# Copyright 2022 Frederico de Oliveira Linhares
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

CAMERA_ROTATION_SPEED = Math::PI/45;
BOX_ROTATION_SPEED = Math::PI/180;
TRANSLATION_SPEED = 0.5;

def init()
  $texture = CandyGear::Texture.from_image("textures/color_texture.png");
  $model = CandyGear::Model.new("models/cube.cgmodel", $texture);
  $sprite = CandyGear::Sprite.new(
    $texture, CandyGear::Vector4D.new(0, 0, 1.0, 1.0));
  $sprite_position = CandyGear::Vector4D.new(1.0, 1.0, 101.0, 101.0);

  $instances = [
    CandyGear::Vector3D.new(5.0, 0.0, 0.0),
    CandyGear::Vector3D.new(-5.0, 0.0, 0.0),
    CandyGear::Vector3D.new(0.0, 5.0, 0.0),
    CandyGear::Vector3D.new(0.0, -5.0, 0.0),
    CandyGear::Vector3D.new(0.0, 0.0, 5.0),
    CandyGear::Vector3D.new(0.0, 0.0, -5.0)
  ];
  $instances_rotation = CandyGear::Rotation3D.new(0.0, 0.0, 0.0);

  $camera_position = CandyGear::Vector3D.new(0.0, 0.0, 0.0);
  $camera_rotation = CandyGear::Rotation3D.new(0.0, 0.0, 0.0);

  color = CandyGear::Vector3D.new(0.12, 0.12, 0.18);
  $view1 = CandyGear::View.new(CandyGear::Vector4D.new(0, 0, 1280, 360));
  $view2 = CandyGear::View.new(CandyGear::Vector4D.new(0, 360, 1280, 360));
  CandyGear.views = [$view1, $view2];

  $view1.camera_position = $camera_position;
  $view1.camera_rotation = $camera_rotation;
end

def key_down(key)
  case key
  when CandyGear::Key::I
    $camera_rotation.rotate(CAMERA_ROTATION_SPEED, 0.0);
  when CandyGear::Key::K
    $camera_rotation.rotate(-CAMERA_ROTATION_SPEED, 0.0);
  when CandyGear::Key::J
    $camera_rotation.rotate(0.0, CAMERA_ROTATION_SPEED);
  when CandyGear::Key::L
    $camera_rotation.rotate(0.0, -CAMERA_ROTATION_SPEED);
  when CandyGear::Key::E
    $camera_position.translate(
      CandyGear::Vector3D.new(0.0, 0.0, -TRANSLATION_SPEED), $camera_rotation);
  when CandyGear::Key::D
    $camera_position.translate(
      CandyGear::Vector3D.new(0.0, 0.0, TRANSLATION_SPEED), $camera_rotation);
  when CandyGear::Key::S
    $camera_position.translate(
      CandyGear::Vector3D.new(-TRANSLATION_SPEED, 0.0, 0.0), $camera_rotation);
  when CandyGear::Key::F
    $camera_position.translate(
      CandyGear::Vector3D.new(TRANSLATION_SPEED, 0.0, 0.0), $camera_rotation);
  end
end

def key_up(key)
end

def quit() = CandyGear.quit();

def tick()
  $sprite.draw($view2, $sprite_position);
  $instances_rotation.rotate(0.0, BOX_ROTATION_SPEED);
  $instances.each do |i|
    $model.draw(i, $instances_rotation);
  end
end