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"""
File: /graph.py
Created Date: Sunday October 19th 2025
Author: Christian Nonis <alch.infoemail@gmail.com>
-----
Last Modified: Monday February 2nd 2026 10:02:37 pm
Modified By: Christian Nonis <alch.infoemail@gmail.com>
-----
"""

import re
from abc import ABC, abstractmethod
from typing import Dict, List, Literal, Optional, Tuple
from src.adapters.interfaces.graph import GraphClient, PredicateWithFlowKey
from src.constants.embeddings import Vector
from src.constants.kg import (
    IdentificationParams,
    Node,
    NodeDict,
    Predicate,
    PredicateDict,
    SearchEntitiesResult,
    SearchRelationshipsResult,
)
from src.adapters.interfaces.embeddings import VectorStoreClient
from src.adapters.graph_operation_result_serializer import (
    serialize_graph_operation_result,
)
from src.core.search.traverse import (
    MAX_TRAVERSE_DEPTH,
    MAX_TRAVERSE_HOPS,
    flatten_neighborhood,
)
from src.utils.normalization.list_reduction import reduce_list
from src.utils.similarity.vectors import cosine_similarity


class NeighborVectorReductionStrategy(ABC):
    @abstractmethod
    def prefilter(
        self,
        vectors_with_desc: list[dict],
        averaged_vector: list[float],
        description: Optional[str],
    ) -> list[dict]:
        raise NotImplementedError


class SimilarityOnlyReductionStrategy(NeighborVectorReductionStrategy):
    def prefilter(
        self,
        vectors_with_desc: list[dict],
        averaged_vector: list[float],
        description: Optional[str],
    ) -> list[dict]:
        return vectors_with_desc


class DescriptionAwareReductionStrategy(NeighborVectorReductionStrategy):
    def prefilter(
        self,
        vectors_with_desc: list[dict],
        averaged_vector: list[float],
        description: Optional[str],
    ) -> list[dict]:
        if not description:
            return vectors_with_desc
        return reduce_list(
            vectors_with_desc,
            access_key="embeddings",
            similarity_threshold=0.8,
            by_vector=averaged_vector,
            rerank={
                "local": "description",
                "with_": description,
            },
        )


class NeighborVectorReductionStrategyFactory:
    def create(self, description: Optional[str]) -> NeighborVectorReductionStrategy:
        if description:
            return DescriptionAwareReductionStrategy()
        return SimilarityOnlyReductionStrategy()


class GraphAdapter:
    """
    Adapter for the graph client.
    """

    def __init__(
        self, reduction_strategy_factory: Optional[NeighborVectorReductionStrategyFactory] = None
    ):
        self.graph = None
        self._reduction_strategy_factory = (
            reduction_strategy_factory or NeighborVectorReductionStrategyFactory()
        )

    @property
    def graphdb_type(self) -> str:
        """
        This is the type of the graph database.
        It is used to let the agent know which syntax to use.
        """
        return self.graph.graphdb_type

    @property
    def graphdb_description(self) -> str:
        """
        This is the description of the graph database.
        It is used to let the agent know which syntax to use.
        """
        return self.graph.graphdb_description

    def add_client(self, client: GraphClient) -> None:
        """
        Add a graph client to the adapter.
        """
        self.graph = client

    def execute_operation(self, operation: str, brain_id: str = "default") -> str:
        """
        Execute a generic graph operation.
        """
        try:
            result = self.graph.execute_operation(operation, brain_id)
            return serialize_graph_operation_result(result)
        except Exception as e:  # pylint: disable=broad-exception-caught
            hint = ""
            backend = getattr(self.graph, "graphdb_type", "") or ""
            if "postgresql" in backend and re.search(
                r"\bMATCH\b|\bRETURN\b|\bFROM\s+nodes\b", operation or "", re.I
            ):
                hint = (
                    " Hint: this backend expects SQL on kg_nodes/kg_relationships, "
                    "not Cypher and not a table named nodes."
                )
            print(f"Error executing graph operation: {e} - {operation}")
            return f"Error executing graph operation: {e}.{hint}"

