File: nexmlreader.py

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#! /usr/bin/env python

##############################################################################
##  DendroPy Phylogenetic Computing Library.
##
##  Copyright 2010-2015 Jeet Sukumaran and Mark T. Holder.
##  All rights reserved.
##
##  See "LICENSE.rst" for terms and conditions of usage.
##
##  If you use this work or any portion thereof in published work,
##  please cite it as:
##
##     Sukumaran, J. and M. T. Holder. 2010. DendroPy: a Python library
##     for phylogenetic computing. Bioinformatics 26: 1569-1571.
##
##############################################################################

"""
Deserialization of NeXML-formatted data.
"""

import re
import collections
from dendropy.dataio import ioservice
from dendropy.utility import container
from dendropy.utility import textprocessing
from dendropy.utility import error
from dendropy.dataio import xmlprocessing

SUPPORTED_NEXML_NAMESPACES = ('http://www.nexml.org/1.0', 'http://www.nexml.org/2009')

def _from_nexml_tree_length_type(type_attr):
    """
    Given an attribute string read from a nexml tree element, returns
    the python class of the edge length attribute.
    """
    if type_attr == "nex:IntTree":
        return int
    else:
        return float

class _AnnotationParser(object):

    def __init__(self, namespace_registry=None):
        self._namespace_registry = namespace_registry

    def _parse_annotations(self, annotated, nxelement):
        attrib = nxelement.attrib
        xml_type = nxelement.parse_type()
        if xml_type == 'LiteralMeta':
            value = attrib.get("content", None)
            key = attrib.get("property", None)
            annotate_as_reference = False
        else:
            value = attrib.get("href", None)
            key = attrib.get("rel", None)
            annotate_as_reference = True
        datatype_hint = attrib.get("datatype", None)
        if key is None:
            raise ValueError("Could not determine property/rel for meta element: %s\n%s" % (nxelement, attrib))
        name_prefix, name = textprocessing.parse_curie_standard_qualified_name(key)
        try:
            namespace = self._namespace_registry.prefix_namespace_map[name_prefix]
        except KeyError:
            raise ValueError("CURIE-standard prefix '%s' not defined in document: %s" % (name_prefix, self._namespace_registry))
        if datatype_hint is not None:
            dt_prefix, dt = textprocessing.parse_curie_standard_qualified_name(datatype_hint)
            if dt_prefix is not None:
                try:
                    dt_namespace = self._namespace_registry.prefix_namespace_map[dt_prefix]
                except KeyError:
                    raise ValueError("CURIE-standard prefix '%s' not defined in document: %s" % (dt_prefix, self._namespace_registry))
                if dt_namespace.startswith("http://www.w3.org/2001/XMLSchema"):
                    value = self._coerce_to_xml_schema_type(value, dt)
                elif dt_namespace.startswith("http://www.nexml.org/1.0") or dt_namespace.startswith("http://www.nexml.org/2009"):
                    value = self._coerce_to_nexml_type(value, dt)
                elif dt_namespace.startswith("http://dendropy.org") or dt_namespace.startswith("http://packages.python.org/DendroPy"):
                    value = self._coerce_to_dendropy_type(value, dt)
        a = annotated.annotations.add_new(
                name=name,
                value=value,
                datatype_hint=datatype_hint,
                name_prefix=name_prefix,
                namespace=namespace,
                name_is_prefixed=False,
                annotate_as_reference=annotate_as_reference)
        top_annotations = [i for i in nxelement.findall_annotations()]
        for annotation in top_annotations:
            self._parse_annotations(a, annotation)

    def _coerce_to_xml_schema_type(self, value, type_name):
        if type_name in ("boolean"):
            if value.lower() in ("1", "t", "true", "y", "yes",):
                return True
            else:
                return False
        elif type_name in ("decimal", "float", "double"):
            coerce_type = float
        elif type_name in ("byte", "int", "integer", "long", "negativeInteger", "nonNegativeInteger", "nonPositiveInteger", "short", "unsignedInt", "unsignedLong", "unsignedShort"):
            coerce_type = int
        else:
            return value
        return self._coerce_type(value, coerce_type)

    def _coerce_to_dendropy_type(self, value, type_name):
        if type_name in ("decimalRange"):
            try:
                value = [float(v) for v in value.split()]
            except KeyError:
                pass
        return value

    def _coerce_to_nexml_type(self, value, type_name):
        if type_name in ("ContinuousSeq"):
            try:
                value = [float(v) for v in value.split()]
            except KeyError:
                pass
        return value

    def _coerce_type(self, value, to_type):
        try:
            value = to_type(value)
        except ValueError:
            pass
        return value


class NexmlElement(xmlprocessing.XmlElement):

    def __init__(self, element, default_namespace=None):
        # if default_namespace is None:
        #     default_namespace = NexmlReader.DEFAULT_NEXML_NAMESPACE
        # else:
        #     default_namespace = default_namespace
        xmlprocessing.XmlElement.__init__(self,
                element=element,
                default_namespace=default_namespace)
        self.type_parse_pattern = re.compile(r"([A-Za-z0-9]+?):(.+)")

