extends Node

func settle() -> void:
	for frame in 4: await get_tree().process_frame
	await RenderingServer.frame_post_draw

func difference(a: Image, b: Image, center: Vector2) -> float:
	var total := 0.0
	var samples := 0
	for y in range(int(center.y)-55,int(center.y)+55,2):
		for x in range(int(center.x)-55,int(center.x)+55,2):
			if x < 0 or y < 0 or x >= a.get_width() or y >= a.get_height(): continue
			var first := a.get_pixel(x,y)
			var next := b.get_pixel(x,y)
			total += absf(first.r-next.r)+absf(first.g-next.g)+absf(first.b-next.b)
			samples += 3
	return total/maxi(1,samples)

func _ready() -> void:
	var sheet := Image.create(1280,1080,false,Image.FORMAT_RGBA8)
	var max_pan_change := 0.0
	var progress: Resource = GameState.captain.expedition
	for biome in 6:
		var profile: Dictionary = preload("res://scripts/planets/planet_profiles.gd").generate(99,biome,"Złoże / biom %d" % (biome+1))
		profile.temperature = 75 if biome == 4 else (-35 if biome == 5 else 20)
		progress.lander_hp = 100
		assert(progress.begin_visit(profile))
		progress.visit_seed = 200+biome
		var surface := Control.new()
		surface.set_script(preload("res://scripts/planets/surface_screen.gd"))
		surface.captain = GameState.captain
		surface.progress = progress
		add_child(surface)
		surface.set_process(false)
		surface.set_physics_process(false)
		surface.lander.hide()
		surface._surface_viewport.get_node("SurfaceAtmosphere").hide()
		var target := Vector2.INF
		var chosen: Sprite2D
		for poi in surface.world.data.pois:
			if poi.kind != "deposit": continue
			var sprite: Sprite2D = surface.world._poi_sprites[poi.id]
			assert(sprite.texture.resource_path == "res://assets/planets/mineral_deposit.png")
			assert(sprite.texture_filter == CanvasItem.TEXTURE_FILTER_LINEAR_WITH_MIPMAPS)
			assert(sprite.texture.get_image().has_mipmaps())
			assert(sprite.material.shader.resource_path.ends_with("mineral_deposit.gdshader"))
			assert(not sprite.material.shader.code.contains("TIME"))
			if poi.position.length_squared() < target.length_squared():
				target = poi.position
				chosen = sprite
		assert(chosen != null)
		surface.world.refresh_pois(target)
		surface.camera.position_smoothing_enabled = false
		surface.camera.position = target
		surface.camera.force_update_scroll()
		await settle()
		var origin: Vector2 = chosen.get_global_transform_with_canvas().origin/surface.SURFACE_RENDER_SCALE
		var initial: Image = get_viewport().get_texture().get_image()
		initial.save_png("res://artifacts/mineral_deposit_biome_%d.png" % biome)
		var small := initial.duplicate() as Image
		small.convert(Image.FORMAT_RGBA8)
		small.resize(640,360,Image.INTERPOLATE_LANCZOS)
		sheet.blit_rect(small,Rect2i(0,0,640,360),Vector2i(biome%2*640,biome/2*360))
		if biome == 0:
			await settle()
			assert(difference(initial,get_viewport().get_texture().get_image(),origin) < 0.0001,"Stationary ore must not flicker")
			var previous := initial
			for frame in 12:
				surface.camera.position = target+Vector2((frame+1)*0.25,0)
				surface.camera.force_update_scroll()
				await settle()
				var current: Image = get_viewport().get_texture().get_image()
				var change := difference(previous,current,origin)
				max_pan_change = maxf(max_pan_change,change)
				assert(change < 0.035,"Subpixel camera motion should remain smoothly filtered")
				previous = current
			surface.camera.position = target
			surface.camera.force_update_scroll()
			await settle()
			assert(difference(initial,get_viewport().get_texture().get_image(),origin) < 0.0001,"Returning to the same camera position restores the same pixels")
		progress.finish_visit(GameState.captain,false)
		surface.queue_free()
		await get_tree().process_frame
	sheet.save_png("res://artifacts/mineral_deposit_biomes.png")
	print("MINERAL DEPOSIT PASS: six biome renders, real ore instead of icon, mipmaps, alpha/soil blending, no stationary flicker, smooth subpixel panning, identical pixels after camera return; max mean pan delta=",max_pan_change)
	get_tree().quit()