    def add_nodes(
        self,
        nodes: list[Node],
        brain_id: str = "default",
        identification_params: Optional[dict] = None,
        metadata: Optional[dict] = None,
    ) -> list[Node] | str:
        """
        Add nodes to the graph.
        """
        return self.graph.add_nodes(nodes, brain_id, identification_params, metadata)

    def add_relationship(
        self,
        subject: Node,
        predicate: Predicate,
        to_object: Node,
        brain_id: str = "default",
    ) -> str:
        """
        Add a relationship between two nodes to the graph.
        """
        return self.graph.add_relationship(subject, predicate, to_object, brain_id)

    def search_graph(
        self,
        nodes: list[Node],
        brain_id: str = "default",
    ) -> list[Node]:
        """
        Search the graph for nodes and 1 degree relationships.
        """
        return self.graph.search_graph(nodes, brain_id)

    def node_text_search(self, text: str, brain_id: str = "default") -> list[Node]:
        """
        Search the graph for nodes by partial text match into the name of the nodes.
        """
        return self.graph.node_text_search(text, brain_id)

    def get_nodes_by_uuid(
        self,
        uuids: list[str],
        brain_id: str = "default",
        with_relationships: Optional[bool] = False,
        relationships_depth: Optional[int] = 1,
        relationships_type: Optional[list[str]] = None,
        preferred_labels: Optional[list[str]] = None,
    ) -> list[dict]:
        """
        Get nodes by their UUIDs with optional relationships and preferred labels.
        """
        return self.graph.get_nodes_by_uuid(
            uuids,
            brain_id,
            with_relationships,
            relationships_depth,
            relationships_type,
            preferred_labels,
        )

    def get_graph_entities(self, brain_id: str = "default") -> list[str]:
        """
        Get the entities of the graph.
        """
        return self.graph.get_graph_entities(brain_id)

    def get_graph_relationships(self, brain_id: str = "default") -> list[str]:
        """
        Retrieve relationship type names available in the graph.

        Parameters:
            brain_id (str): Identifier of the graph/brain to query.

        Returns:
            list[str]: Relationship type names present in the specified graph.
        """
        return self.graph.get_graph_relationships(brain_id)

    def get_by_uuid(self, uuid: str, brain_id: str = "default") -> Node:
        """
        Retrieve a node by its UUID from the graph.

        Deprecated: use `get_by_uuids` for batch retrieval.

        Parameters:
            uuid (str): UUID of the node to retrieve.
            brain_id (str): Identifier of the graph/brain to query.

        Returns:
            Node: The node matching the provided UUID.
        """
        return self.graph.get_by_uuid(uuid, brain_id)

    def get_by_uuids(self, uuids: list[str], brain_id: str = "default") -> list[Node]:
        """
        Get nodes by their UUIDs.
        """
        return self.graph.get_by_uuids(uuids, brain_id)

    def get_by_identification_params(
        self,
        identification_params: IdentificationParams,
        brain_id: str = "default",
        entity_types: Optional[list[str]] = None,
    ) -> Node:
        """
        Get a node by its identification params and entity types.
        """
        return self.graph.get_by_identification_params(
            identification_params, brain_id, entity_types
        )

    def get_neighbors(
        self,
        nodes: list[Node | str],
        same_type_only: bool = False,
        limit: int | None = None,
        of_types: Optional[list[str]] = None,
        brain_id: str = "default",
    ) -> Dict[str, List[Tuple[Predicate, Node]]]:
        """
        Get the neighbors of a node.
        """
        return self.graph.get_neighbors(
            nodes,
            brain_id=brain_id,
            same_type_only=same_type_only,
            limit=limit,
            of_types=of_types,
        )

    def get_event_centric_neighbors(
        self,
        nodes: list[Node | str],
        brain_id: str = "default",
    ) -> List[Tuple[Node, Predicate, Node, Predicate, Node]]:
        """
        Get the event-centric neighbors of a node.
        """
        return self.graph.get_event_centric_neighbors(nodes, brain_id)

    def get_node_with_rel_by_uuid(
        self, rel_ids_with_node_ids: list[tuple[str, str]], brain_id: str = "default"
    ) -> list[dict]:
        """
        Get the node with the relationships by their UUIDs.
        """
        return self.graph.get_node_with_rel_by_uuid(rel_ids_with_node_ids, brain_id)