    ## Annotations ##

    def findall_annotations(self):
        return self.namespaced_findall("meta")

    ## TaxonSet Elements ##

    def iter_otus(self):
        return self.namespaced_getiterator("otus")

    def findall_otu(self):
        return self.namespaced_findall("otu")

    ## Characters ##

    def iter_characters(self):
        return self.namespaced_getiterator("characters")

    def find_char_format(self):
        return self.namespaced_find("format")

    def find_char_matrix(self):
        return self.namespaced_find("matrix")

    def findall_multistate_member(self):
        return self.namespaced_findall("member")

    def findall_polymorphic_state_set(self):
        return self.namespaced_findall("polymorphic_state_set")

    def findall_uncertain_state_set(self):
        return self.namespaced_findall("uncertain_state_set")

    def findall_char_state(self):
        return self.namespaced_findall("state")

    def findall_char_states(self):
        return self.namespaced_findall("states")

    def findall_char(self):
        return self.namespaced_findall("char")

    def findall_char_row(self):
        return self.namespaced_findall("row")

    def findall_char_cell(self):
        return self.namespaced_findall("cell")

    def find_char_seq(self):
        return self.namespaced_findtext("seq")

    ## Trees ##

    def iter_trees(self):
        return self.namespaced_getiterator("trees")

    def findall_tree(self):
        return self.namespaced_findall("tree")

    def findall_node(self):
        return self.namespaced_findall("node")

    def findall_edge(self):
        return self.namespaced_findall("edge")

    def find_rootedge(self):
        return self.namespaced_find("rootedge")

    def parse_type(self):
        type_value = self._element.get('{http://www.w3.org/2001/XMLSchema-instance}type', None)
        if type_value is None:
            raise ValueError("Type not specified for element '%s'" % self._element.get("id", None))
        m = self.type_parse_pattern.match(type_value)
        if m:
            return m.groups()[1]
        else:
            return type_value

class NexmlReader(ioservice.DataReader, _AnnotationParser):
    "Implements thinterface for handling NEXML files."

    ###########################################################################
    ## Life-cycle and Setup

    DEFAULT_NEXML_NAMESPACE = "http://www.nexml.org/2009"

    def __init__(self, **kwargs):
        """
        Keyword Arguments
        -----------------

        default_namespace : str
            Default namespace to use for elements.
        case_sensitive_taxon_labels: boolean, default: |False|
            If |True|, then case is respected when matching taxon names.
            Default is |False|: case is ignored.
        ignore_unrecognized_keyword_arguments : boolean, default: |False|
            If |True|, then unsupported or unrecognized keyword arguments will
            not result in an error. Default is |False|: unsupported keyword
            arguments will result in an error.

        """
        _AnnotationParser.__init__(self)
        ioservice.DataReader.__init__(self)
        self.default_namespace = kwargs.pop("default_namespace", NexmlReader.DEFAULT_NEXML_NAMESPACE)
        self.case_sensitive_taxon_labels = kwargs.pop('case_sensitive_taxon_labels', False)

        ### NOTE: following are not actually supported.
        ### They are here because some tests automatically add include them on calls.
        ### TODO: remove these keywords from generic tests
        self.suppress_internal_node_taxa = kwargs.pop("suppress_internal_node_taxa", True)
        self.suppress_leaf_node_taxa = kwargs.pop("suppress_external_node_taxa", False) # legacy (will be deprecated)
        self.suppress_leaf_node_taxa = kwargs.pop("suppress_leaf_node_taxa", self.suppress_leaf_node_taxa)
        self.data_type = kwargs.pop("data_type", None)

        self.check_for_unused_keyword_arguments(kwargs)

        # Set up parsing meta-variables
        self._id_taxon_namespace_map = {}
        self._id_taxon_map = {}
        self._taxon_namespace_factory = None
        self._tree_list_factory = None
        self._char_matrix_factory = None
        self._state_alphabet_factory = None
        self._global_annotations_target = None
        self._taxon_namespaces = []
        self._char_matrices = []
        self._tree_lists = []
        self._product = None

