from sfa.util.sfatime import utcparse, datetime_to_string
from datetime import datetime
from sfa.util.xml import XML
from sfa.trust.gid import GID

from sfa.util.sfalogging import logger


class Record:

    def __init__(self, dict=None, xml_str=None):
        if dict:
            self.load_from_dict(dict)
        elif xml_str:
            xml = XML(xml_str)
            xml_dict = xml.todict()
            self.load_from_dict(xml_dict)

    def get_field(self, field):
        return self.__dict__.get(field, None)

    # xxx fixme
    # turns out the date_created field is received by the client as a 'created' int
    # (and 'last_updated' does not make it at all)
    # let's be flexible
    def date_repr(self, fields):
        if not isinstance(fields, list):
            fields = [fields]
        for field in fields:
            value = getattr(self, field, None)
            if isinstance(value, datetime):
                return datetime_to_string(value)
            elif isinstance(value, (int, float)):
                return datetime_to_string(utcparse(value))
        # fallback
        return "** undef_datetime **"

    #
    # need to filter out results, esp. wrt relationships
    # exclude_types must be a tuple so we can use isinstance
    #
    def record_to_dict(self, exclude_types=None):
        if exclude_types is None:
            exclude_types = ()
        d = self.__dict__

        def exclude(k, v):
            return k.startswith('_') or isinstance(v, exclude_types)
        keys = [k for k, v in list(d.items()) if not exclude(k, v)]
        return {k: d[k] for k in keys}

    def toxml(self):
        return self.save_as_xml()

    def load_from_dict(self, d):
        for (k, v) in d.items():
            # experimental
            if isinstance(v, str) and v.lower() in ['true']:
                v = True
            if isinstance(v, str) and v.lower() in ['false']:
                v = False
            setattr(self, k, v)

    # in addition we provide convenience for converting to and from xml records
    # for this purpose only, we need the subclasses to define 'fields' as either
    # a list or a dictionary
    def fields(self):
        fields = list(self.__dict__.keys())
        return fields

    def save_as_xml(self):
        # xxx not sure about the scope here
        input_dict = dict([(key, getattr(self, key))
                           for key in self.fields() if getattr(self, key, None)])
        xml_record = XML("<record />")
        xml_record.parse_dict(input_dict)
        return xml_record.toxml()

    def dump(self, format=None, dump_parents=False, sort=False):
        if not format:
            format = 'text'
        else:
            format = format.lower()
        if format == 'text':
            self.dump_text(dump_parents, sort=sort)
        elif format == 'xml':
            print(self.save_as_xml())
        elif format == 'simple':
            print(self.dump_simple())
        else:
            raise Exception("Invalid format %s" % format)

    def dump_text(self, dump_parents=False, sort=False):
        print(40 * '=')
        print("RECORD")
        # print remaining fields
        fields = self.fields()
        if sort:
            fields.sort()
        for attrib_name in fields:
            attrib = getattr(self, attrib_name)
            # skip internals
            if attrib_name.startswith('_'):
                continue
            # skip callables
            if callable(attrib):
                continue
            # handle gid
            if attrib_name == 'gid':
                print("    gid:")
                print(GID(string=attrib).dump_string(8, dump_parents))
            elif attrib_name in ['date created', 'last updated']:
                print("    %s: %s" % (attrib_name, self.date_repr(attrib_name)))
            else:
                print("    %s: %s" % (attrib_name, attrib))

    def dump_simple(self):
        return "%s" % self