    def get_neighbor_node_tuples(
        self, a_uuid: str, b_uuids: list[str], brain_id: str = "default"
    ) -> list[Tuple[Node, Predicate, Node]]:
        """
        Get the neighbor node tuples by their UUIDs.
        """
        return self.graph.get_neighbor_node_tuples(a_uuid, b_uuids, brain_id)

    def get_connected_nodes(
        self,
        brain_id: str = "default",
        node: Optional[Node] = None,
        uuids: Optional[list[str]] = None,
        limit: Optional[int] = 10,
        with_labels: Optional[list[str]] = None,
    ) -> list[Tuple[Node, Predicate, Node]]:
        """
        Get the connected nodes by their UUIDs.
        """
        return self.graph.get_connected_nodes(
            brain_id, node=node, uuids=uuids, limit=limit, with_labels=with_labels
        )

    def search_relationships(
        self,
        brain_id: str = "default",
        limit: int = 10,
        skip: int = 0,
        relationship_types: Optional[list[str]] = None,
        from_node_labels: Optional[list[str]] = None,
        to_node_labels: Optional[list[str]] = None,
        query_text: Optional[str] = None,
        query_search_target: Optional[str] = "all",
    ) -> SearchRelationshipsResult:
        """
        Search the relationships of the graph.
        """
        relationship_uuids = []
        return self.graph.search_relationships(
            brain_id,
            limit,
            skip,
            relationship_types,
            from_node_labels,
            to_node_labels,
            relationship_uuids,
            query_text,
            query_search_target,
        )

    def search_entities(
        self,
        brain_id: str = "default",
        limit: int = 10,
        skip: int = 0,
        node_labels: Optional[list[str]] = None,
        query_text: Optional[str] = None,
    ) -> SearchEntitiesResult:
        """
        Search the entities of the graph.
        """
        node_uuids = []
        return self.graph.search_entities(
            brain_id, limit, skip, node_labels, node_uuids, query_text
        )

    def search_nodes_bm25(
        self,
        query_text: str,
        brain_id: str = "default",
        *,
        limit: int = 10,
        node_labels: Optional[list[str]] = None,
        node_uuids: Optional[list[str]] = None,
    ):
        method = getattr(self.graph, "search_nodes_bm25", None)
        if method is None:
            return []
        return method(
            query_text,
            brain_id,
            limit=limit,
            node_labels=node_labels,
            node_uuids=node_uuids,
        )

    def deprecate_relationship(
        self,
        subject: Node,
        predicate: Predicate,
        object: Node,
        brain_id: str = "default",
    ) -> Tuple[Node, Predicate, Node] | None:
        """
        Deprecate a relationship from the graph.
        """
        return self.graph.deprecate_relationship(subject, predicate, object, brain_id)

    def update_properties(
        self,
        uuid: str,
        updating: Literal["node", "relationship"],
        brain_id: str = "default",
        new_properties: Optional[dict] = None,
        properties_to_remove: Optional[list[str]] = None,
    ) -> Node | Predicate | None:
        """
        Update properties on a graph node or relationship.

        Parameters:
                uuid (str): UUID of the node or relationship to update.
                updating (Literal["node", "relationship"]): Target entity type to update.
                brain_id (str): Identifier of the graph (defaults to "default").
                new_properties (dict): Properties to add or replace on the entity.
                properties_to_remove (list[str]): Names of properties to remove from the entity.

        Returns:
                Node | Predicate | None: The updated entity, or `None` if the entity was not found.
        """
        if new_properties is None:
            new_properties = {}
        if properties_to_remove is None:
            properties_to_remove = []
        return self.graph.update_properties(
            uuid, updating, brain_id, new_properties, properties_to_remove
        )

    def get_graph_relationship_types(self, brain_id: str = "default") -> list[str]:
        """
        Retrieve all relationship type names present in the graph.

        Parameters:
            brain_id (str): Identifier of the graph (brain) to query. Defaults to "default".