    ###########################################################################
    ## Reader Interface

    def _read(self,
            stream,
            taxon_namespace_factory=None,
            tree_list_factory=None,
            char_matrix_factory=None,
            state_alphabet_factory=None,
            global_annotations_target=None):
        xml_doc = xmlprocessing.XmlDocument(file_obj=stream,
                subelement_factory=self._subelement_factory)
        self._namespace_registry = xml_doc.namespace_registry
        self._taxon_namespace_factory = taxon_namespace_factory
        self._tree_list_factory = tree_list_factory
        self._char_matrix_factory = char_matrix_factory
        self._state_alphabet_factory = state_alphabet_factory
        self._global_annotations_target = global_annotations_target
        self._parse_document(xml_doc)
        self._product = self.Product(
                taxon_namespaces=self._taxon_namespaces,
                tree_lists=self._tree_lists,
                char_matrices=self._char_matrices)
        return self._product

    ###########################################################################
    ## Support

    def _subelement_factory(self, element):
        return NexmlElement(element, default_namespace=self.default_namespace)

    ###########################################################################
    ## Data Management

    def _new_taxon_namespace(self, label=None):
        if self.attached_taxon_namespace is not None:
            return self.attached_taxon_namespace
        taxon_namespace = self._taxon_namespace_factory(label=label)
        self._taxon_namespaces.append(taxon_namespace)
        return taxon_namespace

    def _new_char_matrix(self, data_type, taxon_namespace, label=None, **kwargs):
        char_matrix = self._char_matrix_factory(
                data_type,
                taxon_namespace=taxon_namespace,
                label=label,
                **kwargs)
        self._char_matrices.append(char_matrix)
        return char_matrix

    def _new_state_alphabet(self, *args, **kwargs):
        return self._state_alphabet_factory(*args, **kwargs)

    def _new_tree_list(self, taxon_namespace, label=None):
        tree_list = self._tree_list_factory(
                taxon_namespace=taxon_namespace,
                label=label)
        self._tree_lists.append(tree_list)
        return tree_list

    ###########################################################################
    ## Parsers

    ## Following methods are class-specific ###

    def _parse_document(self, xml_doc):
        xml_root = xml_doc.root
        self._parse_taxon_namespaces(xml_root)
        if self._char_matrix_factory is not None:
            self._parse_char_matrices(xml_root)
        if self._tree_list_factory is not None:
            self._parse_tree_lists(xml_root)
        if self._global_annotations_target is not None:
            top_annotations = [i for i in xml_root.findall_annotations()]
            for annotation in top_annotations:
                self._parse_annotations(self._global_annotations_target, annotation)

    def _parse_taxon_namespaces(self, xml_root):
        for nxtaxa in xml_root.iter_otus():
            taxon_namespace_label = nxtaxa.get('label', None)
            taxon_namespace = self._new_taxon_namespace(label=taxon_namespace_label)
            taxon_namespace_id = nxtaxa.get('id', id(taxon_namespace))
            self._id_taxon_namespace_map[taxon_namespace_id] = taxon_namespace
            annotations = [i for i in nxtaxa.findall_annotations()]
            for annotation in annotations:
                self._parse_annotations(taxon_namespace, annotation)
            if self.case_sensitive_taxon_labels:
                label_taxon_map = {}
            else:
                label_taxon_map = container.OrderedCaselessDict()
            if self.attached_taxon_namespace is not None:
                for t in taxon_namespace:
                    label_taxon_map[t.label] = t
            for idx, nxtaxon in enumerate(nxtaxa.findall_otu()):
                taxon = None
                taxon_label = nxtaxon.get('label', None)
                taxon_oid = nxtaxon.get('id', id(nxtaxon))
                if taxon_label is not None and self.attached_taxon_namespace is not None:
                    # taxon = label_taxon_map.get_taxon(
                    #         label=taxon_label,
                    #         case_sensitive=self.case_sensitive_taxon_labels)
                    try:
                        taxon = label_taxon_map[taxon_label]
                    except KeyError:
                        taxon = None
                if taxon is None:
                    taxon = taxon_namespace.new_taxon(label=taxon_label)
                annotations = [i for i in nxtaxon.findall_annotations()]
                for annotation in annotations:
                    self._parse_annotations(taxon, annotation)
                self._id_taxon_map[(taxon_namespace_id, taxon_oid)] = taxon

    def _parse_char_matrices(self, xml_root):
        nxc = _NexmlCharBlockParser(self._namespace_registry,
                self._id_taxon_namespace_map,
                self._id_taxon_map,
                self._new_char_matrix,
                self._state_alphabet_factory)
        for char_matrix_element in xml_root.iter_characters():
            nxc.parse_char_matrix(char_matrix_element)

    def _parse_tree_lists(self, xml_root):
        for trees_idx, trees_element in enumerate(xml_root.iter_trees()):
            self._parse_tree_list(trees_element, trees_idx, True)

