# coding=utf8

# Copyright (c) 2015, Google Inc.
#
# Permission to use, copy, modify, and/or distribute this software for any
# purpose with or without fee is hereby granted, provided that the above
# copyright notice and this permission notice appear in all copies.
#
# THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
# WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
# MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
# SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
# WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
# OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
# CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

import io
import optparse
import os
import subprocess
import sys
import json
from string import Template

# OS_ARCH_COMBOS maps from OS and platform to the OpenSSL assembly "style" for
# that platform and the extension used by asm files.
OS_ARCH_COMBOS = [
    ('ios', 'arm', 'ios32', [], 'S'),
    ('ios', 'aarch64', 'ios64', [], 'S'),
    ('linux', 'arm', 'linux32', [], 'S'),
    ('linux', 'aarch64', 'linux64', [], 'S'),
    ('linux', 'ppc64le', 'linux64le', [], 'S'),
    ('linux', 'x86', 'elf', ['-fPIC', '-DOPENSSL_IA32_SSE2'], 'S'),
    ('linux', 'x86_64', 'elf', [], 'S'),
    ('mac', 'x86', 'macosx', ['-fPIC', '-DOPENSSL_IA32_SSE2'], 'S'),
    ('mac', 'x86_64', 'macosx', [], 'S'),
    ('win', 'x86', 'win32n', ['-DOPENSSL_IA32_SSE2'], 'asm'),
    ('win', 'x86_64', 'nasm', [], 'asm'),
    ('win', 'aarch64', 'win64', [], 'S'),
]

def FindCMakeFiles(directory):
  """Returns list of all CMakeLists.txt files recursively in directory."""
  cmakefiles = []

  for (path, _, filenames) in os.walk(directory):
    for filename in filenames:
      if filename == 'CMakeLists.txt':
        cmakefiles.append(os.path.join(path, filename))

  return cmakefiles

def FindCFiles(directory, filter_func):
  """Recurses through directory and returns a list of paths to all the C source
  files that pass filter_func."""
  cfiles = []

  for (path, dirnames, filenames) in os.walk(directory):
    for filename in filenames:
      if not filename.endswith('.c') and not filename.endswith('.cc'):
        continue
      if not filter_func(path, filename, False):
        continue
      cfiles.append(os.path.relpath(os.path.join(path, filename), DEST_DIR))

    for (i, dirname) in enumerate(dirnames):
      if not filter_func(path, dirname, True):
        del dirnames[i]

  cfiles.sort()
  return cfiles

def ExtractPerlAsmFromCMakeFile(cmakefile):
  """Parses the contents of the CMakeLists.txt file passed as an argument and
  returns a list of all the perlasm() directives found in the file."""
  perlasms = []
  with io.open(cmakefile, encoding="utf-8") as f:
    for line in f:
      line = line.strip()
      if not line.startswith('perlasm('):
        continue
      if not line.endswith(')'):
        raise ValueError('Bad perlasm line in %s' % cmakefile)
      # Remove "perlasm(" from start and ")" from end
      params = line[8:-1].split()
      if len(params) < 2:
        raise ValueError('Bad perlasm line in %s' % cmakefile)
      perlasms.append({
          'extra_args': params[2:],
          'input': os.path.join(os.path.dirname(cmakefile), params[1]),
          'output': os.path.join(os.path.relpath(os.path.dirname(cmakefile), SRC_DIR), params[0])
      })

  return perlasms

def ReadPerlAsmOperations():
  """Returns a list of all perlasm() directives found in CMake config files in
  src_dir"""
  perlasms = []
  cmakefiles = FindCMakeFiles(SRC_DIR)

  for cmakefile in cmakefiles:
    perlasms.extend(ExtractPerlAsmFromCMakeFile(cmakefile))

  return perlasms


def PerlAsm(output_filename, input_filename, perlasm_style, extra_args):
  """Runs the a perlasm script and puts the output into output_filename."""
  base_dir = os.path.dirname(output_filename)
  if not os.path.isdir(base_dir):
    os.makedirs(base_dir)
  subprocess.check_call(
      ['perl', input_filename, perlasm_style, output_filename] + extra_args)


def ArchForAsmFilename(filename):
  """Returns the architectures that a given asm file should be compiled for
  based on substrings in the filename."""