        Returns:
            list[str]: List of unique relationship type names found in the graph.
        """
        return self.graph.get_graph_relationship_types(brain_id)

    def get_graph_node_types(self, brain_id: str = "default") -> list[str]:
        """
        Get all unique node types stored in the graph.

        Returns:
            list[str]: Node type names available in the graph.
        """
        return self.graph.get_graph_node_types(brain_id)

    def get_graph_node_properties(self, brain_id: str = "default") -> list[str]:
        """
        Return all unique node property keys present in the graph for the specified brain.

        Returns:
            list[str]: Unique node property key names present in the specified brain's graph.
        """
        return self.graph.get_graph_node_properties(brain_id)

    def update_node(
        self,
        uuid: str,
        brain_id: str = "default",
        new_name: Optional[str] = None,
        new_description: Optional[str] = None,
        new_labels: Optional[list[str]] = None,
        new_properties: Optional[dict] = None,
        properties_to_remove: Optional[list[str]] = None,
    ) -> Node | None:
        """
        Update an existing node's identifying fields, labels, and properties in the graph.

        Parameters:
            uuid (str): UUID of the node to update.
            brain_id (str): Identifier of the brain/graph where the node resides.
            new_name (Optional[str]): New name for the node; leave None to keep the current name.
            new_description (Optional[str]): New description for the node; leave None to keep the current description.
            new_labels (Optional[list[str]]): New set of labels for the node; provide to replace the node's labels.
            new_properties (Optional[dict]): Properties to add or update on the node; keys are property names and values are their new values.
            properties_to_remove (Optional[list[str]]): List of property names to remove from the node.

        Returns:
            Node | None: The updated node if the update succeeded, or `None` if the node was not found.
        """
        return self.graph.update_node(
            uuid,
            brain_id,
            new_name,
            new_description,
            new_labels,
            new_properties,
            properties_to_remove,
        )

    def get_schema(self, brain_id: str = "default") -> dict:
        """
        Get the schema/ontology of the graph.
        """
        return self.graph.get_schema(brain_id)

    def _reduce_neighbor_vectors(
        self,
        vectors_with_desc: list[dict],
        averaged_vector: list[float],
        similarity_threshold: float,
        description: Optional[str],
    ) -> set[str]:
        if not vectors_with_desc or not averaged_vector:
            return set()
        strategy = self._reduction_strategy_factory.create(description)
        reduced_vectors = strategy.prefilter(
            vectors_with_desc=vectors_with_desc,
            averaged_vector=averaged_vector,
            description=description,
        )
        filtered_uuids = set()
        for vector in reduced_vectors:
            vector_uuid = vector.get("metadata", {}).get("uuid")
            embeddings = vector.get("embeddings")
            if (
                not vector_uuid
                or not embeddings
                or not isinstance(embeddings, list)
                or len(embeddings) != len(averaged_vector)
            ):
                continue
            if cosine_similarity(averaged_vector, embeddings) >= similarity_threshold:
                filtered_uuids.add(vector_uuid)
        return filtered_uuids

    def _average_embeddings(self, vectors: list[Vector]) -> list[float]:
        valid_embeddings = [
            vector.embeddings for vector in vectors if isinstance(vector.embeddings, list) and vector.embeddings
        ]
        if not valid_embeddings:
            return []
        dimension = len(valid_embeddings[0])
        same_dimension_embeddings = [
            embedding for embedding in valid_embeddings if len(embedding) == dimension
        ]
        if not same_dimension_embeddings:
            return []
        return [
            sum(embedding[i] for embedding in same_dimension_embeddings)
            / len(same_dimension_embeddings)
            for i in range(dimension)
        ]

    def get_2nd_degree_hops(
        self,
        from_uuids: List[str],
        flattened: bool,
        vector_store_adapter: VectorStoreClient,
        brain_id: str = "default",
        similarity_threshold: float = 0.0,
    ) -> List[Tuple[Node, List[Tuple[Predicate, Node, List[Tuple[Predicate, Node]]]]]]:
        """
        Compute second-degree neighbor hops for the given starting node UUIDs using vector-store–based filtering.

