# vim: set ts=8 sts=2 sw=2 tw=99 et:
import re
import os, sys
import subprocess

argv = sys.argv[1:]
if len(argv) < 2:
  sys.stderr.write('Usage: generate_headers.py <source_path> <output_folder>\n')
  sys.exit(1)

SourceFolder = os.path.abspath(os.path.normpath(argv[0]))
OutputFolder = os.path.normpath(argv[1])

class FolderChanger:
  def __init__(self, folder):
    self.old = os.getcwd()
    self.new = folder

  def __enter__(self):
    if self.new:
      os.chdir(self.new)

  def __exit__(self, type, value, traceback):
    os.chdir(self.old)

def run_and_return(argv):
  # Python 2.6 doesn't have check_output.
  if hasattr(subprocess, 'check_output'):
    text = subprocess.check_output(argv)
    if str != bytes:
      text = str(text, 'utf-8')
  else:
    p = subprocess.Popen(argv, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
    output, ignored = p.communicate()
    rval = p.poll()
    if rval:
      raise subprocess.CalledProcessError(rval, argv)
    text = output.decode('utf8')
  return text.strip()

def get_git_version():
  revision_count = run_and_return(['git', 'rev-list', '--count', 'HEAD'])
  revision_hash = run_and_return(['git', 'log', '--pretty=format:%h:%H', '-n', '1'])
  shorthash, longhash = revision_hash.split(':')

  return revision_count, shorthash, longhash

def output_version_headers():
  with FolderChanger(SourceFolder):
    count, shorthash, longhash = get_git_version()

  with open(os.path.join(SourceFolder, 'product.version')) as fp:
    contents = fp.read()
  m = re.match('(\d+)\.(\d+)\.(\d+)-?(.*)', contents)
  if m == None:
    raise Exception('Could not detremine product version')
  major, minor, release, tag = m.groups()
  product = "{0}.{1}.{2}".format(major, minor, release)
  fullstring = product
  if tag != "":
    fullstring += "-{0}".format(tag)
    if tag == "dev":
      fullstring += "+{0}".format(shorthash)

  with open(os.path.join(OutputFolder, 'amxmodx_version.h'), 'w') as fp:
    fp.write("""
#ifndef _AMXMODX_AUTO_VERSION_INFORMATION_H_
#define _AMXMODX_AUTO_VERSION_INFORMATION_H_

#define SVN_VERSION_STRING  "{fullstring}"
#define SVN_VERSION_DWORD   {major}, {minor}, {release}, 0
#define SVN_VERSION_PRODUCT "{product}"
#define SVN_VERSION         SVN_VERSION_STRING
#define SVN_BUILD_ID        "{count}:{longhash}"

#endif // _AMXMODX_AUTO_VERSION_INFORMATION_H_
    """.format(
      fullstring = fullstring,
      major = major,
      minor = minor,
      release = release,
      product = product,
      count = count,
      longhash = longhash
    ))

  version_num = int(major) * 100 + int(minor) * 10 + int(release)
  with open(os.path.join(OutputFolder, 'amxmodx_version.inc'), 'w') as fp:
    fp.write("""
#if defined _amxmodx_version_included
  #endinput
#endif
#define _amxmodx_version_included

#define AMXX_VERSION        {major}.{minor}{release}
#define AMXX_VERSION_NUM    {version_num}
stock const AMXX_VERSION_STR[] = "{fullstring}";
    """.format(
      major = major,
      minor = minor,
      release = release,
      version_num = version_num,
      fullstring = fullstring
    ))

output_version_headers()