemIncludes(language)

  relative_to = DirectoryOfThisScript()
  final_flags = MakeRelativePathsInFlagsAbsolute( flags, relative_to )

  return {
    'flags': final_flags
}