        Parameters:
            from_uuids: List[str] — UUIDs of the starting nodes to explore.
            flattened: bool — When true, nodes and predicates are returned as lightweight dicts with core fields (`uuid`, `name`, `labels`/`direction`) instead of full objects.
            vector_store_adapter: VectorStoreClient — Vector store used to fetch embeddings and perform similarity-based filtering.
            brain_id: str — Identifier of the brain/graph space to query.
            similarity_threshold: float — Optional threshold for additional similarity-based filtering (0.0 disables the extra check).

        Returns:
            List[Tuple[Node, List[Tuple[Predicate, Node, List[Tuple[Predicate, Node]]]]]] — A list where each item corresponds to a starting node and contains:
                - the starting node (or its flattened representation),
                - a list of first-degree entries, each being a tuple of (predicate, first-degree node, list of second-degree (predicate, node) tuples).
        """

        def flatten_node(n):
            """
            Return a flattened node representation when the surrounding `flattened` flag is true, otherwise return the original node.

            Parameters:
                n: Node
                    The node to convert.

            Returns:
                dict: A dictionary with keys `uuid`, `labels`, and `name` when `flattened` is true, otherwise the original node object.
            """
            return (
                {"uuid": n.uuid, "labels": n.labels, "name": n.name} if flattened else n
            )

        def flatten_pred(p):
            return (
                {"uuid": p.uuid, "name": p.name, "direction": p.direction}
                if flattened
                else p
            )

        nodes = self.get_by_uuids(from_uuids, brain_id)
        nodes_by_uuid = {n.uuid: n for n in nodes}

        v_ids = [
            n.properties["v_id"] for n in nodes if n.properties.get("v_id") is not None
        ]
        if len(v_ids) == 0:
            print(
                "[ ! ] No v_ids found for nodes:", from_uuids
            )  # TODO: no node without v_id exists in the graph, check why this is happening
            print(f"[DEBUG (get_2nd_degree_hops)]: Nodes: {nodes}")
            return []

        vs = vector_store_adapter.get_by_ids(v_ids, brain_id=brain_id, store="nodes")
        if len(vs) == 0:
            print("[ ! ] No vectors found for nodes:", from_uuids)
            return []

        averaged_vector = self._average_embeddings(vs)
        if len(averaged_vector) == 0:
            print("[ ! ] No valid embeddings found for nodes:", from_uuids)
            return []

        all_fd_nodes = self.get_neighbors(list(nodes_by_uuid.keys()), brain_id=brain_id)

        all_fd_v_ids: List[str] = [
            fd[1].properties["v_id"]
            for fds in all_fd_nodes.values()
            for fd in fds
            if fd[1].properties.get("v_id") is not None
        ]  # TODO: [missing_property] check why sometime v_id is not present
        all_fd_vs = (
            vector_store_adapter.get_by_ids(all_fd_v_ids, brain_id=brain_id, store="nodes")
            if len(all_fd_v_ids) > 0
            else []
        )
        fd_vs_by_uuid: Dict[str, Vector] = {v.metadata["uuid"]: v for v in all_fd_vs}

        all_filtered_fd_uuids: set[str] = set()
        filtered_fd_by_origin: Dict[str, List[Tuple[Predicate, Node]]] = {}

        for node_uuid, fd_list in all_fd_nodes.items():
            fd_nodes_by_uuid = {fd[1].uuid: fd[1] for fd in fd_list}
            fd_vs_with_desc = [
                {
                    "embeddings": fd_vs_by_uuid[fd[1].uuid].embeddings,
                    "metadata": fd_vs_by_uuid[fd[1].uuid].metadata,
                    "description": (
                        fd_nodes_by_uuid.get(fd[1].uuid, {}).description
                        if fd_nodes_by_uuid.get(fd[1].uuid)
                        else None
                    ),
                }
                for fd in fd_list
                if fd[1].uuid in fd_vs_by_uuid
            ]
            from_node = nodes_by_uuid[node_uuid]
            filtered_uuids = self._reduce_neighbor_vectors(
                vectors_with_desc=fd_vs_with_desc,
                averaged_vector=averaged_vector,
                similarity_threshold=similarity_threshold,
                description=from_node.description,
            )
            filtered_fd_by_origin[node_uuid] = [
                fd for fd in fd_list if fd[1].uuid in filtered_uuids
            ]
            all_filtered_fd_uuids.update(filtered_uuids)

