/*
* File name: main.cpp
* Author: lejulien
* Date created: 10-01-2026 21:59:32
// Date modified: 12-01-2026 22:17:54
* ------
*/

#include <fstream>
#include <iostream>
#include <unistd.h>
#include <nlohmann/json.hpp>

#include <imgui.h>
#include <raylib.h>
#include <rlImGui.h>

#include <render.hpp>
#include <rules.hpp>
#include <world.hpp>
#include <types.hpp>
#include <context.hpp>
#include <control_menu.hpp>
#include <settings_menu.hpp>
#include <selection_menu.hpp>
#include <selection.hpp>
#include <paterns_menu.hpp>

int main(int ac, char **av) {
  std::shared_ptr<gol::ctx> context = std::make_shared<gol::ctx>();
  // Load or default config
  const std::string config_file_name = "config.json";

  std::fstream config_file(config_file_name, std::ios::in | std::ios::out);

  if (!config_file.is_open()) {
    config_file.open(config_file_name, std::ios::out);
    if (!config_file) {
      std::cerr << "Failed to create config file, the settings will not be "
                   "kepts after restart."
                << std::endl;
      return 1;
    }
    config_file.close();
    config_file.open(config_file_name, std::ios::in | std::ios::out);
    config_file << "{}";
    config_file.flush();
  }
  // Try reading the configuration
  try {
    config_file.seekg(0);
    config_file >> context->config_json;
  } catch (const nlohmann::json::parse_error &e) {
    std::cerr << "An error occured while loading config : " << e.what()
              << std::endl;
    std::cerr << "Please fix the configuration or remove the config.json file."
              << std::endl;
    return 1;
  }
  config_file.close();

  // Check config values or populate them
  if (!context->config_json.contains("cell_size") ||
      (context->config_json["cell_size"] < 4 || context->config_json["cell_size"] > 100)) {
    context->config_json["cell_size"] = 10;
  }
  if (!context->config_json.contains("screen_width") ||
      (context->config_json["screen_width"] < 800 ||
       context->config_json["screen_width"] > 1920)) {
    context->config_json["screen_width"] = 800;
  }
  if (!context->config_json.contains("screen_height") ||
      (context->config_json["screen_height"] < 600 ||
       context->config_json["screen_height"] > 1200)) {
    context->config_json["screen_height"] = 600;
  }
  if (!context->config_json.contains("dark_theme")) {
    context->config_json["dark_theme"] = true;
  }
  if (!context->config_json.contains("fps") ||
      (context->config_json["fps"] < 0 || context->config_json["fps"] > 30)) {
    context->config_json["fps"] = 800;
  }

  // Get program directory
  char path_buf[1024];
  ssize_t len = readlink("/proc/self/exe", path_buf, sizeof(path_buf)-1);
  if (len == -1) {
    std::cerr << "Failed to determine program directory" << std::endl;
    return 1;
  }
  context->program_dir = std::filesystem::path(path_buf).parent_path();

  InitWindow(context->config_json["screen_width"], context->config_json["screen_height"],
             &av[0][2]);

  SetTargetFPS(60);

  rlImGuiSetup(context->config_json["dark_theme"]);

  // Initialize objects
  context->control_menu = std::make_shared<gol::ControlMenu>(context);
  context->world = std::make_shared<World>(context);
  context->rules = std::make_shared<Rules>();
  context->settings_menu = std::make_shared<gol::SettingsMenu>(context);
  context->render = std::make_shared<Render>(context->settings_menu->getCellSize());
  context->selection_menu = std::make_shared<gol::SelectionMenu>(context);
  context->selection = std::make_shared<gol::Selection>(context);
  context->paterns_menu = std::make_shared<gol::PaternsMenu>(context);

  // Speed handling values
  float sim_speed = 1.0f;
  float deltaTimeAccumulator = 0.0f;
  float timePerUpdate = 1.0f / 10.0f;

  // Setups
  context->rules->setup(context->world);
  context->paterns_menu->refresh();
  // Diplay generations
  while (!WindowShouldClose()) {
    // Frames shinenigans
    float deltaTime = GetFrameTime();
      sim_speed = context->settings_menu->getFPS() / 10.0f;
    timePerUpdate = (1.0f / 10.0f) / sim_speed;

    context->control_menu->update();

    auto gesture = GetGestureDetected();
    auto mousePos = GetMousePosition();
    if (context->control_menu->edit_ctrl_ && IsMouseButtonPressed(0) &&
        !ImGui::IsWindowHovered(ImGuiHoveredFlags_AnyWindow)) {
      context->control_menu->menu_state_ = MenuState::EDIT;
      context->world->setCell(mousePos.x / context->config_json["cell_size"].get<int>(),
                    mousePos.y / context->config_json["cell_size"].get<int>());
    }

    // Selection behaviour
    context->selection->update();
    context->selection_menu->update();
    context->settings_menu->update();

    // Accumulate time and update simulation at the adjusted speed
    deltaTimeAccumulator += deltaTime;

    if (deltaTimeAccumulator >= timePerUpdate) {
      // Reset accumulator
      deltaTimeAccumulator -= timePerUpdate;
      if (context->control_menu->menu_state_ == MenuState::PLAY) {
        context->world->saveCompressed();
        context->rules->update();
      }
    }
    BeginDrawing();
    ClearBackground(BLACK);
    context->render->display(context->world);
    context->selection->display();
    // Start ImGui frame
    rlImGuiBegin();
    context->control_menu->display();
    context->paterns_menu->display();
    context->settings_menu->display();
    context->selection_menu->display();
    // End ImGui frame
    rlImGuiEnd();
    EndDrawing();
  }
  config_file.open(config_file_name, std::ios::out | std::ios::trunc);
  config_file << context->config_json.dump(2);
  config_file.close();
  rlImGuiShutdown();
  CloseWindow();
  return 0;
}