    def _parse_tree_list(self, nxtrees, trees_idx=None, add_to_tree_list=True):
        trees_id = nxtrees.get('id', "Trees" + str(trees_idx))
        trees_label = nxtrees.get('label', None)
        otus_id = nxtrees.get('otus', None)
        if otus_id is None:
            raise Exception("Taxa block not specified for trees block '{}'".format(otus_id))
        taxon_namespace = self._id_taxon_namespace_map.get(otus_id, None)
        if not taxon_namespace:
            raise Exception("Tree block '{}': Taxa block '{}' not found".format(trees_id, otus_id))
        tree_list = self._new_tree_list(
                label=trees_label,
                taxon_namespace=taxon_namespace)
        annotations = [i for i in nxtrees.findall_annotations()]
        for annotation in annotations:
            self._parse_annotations(tree_list, annotation)
        tree_parser = _NexmlTreeParser(
                id_taxon_map=self._id_taxon_map,
                annotations_processor_fn=self._parse_annotations,
                )
        for tree_element in nxtrees.findall_tree():
            tree_obj = tree_list.new_tree()
            tree_parser.build_tree(tree_obj, tree_element, otus_id)

class _NexmlTreeParser(object):

    EdgeInfo = collections.namedtuple(
            "EdgeInfo",
            ["edge_id", "label", "tail_node_id", "head_node_id", "length", "annotations"]
            )

    def __init__(self,
            id_taxon_map,
            annotations_processor_fn,
            ):
        self._id_taxon_map = id_taxon_map
        self._process_annotations = annotations_processor_fn

    def build_tree(self, tree_obj, tree_element, otus_id):
        tree_obj.label = tree_element.get('label', '')
        tree_type_attr = tree_element.get('{http://www.w3.org/2001/XMLSchema-instance}type')
        tree_obj.length_type = _from_nexml_tree_length_type(tree_type_attr)
        tree_obj.is_rooted = False # default unless explicitly set
        annotations = [i for i in tree_element.findall_annotations()]
        for annotation in annotations:
            self._process_annotations(tree_obj, annotation)
        unparented_node_set, node_id_map, root_node_list = self._parse_nodes(
                tree_element,
                tree_obj.node_factory,
                otus_id)
        if len(root_node_list) > 1:
            raise Exception("Multiple root nodes defined but the DendroPy tree model currently only supported single-root trees")
        elif len(root_node_list) == 1:
            tree_obj.seed_node = root_node_list[0]
            tree_obj.is_rooted = True
        edges_info = self._parse_edges_info(tree_element, length_type=tree_obj.length_type)
        for edge_info in edges_info:
            if edge_info.head_node_id is None:
                raise Exception("Edge '{}' does not specify a head (target) node".format(edge_info.edge_id, edge_info.head_node_id))
            try:
                head_node = node_id_map[edge_info.head_node_id]
            except KeyError:
                raise Exception("Edge '{}' specifies a non-defined head (target) node '{}'".format(edge_info.edge_id, edge_info.head_node_id))
            if edge_info.tail_node_id is not None:
                try:
                    tail_node = node_id_map[edge_info.tail_node_id]
                except KeyError:
                    raise Exception("Edge '{}' specifies a non-defined tail (source) node '{}'".format(edge_info.edge_id, edge_info.tail_node_id))
                head_node.parent_node = tail_node
                assert head_node.edge.tail_node is tail_node
                unparented_node_set.remove(head_node)
            else:
                assert head_node.parent_node is None
            self._set_edge_details(head_node.edge, edge_info)

        # find node(s) without parent
        # unparented_node_sets = []
        # for node in nodes.values():
        #     if node.parent_node == None:
        #         unparented_node_sets.append(node)

        # If one unparented_node_sets node found, this is the root: we use
        # it as the tree head node. If multiple unparented_node_sets nodes
        # are found, then we add them all as child_nodes of the
        # existing head node. If none, then we have some sort of
        # cyclicity, and we are not dealing with a tree.
        if len(unparented_node_set) == 1:
            unparented_node = unparented_node_set.pop()
            if root_node_list:
                if root_node_list[0] is not unparented_node:
                    raise Exception("Tree already has an explictly defined root node, but node without parent found: {}".format(unparented_node))
            else:
                tree_obj.seed_node = unparented_node
        elif len(unparented_node_sets) > 1:
            for node in unparented_node_set:
                tree_obj.seed_node.add_child(node)
        else:
            raise Exception("Structural error: tree must be acyclic.")