        all_sd_nodes = (
            self.get_neighbors(list(all_filtered_fd_uuids), brain_id=brain_id)
            if len(all_filtered_fd_uuids) > 0
            else {}
        )

        all_sd_v_ids: List[str] = [
            getattr(sd[1], "properties", {}).get("v_id")
            for sds in all_sd_nodes.values()
            for sd in sds
            if getattr(sd[1], "properties", {}).get(
                "v_id"
            )  # TODO: [missing_property] check why sometime v_id is not present
        ]
        all_sd_vs = (
            vector_store_adapter.get_by_ids(all_sd_v_ids, brain_id=brain_id, store="nodes")
            if len(all_sd_v_ids) > 0
            else []
        )
        sd_vs_by_uuid = {v.metadata["uuid"]: v for v in all_sd_vs}

        hops = []
        exclude_set = set(from_uuids)

        for from_uuid in from_uuids:
            if from_uuid not in nodes_by_uuid:
                continue
            from_node = nodes_by_uuid[from_uuid]
            node_hops = []

            for fd_pred, fd_node in filtered_fd_by_origin.get(from_uuid, []):
                sd_list = all_sd_nodes.get(fd_node.uuid, [])
                sd_nodes_by_uuid = {sd[1].uuid: sd[1] for sd in sd_list}

                sd_vs_with_desc = [
                    {
                        "embeddings": sd_vs_by_uuid[sd[1].uuid].embeddings,
                        "metadata": sd_vs_by_uuid[sd[1].uuid].metadata,
                        "description": (
                            sd_nodes_by_uuid.get(sd[1].uuid, {}).description
                            if sd_nodes_by_uuid.get(sd[1].uuid)
                            else None
                        ),
                    }
                    for sd in sd_list
                    if sd[1].uuid in sd_vs_by_uuid
                ]

                reduced_uuids = self._reduce_neighbor_vectors(
                    vectors_with_desc=sd_vs_with_desc,
                    averaged_vector=averaged_vector,
                    similarity_threshold=similarity_threshold,
                    description=from_node.description,
                )

                second_degree = [
                    (flatten_pred(sd[0]), flatten_node(sd[1]))
                    for sd in sd_list
                    if sd[1].uuid in reduced_uuids
                    and sd[1].uuid not in exclude_set
                    and sd[1].uuid != from_uuid
                ]

                node_hops.append(
                    (flatten_pred(fd_pred), flatten_node(fd_node), second_degree)
                )

            hops.append((flatten_node(from_node), node_hops))

        return hops

    def check_node_existence(
        self,
        uuid: str,
        name: str,
        labels: list[str],
        brain_id: str = "default",
    ) -> bool:
        """
        Determine whether a node with the given UUID, name, and labels exists in the graph.

        Parameters:
                uuid (str): UUID of the node to check; may be empty if matching by name and labels.
                name (str): Name of the node to match.
                labels (list[str]): List of labels/types the node must have.
                brain_id (str): Identifier of the graph/brain to query; defaults to "default".

        Returns:
                true if a matching node exists, false otherwise.
        """
        return self.graph.check_node_existence(uuid, name, labels, brain_id)

    def get_neighborhood(
        self, node: Node | str, depth: int, brain_id: str = "default"
    ) -> list[dict]:
        """
        Get the neighborhood of a node up to a given depth.
        Returns a nested structure where each neighbor contains its own neighbors.
        """
        return self.graph.get_neighborhood(node, depth, brain_id)

    def traverse_graph(
        self,
        *,
        brain_id: str = "default",
        start_uuid: str | None = None,
        start_name: str | None = None,
        start_labels: list[str] | None = None,
        depth: int = 2,
        rel_types: list[str] | None = None,
        node_labels: list[str] | None = None,
        direction: Literal["in", "out", "both"] = "both",
        limit: int = 50,
    ) -> dict:
        depth = max(1, min(depth, MAX_TRAVERSE_DEPTH))
        limit = max(1, min(limit, MAX_TRAVERSE_HOPS))

