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"""Define ABT physical tree and parse it from query explain."""

from __future__ import annotations
from dataclasses import dataclass

__all__ = ['Node', 'build']


@dataclass
class Node:
    """Represent ABT node."""

    node_type: str
    plan_node_id: int
    children: list[Node]

    def print(self, level=0):
        """Pretty print of the ABT."""
        print(f'{"| "*level}nodeType: {self.node_type}, plaNodeId: {self.plan_node_id}')
        for child in self.children:
            child.print(level + 1)


def build(optimizer_plan: dict[str, any]) -> Node:
    """Build ABT from query explain."""
    return parse_optimizer_node(optimizer_plan)


def parse_optimizer_node(explain_node: dict[str, any]) -> Node:
    """Recursively parse ABT node from query explain's node."""
    children = get_children(explain_node)
    return Node(node_type=explain_node['nodeType'], plan_node_id=explain_node['properties'].get(
        'planNodeID', -1), children=children)


def get_children(explain_node: dict[str, any]) -> list[Node]:
    """Get children nodes of the ABT node."""
    children_refs = ['child', 'leftChild', 'rightChild']
    children = []
    for ref in children_refs:
        if ref in explain_node:
            children.append(parse_optimizer_node(explain_node[ref]))
    return children