"""Body-graph executors (boolean_bodies / transform_bodies / delete_bodies).

These operate on explicitly named body members instead of the aggregate
session body, so adjacent independent solids never accidentally become tools
or targets of one another.
"""

from __future__ import annotations

from typing import TYPE_CHECKING, Any

from ..registry import atomic_executor
from ..specs import transform_copy_member_id
from ..topology import FeaturePlanNode, FeatureResult, TopologyDelta
from .common import _combine_members, _member_sources

if TYPE_CHECKING:  # pragma: no cover - import for type checkers only
    from ..session import ExecutionSession


def _execute_boolean_bodies(node: FeaturePlanNode, session: "ExecutionSession") -> FeatureResult:
    # booleanBodies 总是作用于 source feature 的明确 body 输出，不能回退为
    # 当前聚合 body。这样相邻独立实体不会意外成为工具或目标。
    params = node.params
    target_ids = _member_sources(
        node, session, "target_feature_ids", pattern_instance_parameter="target_pattern_instance_refs",
        allow_transform_copies=True, transform_copy_parameter="target_transform_copy_refs",
    )
    tool_ids = _member_sources(
        node, session, "tool_feature_ids", pattern_instance_parameter="tool_pattern_instance_refs",
        allow_transform_copies=True, transform_copy_parameter="tool_transform_copy_refs",
    )
    targets = {feature_id: session.body_members[feature_id] for feature_id in target_ids}
    tools = {feature_id: session.body_members[feature_id] for feature_id in tool_ids}
    target = _combine_members(session, targets)
    tool = _combine_members(session, tools)
    operation = str(params.get("operation") or "")
    topology_delta: TopologyDelta | None = None
    if operation == "union":
        result, topology_delta = session.adapter.fuse_with_topology_delta(target, tool)
    elif operation == "subtract":
        result, topology_delta = session.adapter.cut_with_topology_delta(target, tool)
    elif operation == "intersect":
        result, topology_delta = session.adapter.intersect_with_topology_delta(target, tool)
    else:
        raise ValueError(f"unsupported booleanBodies operation {operation!r}")
    members = {
        feature_id: body
        for feature_id, body in session.body_members.items()
        if feature_id not in set(target_ids + tool_ids)
    }
    members[node.feature_id] = result
    if bool(params.get("keep_tools")):
        # In a targetless FeatureScript body-set operation every selected
        # member is semantically a tool. Lowering chooses the first source
        # member only to satisfy CDSL's binary executor shape, so retain that
        # left operand too when the explicit targetless contract requests it.
        if bool(params.get("targetless_body_set")):
            members.update(targets)
        members.update(tools)
    session.register_body(
        node.feature_id, _combine_members(session, members), body_members=members, topology_delta=topology_delta,
    )
    return session.result(node)


@atomic_executor("boolean_bodies")
def _boolean_bodies_executor(node: FeaturePlanNode, session: "ExecutionSession", sketch: dict[str, Any] | None) -> FeatureResult:
    del sketch
    return _execute_boolean_bodies(node, session)


def _execute_transform_bodies(node: FeaturePlanNode, session: "ExecutionSession") -> FeatureResult:
    # FeatureScript transform targets explicit bodies.  Do not move the
    # aggregate session body, because it may include unrelated members.
    source_ids = _member_sources(
        node, session, "source_feature_ids", pattern_instance_parameter="pattern_instance_refs", allow_transform_copies=True,
    )
    make_copy = bool(node.params.get("make_copy"))
    direct_sources = node.params.get("source_feature_ids") or []
    if make_copy and isinstance(direct_sources, list) and len(direct_sources) > 1:
        # The aggregate is only an export compound. Each source transform has
        # its own B-rep builder and is the only output a later COPY query may
        # select. Do not attach an aggregate topology delta to source members.
        members = dict(session.body_members)
        members.update({
            transform_copy_member_id(node.feature_id, source_id): session.adapter.transform(
                session.body_members[source_id], dict(node.params.get("transform") or {}),
            )
            for source_id in source_ids
        })
        session.register_body(
            node.feature_id, _combine_members(session, members), body_members=members,
        )
        return session.result(node)
    source = _combine_members(session, {feature_id: session.body_members[feature_id] for feature_id in source_ids})
    transformed, topology_delta = session.adapter.transform_with_topology_delta(
        source, dict(node.params.get("transform") or {}),
    )
    members = dict(session.body_members)
    if not make_copy:
        for feature_id in source_ids:
            members.pop(feature_id)
    members[node.feature_id] = transformed
    session.register_body(
        node.feature_id, _combine_members(session, members), body_members=members, topology_delta=topology_delta,
    )
    return session.result(node)


@atomic_executor("transform_bodies")
def _transform_bodies_executor(node: FeaturePlanNode, session: "ExecutionSession", sketch: dict[str, Any] | None) -> FeatureResult:
    del sketch
    return _execute_transform_bodies(node, session)


def _execute_delete_bodies(node: FeaturePlanNode, session: "ExecutionSession") -> FeatureResult:
    # Deletion is a body-graph operation, never a Boolean subtraction.  A
    # selected member can be disjoint or overlap another independent body.
    source_ids = _member_sources(node, session, "target_feature_ids")
    members = {feature_id: body for feature_id, body in session.body_members.items() if feature_id not in set(source_ids)}
    if members:
        session.register_body(node.feature_id, _combine_members(session, members), body_members=members)
    else:
        session.clear_body()
    return session.result(node)


@atomic_executor("delete_bodies")
def _delete_bodies_executor(node: FeaturePlanNode, session: "ExecutionSession", sketch: dict[str, Any] | None) -> FeatureResult:
    del sketch
    return _execute_delete_bodies(node, session)