/*

Copyright (C) 2017-2026 Topological Manifold

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 3 of the License, or

(at your option) any later version.

This program is distributed in the hope that it will be useful,

but WITHOUT ANY WARRANTY; without even the implied warranty of

MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the

GNU General Public License for more details.

You should have received a copy of the GNU General Public License

along with this program. If not, see <http://www.gnu.org/licenses/>.

*/

#include "string_tree.h"

#include <src/com/error.h>

#include <cstddef>

#include <ranges>

#include <stack>

#include <string>

#include <tuple>

#include <utility>

namespace ns

{

constexpr std::size_t ROOT_NODE = 0;

StringTree::StringTree()

{

nodes_.emplace_back("");

}

std::size_t StringTree::add(std::string s)

{

nodes_.emplace_back(std::move(s));

nodes_[ROOT_NODE].children.push_back(nodes_.size() - 1);

return nodes_.size() - 1;

}

std::size_t StringTree::add(const std::size_t parent, std::string s)

{

if (parent >= nodes_.size())

{

error("Node parent out of range");

}

nodes_.emplace_back(std::move(s));

nodes_[parent].children.push_back(nodes_.size() - 1);

return nodes_.size() - 1;

}

std::string StringTree::text(const unsigned indent) const

{

std::string res;

std::stack<std::tuple<std::size_t, unsigned>> stack({

{ROOT_NODE, 0}

});

while (!stack.empty())

{

const auto [index, level] = stack.top();

stack.pop();

if (level > 0)

{

if (!res.empty())

{

res += '\n';

}

const unsigned level_indent = (level - 1) * indent;

res += std::string(level_indent, ' ');

res += nodes_[index].name;

}

for (const std::size_t child : std::ranges::reverse_view(nodes_[index].children))

{

stack.emplace(child, level + 1);

}

}

return res;

}

}