# Copyright (C) 2013-2019  CEA/DEN, EDF R&D, OPEN CASCADE
#
# This library is free software; you can redistribute it and/or
# modify it under the terms of the GNU Lesser General Public
# License as published by the Free Software Foundation; either
# version 2.1 of the License, or (at your option) any later version.
#
# This library is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
# Lesser General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public
# License along with this library; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
#
# See http://www.salome-platform.org/ or email : webmaster.salome@opencascade.com
#

import os
import sys
import glob
import subprocess
import re
import socket
import json

"""
Define a specific exception class to manage exceptions related to SalomeContext
"""
class SalomeContextException(Exception):
  """Report error messages to the user interface of SalomeContext."""
#

def __listDirectory(path):
  allFiles = []
  for root, dirs, files in os.walk(path):
    cfgFiles = glob.glob(os.path.join(root,'*.cfg'))
    allFiles += cfgFiles

  return allFiles
#

def __getConfigFileNamesDefault():
  absoluteAppliPath = os.getenv('ABSOLUTE_APPLI_PATH','')
  if not absoluteAppliPath:
    return []

  envdDir = absoluteAppliPath + '/env.d'
  if not os.path.isdir(envdDir):
    return []

  return __listDirectory(envdDir)
#

def __getEnvironmentFileNames(args, optionPrefix, checkExistence):
  # special case: extra configuration/environment files are provided by user
  # Search for command-line argument(s) <optionPrefix>=file1,file2,..., filen
  # Search for command-line argument(s) <optionPrefix>=dir1,dir2,..., dirn
  configArgs = [ str(x) for x in args if str(x).startswith(optionPrefix) ]

  args = [ x for x in args if not x.startswith(optionPrefix) ]
  allLists = [ x.replace(optionPrefix, '') for x in configArgs ]

  configFileNames = []
  unexisting = []
  for currentList in allLists:
    elements = currentList.split(',')
    for elt in elements:
      elt = os.path.realpath(os.path.expanduser(elt))
      if os.path.isdir(elt):
        configFileNames += __listDirectory(elt)
      else:
        if checkExistence and not os.path.isfile(elt):
          unexisting += [elt]
        else:
          configFileNames += [elt]

  return configFileNames, args, unexisting
#

def getConfigFileNames(args, checkExistence=False):
  configOptionPrefix = "--config="
  configArgs = [ str(x) for x in args if str(x).startswith(configOptionPrefix) ]
  if len(configArgs) == 0:
    configFileNames, unexist = __getConfigFileNamesDefault(), []
  else:
    # get configuration filenames
    configFileNames, args, unexist = __getEnvironmentFileNames(args, configOptionPrefix, checkExistence)

  return configFileNames, args, unexist
#

def __getScriptPath(scriptName, searchPathList):
  scriptName = os.path.expanduser(scriptName)
  if os.path.isabs(scriptName):
    return scriptName

  if searchPathList is None or len(searchPathList) == 0:
    return None

  for path in searchPathList:
    fullName = os.path.join(path, scriptName)
    if os.path.isfile(fullName) or os.path.isfile(fullName+".py"):
      return fullName

  return None
#

class ScriptAndArgs:
  # script: the command to be run, e.g. python <script.py>
  # args: its input parameters
  # out: its output parameters
  def __init__(self, script=None, args=None, out=None):
    self.script = script
    self.args = args
    self.out = out
  #
  def __repr__(self):
    msg = "\n# Script: %s\n"%self.script
    msg += "     * Input: %s\n"%self.args
    msg += "     * Output: %s\n"%self.out
    return msg
  #
#
class ScriptAndArgsObjectEncoder(json.JSONEncoder):
  def default(self, obj):
    if isinstance(obj, ScriptAndArgs):
      # to be easily parsed in GUI module (SalomeApp_Application)
      # Do not export output arguments
      return {obj.script:obj.args or []}
    else:
      return json.JSONEncoder.default(self, obj)
#

def getShortAndExtraArgs(args=None):
  if args is None:
    args = []
  try:
    pos = args.index("--") # raise a ValueError if not found
    short_args = args[:pos]
    extra_args = args[pos:] # include "--"
  except ValueError:
    short_args = args
    extra_args = []
    pass

