"""
The module provides general format information and mappings of
XML and RDF attributes to their Python class equivalents.
"""

import sys

from rdflib import Namespace

import odml


class Format(object):
    """
    Base format class for all odML object formats. The formats are required
    when the corresponding odML objects are serialized to or loaded from files.
    """
    _name = ""
    _args = {}
    _map = {}
    _rev_map = None
    _rdf_map = {}
    _rdf_type = None
    _ns = Namespace("https://g-node.org/odml-rdf#")

    @property
    def name(self):
        """Returns the name of the current odML format"""
        return self._name

    @property
    def arguments(self):
        """Returns all items in the current odML format argument dict"""
        return self._args.items()

    @property
    def arguments_keys(self):
        """Returns all keys of the current odML format argument dict"""
        return self._args.keys()

    def map(self, name):
        """ Maps an odml name to a python name """
        return self._map.get(name, name)

    @property
    def map_keys(self):
        """Returns all keys of the current odML format map dict"""
        return self._map.keys()

    def rdf_map(self, name):
        """ Maps a python name to a odml rdf namespace """
        return self._rdf_map.get(name, name)

    @property
    def rdf_map_keys(self):
        """Returns all keys of the current odML format RDF map dict"""
        return self._rdf_map.keys()

    @property
    def rdf_map_items(self):
        """Returns all items of the current odML format RDF map dict"""
        return self._rdf_map.items()

    @property
    def rdf_type(self):
        """ Return rdf type of an object """
        return self._rdf_type

    @staticmethod
    def namespace():
        """ Return current link to current odml namespace"""
        return Format._ns

    def revmap(self, name):
        """ Maps a python name to an odml name """
        if self._rev_map is None:
            # create the reverse map only if requested
            self._rev_map = {}
            if sys.version_info < (3, 0):
                for k, val in self._map.iteritems():
                    self._rev_map[val] = k
            else:
                for k, val in self._map.items():
                    self._rev_map[val] = k

        return self._rev_map.get(name)

    def __iter__(self):
        """ Iterates each python property name """
        for k in self._args:
            yield self.map(k)

    def create(self, *args, **kargs):
        """
        This method will call the init method of the odML class implementation
        corresponding to the specific format odML class and return the initialised
        class instance. e.g. format.Document.create() will return an initialised
        odml.Document instance.
        """
        return getattr(odml, self.__class__.__name__)(*args, **kargs)


class Property(Format):
    """
    The format class for the odml Property class.
    """
    _name = "property"
    _ns = Format._ns
    _rdf_type = _ns.Property
    _args = {
        'id': 0,
        'name': 1,
        'value': 0,
        'unit': 0,
        'definition': 0,
        'dependency': 0,
        'dependencyvalue': 0,
        'uncertainty': 0,
        'reference': 0,
        'type': 0,
        'value_origin': 0,
        'val_cardinality': 0
    }
    _map = {
        'dependencyvalue': 'dependency_value',
        'type': 'dtype',
        'id': 'oid',
        'value': 'values'
    }
    _rdf_map = {
        'id': _ns.hasId,
        'name': _ns.hasName,
        'definition': _ns.hasDefinition,
        'dtype': _ns.hasDtype,
        'unit': _ns.hasUnit,
        'uncertainty': _ns.hasUncertainty,
        'reference': _ns.hasReference,
        'value': _ns.hasValue,
        'value_origin': _ns.hasValueOrigin
    }


class Section(Format):
    """
    The format class for the odml Section class.
    """
    _name = "section"
    _ns = Format._ns
    _rdf_type = _ns.Section
    _args = {
        'id': 0,
        'type': 1,
        'name': 1,
        'definition': 0,
        'reference': 0,
        'link': 0,
        'repository': 0,
        'section': 0,
        'include': 0,
        'property': 0,
        'sec_cardinality': 0,
        'prop_cardinality': 0
    }
    _map = {
        'section': 'sections',
        'property': 'properties',
        'id': 'oid'
    }
    _rdf_map = {
        'id': _ns.hasId,
        'name': _ns.hasName,
        'definition': _ns.hasDefinition,
        'type': _ns.hasType,
        'repository': _ns.hasTerminology,
        'reference': _ns.hasReference,
        'sections': _ns.hasSection,
        'properties': _ns.hasProperty,
    }


class Document(Format):
    """
    The format class for the odml Document class.
    """
    _name = "odML"
    _ns = Format._ns
    _rdf_type = _ns.Document
    _args = {
        'id': 0,
        'version': 0,
        'author': 0,
        'date': 0,
        'section': 0,
        'repository': 0,
    }
    _map = {
        'section': 'sections',
        'id': 'oid'
    }
    _rdf_map = {
        'id': _ns.hasId,
        'author': _ns.hasAuthor,
        'date': _ns.hasDate,
        'version': _ns.hasDocVersion,
        'repository': _ns.hasTerminology,
        'sections': _ns.hasSection
    }


Document = Document()
Section = Section()
Property = Property()

__all__ = [Document, Section, Property]