local modname = minetest.get_current_modname()
local modpath = minetest.get_modpath(modname)

local END_EXIT_PORTAL_POS_X = -3
local END_EXIT_PORTAL_POS_Y = -27003
local END_EXIT_PORTAL_POS_Z = -3
local p0 = {
	x = END_EXIT_PORTAL_POS_X,
	y = END_EXIT_PORTAL_POS_Y,
	z = END_EXIT_PORTAL_POS_Z,
}

local schematic = modpath .. "/schematics/mcl_structures_end_exit_portal.mts"

local function place(pos, rotation, pr)
	mcl_structures.place_schematic({pos = pos, schematic = schematic, rotation = rotation, pr = pr})
end

mcl_mapgen.register_mapgen(function(minp, maxp, seed, vm_context)
	local minp = minp
	local y1 = minp.y
	if y1 > END_EXIT_PORTAL_POS_Y then return end
	local maxp = maxp
	local y2 = maxp.y
	if y2 < END_EXIT_PORTAL_POS_Y then return end
	if minp.x > END_EXIT_PORTAL_POS_X then return end
	if maxp.x < END_EXIT_PORTAL_POS_X then return end
	if minp.z > END_EXIT_PORTAL_POS_Z then return end
	if maxp.z < END_EXIT_PORTAL_POS_Z then return end

	local p = table.copy(p0)

	for y = y2, y1, -1 do
		p.y = y
		if minetest.get_node(p).name == "mcl_end:end_stone" then
			place(p, "0", PseudoRandom(vm_context.chunkseed))
			return
		end
	end

	for y = y2, y1, -1 do
		p.y = y
		if minetest.get_node(p).name ~= "air" then
			place(p, "0", PseudoRandom(vm_context.chunkseed))
			return
		end
	end

	place(p0, "0", PseudoRandom(vm_context.chunkseed))
end)

mcl_structures.register_structure({name = "end_exit_portal", place_function = place})