        root_edge_element = tree_element.find_rootedge()
        if root_edge_element is not None:
            root_edge_info = self._parse_edge_info(root_edge_element, tree_obj.length_type)
            root_node = node_id_map[root_edge_info.head_node_id]
            if root_node is not tree_obj.seed_node:
                raise Exception("Root edge does not subtend root node")
            root_edge = root_node.edge
            self._set_edge_details(root_edge, root_edge_info)
            # tree_obj.is_rooted = True

        return tree_obj

    def _parse_nodes(self, tree_element, node_factory, otus_id):
        """
        Given an XmlElement representation of a NEXML tree element,
        (`nex:tree`) this will return a dictionary of DendroPy Node
        objects with the node_id as the key.
        """
        node_set = set()
        node_id_map = {}
        root_node_list = []
        for nxnode in tree_element.findall_node():
            node_id = nxnode.get('id', None)
            node = node_factory()
            node_id_map[node_id] = node
            node_set.add(node)
            node_id_map[node_id].label = nxnode.get('label', None)
            taxon_id = nxnode.get('otu', None)
            if taxon_id is not None:
                try:
                    taxon = self._id_taxon_map[(otus_id, taxon_id)]
                except KeyError:
                    raise Exception("Taxon with id '{}' not defined '{}'".format(taxon_id, otus_id))
                node_id_map[node_id].taxon = taxon
            annotations = [i for i in nxnode.findall_annotations()]
            for annotation in annotations:
                self._process_annotations(node_id_map[node_id], annotation)
            rooting_state = nxnode.get('root', None)
            if rooting_state is not None and rooting_state.lower() in ("1", "t", "true"):
                root_node_list.append(node)
        return node_set, node_id_map, root_node_list

    def _parse_edges_info(self, tree_element, length_type):
        edges_info = []
        for nxedge in tree_element.findall_edge():
            edges_info.append(self._parse_edge_info(nxedge, length_type))
        return edges_info

    def _parse_edge_info(self, nxedge, length_type):
        edge_id = nxedge.get('id', None)
        edge_label = nxedge.get('label', None)
        tail_node_id = nxedge.get('source', None)
        # assert tail_node_id is not None
        head_node_id = nxedge.get('target', None)
        # assert head_node_id is not None
        edge_length_str = nxedge.get('length', 0.0)
        edge_length = None
        try:
            edge_length = length_type(edge_length_str)
        except ValueError:
            msg = "Edge {} 'length' attribute is not of type {}: '{}'".format(
                    edge_id, str(length_type), edge_length_str)
            raise Exception(msg)
        annotations = [i for i in nxedge.findall_annotations()]
        e = _NexmlTreeParser.EdgeInfo(
                edge_id=edge_id,
                label=edge_label,
                tail_node_id=tail_node_id,
                head_node_id=head_node_id,
                length=edge_length,
                annotations=annotations)
        return e

    def _set_edge_details(self, edge, edge_info):
        edge.length = edge_info.length
        edge.label = edge_info.label
        for annotation in edge_info.annotations:
            self._process_annotations(edge, annotation)

class _NexmlCharBlockParser(_AnnotationParser):
    "Parses an XmlElement representation of NEXML taxa blocks."

    def __init__(self,
            namespace_registry,
            id_taxon_namespace_map,
            id_taxon_map,
            char_matrix_factory,
            state_alphabet_factory,
            ):
        _AnnotationParser.__init__(self, namespace_registry)
        self._id_taxon_namespace_map = id_taxon_namespace_map
        self._id_taxon_map = id_taxon_map
        self._char_matrix_factory = char_matrix_factory
        self._state_alphabet_factory = state_alphabet_factory

        self._id_state_alphabet_map = {}
        self._id_state_map = {}
        self._id_chartype_map = {}
        self._char_types = []
        self._chartype_id_to_pos_map = {}

    def parse_char_matrix(self, nxchars):
        """
        Given an XmlElement representing a nexml characters block, this
        instantiates and returns a corresponding DendroPy CharacterMatrix object.
        """

        # clear
        self._id_state_alphabet_map = {}
        self._id_state_map = {}
        self._id_chartype_map = {}
        self._char_types = []
        self._chartype_id_to_pos_map = {}

        # initiaiize
        label = nxchars.get('label', None)
        char_matrix_oid = nxchars.get('oid', '')

        # set up taxa
        otus_id = nxchars.get('otus', None)
        if otus_id is None:
            raise Exception("Character Block %s (\"%s\"): Taxon namespace not specified" % (char_matrix_oid, char_matrix.label))
        taxon_namespace = self._id_taxon_namespace_map.get(otus_id, None)
        if not taxon_namespace:
            raise Exception("Character Block %s (\"%s\"): Specified taxon namespace not found" % (char_matrix_oid, char_matrix.label))

