"""
also see https://github.com/w3c/N3/tree/master/tests/N3Tests
"""
from collections import defaultdict
from decimal import Decimal
from typing import cast
import unittest

from rdflib import RDF, BNode, ConjunctiveGraph, Graph, Literal, Namespace
from rdflib.graph import ReadOnlyGraphAggregate
from rdflib.parser import StringInputSource

from inference import Inference, Lhs
from rdflib_debug_patches import patchBnodeCounter, patchSlimReprs

patchSlimReprs()
patchBnodeCounter()

EX = Namespace('http://example.com/')
ROOM = Namespace('http://projects.bigasterisk.com/room/')


def N3(txt: str):
    g = ConjunctiveGraph()
    prefix = """
@prefix : <http://example.com/> .
@prefix room: <http://projects.bigasterisk.com/room/> .
@prefix math: <http://www.w3.org/2000/10/swap/math#> .
"""
    g.parse(StringInputSource((prefix + txt).encode('utf8')), format='n3')
    return g


def makeInferenceWithRules(n3):
    inf = Inference()
    inf.setRules(N3(n3))
    return inf


class WithGraphEqual(unittest.TestCase):

    def assertGraphEqual(self, g: Graph, expected: Graph):
        stmts1 = list(g.triples((None, None, None)))
        stmts2 = list(expected.triples((None, None, None)))
        self.assertCountEqual(stmts1, stmts2)


class TestInferenceWithoutVars(WithGraphEqual):

    def testEmitNothing(self):
        inf = makeInferenceWithRules("")
        implied = inf.infer(N3(":a :b :c ."))
        self.assertEqual(len(implied), 0)

    def testSimple(self):
        inf = makeInferenceWithRules("{ :a :b :c . } => { :a :b :new . } .")
        implied = inf.infer(N3(":a :b :c ."))
        self.assertGraphEqual(implied, N3(":a :b :new ."))

    def testTwoRounds(self):
        inf = makeInferenceWithRules("""
        { :a :b :c . } => { :a :b :new1 . } .
        { :a :b :new1 . } => { :a :b :new2 . } .
        """)

        implied = inf.infer(N3(":a :b :c ."))
        self.assertGraphEqual(implied, N3(":a :b :new1, :new2 ."))


class TestInferenceWithVars(WithGraphEqual):

    def testVarInSubject(self):
        inf = makeInferenceWithRules("{ ?x :b :c . } => { :new :stmt ?x } .")
        implied = inf.infer(N3(":a :b :c ."))
        self.assertGraphEqual(implied, N3(":new :stmt :a ."))

    def testVarInObject(self):
        inf = makeInferenceWithRules("{ :a :b ?x . } => { :new :stmt ?x } .")
        implied = inf.infer(N3(":a :b :c ."))
        self.assertGraphEqual(implied, N3(":new :stmt :c ."))

    def testVarMatchesTwice(self):
        inf = makeInferenceWithRules("{ :a :b ?x . } => { :new :stmt ?x } .")
        implied = inf.infer(N3(":a :b :c, :d ."))
        self.assertGraphEqual(implied, N3(":new :stmt :c, :d ."))

    def testTwoRulesApplyIndependently(self):
        inf = makeInferenceWithRules("""
            { :a :b ?x . } => { :new :stmt ?x . } .
            { :d :e ?y . } => { :new :stmt2 ?y . } .
            """)
        implied = inf.infer(N3(":a :b :c ."))
        self.assertGraphEqual(implied, N3("""
            :new :stmt :c .
            """))
        implied = inf.infer(N3(":a :b :c . :d :e :f ."))
        self.assertGraphEqual(implied, N3("""
            :new :stmt :c .
            :new :stmt2 :f .
            """))

    def testOneRuleActivatesAnother(self):
        inf = makeInferenceWithRules("""
            { :a :b ?x . } => { :new :stmt ?x . } .
            { ?y :stmt ?z . } => { :new :stmt2 ?y . } .
            """)
        implied = inf.infer(N3(":a :b :c ."))
        self.assertGraphEqual(implied, N3("""
            :new :stmt :c .
            :new :stmt2 :new .
            """))

    def testVarLinksTwoStatements(self):
        inf = makeInferenceWithRules("{ :a :b ?x . :d :e ?x } => { :new :stmt ?x } .")
        implied = inf.infer(N3(":a :b :c  ."))
        self.assertGraphEqual(implied, N3(""))
        implied = inf.infer(N3(":a :b :c . :d :e :f ."))
        self.assertGraphEqual(implied, N3(""))
        implied = inf.infer(N3(":a :b :c . :d :e :c ."))
        self.assertGraphEqual(implied, N3(":new :stmt :c ."))

