#pragma once
#include "rtt.h"
#include "texture.h"
#include "shader.h"
#include "shape.h"
#include "brush.h"
#include "action.h"

NS_START

class Canvas
{
    Plane m_plane;
    BrushMesh m_mesh;
    bool m_dirty = false;
public:
    bool m_erase = false;
    glm::mat4 m_mvp;
    glm::vec4 m_box;
    int m_width;
    int m_height;
    bool m_use_instanced = false;
    int m_current_layer_idx = 0;
    std::unique_ptr<Stroke> m_current_stroke;
    bool m_show_tmp = false;
    std::vector<Layer> m_layers;
    std::vector<int> m_order;
    RTT m_tmp;
    Texture2D m_tex;
    Texture2D m_tex2;
    Sampler m_sampler;
    Sampler m_sampler_bg;

    bool create(int width, int height);
    void resize(int width, int height);
    void layer_add(std::string name);
    void layer_order(int idx, int pos);
    void stroke_start(glm::vec2 point, float pressure, const ui::Brush& brush);
    void stroke_update(glm::vec2 point, float pressure);
    void stroke_draw();
    void stroke_end();
    void stroke_commit();
    void clear(const glm::vec4& color = { 1, 1, 1, 1 });
};


class ActionStroke : public Action
{
public:
    std::unique_ptr<Stroke> m_stroke;
    std::unique_ptr<uint8_t[]> m_image;
    glm::ivec4 m_box;
    int m_layer_idx;
    Canvas* m_canvas;
    virtual void run() override
    {
        
    }
    virtual void undo() override
    {
        m_canvas->m_layers[m_stroke->m_layer].m_rtt.bindTexture();

        glm::vec2 box_sz = m_box.zw() - m_box.xy();
        glTexSubImage2D(GL_TEXTURE_2D, 0, m_box.x, m_box.y, box_sz.x, box_sz.y, GL_RGBA, GL_UNSIGNED_BYTE, m_image.get());

        m_canvas->m_layers[m_stroke->m_layer].m_rtt.unbindTexture();
    }
};

NS_END