# -*- coding: utf-8 -*-

from django.core.management import BaseCommand

from django.db import reset_queries, transaction

from optparse import make_option

from p4l.models import Record, Language

from p4l.utils import show_progress

from rdflib import Graph, Namespace, BNode, URIRef

from rdflib.plugins.sparql import prepareQuery

import logging

import xml.etree.cElementTree as ET

logger = logging.getLogger(__name__)

RDF = Namespace("http://www.w3.org/1999/02/22-rdf-syntax-ns#")

RDFS = Namespace("http://www.w3.org/2000/01/rdf-schema#")

DCT = Namespace("http://purl.org/dc/terms/")

IIEP = Namespace("http://www.iiep.unesco.org/plan4learning/model.owl#")

UNESCO = Namespace("http://www.iiep.unesco.org/Ontology/")

DEFAULT_LANGUAGE_URI = "http://psi.oasis-open.org/iso/639/#eng"

DEFAULT_LANGUAGE_QUERY =  """SELECT ( COALESCE(?lang, ?other_lang) as ?main_lang) WHERE {

    OPTIONAL { ?s dct:language ?lang }.

    OPTIONAL { ?s iiep:otherLanguage ?other_lang }.

}"""

class Command(BaseCommand):

    args = "record_url ..."

    help = "Import p4l record rdf format"

    option_list = BaseCommand.option_list + (

        make_option('-b', '--batch-size',

            dest= 'batch_size',

            type='int',

            default= 50,

            help= 'number of object to import in bulk operations' 

        ),

    )

    def __init__(self, *args, **kwargs):

        super(Command, self).__init__(*args, **kwargs)

        self.__query_cache = {}

    def __get_sparql_query(self, query, namespaces):

        return self.__query_cache[query] \

            if query in self.__query_cache \

            else self.__query_cache.setdefault(query, prepareQuery(query, initNs=namespaces))

    def get_empty_graph(self):

        record_graph = Graph()

        record_graph.bind('iiep',"http://www.iiep.unesco.org/plan4learning/model.owl#")

        record_graph.bind('dct',"http://purl.org/dc/terms/")

        return record_graph

    def extract_single_value_form_graph(self, graph, q, bindings={}, index=0, convert=lambda v:unicode(v) if v is not None else None):

        return next(self.extract_multiple_values_from_graph(graph, q, bindings, index, convert), None)

    def extract_multiple_values_from_graph(self, graph, q, bindings={}, index=0, convert=lambda v:unicode(v) if v is not None else None):

        index_list = index

        if isinstance(index, int):

            index_list = range(index+1)

        if hasattr(convert, '__call__'):

            convert_dict = dict((k, convert) for k in index_list)

        else:

            convert_dict = convert

        convert_dict = dict((k, f if hasattr(f,'__call__') else lambda v:unicode(v) if v is not None else None) for k,f in convert_dict.iteritems())

        for row in graph.query(self.__get_sparql_query(q, dict(graph.namespaces())), initBindings=bindings):

            if len(row) < len(index_list):

                break

            else:

                res = dict([ (k, convert_dict.get(k, lambda v:unicode(v) if v is not None else None)(v)) for k, v in zip(index_list, row)])

                if isinstance(index, int):

                    yield res[index]

                else:

                    yield res

    def convert_bool(self, val):

        if val == True or val == False:

            return val

        if val is None:

            return False

        if isinstance(val, basestring):

            if len(val) == 0:

                return False

            if val[0].lower() in ['t','y','1','o']:

                return True

            else:

                return False        

        return bool(val)

    def add_to_related_collection(self, coll, graph, fields, q, bindings={},  convert=lambda v: unicode(v) if v is not None else None, through_fields=None):

        for val in self.extract_multiple_values_from_graph(graph, q, bindings=bindings, index=fields, convert=convert):

            if through_fields:                

                new_obj_val = dict([(k,v) for k,v in val.iteritems() if k not in through_fields])

            else:

                new_obj_val = val

            if hasattr(coll, 'through'):

                new_obj_rel, _ = coll.model.objects.get_or_create(**new_obj_val)

                if through_fields:

                    through_vals = {coll.source_field_name: coll.instance, coll.target_field_name: new_obj_rel}

                    through_vals.update(dict([(k,v) for k,v in val.iteritems() if k in through_fields]))

                    coll.through.objects.create(**through_vals)

                    new_obj = None

                else:

                    new_obj = new_obj_rel

            else:

                new_obj = coll.create(**new_obj_val)

            if new_obj:

                coll.add(new_obj)

    def build_record(self, graph):

        record_uri = self.extract_single_value_form_graph(graph,"SELECT DISTINCT ?s WHERE { ?s rdf:type iiep:Record .}")

        record = Record()

        record.uri = record_uri

        record.identifier = self.extract_single_value_form_graph(graph,"SELECT DISTINCT ?o WHERE { ?s dct:identifier ?o .}", bindings={'s':URIRef(record.uri)})