        if start_uuid:
            start_node = self.get_by_uuid(start_uuid, brain_id)
        elif start_name and start_labels:
            start_node = self.get_by_identification_params(
                IdentificationParams(name=start_name),
                brain_id,
                entity_types=start_labels,
            )
        else:
            return {
                "error": "Provide start_uuid or both start_name and start_labels",
            }

        if start_node is None:
            return {"error": "Start node not found"}

        neighborhood = self.get_neighborhood(start_node.uuid, depth, brain_id)
        hops, truncated = flatten_neighborhood(
            neighborhood,
            rel_types=rel_types,
            node_labels=node_labels,
            direction=direction,
            limit=limit,
        )
        return {
            "start": start_node.model_dump(mode="json"),
            "depth": depth,
            "hops": hops,
            "truncated": truncated,
        }

    def get_nexts_by_flow_key(
        self,
        predicates: list[PredicateWithFlowKey],
        brain_id: str = "default",
    ) -> Dict[str, List[Tuple[Node, Predicate, Node]]]:
        """
        Retrieve the next connected node tuple(s) for a relationship identified by a flow key, grouped by the predicate UUID.

        Parameters:
            predicates (list[PredicateWithFlowKey]): A list of predicates with their flow keys.
            brain_id (str): Identifier of the brain/graph namespace to query.

        Returns:
            Dict[str, List[Tuple[Node, Predicate, Node]]]: A dictionary mapping predicate UUIDs to lists of (subject node, predicate, object node) tuples that are the next nodes matching the provided flow key; empty dictionary if none are found for any predicate UUID.
        """
        return self.graph.get_nexts_by_flow_key(predicates, brain_id)

    def get_triples_by_uuid(
        self, uuids: list[str], brain_id: str
    ) -> List[Tuple[Node, Predicate, Node]]:
        """
        Get triples by its UUIDs.
        """
        return self.graph.get_triples_by_uuid(uuids, brain_id)

    def remove_nodes(self, uuids: list[str], brain_id: str = "default") -> list[Node]:
        """
        Remove nodes from the graph.
        """
        return self.graph.remove_nodes(uuids, brain_id)

    def remove_relationships(
        self,
        relationships: list[Tuple[NodeDict, PredicateDict, NodeDict]],
        brain_id: str = "default",
    ) -> list[Tuple[Node, Predicate, Node]]:
        """
        Remove relationships from the graph.
        """
        return self.graph.remove_relationships(relationships, brain_id)

    def list_relationships(
        self,
        subject: str,
        object: str,
        brain_id: str = "default",
    ) -> list[Tuple[Node, Predicate, Node]]:
        """
        List the relationships between the subject and object.
        """
        return self.graph.list_relationships(subject, object, brain_id)

    def get_event_hub_facts(
        self,
        event_uuids: list[str],
        brain_id: str = "default",
    ) -> list:
        return self.graph.get_event_hub_facts(event_uuids, brain_id)

    def rebuild_hub_bridge_index(self, brain_id: str = "default") -> int:
        return self.graph.rebuild_hub_bridge_index(brain_id)

    def refresh_hub_bridges_for_entities(
        self, entity_uuids: list, brain_id: str = "default"
    ) -> int:
        refresh = getattr(self.graph, "refresh_hub_bridges_for_entities", None)
        if refresh is None:
            return self.rebuild_hub_bridge_index(brain_id)
        return int(refresh(brain_id, list(entity_uuids or [])) or 0)

    def get_hub_bridges(
        self,
        event_uuids: list[str],
        brain_id: str = "default",
    ) -> list:
        return self.graph.get_hub_bridges(event_uuids, brain_id)

    def rebuild_topic_index(self, brain_id: str = "default") -> int:
        rebuild = getattr(self.graph, "rebuild_topic_index", None)
        if rebuild is None:
            return 0
        return int(rebuild(brain_id) or 0)

    def list_topic_memberships(self, brain_id: str = "default") -> list:
        listing = getattr(self.graph, "list_topic_memberships", None)
        if listing is None:
            return []
        return list(listing(brain_id) or [])


_graph_adapter = GraphAdapter()