import os


__version_info = {}

def get_version_info():
    # read from VERSION
    # return dictionary filled with content of version

    global __version_info
    if not __version_info:
      this_file_dir = os.path.dirname(os.path.abspath(__file__))
      version_file = os.path.join(this_file_dir,  'VERSION')

      if not os.path.isfile(version_file):
          raise SystemError("VERSION file not found.")


      for l in open(version_file).readlines():
        #exec (l.strip())
        if l.startswith('AUBIO_MAJOR_VERSION'):
            __version_info['AUBIO_MAJOR_VERSION'] = int(l.split('=')[1])
        if l.startswith('AUBIO_MINOR_VERSION'):
            __version_info['AUBIO_MINOR_VERSION'] = int(l.split('=')[1])
        if l.startswith('AUBIO_PATCH_VERSION'):
            __version_info['AUBIO_PATCH_VERSION'] = int(l.split('=')[1])
        if l.startswith('AUBIO_VERSION_STATUS'):
            __version_info['AUBIO_VERSION_STATUS'] = l.split('=')[1].strip()[1:-1]

        if l.startswith('LIBAUBIO_LT_CUR'):
          __version_info['LIBAUBIO_LT_CUR'] = int(l.split('=')[1])
        if l.startswith('LIBAUBIO_LT_REV'):
          __version_info['LIBAUBIO_LT_REV'] = int(l.split('=')[1])
        if l.startswith('LIBAUBIO_LT_AGE'):
          __version_info['LIBAUBIO_LT_AGE'] = int(l.split('=')[1])

      if len(__version_info) <6:
          raise SystemError("Failed parsing VERSION file.")


      # switch version status with commit sha in alpha releases
      if __version_info['AUBIO_VERSION_STATUS'] and \
      '~alpha' in __version_info['AUBIO_VERSION_STATUS'] :
          AUBIO_GIT_SHA = get_git_revision_hash()
          if AUBIO_GIT_SHA:
            __version_info['AUBIO_VERSION_STATUS'] = '~git'+AUBIO_GIT_SHA

    return __version_info


def get_aubio_version_tuple():
    d = get_version_info()
    return (d['AUBIO_MAJOR_VERSION'],d['AUBIO_MINOR_VERSION'],d['AUBIO_PATCH_VERSION'])

def get_libaubio_version_tuple():
    d = get_version_info()
    return (d['LIBAUBIO_LT_CUR'],d['LIBAUBIO_LT_REV'],d['LIBAUBIO_LT_AGE'])

def get_libaubio_version():
    return '%s.%s.%s'%get_libaubio_version_tuple()

def get_aubio_version(add_status = True):
    # return string formatted as MAJ.MIN.PATCH.{~git<sha> , ''}
    vdict = get_version_info()
    verstr = '%s.%s.%s'%get_aubio_version_tuple()
    if add_status and vdict['AUBIO_VERSION_STATUS']:
        verstr += "."+vdict['AUBIO_VERSION_STATUS']
    return verstr

def get_aubio_pyversion(add_status = True):
    # convert to version for python according to pep 440
    # see https://www.python.org/dev/peps/pep-0440/
    # outputs MAJ.MIN.PATCH+a0{.git<sha> , ''}
    vdict = get_version_info()
    verstr = '%s.%s.%s'%get_aubio_version_tuple()
    if add_status and vdict['AUBIO_VERSION_STATUS'] :
      if '~git' in vdict['AUBIO_VERSION_STATUS']:
        verstr += "+a0."+vdict['AUBIO_VERSION_STATUS'][1:]
      elif '~alpha':
        verstr += "+a0"
      else:
        raise SystemError("Aubio version statut not supported : %s"%vdict['AUBIO_VERSION_STATUS'])
    return verstr



def get_git_revision_hash( short=True):

    if not os.path.isdir('.git'):
        # print('Version : not in git repository : can\'t get sha')
        return None

    import subprocess
    aubio_dir = os.path.dirname(os.path.abspath(__file__))
    if not os.path.exists(aubio_dir):
        raise SystemError("git / root folder not found")
    gitcmd = ['git','-C',aubio_dir ,'rev-parse']
    if short:
      gitcmd.append('--short')
    gitcmd.append('HEAD')
    try:
      outCmd = subprocess.check_output(gitcmd).strip().decode('utf8')
    except Exception as e:
      print ('git command error :%s'%e)
      return None
    return outCmd