        # character matrix instantiation
        nxchartype = nxchars.parse_type()
        extra_kwargs = {}
        if nxchartype.startswith('Dna'):
            data_type = "dna"
        elif nxchartype.startswith('Rna'):
            data_type = "rna"
        elif nxchartype.startswith('Protein'):
            data_type = "protein"
        elif nxchartype.startswith('Restriction'):
            data_type = "restriction"
        elif nxchartype.startswith('Standard'):
            data_type = "standard"
            extra_kwargs["default_state_alphabet"] = None
        elif nxchartype.startswith('Continuous'):
            data_type = "continuous"
        else:
            raise Exception("Character Block %s (\"%s\"): Character type '%s' not supported" % (char_matrix_oid, char_matrix.label, nxchartype))
        char_matrix = self._char_matrix_factory(
                data_type,
                taxon_namespace=taxon_namespace,
                label=label,
                **extra_kwargs)

        # annotation processing
        annotations = [i for i in nxchars.findall_annotations()]
        for annotation in annotations:
            self._parse_annotations(char_matrix, annotation)

        # get state mappings
        nxformat = nxchars.find_char_format()
        if nxformat is not None:
            self.parse_characters_format(nxformat, data_type, char_matrix)
        elif data_type == "standard":
            self.create_standard_character_alphabet(char_matrix)

        nxmatrix = nxchars.find_char_matrix()
        annotations = [i for i in nxmatrix.findall_annotations()]
        for annotation in annotations:
            self._parse_annotations(char_matrix.taxon_seq_map, annotation)
        for nxrow in nxmatrix.findall_char_row():
            row_id = nxrow.get('id', None)
            label = nxrow.get('label', None)
            taxon_id = nxrow.get('otu', None)
            try:
                taxon = self._id_taxon_map[(otus_id, taxon_id)]
            except KeyError:
                raise error.DataParseError(message='Character Block %s (\"%s\"): Taxon with id "%s" not defined in taxa block "%s"' % (char_matrix.oid, char_matrix.label, taxon_id, otus_id))

            character_vector = char_matrix.new_sequence(taxon=taxon)
            annotations = [i for i in nxrow.findall_annotations()]
            for annotation in annotations:
                self._parse_annotations(character_vector, annotation)

            if data_type == "continuous":
                if nxchartype.endswith('Seqs'):
                    seq = nxrow.find_char_seq()
                    if seq is not None:
                        seq = seq.replace('\n\r', ' ').replace('\r\n', ' ').replace('\n', ' ').replace('\r',' ')
                        col_idx = -1
                        for char in seq.split(' '):
                            char = char.strip()
                            if char:
                                col_idx += 1
                                if len(self._char_types) <= col_idx:
                                    raise error.DataParseError(message="Character column/type ('<char>') not defined for character in position"\
                                        + " %d (matrix = '%s' row='%s', taxon='%s')" % (col_idx+1, char_matrix.oid, row_id, taxon.label))
                                character_vector.append(character_value=float(char), character_type=self._char_types[col_idx])
                else:
                    for nxcell in nxrow.findall_char_cell():
                        chartype_id = nxcell.get('char', None)
                        if chartype_id is None:
                            raise error.DataParseError(message="'char' attribute missing for cell: cell markup must indicate character column type for character"\
                                        + " (matrix = '%s' row='%s', taxon='%s')" % (char_matrix.oid, row_id, taxon.label))
                        if chartype_id not in self._id_chartype_map:
                            raise error.DataParseError(message="Character type ('<char>') with id '%s' referenced but not found for character" % chartype_id \
                                        + " (matrix = '%s' row='%s', taxon='%s')" % (char_matrix.oid, row_id, taxon.label))
                        chartype = self._id_chartype_map[chartype_id]
                        pos_idx = self._char_types.index(chartype)
#                         column = id_chartype_map[chartype_id]
#                         state = column.state_id_map[cell.get('state', None)]
                        # annotations = [i for i in nxcell.findall_annotations]
                        # for annotation in annotations:
                        #     self._parse_annotations(cell, annotation)
                        character_vector.append(character_value=float(nxcell.get('state')),
                                character_type=chartype)
            else:
                if nxchartype.endswith('Seqs'):
                    seq = nxrow.find_char_seq()
                    if seq is not None:
                        seq = seq.replace(' ', '').replace('\n', '').replace('\r', '')
                        col_idx = -1
                        for char in seq:
                            col_idx += 1
                            state_alphabet = char_matrix.character_types[col_idx].state_alphabet
                            try:
                                state = state_alphabet[char]
                            except KeyError:
                                raise error.DataParseError(message="Character Block row '%s', character position %s: State with symbol '%s' in sequence '%s' not defined" \
                                        % (row_id, col_idx, char, seq))
                            if len(self._char_types) <= col_idx:
                                raise error.DataParseError(message="Character column/type ('<char>') not defined for character in position"\
                                    + " %d (row='%s', taxon='%s')" % (col_idx+1, row_id, taxon.label))
                            character_type = self._char_types[col_idx]
                            character_vector.append(character_value=state,
                                    character_type=character_type)
                else:
                    for nxcell in nxrow.findall_char_cell():
                        chartype_id = nxcell.get('char', None)
                        if chartype_id is None:
                            raise error.DataParseError(message="'char' attribute missing for cell: cell markup must indicate character column type for character"\
                                        + " (matrix = '%s' row='%s', taxon='%s')" % (char_matrix_oid, row_id, taxon.label))
                        if chartype_id not in self._id_chartype_map:
                            raise error.DataParseError(message="Character type ('<char>') with id '%s' referenced but not found for character" % chartype_id \
                                        + " (matrix = '%s' row='%s', taxon='%s')" % (char_matrix_oid, row_id, taxon.label))
                        chartype = self._id_chartype_map[chartype_id]
                        state_alphabet = self._id_chartype_map[chartype_id].state_alphabet
                        pos_idx = self._chartype_id_to_pos_map[chartype_id]
                        state = self._id_state_map[ (state_alphabet, nxcell.get('state', None)) ]
                        character_vector.set_at(pos_idx,
                                character_value=state,
                                character_type=chartype)
                        # self._id_state_alphabet_map = {}
                        # self._id_state_map = {}
                        # self._id_chartype_map = {}

