shader_type canvas_item;
 
uniform vec4 dawn_color : hint_color = vec4(0.86, 0.70, 0.70, 1.0);
uniform vec4 day_color : hint_color = vec4(1.0, 1.0, 1.0, 1.0);
uniform vec4 dusk_color : hint_color = vec4(0.59, 0.66, 0.78, 1.0);
uniform vec4 night_color : hint_color = vec4(0.07, 0.09, 0.38, 1.0);

uniform float brightness : hint_range(0.0, 10.0, 0.01) = 1.0;
uniform float contrast : hint_range(0.0, 10.0, 0.01) = 1.0;
uniform float saturation : hint_range(0.0, 10.0, 0.01) = 1.0;
uniform float pop_strength : hint_range(0.0, 10.0, 0.01) = 1.0;
uniform float pop_threslhold : hint_range(0.0, 10.0, 0.01) = 1.0;

uniform bool overlay = false;

void fragment() {
	vec3 cycle_color = night_color.rgb;
	
	vec3 base_col = texture(SCREEN_TEXTURE, SCREEN_UV).rgb;
	vec3 out_col = base_col;
	vec4 final_color;

	float grey = dot(base_col, vec3(0.299, 0.587, 0.114));

	if (overlay) {
		if (grey > 0.5) {
			out_col = 1.0 - (1.0 - 2.0 * (base_col - 0.5)) * (1.0 * cycle_color.rgb);
		} else {
			out_col = 2.0 * base_col * cycle_color.rgb;
		}
	}
	
	out_col = mix(vec3(grey), out_col, saturation);
	out_col = (out_col - 0.5) * contrast + 0.5;
	out_col = out_col + pop_strength * max(grey - pop_threslhold, 0.0);
	out_col = out_col * brightness;

	if (AT_LIGHT_PASS) {
		vec3 lights_col= texture(TEXTURE, UV).rgb;
		grey = dot(lights_col, vec3(0.333));
		out_col = mix(out_col, base_col * normalize(lights_col + 0.05) * 3.0, grey);
		out_col += 0.1 * lights_col; // optional 
		
		final_color = vec4(out_col, 1.0);
	} else {
		final_color = vec4(out_col * cycle_color.rgb, 1.0);
	}
	
	COLOR = final_color;
}