# standard imports
import unittest

# bsie imports
from bsie.utils import bsfs, ns

# objects to test
from bsie.extractor import base


## code ##

class StubExtractor(base.Extractor):
    def __init__(self):
        super().__init__(bsfs.schema.from_string(base.SCHEMA_PREAMBLE + '''
            bse:author rdfs:subClassOf bsfs:Predicate ;
                rdfs:domain bsn:Entity ;
                rdfs:range xsd:string ;
                bsfs:unique "false"^^xsd:boolean .
            bse:comment rdfs:subClassOf bsfs:Predicate ;
                rdfs:domain bsn:Entity ;
                rdfs:range xsd:string ;
                bsfs:unique "false"^^xsd:boolean .
        '''))

    def extract(self, subject, content, predicates):
        raise NotImplementedError()

class StubSub(StubExtractor):
    pass

class TestExtractor(unittest.TestCase):
    def test_essentials(self):
        ext = StubExtractor()
        self.assertEqual(str(ext), 'StubExtractor')
        self.assertEqual(repr(ext), 'StubExtractor()')
        self.assertEqual(ext, StubExtractor())
        self.assertEqual(hash(ext), hash(StubExtractor()))

        sub = StubSub()
        self.assertEqual(str(sub), 'StubSub')
        self.assertEqual(repr(sub), 'StubSub()')
        self.assertEqual(sub, StubSub())
        self.assertEqual(hash(sub), hash(StubSub()))
        self.assertNotEqual(ext, sub)
        self.assertNotEqual(hash(ext), hash(sub))

    def test_principals(self):
        schema = bsfs.schema.Schema()
        entity = schema.node(ns.bsfs.Node).child(ns.bsn.Entity)
        string = schema.literal(ns.bsfs.Literal).child(ns.xsd.string)
        p_author = schema.predicate(ns.bsfs.Predicate).child(ns.bse.author, domain=entity, range=string)
        p_comment = schema.predicate(ns.bsfs.Predicate).child(ns.bse.comment, domain=entity, range=string)
        ext = StubExtractor()
        self.assertSetEqual(set(ext.principals),
            {p_author, p_comment} | set(schema.predicates()) - {schema.predicate(ns.bsfs.Predicate)})


## main ##

if __name__ == '__main__':
    unittest.main()

## EOF ##