  if 'x86_64' in filename or 'avx2' in filename or 'avx512' in filename:
    return ['x86_64']
  elif ('x86' in filename and 'x86_64' not in filename) or '586' in filename:
    return ['x86']
  elif 'armx' in filename:
    return ['arm', 'aarch64']
  elif 'armv8' in filename:
    return ['aarch64']
  elif 'arm' in filename:
    return ['arm']
  elif 'ppc' in filename:
    return ['ppc64le']
  else:
    raise ValueError('Unknown arch for asm filename: ' + filename)


def WriteAsmFiles(perlasms):
  """Generates asm files from perlasm directives for each supported OS x
  platform combination."""

  for osarch in OS_ARCH_COMBOS:
    (osname, arch, perlasm_style, extra_args, asm_ext) = osarch
    key = (osname, arch)
    outDir = os.path.join(DEST_DIR, ('%s-%s' % key))

    for perlasm in perlasms:
      filename = os.path.basename(perlasm['input'])
      output = perlasm['output']
      output = os.path.relpath(os.path.join(outDir, output), DEST_DIR)
      output = output.replace('${ASM_EXT}', asm_ext)

      if arch in ArchForAsmFilename(filename):
        PerlAsm(os.path.join(DEST_DIR, output), perlasm['input'], perlasm_style,
                perlasm['extra_args'] + extra_args)

def ExtractVariablesFromCMakeFile(cmakefile):
  """Parses the contents of the CMakeLists.txt file passed as an argument and
  returns a dictionary of exported source lists."""
  variables = {}
  in_set_command = False
  set_command = []
  with open(cmakefile) as f:
    for line in f:
      if '#' in line:
        line = line[:line.index('#')]
      line = line.strip()

      if not in_set_command:
        if line.startswith('set('):
          in_set_command = True
          set_command = []
      elif line == ')':
        in_set_command = False
        if not set_command:
          raise ValueError('Empty set command')
        variables[set_command[0]] = set_command[1:]
      else:
        set_command.extend([c for c in line.split(' ') if c])

  if in_set_command:
    raise ValueError('Unfinished set command')
  return variables

def main():
  cmake = ExtractVariablesFromCMakeFile(os.path.join(SRC_DIR, 'sources.cmake'))

  # Generate err_data.c
  if not os.path.isdir(DEST_DIR):
    os.makedirs(DEST_DIR)

  with open(os.path.join(DEST_DIR, 'err_data.c'), 'w+') as err_data:
    subprocess.check_call(['go', 'run', 'err_data_generate.go'],
                          cwd=os.path.join(SRC_DIR, 'crypto', 'err'),
                          stdout=err_data)

  # Generate crypto_test_data.cc
  with open(os.path.join(DEST_DIR, 'crypto_test_data.cc'), 'w+') as out:
    subprocess.check_call(
        ['go', 'run', 'util/embed_test_data.go'] + cmake['CRYPTO_TEST_DATA'],
        cwd=SRC_DIR,
        stdout=out)

  WriteAsmFiles(ReadPerlAsmOperations())

  return 0

if __name__ == '__main__':
  usage = '''%prog

  This script generates intermediate build files for CMake builds without the
  need to install Go or Perl as a dependency. These files are output to the
  |generated-src| directory and are used by the top-level CMakeLists.txt if
  either Go or Perl are not found.
  '''

  parser = optparse.OptionParser(usage=usage)
  options, args = parser.parse_args(sys.argv[1:])

  SRC_DIR = os.getcwd()
  DEST_DIR = os.path.relpath('generated-src', os.getcwd())

  sys.exit(main())