import moderngl_window as mglw
import numpy as np
from pathlib import Path


class GameWindow(mglw.WindowConfig):
    gl_version = 4,3
    window_size = 800,600
    resource_dir = (Path(__file__).parent / 'resources').resolve()
    buttons_held=[0,0,0]
    
    def __init__(self, **kwargs):
        super().__init__(**kwargs)
        
        self.program = self.load_program('render_to_screen.glsl')
        self.texture = self.ctx.texture(self.window_size, 4)
        
        buff = self.ctx.buffer(np.array([
            -1.0, -1.0, 0.0,
             1.0, -1.0, 0.0,
            -1.0,  1.0, 0.0,
            
             1.0, -1.0, 0.0,
             1.0,  1.0, 0.0,
            -1.0,  1.0, 0.0,
        ]).astype("f4").tobytes())
        self.vao = self.ctx.vertex_array(self.program, buff, "in_position")
        
        self.circle_brush_program = self.ctx.compute_shader(self.load_text('circle_brush.glsl'))
    
    def on_mouse_drag_event(self, x, y, dx, dy):
        #print("Mouse drag:", x, y, dx, dy)
        if self.buttons_held[1]:
            self.apply_brush(x,y, dx,dy)
    
    def on_mouse_press_event(self, x, y, button):
        self.buttons_held[button]=True
        if button == 1:
            self.apply_brush(x,y, 0,0)
    
    def on_mouse_release_event(self, x,y, button):
        self.buttons_held[button]=False
    
    def apply_brush(self, x,y, dx, dy):
        self.circle_brush_program["texture0"]=0
        self.circle_brush_program["start"].value = (x,y)
        self.circle_brush_program["stop"].value = (x+dx,y+dy)
        self.texture.use(0)
        self.circle_brush_program.run(*self.window_size)
    
    def on_render(self, time, frametime):
        self.program["texture0"]=0
        self.texture.bind_to_image(0, read=False, write=True)
        self.vao.render()


if __name__ == "__main__":
    GameWindow.run()