    def testRuleMatchesStaticStatement(self):
        inf = makeInferenceWithRules("{ :a :b ?x . :a :b :c . } => { :new :stmt ?x } .")
        implied = inf.infer(N3(":a :b :c  ."))
        self.assertGraphEqual(implied, N3(":new :stmt :c ."))


class TestBnodeMatching(WithGraphEqual):

    def testRuleBnodeBindsToInputBnode(self):
        inf = makeInferenceWithRules("{ [ :a :b ] . } => { :new :stmt :here } .")
        implied = inf.infer(N3("[ :a :b ] ."))
        self.assertGraphEqual(implied, N3(":new :stmt :here ."))

    def testRuleVarBindsToInputBNode(self):
        inf = makeInferenceWithRules("{ ?z :a :b  . } => { :new :stmt :here } .")
        implied = inf.infer(N3("[] :a :b ."))
        self.assertGraphEqual(implied, N3(":new :stmt :here ."))


class TestSelfFulfillingRule(WithGraphEqual):

    def test1(self):
        inf = makeInferenceWithRules("{ } => { :new :stmt :x } .")
        self.assertGraphEqual(inf.infer(N3("")), N3(":new :stmt :x ."))
        self.assertGraphEqual(inf.infer(N3(":any :any :any .")), N3(":new :stmt :x ."))

    def test2(self):
        inf = makeInferenceWithRules("{ (2) math:sum ?x } => { :new :stmt ?x } .")
        self.assertGraphEqual(inf.infer(N3("")), N3(":new :stmt 2 ."))

    @unittest.skip("too hard for now")
    def test3(self):
        inf = makeInferenceWithRules("{ :a :b :c . :a :b ?x . } => { :new :stmt ?x } .")
        self.assertGraphEqual(inf.infer(N3("")), N3(":new :stmt :c ."))


class TestInferenceWithMathFunctions(WithGraphEqual):

    def testBoolFilter(self):
        inf = makeInferenceWithRules("{ :a :b ?x . ?x math:greaterThan 5 } => { :new :stmt ?x } .")
        self.assertGraphEqual(inf.infer(N3(":a :b 3 .")), N3(""))
        self.assertGraphEqual(inf.infer(N3(":a :b 5 .")), N3(""))
        self.assertGraphEqual(inf.infer(N3(":a :b 6 .")), N3(":new :stmt 6 ."))

    def testNonFiringMathRule(self):
        inf = makeInferenceWithRules("{ :a :b ?x . (?x 1) math:sum ?y } => { :new :stmt ?y } .")
        self.assertGraphEqual(inf.infer(N3("")), N3(""))

    def testStatementGeneratingRule(self):
        inf = makeInferenceWithRules("{ :a :b ?x . (?x 1) math:sum ?y } => { :new :stmt ?y } .")
        self.assertGraphEqual(inf.infer(N3(":a :b 3 .")), N3(":new :stmt 4 ."))

    def test3Operands(self):
        inf = makeInferenceWithRules("{ :a :b ?x . (2 ?x 2) math:sum ?y } => { :new :stmt ?y } .")
        self.assertGraphEqual(inf.infer(N3(":a :b 2 .")), N3(":new :stmt 6 ."))

    def test0Operands(self):
        inf = makeInferenceWithRules("{ :a :b ?x . () math:sum ?y } => { :new :stmt ?y } .")
        self.assertGraphEqual(inf.infer(N3(":a :b 2 .")), N3(":new :stmt 0 ."))


class TestInferenceWithCustomFunctions(WithGraphEqual):

    def testAsFarenheit(self):
        inf = makeInferenceWithRules("{ :a :b ?x . ?x room:asFarenheit ?f } => { :new :stmt ?f } .")
        self.assertGraphEqual(inf.infer(N3(":a :b 12 .")), N3(":new :stmt 53.6 ."))


class TestUseCases(WithGraphEqual):

    def testSimpleTopic(self):
        inf = makeInferenceWithRules('''
            { ?msg :body "online" . } => { ?msg :onlineTerm :Online . } .
            { ?msg :body "offline" . } => { ?msg :onlineTerm :Offline . } .

            {
            ?msg a :MqttMessage ;
                :topic :foo;
                :onlineTerm ?onlineness . } => {
            :frontDoorLockStatus :connectedStatus ?onlineness .
            } .
        ''')

        out = inf.infer(N3('[] a :MqttMessage ; :body "online" ; :topic :foo .'))
        self.assertIn((EX['frontDoorLockStatus'], EX['connectedStatus'], EX['Online']), out)

    @unittest.skip("still too slow")
    def testTopicIsList(self):
        inf = makeInferenceWithRules('''
            { ?msg :body "online" . } => { ?msg :onlineTerm :Online . } .
            { ?msg :body "offline" . } => { ?msg :onlineTerm :Offline . } .