        record.notes = self.extract_single_value_form_graph(graph,"SELECT DISTINCT ?o WHERE { ?s iiep:notes ?o .}", bindings={'s':URIRef(record.uri)})

        record.recordType = self.extract_single_value_form_graph(graph,"SELECT DISTINCT ?o WHERE { ?s dct:type ?o .}", bindings={'s':URIRef(record.uri)})

        record.isDocumentPart = self.extract_single_value_form_graph(graph,"SELECT DISTINCT ?o WHERE { ?s iiep:isDocumentPart ?o .}", bindings={'s':URIRef(record.uri)}, convert=self.convert_bool)

        record.editionStatement = self.extract_single_value_form_graph(graph,"SELECT DISTINCT ?o WHERE { ?s iiep:editionStatement ?o .}", bindings={'s':URIRef(record.uri)})

        language = self.extract_single_value_form_graph(graph,"SELECT DISTINCT ?o WHERE { ?s dct:language ?o .}", bindings={'s':URIRef(record.uri)})

        if language:

        record.save()

        self.add_to_related_collection(record.authors, graph, ['name'], "SELECT ?o WHERE { ?s iiep:author ?o .}", bindings={'s':URIRef(record.uri)})

        self.add_to_related_collection(record.subjectPersons, graph, ['name'], "SELECT ?o WHERE { ?s iiep:subjectPerson ?o .}", bindings={'s':URIRef(record.uri)})

        self.add_to_related_collection(

            record.periodicals,

            graph, 

            ['label','lang'],

            "SELECT DISTINCT ?o  ( lang(?o) as ?l) WHERE { ?s iiep:periodical ?o .}",

            bindings={'s':URIRef(record.uri)},

            through_fields = ['lang']

        )

        self.add_to_related_collection(

            record.meetings,

            graph, 

            ['label', 'meetingNumber', 'meetingPlace', 'meetingDate', 'meetingYear', 'lang'],

            "SELECT ?l ?mn ?mp ?md ?my (lang(COALESCE(?l,?nm, ?mp,?md,?my)) as ?lang) WHERE { [iiep:meeting ?bnode]. OPTIONAL { ?bnode rdfs:label ?l }. OPTIONAL { ?bnode iiep:meetingNumber ?mn }. OPTIONAL { ?bnode iiep:meetingPlace ?mp }.  OPTIONAL { ?bnode iiep:meetingDate ?md }. OPTIONAL { ?bnode iiep:meetingYear ?my }}",

            convert={'meetingYear' : lambda y: int(y) if y is not None else None},

            through_fields = ['lang']

        )

        self.add_to_related_collection(

            record.series,

            graph, 

            ['title', 'volume', 'lang'],

            "SELECT ?t ?vol (lang(COALESCE(?t,?vol)) as ?lang) WHERE { [iiep:serie ?bnode]. OPTIONAL { ?bnode dct:title ?t }. OPTIONAL { ?bnode iiep:volume ?vol } }",

            through_fields = ['lang']

        )

        self.add_to_related_collection(

            record.subjectCorporateBodies,

            graph,

        )

        self.add_to_related_collection(

            record.subjectMeetings,

            graph,

            ['label', 'meetingNumber', 'meetingPlace', 'meetingDate', 'meetingYear'],

            "SELECT ?l ?mn ?mp ?md ?my WHERE { [iiep:subjectMeeting ?bnode]. OPTIONAL { ?bnode rdfs:label ?l }. OPTIONAL { ?bnode iiep:meetingNumber ?mn }. OPTIONAL { ?bnode iiep:meetingPlace ?mp }.  OPTIONAL { ?bnode iiep:meetingDate ?md }. OPTIONAL { ?bnode iiep:meetingYear ?my }}",            

            convert={'meetingYear' : lambda y: int(y) if y is not None else None}

        )

        self.add_to_related_collection(

            record.corporateAuthors,

            graph,

        )

        self.add_to_related_collection(

            record.issns,

            graph,

            ['issn', 'lang'],

            "SELECT ?issn (lang(COALESCE(?issn)) as ?lang) WHERE { ?s iiep:issn ?issn . }",

            bindings={'s':URIRef(record.uri)},

        )

        self.add_to_related_collection(

            record.isbns,

            graph,

            ['isbn', 'lang'],

            "SELECT ?isbn (lang(COALESCE(?isbn)) as ?lang) WHERE { ?s iiep:isbn ?isbn . }",

            bindings={'s':URIRef(record.uri)},

        )

        self.add_to_related_collection(

            record.documentCodes,

            graph,

            ['documentCode', 'lang'],

            "SELECT ?c (lang(COALESCE(?c)) as ?lang) WHERE { ?s iiep:documentCode ?c . }",

            bindings={'s':URIRef(record.uri)},

        )

        self.add_to_related_collection(

            record.titles,

            graph,

            ['title', 'lang'],

            "SELECT ?t (lang(COALESCE(?t)) as ?lang) WHERE { ?s dct:title ?t . }",

            bindings={'s':URIRef(record.uri)},

        )

