#!/usr/bin/python

import os, sys, subprocess

abspath = os.path.abspath(os.path.dirname(__file__))
def path_from_root(*pathelems):
  return os.path.join(os.path.sep, *(abspath.split(os.sep) + list(pathelems)))
exec(open(path_from_root('tools', 'shared.py'), 'r').read())

COMPILER = path_from_root('src', 'compiler.js')

def emscripten(filename, settings, outfile):
  data = open(filename, 'r').read()
  try:
    cwd = os.getcwd()
  except:
    cwd = None
  os.chdir(os.path.dirname(COMPILER))
  subprocess.Popen(COMPILER_ENGINE + [COMPILER], stdin=subprocess.PIPE, stdout=outfile, stderr=subprocess.STDOUT).communicate(settings+'\n'+data)
  if outfile: outfile.close()
  if cwd is not None:
    os.chdir(cwd)

if __name__ == '__main__':
  if sys.argv.__len__() not in range(2,6):
    print '''
Emscripten usage:    emscripten.py INFILE [SETTINGS] [OUTPUT_FILE]

  INFILE must be in human-readable LLVM disassembly form (i.e., as text,
      not binary).
  SETTINGS is an optional set of compiler settings, overriding the defaults,
      in JSON format. See src/settings.js.
  OUTPUT_FILE is the file to create with the output. If not given, we write
      to stdout.

  You should have an ~/.emscripten file set up, see tests/settings.py, which
      in particular includes COMPILER_ENGINE.
'''
  else:
    settings = sys.argv[2] if len(sys.argv) >= 3 else "{}"
    outfile = open(sys.argv[3], 'w') if len(sys.argv) >= 4 else None
    emscripten(sys.argv[1], settings, outfile)