            char_matrix[taxon] = character_vector

        # if fixed_state_alphabet:
        #     char_matrix.remap_to_default_state_alphabet_by_symbol(purge_other_state_alphabets=True)

    def parse_ambiguous_state(self, nxstate, state_alphabet):
        """
        Parses an XmlElement represent an ambiguous discrete character state,
        ("uncertain_state_set")
        and returns a corresponding StateAlphabetElement object.
        """
        state_oid = nxstate.get('id', None)
        state_symbol = nxstate.get('symbol', None)
        token = nxstate.get('token', None)
        member_states = []
        for nxmember in nxstate.findall_multistate_member():
            member_state_id = nxmember.get('state', None)
            member_state = self._id_state_map[ (state_alphabet, member_state_id) ]
            member_states.append(member_state)
        state = state_alphabet.new_multistate(symbol=state_symbol,
                state_denomination=state_alphabet.AMBIGUOUS_STATE,
                member_states=member_states)
        assert (state_alphabet, state_oid) not in self._id_state_map
        self._id_state_map[ (state_alphabet, state_oid) ] = state
        if token is not None:
            state_alphabet.new_symbol_synonym(token, state_symbol)
        return state

    def parse_polymorphic_state(self, nxstate, state_alphabet):
        """
        Parses an XmlElement represent a polymorphic discrete character state,
        ("polymorphic_state_set")
        and returns a corresponding StateAlphabetElement object.
        """
        state_oid = nxstate.get('id', None)
        state_symbol = nxstate.get('symbol', None)
        token = nxstate.get('token', None)
        member_states = []
        for nxmember in nxstate.findall_multistate_member():
            member_state_id = nxmember.get('state', None)
            member_state = self._id_state_map[ (state_alphabet, member_state_id) ]
            member_states.append(member_state)
        for nxambiguous in nxstate.findall_uncertain_state_set():
            member_states.append(self.parse_ambiguous_state(nxstate, state_alphabet))
        state = state_alphabet.new_multistate(symbol=state_symbol,
                state_denomination=state_alphabet.POLYMORPHIC_STATE,
                member_states=member_states)
        assert (state_alphabet, state_oid) not in self._id_state_map
        self._id_state_map[ (state_alphabet, state_oid) ] = state
        if token is not None:
            state_alphabet.new_symbol_synonym(token, state_symbol)
        return state

    def parse_state_alphabet(self, nxstates):
        """
        Given an XmlElement representing a nexml definition of (discrete or standard) states
        ("states"), this returns a corresponding StateAlphabet object.
        """
        state_alphabet_oid = nxstates.get("id", None)
        state_alphabet = self._state_alphabet_factory()
        state_alphabet.autocompile_lookup_tables = False
        self._id_state_alphabet_map[state_alphabet_oid] = state_alphabet
        for nxstate in nxstates.findall_char_state():
            state_oid = nxstate.get('id', None)
            state_symbol = nxstate.get('symbol', None)
            state = state_alphabet.new_fundamental_state(symbol=state_symbol)
            token = nxstate.get('token', None)
            assert (state_alphabet, state_oid) not in self._id_state_map
            self._id_state_map[ (state_alphabet, state_oid) ] = state
            if token is not None:
                state_alphabet.new_symbol_synonym(token, state_symbol)
        for nxstate in nxstates.findall_uncertain_state_set():
            self.parse_ambiguous_state(nxstate, state_alphabet)
        for nxstate in nxstates.findall_polymorphic_state_set():
            self.parse_polymorphic_state(nxstate, state_alphabet)
        state_alphabet.autocompile_lookup_tables = True
        state_alphabet.compile_lookup_mappings()
        return state_alphabet

