#!/usr/bin/env python
""" Adds links in the manual pages to implementations of the function"""

import os
import re

def processfile(petsc_dir,dir,file,implsClassAll,implsFuncAll):
  #print('Processing '+os.path.join(dir,file))
  itemName = file[0:-3]
  func = list(filter(lambda x: x.find(itemName+'_') > -1, implsFuncAll))
  iclass = list(filter(lambda x: x.find('_p_'+itemName) > -1, implsClassAll))
  if func or iclass:
    with open(os.path.join(dir,file),'a') as f:
      f.write('\n## Implementations\n')
      if func:
        for str in func:
          f.write(re.sub('(.*\.[ch]x*u*).*('+itemName+'.*)(\(.*\))','<A HREF=\"PETSC_DOC_OUT_ROOT_PLACEHOLDER/\\1.html#\\2\">\\2() in \\1</A><BR>',str,count=1)+'\n')
      if iclass:
        for str in iclass:
          f.write(re.sub('(.*\.[ch]x*u*):.*struct.*(_p_'+itemName+').*{','<A HREF=\"PETSC_DOC_OUT_ROOT_PLACEHOLDER/\\1.html#\\2\">\\2 in \\1</A><BR>',str,count=1)+'\n')

def loadstructfunctions(petsc_dir):
  '''Creates the list of structs and class functions'''
  import subprocess
  implsClassAll = subprocess.check_output(['git', 'grep', '-E', 'struct[[:space:]]+_[pn]_[^[:space:]]+.*\{', '--', '*.c', '*.cpp', '*.cu', '*.c', '*.h', '*.cxx'], cwd = petsc_dir).strip().decode('utf-8')
  implsClassAll = list(filter(lambda x: not (x.find('/tests/') > -1 or x.find('/tutorials') > -1 or x.find(';') > -1), implsClassAll.split('\n')))

  implsFuncAll = subprocess.check_output(['git', 'grep', '-nE', '^(static )?(PETSC_EXTERN )?(PETSC_INTERN )?(extern )?PetscErrorCode +[^_ ]+_[^_ ]+\(', '--', '*/impls/*.c', '*/impls/*.cpp', '*/impls/*.cu', '*/impls/*.c', '*/impls/*.h', '*/impls/*.cxx'], cwd = petsc_dir).strip().decode('utf-8')
  implsFuncAll = list(filter(lambda x: not (x.find('_Private') > -1 or x.find('_private') > -1 or x.find(';') > -1), implsFuncAll.split('\n')))
  return (implsClassAll,implsFuncAll)

def main(petsc_dir):
    (implsClassAll,implsFuncAll) = loadstructfunctions(petsc_dir)
    for dirpath, dirnames, filenames in os.walk(os.path.join(petsc_dir,'doc','manualpages'),topdown=True):
      #print('Processing directory '+dirpath)
      for file in filenames:
        if file.endswith('.md'): processfile(petsc_dir,dirpath,file,implsClassAll,implsFuncAll)

if __name__ == "__main__":
   main(os.path.abspath(os.environ['PETSC_DIR']))