text: # MIT License
  #
  # Copyright The SCons Foundation
  #
  # Permission is hereby granted, free of charge, to any person obtaining
  # a copy of this software and associated documentation files (the
  # "Software"), to deal in the Software without restriction, including
  # without limitation the rights to use, copy, modify, merge, publish,
  # distribute, sublicense, and/or sell copies of the Software, and to
  # permit persons to whom the Software is furnished to do so, subject to
  # the following conditions:
  #
  # The above copyright notice and this permission notice shall be included
  # in all copies or substantial portions of the Software.
  #
  # THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY
  # KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE
  # WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  # NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  # LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  # OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  # WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  
  """Add user-friendly customizable variables to an SCons build. """
  
  import os.path
  import sys
  from functools import cmp_to_key
  
  import SCons.Environment
  import SCons.Errors
  import SCons.Util
  import SCons.Warnings
  
  from .BoolVariable import BoolVariable  # okay
  from .EnumVariable import EnumVariable  # okay
  from .ListVariable import ListVariable  # naja
  from .PackageVariable import PackageVariable # naja
  from .PathVariable import PathVariable # okay
  
  
  class Variables:
      """
      Holds all the options, updates the environment with the variables,
      and renders the help text.
  
      If is_global is True, this is a singleton, create only once.
  
      Args:
        files (optional): List of option configuration files to load
          (backward compatibility). If a single string is passed it is
          automatically placed in a file list (Default value = None)
        args (optional): dictionary to override values set from *files*.
          (Default value = None)
        is_global (optional): global instance? (Default value = True)
  
      """
      instance = None
  
      def __init__(self, files=None, args=None, is_global=True):
          if args is None:
              args = {}
          self.options = []
          self.args = args
          if not SCons.Util.is_List(files):
              if files:
                  files = [ files ]
              else:
                  files = []
          self.files = files
          self.unknown = {}
  
          # create the singleton instance
          if is_global:
              self = Variables.instance
  
              if not Variables.instance:
                  Variables.instance=self
  
      def _do_add(self, key, help="", default=None, validator=None, converter=None):
          class Variable:
              pass
  
          option = Variable()
  
          # if we get a list or a tuple, we take the first element as the
          # option key and store the remaining in aliases.
          if SCons.Util.is_List(key) or SCons.Util.is_Tuple(key):
              option.key     = key[0]
              option.aliases = key[1:]
          else:
              option.key     = key
              option.aliases = [ key ]
          option.help = help
          option.default = default
          option.validator = validator
          option.converter = converter
  
          self.options.append(option)
  
          # options might be added after the 'unknown' dict has been set up,
          # so we remove the key and all its aliases from that dict
          for alias in list(option.aliases) + [ option.key ]:
              if alias in self.unknown:
                  del self.unknown[alias]
  
      def keys(self):
          """
          Returns the keywords for the options
          """
          return [o.key for o in self.options]
  
      def Add(self, key, help="", default=None, validator=None, converter=None, **kw):
          """Add an option.
  
          Args:
            key: the name of the variable, or a list or tuple of arguments
            help: optional help text for the options (Default value = "")
            default: optional default value for option (Default value = None)
            validator: optional function called to validate the option's value
              (Default value = None)
            converter: optional function to be called to convert the option's
              value before putting it in the environment. (Default value = None)
            \*\*kw: keyword args, unused.
  
          """
          if SCons.Util.is_List(key) or isinstance(key, tuple):
              self._do_add(*key)
              return
  
          if not SCons.Util.is_String(key) or \
              not SCons.Environment.is_valid_construction_var(key):
                  raise SCons.Errors.UserError("Illegal Variables.Add() key `%s'" % str(key))
  
          self._do_add(key, help, default, validator, converter)
  
      def AddVariables(self, *optlist):
          """
          Add a list of options.
  
          Each list element is a tuple/list of arguments to be passed on
          to the underlying method for adding options.
  
