# cython: profile=True
# coding: utf8
from spacy.errors import user_warning

cdef class KnowledgeBase:

    def __init__(self):
        self._entry_index = PreshMap()
        self._alias_index = PreshMap()
        self.mem = Pool()
        self.strings = StringStore()
        self.create_empty_vectors()

    def __len__(self):
        return self.get_size_entities()

    def get_size_entities(self):
        return self._entries.size() - 1  # not counting dummy element on index 0

    def get_size_aliases(self):
        return self._aliases_table.size() - 1 # not counting dummy element on index 0

    def add_entity(self, unicode entity_id, float prob, vectors=None, features=None):
        cdef hash_t id_hash = self.strings.add(entity_id)

        # Return if this entity was added before
        if id_hash in self._entry_index:
            user_warning("Entity " + entity_id + " already exists in the KB")
            return

        cdef int32_t dummy_value = 342
        self.c_add_entity(entity_key=id_hash, prob=prob, vector_rows=&dummy_value, feats_row=dummy_value)
        # TODO self._vectors_table.get_pointer(vectors),
        # self._features_table.get(features))

    def add_alias(self, unicode alias, entities, probabilities):
        """For a given alias, add its potential entities and prior probabilies to the KB."""

        # Throw an error if the probabilities sum up to more than 1
        prob_sum = sum(probabilities)
        if prob_sum > 1:
            raise ValueError("The sum of prior probabilities for alias '" + alias + "' should not exceed 1, "
                                                                                    "but found " + str(prob_sum))

        cdef hash_t alias_hash = self.strings.add(alias)

        # Return if this alias was added before
        if alias_hash in self._alias_index:
            user_warning("Alias " + alias + " already exists in the KB")
            return

        cdef hash_t entity_hash

        cdef vector[int64_t] entry_indices
        cdef vector[float] probs

        for entity, prob in zip(entities, probabilities):
            entity_hash = self.strings[entity]
            if not entity_hash in self._entry_index:
                raise ValueError("Alias '" + alias + "' defined for unknown entity '" + entity + "'")

            entry_index = <int64_t>self._entry_index.get(entity_hash)
            entry_indices.push_back(int(entry_index))
            probs.push_back(float(prob))

        # TODO: check sum(probabilities) <= 1
        # TODO: check len(entities) == len(probabilities)

        self.c_add_aliases(alias_key=alias_hash, entry_indices=entry_indices, probs=probs)


    def get_candidates(self, unicode alias):
        cdef hash_t alias_hash = self.strings.add(alias)
        alias_index = <int64_t>self._alias_index.get(alias_hash)
        return self._aliases_table[alias_index]