  return short_args, extra_args
#

# Return an array of ScriptAndArgs objects
def getScriptsAndArgs(args=None, searchPathList=None):
  if args is None:
    args = []
  short_args, extra_args = getShortAndExtraArgs(args)
  args = short_args

  if searchPathList is None:
    searchPathList = sys.path

  # Syntax of args: script.py [args:a1,a2=val,an] ... script.py [args:a1,a2=val,an]
  scriptArgs = []
  currentKey = None
  argsPrefix = "args:"
  outPrefix = "out:"
  callPython = False
  afterArgs = False
  currentScript = None

  for i in range(len(args)):
    elt = os.path.expanduser(args[i])
    isDriver = (elt == "driver") # special case for YACS scheme execution

    if elt.startswith(argsPrefix):
      if not currentKey or callPython:
        raise SalomeContextException("args list must follow corresponding script file in command line.")
      elt = elt.replace(argsPrefix, '')
      # Special process if some items of 'args:' list are themselves lists
      # Note that an item can be a list, but not a list of lists...
      # So we can have something like this:
      # myscript.py args:['file1','file2'],val1,"done",[1,2,3],[True,False],"ok"
      # With such a call, an elt variable contains the string representing ['file1','file2'],val1,"done",[1,2,3],[True,False],"ok" that is '[file1,file2],val1,done,[1,2,3],[True,False],ok'
      # We have to split elt to obtain: ['[file1,file2]','val1','done','[1,2,3]','[True,False]','ok']
      contains_list = re.findall('(\[[^\]]*\])', elt)
      if contains_list:
        extracted_args = []
        x = elt.split(",")
        # x is ['[file1', 'file2]', 'val1', 'done', '[1', '2', '3]', '[True', 'False]', 'ok']
        list_begin_indices = [i for i in range(len(x)) if x[i].startswith('[')] # [0, 4, 7]
        list_end_indices = [i for i in range(len(x)) if x[i].endswith(']')] # [1, 6, 8]
        start = 0
        for lbeg, lend in zip(list_begin_indices,list_end_indices): # [(0, 1), (4, 6), (7, 8)]
          if lbeg > start:
            extracted_args += x[start:lbeg]
            pass
          extracted_args += [','.join(x[lbeg:lend+1])]
          start = lend+1
          pass
        if start < len(x):
          extracted_args += x[start:len(x)]
          pass
        scriptArgs[len(scriptArgs)-1].args = extracted_args
        pass
      else: # a single split is enough
        scriptArgs[len(scriptArgs)-1].args = [os.path.expanduser(x) for x in elt.split(",")]
        pass
      currentKey = None
      callPython = False
      afterArgs = True
    elif elt.startswith(outPrefix):
      if (not currentKey and not afterArgs) or callPython:
        raise SalomeContextException("out list must follow both corresponding script file and its args in command line.")
      elt = elt.replace(outPrefix, '')
      scriptArgs[len(scriptArgs)-1].out = [os.path.expanduser(x) for x in elt.split(",")]
      currentKey = None
      callPython = False
      afterArgs = False
    elif elt.startswith("python"):
      callPython = True
      afterArgs = False
    else:
      elt = elt.strip('"')  # CP-1314 for CENOS
      file_extension = os.path.splitext(elt)[-1]
      if not os.path.isfile(elt) and not os.path.isfile(elt+".py"):
        eltInSearchPath = __getScriptPath(elt, searchPathList)
        if eltInSearchPath is None or (not os.path.isfile(eltInSearchPath) and not os.path.isfile(eltInSearchPath+".py")):
          if file_extension == ".py":
            raise SalomeContextException("Script not found: %s"%elt)
          scriptArgs.append(ScriptAndArgs(script=elt))
          continue
        elt = eltInSearchPath

      if file_extension != ".hdf":
        if file_extension == ".py" or isDriver:
          currentScript = os.path.abspath(elt)
        elif os.path.isfile(elt+".py"):
          currentScript = os.path.abspath(elt+".py")
        else:
          currentScript = os.path.abspath(elt) # python script not necessary has .py extension
        pass