        self.add_to_related_collection(

            record.abstracts,

            graph,

            ['abstract', 'lang'],

            "SELECT ?t (lang(COALESCE(?t)) as ?lang) WHERE { ?s dct:abstract ?t . }",

            bindings={'s':URIRef(record.uri)},

        )

        self.add_to_related_collection(

            record.addedTitles,

            graph,

            ['title', 'lang'],

            "SELECT ?t (lang(COALESCE(?t)) as ?lang) WHERE { ?s iiep:addedTitle ?t . }",

            bindings={'s':URIRef(record.uri)},

        )

        self.add_to_related_collection(

            record.titlesMainDocument,

            graph,

            ['title', 'lang'],

            "SELECT ?t (lang(COALESCE(?t)) as ?lang) WHERE { ?s iiep:titleMainDocument ?t . }",

            bindings={'s':URIRef(record.uri)},

        )

        self.add_to_related_collection(

            record.imprints,

            graph,

            ['imprintCity', 'publisher', 'imprintDate', 'lang'],

            "SELECT ?c ?p ?d (lang(COALESCE(?c, ?p, ?d)) as ?lang) WHERE { [ iiep:imprint ?bnode ]. OPTIONAL { ?bnode iiep:imprintCity ?c }. OPTIONAL { ?bnode dct:publisher ?p }. OPTIONAL { ?bnode iiep:imprintDate ?d }}",

        )

        self.add_to_related_collection(

            record.collations,

            graph,

            ['collation', 'lang'],

            "SELECT ?c (lang(COALESCE(?c)) as ?lang) WHERE { ?s iiep:collation ?c . }",

            bindings={'s':URIRef(record.uri)},

        )

        self.add_to_related_collection(

            record.volumeIssues,

            graph,

            ['volume', 'number', 'lang'],

            "SELECT ?v ?n (lang(COALESCE(?v, ?n)) as ?lang) WHERE { [ iiep:volumeIssue ?bnode ]. OPTIONAL { ?bnode iiep:volume ?v }. OPTIONAL { ?bnode iiep:number ?n }}",

        )

        self.add_to_related_collection(

            record.urls,

            graph,

            ['address', 'display', 'accessLevel'],

            "SELECT ?a ?d ?al WHERE { [ iiep:url ?bnode ]. OPTIONAL { ?bnode iiep:address ?a }. OPTIONAL { ?bnode iiep:display ?d }. OPTIONAL { ?bnode iiep:accessLevel ?al }.}",

        )

        return record

    def filter_node(self, node, graph, res_graph):

        for p,o in graph[node]:

            res_graph.add((node,p,o))

            if isinstance(o, BNode):

                self.filter_node(o, graph, res_graph)

    def calculate_records_nb(self, records_url):

        context = ET.iterparse(records_url, events=("end",))

        i = 0

        for _,elem in context:

            if elem.tag == "{%s}Record" % IIEP:

                i += 1

        return i

    def process_url(self, records_url, options):

        total_records = self.calculate_records_nb(records_url)

        writer = None

        errors=[]

        context = ET.iterparse(records_url, events=("end",))

        i = 0

        for _,elem in context:

            if elem.tag == "{%s}Record" % IIEP:

                i += 1

                writer = show_progress(i, total_records, "Processing record nb %d " % i, 50, writer=writer)

                try:

                    record_graph = self.get_empty_graph()

                    record_graph.parse(data=ET.tostring(elem, encoding='utf-8'), format='xml')

                    # add transaction management

                    self.build_record(record_graph)                    

                except Exception as e:

                    transaction.rollback()

                    msg = "Error processing resource %d in %s : %s" % (i, records_url, repr(e))

                    logger.exception(msg)

                    errors.append((i, records_url, msg))

                else:

                    transaction.commit()

                if i%self.batch_size == 0:                    

                    reset_queries()

        return errors

    # def process_url(self, records_url, options):

    #     #open graph with rdflib

    #             

    #     g = Graph()

    #     print("Loading %s" % records_url)

    #     g.parse(records_url)

    #     print("Parsing %s done" % records_url)

    #     for i,record_uri in enumerate(g[:RDF.type:IIEP.Record]):

    #         print(i, repr(record_uri))

    #         record_graph = self.get_empty_graph()

    #         self.filter_node(record_uri, g, record_graph)

    #         self.build_record(record_graph)

    #         if i > 3:

    #             break

    def handle(self, *args, **options):

        self.batch_size = options.get('batch_size', 50)

        transaction.enter_transaction_management()

        transaction.managed(True)

        for records_url in args:

            print("Processing %s" % records_url)

            errors = self.process_url(records_url, options)

            print("Processing %s Done" % records_url)

            if errors:

                print("%d error(s) when processing %s, check your log file." % (len(errors), records_url))

        transaction.leave_transaction_management()