/*
 *  <Short Description>
 *  Copyright (C) 2024  Brett Terpstra
 *
 *  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 <https://www.gnu.org/licenses/>.
 */

#ifndef GP_IMAGE_TEST_GP_H
#define GP_IMAGE_TEST_GP_H

#include <config.h>
#include <functions.h>
#include <random>

struct node;
class tree;

node* createNode(function_t type);
void destroyNode(node* n);

struct node
{
        friend tree;
    private:
        // only valid up to the argc
        std::array<node*, MAX_ARGS> sub_nodes{nullptr};
        size_t argc = 0;
        
        function_t type = function_t::ADD;
        data_t data{};
        
        std::optional<image> img;
        
        void grow(bool use_terminals);
        
        void full(bool use_terminals);
        
        void populate_node(size_t i, std::mt19937_64& engine, const allowed_funcs<function_t>& allowed_args, bool use_terminal);
        
        void print_tree();
    
    public:
        explicit node(function_t type): type(type)
        {
            static thread_local std::random_device dev;
            static thread_local std::mt19937_64 engine{dev()};
            static thread_local std::uniform_real_distribution<float> dist(0.0f, 1.0f);
            if (type == function_t::SCALAR)
                data[0] = dist(engine);
            else if (type == function_t::COLOR)
            {
                for (auto& v : data)
                    v = dist(engine);
            }
        }
        
        static node* construct_random_tree();
        
        void evaluate();
        
        void evaluate_tree()
        {
            for (size_t i = 0; i < argc; i++)
                sub_nodes[i]->evaluate_tree();
            evaluate();
        }
        
        void printTree()
        {
            print_tree();
            std::cout << std::endl;
        }
        
        bool hasImage()
        {
            return img.has_value();
        }
        
        image& getImage()
        {
            return img.value();
        }
        
        ~node()
        {
            for (auto* node : sub_nodes)
                destroyNode(node);
        }
};

struct node_deleter
{
    void operator()(node* ptr)
    {
        destroyNode(ptr);
    }
};

#endif //GP_IMAGE_TEST_GP_H