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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
    cost: float
    local_cost: float
    adjusted_ce: float
    children: list[Node]

    def print(self, level=0):
        """Pretty print of the ABT."""
        print(
            f'{"| "*level}{self.node_type}, planNodeId: {self.plan_node_id}, cost: {self.cost:0.5f}, localCost: {self.local_cost:0.5f}, adjustedCE: {self.adjusted_ce:0.2f}'
        )
        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)
    properties = explain_node['properties']
    return Node(node_type=explain_node['nodeType'], plan_node_id=properties['planNodeID'],
                cost=properties['cost'], local_cost=properties['localCost'],
                adjusted_ce=properties['adjustedCE'], children=children)


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

    children_refs = ['child', 'leftChild', 'rightChild']

    for ref in children_refs:
        if ref in explain_node:
            children.append(parse_optimizer_node(explain_node[ref]))
    return children