    def parse_characters_format(self, nxformat, data_type, char_matrix):
        """
        Given an XmlElement schema element ("format"), this parses the
        state definitions (if any) and characters (column definitions, if any),
        and populates the given char_matrix accordingly.
        """
        # if data_type == "standard":
        #     for nxstates in nxformat.findall_char_states():
        #         char_matrix.state_alphabets.append(self.parse_state_alphabet(nxstates))
        # else:
        #     pass
        if data_type in ("dna", "rna", "protein", "restriction"):
            # fixed alphabet: map to existing states
            for nxstates in nxformat.findall_char_states():
                state_alphabet_oid = nxstates.get("id", None)
                if state_alphabet_oid is not None:
                    self._id_state_alphabet_map[state_alphabet_oid] = char_matrix.default_state_alphabet
                for nxstate in nxstates.findall_char_state():
                    state_oid = nxstate.get('id', None)
                    label = nxstate.get('label', None)
                    symbol = nxstate.get('symbol', None)
                    token = nxstate.get('token', None)
                    try:
                        state = char_matrix.default_state_alphabet[symbol]
                    except KeyError:
                        raise Exception("'{}' is not a recognized symbol for the state alphabet for the '{}' data type".format(symbol, data_type))
                    assert (char_matrix.default_state_alphabet, state_oid) not in self._id_state_map
                    self._id_state_map[ (char_matrix.default_state_alphabet, state_oid) ] = state
                for nxstate in nxstates.findall_polymorphic_state_set():
                    state_oid = nxstate.get('id', None)
                    symbol = nxstate.get('symbol', None)
                    try:
                        state = char_matrix.default_state_alphabet[symbol]
                    except KeyError:
                        raise Exception("'{}' is not a recognized symbol for the state alphabet for the '{}' data type".format(symbol, data_type))
                    assert (char_matrix.default_state_alphabet, state_oid) not in self._id_state_map
                    self._id_state_map[ (char_matrix.default_state_alphabet, state_oid) ] = state
                for nxstate in nxstates.findall_uncertain_state_set():
                    state_oid = nxstate.get('id', None)
                    symbol = nxstate.get('symbol', None)
                    try:
                        state = char_matrix.default_state_alphabet[symbol]
                    except KeyError:
                        raise Exception("'{}' is not a recognized symbol for the state alphabet for the '{}' data type".format(symbol, data_type))
                    assert (char_matrix.default_state_alphabet, state_oid) not in self._id_state_map
                    self._id_state_map[ (char_matrix.default_state_alphabet, state_oid) ] = state
        else:
            for nxstates in nxformat.findall_char_states():
                char_matrix.state_alphabets.append(self.parse_state_alphabet(nxstates))
        for nxchars in nxformat.findall_char():
            col = char_matrix.new_character_type()
            char_state_set_id = nxchars.get('states')
            if char_state_set_id is not None:
                state_alphabet = self._id_state_alphabet_map.get(char_state_set_id, None)
                if state_alphabet is None:
                    raise Exception("State set '%s' not defined" % char_state_set_id)
                col.state_alphabet = state_alphabet
            elif hasattr(char_matrix, "default_state_alphabet") \
                and char_matrix.default_state_alphabet is not None:
                col.state_alphabet = char_matrix.default_state_alphabet
            char_matrix.character_types.append(col)
            chartype_id = nxchars.get('id')
            self._chartype_id_to_pos_map[chartype_id] = len(self._chartype_id_to_pos_map)
            self._id_chartype_map[chartype_id] = col
            self._char_types.append(col)

    def create_standard_character_alphabet(self, char_matrix, symbol_list=None):
        """
        Returns a standard character state alphabet based on symbol_list.
        Defaults to '0' - '9' if not specified.
        """
        if symbol_list is None:
            symbol_list = [str(i) for i in xrange(10)]
        state_alphabet = dendropy.StateAlphabet()
        for s in symbol_list:
            state_alphabet.append(dendropy.StateAlphabetElement(symbol=s))
        char_matrix.state_alphabets.append(state_alphabet)
        char_matrix.default_state_alphabet = state_alphabet