      if currentScript and callPython:
       # currentKey = "python3.exe "+currentScript # CP-1314 for CENOS
        currentKey = "python3.exe \""+currentScript + "\"" # CP-1314 for CENOS
        scriptArgs.append(ScriptAndArgs(script=currentKey))
        callPython = False
      elif currentScript:
        script_extension = os.path.splitext(currentScript)[-1]
        if isDriver:
          currentKey = currentScript
          scriptArgs.append(ScriptAndArgs(script=currentKey))
          callPython = False
        elif not os.access(currentScript, os.X_OK):
          # currentKey = "python3.exe "+currentScript # CP-1314 for CENOS
          currentKey = "python3.exe \""+currentScript + "\"" # CP-1314 for CENOS
          scriptArgs.append(ScriptAndArgs(script=currentKey))
        else:
          ispython = False
          try:
            fn = open(currentScript)
            for i in range(10): # read only 10 first lines
              ln = fn.readline()
              if re.search("#!.*python"):
                ispython = True
                break
              pass
            fn.close()
          except:
            pass
          if not ispython and script_extension == ".py":
            # currentKey = "python3.exe "+currentScript # CP-1314 for CENOS
            currentKey = "python3.exe \""+currentScript + "\"" # CP-1314 for CENOS
          else:
            currentKey = currentScript
            pass
          scriptArgs.append(ScriptAndArgs(script=currentKey))
      # CLOSE elif currentScript
      afterArgs = False
  # end for loop

  if len(extra_args) > 1: # syntax: -- program [options] [arguments]
    command = extra_args[1]
    command_args = extra_args[2:]
    scriptArgs.append(ScriptAndArgs(script=command, args=command_args))
    pass

  return scriptArgs
#

# Formatting scripts and args as a Bash-like command-line:
# script1.py [args] ; script2.py [args] ; ...
# scriptArgs is a list of ScriptAndArgs objects; their output parameters are omitted
def formatScriptsAndArgs(scriptArgs=None):
    if scriptArgs is None:
      return ""
    commands = []
    for sa_obj in scriptArgs:
      cmd = sa_obj.script
      if sa_obj.args:
        cmd = " ".join([cmd]+sa_obj.args)
      commands.append(cmd)

    sep = " ; "
    if sys.platform == "win32":
      sep = " & "
    command = sep.join(["%s"%x for x in commands])
    return command
#

# Ensure OMNIORB_USER_PATH is defined. This variable refers to a folder in which
# SALOME will write omniOrb configuration files.
# If OMNIORB_USER_PATH is already set, only checks write access to associated directory ;
# an exception is raised if check fails. It allows users for choosing a specific folder.
# Else the function sets OMNIORB_USER_PATH this way:
# - If APPLI environment variable is set, OMNIORB_USER_PATH is set to ${APPLI}/USERS.
#   The function does not check USERS folder existence or write access. This folder
#   must exist ; this is the case if SALOME virtual application has been created using
#   appli_gen.py script.
# - Else OMNIORB_USER_PATH is set to user home directory.
def setOmniOrbUserPath():
  omniorbUserPath = os.getenv("OMNIORB_USER_PATH")
  if omniorbUserPath:
    if not os.access(omniorbUserPath, os.W_OK):
      raise Exception("Unable to get write access to directory: %s"%omniorbUserPath)
    pass
  else:
    # Must be in /tmp (or equivalent) to handle application concurrency
    try:
      import tempfile
      temp = tempfile.NamedTemporaryFile()
      temp_dir = os.path.dirname(temp.name)
      temp.close()
      if not os.access(temp_dir, os.W_OK):
        raise Exception("Unable to get write access to directory: %s"%temp_dir)
      os.environ["OMNIORB_USER_PATH"] = temp_dir
    except:
      homePath = os.path.realpath(os.path.expanduser('~'))
      #defaultOmniorbUserPath = os.path.join(homePath, ".salomeConfig/USERS")
      defaultOmniorbUserPath = homePath
      if os.getenv("APPLI"):
        defaultOmniorbUserPath = os.path.join(homePath, os.getenv("APPLI"), "USERS")
        pass
      os.environ["OMNIORB_USER_PATH"] = defaultOmniorbUserPath
#

def getHostname():
  return socket.gethostname().split('.')[0]
#