            {
            ?msg a :MqttMessage ;
                :topic ( "frontdoorlock" "status" );
                :onlineTerm ?onlineness . } => {
            :frontDoorLockStatus :connectedStatus ?onlineness .
            } .
        ''')

        out = inf.infer(N3('[] a :MqttMessage ; :body "online" ; :topic ( "frontdoorlock" "status" ) .'))
        self.assertIn((EX['frontDoorLockStatus'], EX['connectedStatus'], EX['Online']), out)

    def testPerformance0(self):
        inf = makeInferenceWithRules('''
            {
              ?msg a :MqttMessage;
                :topic :topic1;
                :bodyFloat ?valueC .
              ?valueC math:greaterThan -999 .
              ?valueC room:asFarenheit ?valueF .
            } => {
              :airQualityIndoorTemperature :temperatureF ?valueF .
            } .
        ''')
        out = inf.infer(
            N3('''
            <urn:uuid:c6e1d92c-0ee1-11ec-bdbd-2a42c4691e9a> a :MqttMessage ;
                :body "23.9" ;
                :bodyFloat 2.39e+01 ;
                :topic :topic1 .
            '''))

        vlit = cast(Literal, out.value(EX['airQualityIndoorTemperature'], EX['temperatureF']))
        valueF = cast(Decimal, vlit.toPython())
        self.assertAlmostEqual(float(valueF), 75.02)

    @unittest.skip("still too slow")
    def testPerformance1(self):
        inf = makeInferenceWithRules('''
            {
              ?msg a :MqttMessage;
                :topic ( "air_quality_indoor" "sensor" "bme280_temperature" "state" );
                :bodyFloat ?valueC .
              ?valueC math:greaterThan -999 .
              ?valueC :asFarenheit ?valueF .
            } => {
              :airQualityIndoorTemperature :temperatureF ?valueF .
            } .
        ''')
        out = inf.infer(
            N3('''
            <urn:uuid:c6e1d92c-0ee1-11ec-bdbd-2a42c4691e9a> a :MqttMessage ;
                :body "23.9" ;
                :bodyFloat 2.39e+01 ;
                :topic ( "air_quality_indoor" "sensor" "bme280_temperature" "state" ) .
        '''))
        vlit = cast(Literal, out.value(EX['airQualityIndoorTemperature'], EX['temperatureF']))
        valueF = cast(Decimal, vlit.toPython())
        self.assertAlmostEqual(float(valueF), 75.02)


class TestListPerformance(WithGraphEqual):

    def testList1(self):
        inf = makeInferenceWithRules("{ :a :b (:e0) . } => { :new :stmt :here } .")
        implied = inf.infer(N3(":a :b (:e0) ."))
        self.assertGraphEqual(implied, N3(":new :stmt :here ."))

    def testList2(self):
        inf = makeInferenceWithRules("{ :a :b (:e0 :e1) . } => { :new :stmt :here } .")
        implied = inf.infer(N3(":a :b (:e0 :e1) ."))
        self.assertGraphEqual(implied, N3(":new :stmt :here ."))

    def testList3(self):
        inf = makeInferenceWithRules("{ :a :b (:e0 :e1 :e2) . } => { :new :stmt :here } .")
        implied = inf.infer(N3(":a :b (:e0 :e1 :e2) ."))
        self.assertGraphEqual(implied, N3(":new :stmt :here ."))

    @unittest.skip("still too slow")
    def testList4(self):
        inf = makeInferenceWithRules("{ :a :b (:e0 :e1 :e2 :e3) . } => { :new :stmt :here } .")
        implied = inf.infer(N3(":a :b (:e0 :e1 :e2 :e3) ."))
        self.assertGraphEqual(implied, N3(":new :stmt :here ."))


def fakeStats():
    return defaultdict(lambda: 0)

class TestLhsFindCandidateBindings(WithGraphEqual):

    def testBnodeMatchesStmt(self):
        l = Lhs(N3("[] :a :b ."))
        ws = ReadOnlyGraphAggregate([N3("[] :a :b .")])
        cands = list(l.findCandidateBindings(ws, fakeStats()))
        self.assertEqual(len(cands), 1)

    def testVarMatchesStmt(self):
        l = Lhs(N3("?x :a :b ."))
        ws = ReadOnlyGraphAggregate([N3("[] :a :b .")])
        cands = list(l.findCandidateBindings(ws, fakeStats()))
        self.assertEqual(len(cands), 1)

    @unittest.skip("still too slow")
    def testListsOnlyMatchEachOther(self):
        l = Lhs(N3(":a :b (:e0 :e1) ."))
        ws = ReadOnlyGraphAggregate([N3(":a :b (:e0 :e1) .")])
        stats = fakeStats()
        cands = list(l.findCandidateBindings(ws, stats))
        self.assertLess(stats['permCountFailingVerify'], 20)
        self.fail(str(cands))