"""
Copyright 2008-2011 Free Software Foundation, Inc.
This file is part of GNU Radio

GNU Radio Companion is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License
as published by the Free Software Foundation; either version 2
of the License, or (at your option) any later version.

GNU Radio Companion 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 General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA
"""

from . import odict
from Element import Element

def _get_keys(lst): return [elem.get_key() for elem in lst]
def _get_elem(lst, key):
    try: return lst[_get_keys(lst).index(key)]
    except ValueError: raise ValueError, 'Key "%s" not found in %s.'%(key, _get_keys(lst))

class Option(Element):

    def __init__(self, param, n):
        Element.__init__(self, param)
        self._name = n.find('name')
        self._key = n.find('key')
        self._opts = dict()
        opts = n.findall('opt')
        #test against opts when non enum
        if not self.get_parent().is_enum() and opts:
            raise Exception, 'Options for non-enum types cannot have sub-options'
        #extract opts
        for opt in opts:
            #separate the key:value
            try: key, value = opt.split(':')
            except: raise Exception, 'Error separating "%s" into key:value'%opt
            #test against repeated keys
            if self._opts.has_key(key):
                raise Exception, 'Key "%s" already exists in option'%key
            #store the option
            self._opts[key] = value

    def __str__(self): return 'Option %s(%s)'%(self.get_name(), self.get_key())
    def get_name(self): return self._name
    def get_key(self): return self._key

    ##############################################
    # Access Opts
    ##############################################
    def get_opt_keys(self): return self._opts.keys()
    def get_opt(self, key): return self._opts[key]
    def get_opts(self): return self._opts.values()

class Param(Element):

    def __init__(self, block, n):
        """
        Make a new param from nested data.

        Args:
            block: the parent element
            n: the nested odict
        """
        # if the base key is a valid param key, copy its data and overlay this params data
        base_key = n.find('base_key')
        if base_key and base_key in block.get_param_keys():
            n_expanded = block.get_param(base_key)._n.copy()
            n_expanded.update(n)
            n = n_expanded
        # save odict in case this param will be base for another
        self._n = n
        # parse the data
        self._name = n.find('name')
        self._key = n.find('key')
        value = n.find('value') or ''
        self._type = n.find('type') or 'raw'
        self._hide = n.find('hide') or ''
        self._tab_label = n.find('tab') or block.get_param_tab_labels()[0]
        if not self._tab_label in block.get_param_tab_labels():
            block.get_param_tab_labels().append(self._tab_label)
        #build the param
        Element.__init__(self, block)
        #create the Option objects from the n data
        self._options = list()
        for option in map(lambda o: Option(param=self, n=o), n.findall('option')):
            key = option.get_key()
            #test against repeated keys
            if key in self.get_option_keys():
                raise Exception, 'Key "%s" already exists in options'%key
            #store the option
            self.get_options().append(option)
        #test the enum options
        if self.is_enum():
            #test against options with identical keys
            if len(set(self.get_option_keys())) != len(self.get_options()):
                raise Exception, 'Options keys "%s" are not unique.'%self.get_option_keys()
            #test against inconsistent keys in options
            opt_keys = self.get_options()[0].get_opt_keys()
            for option in self.get_options():
                if set(opt_keys) != set(option.get_opt_keys()):
                    raise Exception, 'Opt keys "%s" are not identical across all options.'%opt_keys
            #if a value is specified, it must be in the options keys
            self._value = value if value or value in self.get_option_keys() else self.get_option_keys()[0]
            if self.get_value() not in self.get_option_keys():
                raise Exception, 'The value "%s" is not in the possible values of "%s".'%(self.get_value(), self.get_option_keys())
        else: self._value = value or ''

    def validate(self):
        """
        Validate the param.
        The value must be evaluated and type must a possible type.
        """
        Element.validate(self)
        if self.get_type() not in self.get_types():
            self.add_error_message('Type "%s" is not a possible type.'%self.get_type())

    def get_evaluated(self): raise NotImplementedError

    def to_code(self):
        """
        Convert the value to code.
        @throw NotImplementedError
        """
        raise NotImplementedError

    def get_types(self):
        """
        Get a list of all possible param types.
        @throw NotImplementedError
        """
        raise NotImplementedError

    def get_color(self): return '#FFFFFF'
    def __str__(self): return 'Param - %s(%s)'%(self.get_name(), self.get_key())
    def is_param(self): return True
    def get_name(self): return self._name
    def get_key(self): return self._key
    def get_hide(self): return self.get_parent().resolve_dependencies(self._hide).strip()

    def get_value(self):
        value = self._value
        if self.is_enum() and value not in self.get_option_keys():
            value = self.get_option_keys()[0]
            self.set_value(value)
        return value

    def set_value(self, value): self._value = str(value) #must be a string

    def get_type(self): return self.get_parent().resolve_dependencies(self._type)
    def get_tab_label(self): return self._tab_label
    def is_enum(self): return self._type == 'enum'

    def __repr__(self):
        """
        Get the repr (nice string format) for this param.
        Just return the value (special case enum).
        Derived classes can handle complex formatting.

        Returns:
            the string representation
        """
        if self.is_enum(): return self.get_option(self.get_value()).get_name()
        return self.get_value()

    ##############################################
    # Access Options
    ##############################################
    def get_option_keys(self): return _get_keys(self.get_options())
    def get_option(self, key): return _get_elem(self.get_options(), key)
    def get_options(self): return self._options

    ##############################################
    # Access Opts
    ##############################################
    def get_opt_keys(self): return self.get_option(self.get_value()).get_opt_keys()
    def get_opt(self, key): return self.get_option(self.get_value()).get_opt(key)
    def get_opts(self): return self.get_option(self.get_value()).get_opts()

    ##############################################
    ## Import/Export Methods
    ##############################################
    def export_data(self):
        """
        Export this param's key/value.

        Returns:
            a nested data odict
        """
        n = odict()
        n['key'] = self.get_key()
        n['value'] = self.get_value()
        return n