          Example::
  
              opt.AddVariables(
                  ('debug', '', 0),
                  ('CC', 'The C compiler'),
                  ('VALIDATE', 'An option for testing validation', 'notset', validator, None),
              )
  
          """
  
          for o in optlist:
              self._do_add(*o)
  
  
      def Update(self, env, args=None):
          """
          Update an environment with the option variables.
  
          env - the environment to update.
          """
  
          values = {}
  
          # first set the defaults:
          for option in self.options:
              if option.default is not None:
                  values[option.key] = option.default
  
          # next set the value specified in the options file
          for filename in self.files:
              if os.path.exists(filename):
                  dir = os.path.split(os.path.abspath(filename))[0]
                  if dir:
                      sys.path.insert(0, dir)
                  try:
                      values['__name__'] = filename
                      with open(filename, 'r') as f:
                          contents = f.read()
                      exec(contents, {}, values)
                  finally:
                      if dir:
                          del sys.path[0]
                      del values['__name__']
  
          # set the values specified on the command line
          if args is None:
              args = self.args
  
          for arg, value in args.items():
              added = False
              for option in self.options:
                  if arg in list(option.aliases) + [ option.key ]:
                      values[option.key] = value
                      added = True
              if not added:
                  self.unknown[arg] = value
  
          # put the variables in the environment:
          # (don't copy over variables that are not declared as options)
          for option in self.options:
              try:
                  env[option.key] = values[option.key]
              except KeyError:
                  pass
  
          # Call the convert functions:
          for option in self.options:
              if option.converter and option.key in values:
                  value = env.subst('${%s}'%option.key)
                  try:
                      try:
                          env[option.key] = option.converter(value)
                      except TypeError:
                          env[option.key] = option.converter(value, env)
                  except ValueError as x:
                      raise SCons.Errors.UserError('Error converting option: %s\n%s'%(option.key, x))
  
  
          # Finally validate the values:
          for option in self.options:
              if option.validator and option.key in values:
                  option.validator(option.key, env.subst('${%s}'%option.key), env)
  
      def UnknownVariables(self):
          """
          Returns any options in the specified arguments lists that
          were not known, declared options in this object.
          """
          return self.unknown
  
      def Save(self, filename, env):
          """
          Saves all the options in the given file.  This file can
          then be used to load the options next run.  This can be used
          to create an option cache file.
  
          filename - Name of the file to save into
          env - the environment get the option values from
          """
  
          # Create the file and write out the header
          try:
              fh = open(filename, 'w')
  
              try:
                  # Make an assignment in the file for each option
                  # within the environment that was assigned a value
                  # other than the default.
                  for option in self.options:
                      try:
                          value = env[option.key]
                          try:
                              prepare = value.prepare_to_store
                          except AttributeError:
                              try:
                                  eval(repr(value))
                              except KeyboardInterrupt:
                                  raise
                              except:
                                  # Convert stuff that has a repr() that
                                  # cannot be evaluated into a string
                                  value = SCons.Util.to_String(value)
                          else:
                              value = prepare()
  
                          defaultVal = env.subst(SCons.Util.to_String(option.default))
                          if option.converter:
                              defaultVal = option.converter(defaultVal)
  
                          if str(env.subst('${%s}' % option.key)) != str(defaultVal):
                              fh.write('%s = %s\n' % (option.key, repr(value)))
                      except KeyError:
                          pass
              finally:
                  fh.close()
  
          except IOError as x:
              raise SCons.Errors.UserError('Error writing options to file: %s\n%s' % (filename, x))
  
      def GenerateHelpText(self, env, sort=None):
          """
          Generate the help text for the options.
  
          env - an environment that is used to get the current values
                of the options.
          cmp - Either a function as follows: The specific sort function should take two arguments and return -1, 0 or 1
                or a boolean to indicate if it should be sorted.
          """
  
          if callable(sort):
              options = sorted(self.options, key=cmp_to_key(lambda x,y: sort(x.key,y.key)))
          elif sort is True:
              options = sorted(self.options, key=lambda x: x.key)
          else:
              options = self.options
  
          def format(opt, self=self, env=env):
              if opt.key in env:
                  actual = env.subst('${%s}' % opt.key)
              else:
                  actual = None
              return self.FormatVariableHelpText(env, opt.key, opt.help, opt.default, actual, opt.aliases)
          lines = [_f for _f in map(format, options) if _f]
  
          return ''.join(lines)
  
      format  = '\n%s: %s\n    default: %s\n    actual: %s\n'
      format_ = '\n%s: %s\n    default: %s\n    actual: %s\n    aliases: %s\n'
  
      def FormatVariableHelpText(self, env, key, help, default, actual, aliases=[]):
          # Don't display the key name itself as an alias.
          aliases = [a for a in aliases if a != key]
          if len(aliases)==0:
              return self.format % (key, help, default, actual)
          else:
              return self.format_ % (key, help, default, actual, aliases)
  
  # Local Variables:
  # tab-width:4
  # indent-tabs-mode:nil
  # End:
  # vim: set expandtab tabstop=4 shiftwidth=4:
  