#include <cstdio>
#include <SDL3/SDL.h>
#include <GL/glew.h>

#include "gfx/txt_renderer.h"
#include "terminal.h"

Terminal::Terminal(void) {
  /* Placeholder welcome message to history. */
  _history.push_back("Welcome to Bettola");
}

void Terminal::_on_ret_press(void) {
  /* Add the command to history. */
  _history.push_back("> " + _input_buffer);

  /* For now, print the commmand clear buffer.
   * TODO: Parse and execute commands.
   */
  printf("Command entered: %s\n", _input_buffer.c_str());

  if(_input_buffer == "clear") {
    _history.clear();
  } else if(_input_buffer == "help") {
    _history.push_back("Commands: help, clear");
  }

  _input_buffer.clear();
}

void Terminal::handle_input(SDL_Event* event) {
  if(event->type == SDL_EVENT_TEXT_INPUT) {
    /* Append chars to the input buffer. */
    _input_buffer += event->text.text;
  } else if(event->type == SDL_EVENT_KEY_DOWN) {
    /* Handle special keys. */
    if(event->key.key == SDLK_BACKSPACE && _input_buffer.length() > 0) {
      _input_buffer.pop_back();
    } else if(event->key.key == SDLK_RETURN) {
      _on_ret_press();
    }
  }
}

void Terminal::render(TextRenderer* renderer, int x, int y, int width, int height) {
  float white[]     = { 1.0f, 1.0f, 1.0f };
  float green[]     = { 0.2f, 1.0f, 0.2f };
  float line_height = 20.0f;
  float padding     = 5.0f;

  /* Enable scissor test to clip rendering to the window content area. */
  glEnable(GL_SCISSOR_TEST);
  glScissor(x, y, width, height);

  /* Draw history. */
  for(size_t i = 0; i < _history.size(); ++i) {
    float y_pos = (y+height) - padding - line_height - (i*line_height);
    renderer->render_text(_history[i].c_str(), x+padding, y_pos, 1.0f, white);
  }

  /* Draw current input line. */
  std::string prompt = "> " + _input_buffer;
  float prompt_y_pos = (y+height) - padding - line_height - (_history.size()*line_height);
  renderer->render_text(prompt.c_str(), x+padding, prompt_y_pos, 1.0f, green);

  /* Disable scissor test. */
  glDisable(GL_SCISSOR_TEST);
}