extern "C" {
#include "modturtle.h"
#include <py/gc.h>
}
#include "turtle.h"

static Turtle sTurtle;

void modturtle_gc_collect() {
  // Mark the shared sTurtle object as a GC root
  for (size_t i = 0; i < sizeof(void *); i++) {
    // See comment in port.cpp: gc_collect implementation
    char * turtleWithOffset = (char *)&sTurtle + i;
    size_t turtleLengthInAddressSize = (sizeof(Turtle) - i + sizeof(void *) - 1)/sizeof(void *);
    gc_collect_root((void **)turtleWithOffset, turtleLengthInAddressSize);
  }
}

void modturtle_view_did_disappear() {
  sTurtle.viewDidDisappear();
}

mp_obj_t modturtle___init__() {
  sTurtle = Turtle();
  /* Note: we don't even bother writing a destructor for Turtle because this
   * init function is called once, and only once, per MicroPython init cycle.
   * When the previous Turtle object is destroyed, its VM is long gone. */
  return mp_const_none;
}

mp_obj_t modturtle_reset() {
  sTurtle.reset();
  // Cf comment on modkandinsky_draw_string
  micropython_port_interrupt_if_needed();
  return mp_const_none;
}

mp_obj_t modturtle_forward(mp_obj_t px) {
  sTurtle.forward(mp_obj_get_float(px));
  return mp_const_none;
}

mp_obj_t modturtle_backward(mp_obj_t px) {
  sTurtle.backward(mp_obj_get_float(px));
  return mp_const_none;
}

mp_obj_t modturtle_right(mp_obj_t angle) {
  sTurtle.right(mp_obj_get_float(angle));
  return mp_const_none;
}

mp_obj_t modturtle_left(mp_obj_t angle) {
  sTurtle.left(mp_obj_get_float(angle));
  return mp_const_none;
}

mp_obj_t modturtle_circle(size_t n_args, const mp_obj_t *args) {
  mp_int_t radius = mp_obj_get_int(args[0]);

  if (n_args == 1) {
    sTurtle.circle(radius);
  }
  else {
    mp_float_t angle = mp_obj_get_float(args[1]);
    sTurtle.circle(radius, angle);
  }
  return mp_const_none;
}

mp_obj_t modturtle_goto(size_t n_args, const mp_obj_t *args) {
  mp_float_t x = 0;
  mp_float_t y = 0;

  if (n_args == 1) {
    mp_obj_t * mp_coords;
    mp_obj_get_array_fixed_n(args[0], 2, &mp_coords);
    x = mp_obj_get_float(mp_coords[0]);
    y = mp_obj_get_float(mp_coords[1]);
  }
  else {
    x = mp_obj_get_float(args[0]);
    y = mp_obj_get_float(args[1]);
  }

  sTurtle.goTo(x, y);

  return mp_const_none;
}

mp_obj_t modturtle_setheading(mp_obj_t angle) {
  sTurtle.setHeading(mp_obj_get_float(angle));
  return mp_const_none;
}

mp_obj_t modturtle_speed(size_t n_args, const mp_obj_t *args) {
  if (n_args == 0) {
    return MP_OBJ_NEW_SMALL_INT(sTurtle.speed());
  }
  sTurtle.setSpeed(mp_obj_get_int(args[0]));
  return mp_const_none;
}

mp_obj_t modturtle_position() {
  mp_obj_t mp_pos[2];
  mp_pos[0] = mp_obj_new_float(sTurtle.x());
  mp_pos[1] = mp_obj_new_float(sTurtle.y());
  return mp_obj_new_tuple(2, mp_pos);
}

mp_obj_t modturtle_heading() {
  return mp_obj_new_float(sTurtle.heading());
}

mp_obj_t modturtle_pendown() {
  sTurtle.setPenDown(true);
  return mp_const_none;
}

mp_obj_t modturtle_penup() {
  sTurtle.setPenDown(false);
  return mp_const_none;
}

mp_obj_t modturtle_pensize(size_t n_args, const mp_obj_t *args) {
  if (n_args == 0) {
    return MP_OBJ_NEW_SMALL_INT(sTurtle.penSize());
  }
  sTurtle.setPenSize(mp_obj_get_int(args[0]));
  return mp_const_none;
}

mp_obj_t modturtle_isdown() {
  return sTurtle.isPenDown() ? mp_const_true : mp_const_false;
}

mp_obj_t modturtle_pencolor(size_t n_args, const mp_obj_t *args) {
  if (n_args == 0) {
    // pencolor()
    KDColor c = sTurtle.color();
    mp_obj_t mp_col[3];
    mp_col[0] = mp_obj_new_int_from_uint(c.red());
    mp_col[1] = mp_obj_new_int_from_uint(c.green());
    mp_col[2] = mp_obj_new_int_from_uint(c.blue());
    return mp_obj_new_tuple(3, mp_col);
  }
  if (n_args == 1) {
    if (MP_OBJ_IS_STR(args[0])) {
      // pencolor("blue")
      size_t l;
      sTurtle.setColor(mp_obj_str_get_data(args[0], &l));
    } else {
      // pencolor((r, g, b))
      mp_obj_t * rgb;
      mp_obj_get_array_fixed_n(args[0], 3, &rgb);
      sTurtle.setColor(
          KDColor::RGB888(
            mp_obj_get_int(rgb[0]),
            mp_obj_get_int(rgb[1]),
            mp_obj_get_int(rgb[2])));
    }
  } else if (n_args == 3) {
    // pencolor(r, g, b)
    sTurtle.setColor(
        KDColor::RGB888(
          mp_obj_get_int(args[0]),
          mp_obj_get_int(args[1]),
          mp_obj_get_int(args[2])));
  }
  return mp_const_none;
}

mp_obj_t modturtle_showturtle() {
  sTurtle.setVisible(true);
  return mp_const_none;
}

mp_obj_t modturtle_hideturtle() {
  sTurtle.setVisible(false);
  return mp_const_none;
}

mp_obj_t modturtle_isvisible() {
  return sTurtle.isVisible() ? mp_const_true : mp_const_false;
}