ast.hpp

// Copyright 2022 Arnaud Becheler    <abechele@umich.edu>
 
/*********************************************************************** * This program is free software; you can
 *redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free
 *Software Foundation; either version 2 of the License, or    * (at your option) any later version. *
 *                                                                      *
 ***************************************************************************/
 
#pragma once
 
#include <boost/spirit/home/x3.hpp>
#include <boost/spirit/home/x3/support/ast/variant.hpp>
 
#include <boost/fusion/adapted/struct/adapt_struct.hpp>
#include <boost/fusion/include/adapt_struct.hpp>
 
#include <iomanip>
 
namespace quetzal::format::newick::ast
{
 
using nodes = std::vector<struct node>;
 
struct node
{
    using vertex_property = std::string;
 
    using edge_property = double;
 
    nodes children;
 
    vertex_property name;
 
    edge_property distance_to_parent;
};
 
static inline std::ostream &print_subtree(node const &node, const std::string &prefix, std::ostream &os)
{
    // if tree is more than a simple root node
    if (!node.children.empty())
    {
        // print a prefix growing with depth
        os << prefix;
 
        size_t nb_children = node.children.size();
 
        // Bifurcation if more than 1 child
        if (nb_children > 1)
            os << "├──";
 
        for (size_t i = 0; i < nb_children; ++i)
        {
            const auto &child = node.children[i];
            // If not the last child
            if (i < nb_children - 1)
            {
                // If not the first child
                if (i > 0)
                    os << prefix << "├──";
 
                bool should_print_branch = nb_children > 1 && !child.children.empty();
                auto new_prefix = prefix + (should_print_branch ? "│\t" : "\t");
                os << child.distance_to_parent << "──" << std::quoted(child.name) << "\n";
                print_subtree(child, new_prefix, os);
            }
            // If the last child
            else
            {
                if (nb_children > 1)
                    os << prefix;
                os << "└──" << child.distance_to_parent << "──" << std::quoted(child.name) << "\n";
                print_subtree(child, prefix + "\t", os);
            }
        }
    }
    return os;
}
 
static inline std::ostream &operator<<(std::ostream &os, node const &n)
{
    os << std::quoted(n.name) << "\n";
    return print_subtree(n, "", os);
}
 
} // namespace quetzal::format::newick::ast
 
BOOST_FUSION_ADAPT_STRUCT(quetzal::format::newick::ast::node, children, name, distance_to_parent)