using System;
using System.Collections.Generic;
using System.Numerics;
using static OpenGL.GL;
using OpenGLTutorial.Rendering.Cameras;
using OpenGLTutorial.Rendering.Display;
using OpenGLTutorial.Rendering.Objects.Components;
using OpenGLTutorial.Rendering.Shaders;

namespace OpenGLTutorial.Rendering.Objects {
    public class GameObject {
        
        public Shader Shader { get; set; }
        public Shape Shape { get; set; }
        public Texture Texture { get; set; }
        
        public Vector2 Position { get; set; }
        public Vector2 Scale { get; set; }
        public float Rotation { get; set; }

        private List<IComponent> _components;

        public GameObject(Shader shader, Shape shape, Texture texture) {
            Position = Vector2.Zero;
            Scale = Vector2.One;
            Rotation = 0;

            Shader = shader;
            Shape = shape;
            Texture = texture;

            _components = new List<IComponent>();
        }

        public void Load() {
            Shader?.Load();
            Shape?.Load();
            Texture?.Load();
            
            _components.ForEach(component => component.Load(this));
        }

        public void Update() {
            _components.ForEach(component => component.Update(this));
        }

        public void Render(Camera2D cam, int renderMode = GL_TRIANGLES) {
            Matrix4x4 trans = Matrix4x4.CreateTranslation(Position.X, -Position.Y, 0);
            Matrix4x4 sca = Matrix4x4.CreateScale(Scale.X, Scale.Y, 1);
            Matrix4x4 rot = Matrix4x4.CreateRotationZ(Rotation);
            
            Texture?.Use();
            Shader?.Use();
            Shader?.SetMatrix4X4("model", sca * rot * trans);
            Shader?.SetMatrix4X4("projection", cam.GetProjectionMatrix());

            if (Shape?.Vao != null) {
                glBindVertexArray(Shape.Vao);
                glDrawArrays(renderMode, 0, Shape.GetVertexCount());
                glBindVertexArray(0);
            }
            
            _components.ForEach(component => component.Render(this));
        }

        public void Destroy() {
            _components.ForEach(component => component.Destroy(this));
            Shader?.Delete();
            Shape?.Delete();
            Texture?.Delete();
        }
        
        public void AddComponent(IComponent component) => _components.Add(component);
        public T GetComponent<T>() {
            foreach (var component in _components) {
                if (component.GetType() == typeof(T)) return (T)component;
            }

            throw new NullReferenceException("Object does not contain a component of type " + typeof(T));
        }
        public void RemoveComponent<T>() {
            foreach (var component in _components) {
                if (component.GetType() == typeof(T)) {
                    _components.Remove(component);
                    return;
                }
            }

            throw new NullReferenceException("Object does not contain a component of type " + typeof(T));
        }
        
    }
}