#! /usr/bin/env python
# -*- coding: utf-8 -*-
# vim:fenc=utf-8
#
# Copyright © 2017 lafrite <lafrite@Poivre>
#
# Distributed under terms of the MIT license.

"""
Tools to extract random nodes, random variables, generate random values and
fill new trees

Flow
----

Tree with RdLeaf
|
| Extract nodes
|
List of nodes to generate
|
| extract_rv
|
List random variables to generate
|
| Generate
|
Dictionnary of generated random variables
|
| Compute nodes
|
Dictionnary of computed nodes
|
| Replace
|
Tree with RdLeaf replaced by generated values

"""


def extract_rv(node_list):
    """ Extract the set of random values from the node list

    :param node_list: list of nodes
    :return: set of random values

    :example:
    >>> node_list = ["{a}", "{a*k}"]
    >>> extract_rv(node_list)
    {"a", "k"}
    """
    pass

def compute_nodes(node_list, generated_values):
    """ Compute nodes from generated random values

    :param generated_values: Dictionnary of name:generated value
    :param node_list: list of nodes
    :return: Dictionnary of evaluated nodes from generated values

    :example:
    >>> node_list = ["{a}", "{a*k}"]
    >>> generated_values = {"a":2, "k":3}
    >>> compute_nodes(node_list, generated_values)
    {"{a}": 2, "{a*k}": 6} 
    """
    pass